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HomeMy WebLinkAboutPermit L96-0041 - BOEING #9-150 - DUWAMISH WEST RIVERBANK SHORELINE SUBSTANTIAL DEVELOPMENTL96 -0041 DUWAMISH W. RIVERBANK VICINITY OF S 102 ST SHORELINE REPLY TO ATTENTION OF Regulatory Branch DEPARTMENT OF THE ARMY SEATTLE DISTRICT. CORPS OF ENGINEERS P.O. BOX 3755 SEATTLE, WASHINGTON 98124-2255 NOV 7 O 1996 RECEIVED NOV 1 51996 TUKWILA PUBLIC WORM Boeing Defense and Space Group ATTN: Mr. Terry Bennett Post Office Box 3707 M/A 46 -87 Seattle, Washington 98124 -2207 Reference: 96 -4 -01110 Boeing Company Dear Mr. Bennett: The notification procedure has been completed. Nationwide Permit 13 authorizes your bank protection project located in sec. 4, T. 23 N., R. 4E., at Seattle, King County, Washington. You must meet the specific requirements and the conditions. The regulations which govern our permit program contain a series of nationwide permits. Each nationwide permit authorizes a specific category of work, provided certain conditions are met. Nationwide Permit 13 (33 CFR 330 Appendix A, Paragraph B (13)) allows bank stabilization activities: Bank stabilization activities necessary for erosion prevention . . . . The entire text of Nationwide Permit 13, Nationwide Permit Conditions, and drawings are enclosed. This verification will be valid for a period of 2 years from the date of this letter or until the nationwide permit is modified, reissued, or revoked. This nationwide permit is scheduled to expire January 21, 1997, but is expected to be reissued. The verification will remain valid for 2 years if reissuance of this nationwide permit is not modified or your proposed work complies with any subsequent modification. While you need no further authorization from us, you must still comply with other Federal, State, and local requirements z z1 ~ w. 00 o W =' w o: co • LU w Z f-. U so tr-, • w o . Z` 1=1.; -2- which may pertain to the work. If you have any questions, please contact Mr. Jonathan Freedman at the above address or by telephone at (206) 764 -3495. Enclosures Robert H. Martin Chief, Processing Section .+..., a�4: v::'('. W�:: b?. r•'' r ..'..i.'.i;r:�::'wSi::!1wfhL ='i 1;c;; +:'�:3ti�Ea:i'.��:e6. nSi. YYr :Hw'� %Pall i-i "fi`. JR'S..`l:V.141 •z ev:.fw.euat &23 R te. 0t: • 13. BANK STABILIZATION. Bank stabilization activities necessary for erosion prevention provided: a. No material is placed in excess of the minimum needed for erosion protection; b. The bank stabilization activity is less than 500 feet in length; c. The activity will not exceed an average of one cubic yard per running foot placed along the bank below the plane of the ordinary high water mark or the high tide line; d. No material is placed in any special aquatic site, including wetlands; e. No material is of the type or is placed in any location or in any manner so as to impair surface water flow into or out of any wetland area; f. No material is placed in a manner that will be eroded by normal or expected high flows (properly anchored trees and treetops may be used in low energy areas); and, g. The activity is part of a single and complete project. Bank stabilization activities in excess of 500 feet in length or greater than an average of one cubic yard per running foot may be authorized if the permittee notifies the District Engineer in accordance with the "Notification" general condition and the District Engineer determines the activity complies with the other terms and conditions of the nationwide permit and the adverse environmental impacts are minimal both individually and cumulatively. (Sections 10 and 404) Regional Conditions - 1. Bank stabilization activities exceeding 1/2 cubic yard of fill material per running foot may be authorized if the permittee notifies the District Engineer in accordance with the "Notification" general condition and the adverse impacts are determined to be minimal. 2. When revegetation is necessary, native vegetation shall be utilized to the fullest extent possible given a reasonable likelihood of success. Measures such as hydroseeding may be used for temporary erosion control. 401 Certification - NWP partially denied without prejudice. An individual certification or demonstration of State waiver of such certification to the District Engineer is required for the following: a) Bank stabilization projects that exceed an average of 1/2 cubic yard of solid pour concrete per running foot placed along the bank below the plane of ordinary high water or mean higher high water in tidal areas. b) Bank stabilization that exceeds 500 feet in length and does not incorporate structures and /or modifications that are RECEIVED NOV 151996 TUKWILA PUBLIC WORK$ beneficial as fish or wildlife habitat, are not designed and constructed in accordance to current engineering standards, and do not meet the requirements of the State Department of Fisheries or Wildlife. CZM Consistency Determination - NWP partially denied without prejudice subject to 401 Certification conditions. An individual CZM Consistency Determination is required from the State for projects that exceed the noted limits and are located in counties within the coastal zone. J:U • .0 O; CO C:1:, W'=; J W O: J =.O • • _.. z IO (121C z V: IL II' z, O 17 Z NATIONWIDE PERMIT CONDITIONS General Regional Condition for the State of Washinaton applicable to all nationwide permits (NWP): Any activity or work authorized under these NWP shall not adversely impact onsite mitigation or restoration efforts. 33 CFR Part 330, Aopendix A, Section C. GENERAL CONDITIONS: The following general conditions must be followed in order for any authorization by a NWP to be valid: 1. Navigation. No activity may cause more than a minimal adverse effect on navigation. 2. Proper maintenance. Any structure or fill authorized shall he properly maintained, including maintenance to ensure public safety. 3. Erosion and siltation controls. Appropriate erosion and siltation controls must be used and maintained in effective operating condition during construction, and all exposed soil and other fills must be permanently stabilized at the earliest practicable date. 4. Aquatic life movements. No activity may substantially disrupt the movement of those species of aquatic life indigenous to the waterbody, including those species which normally migrate through the area, unless the activity's primary purpose is to impound water. 5. Equipment. Heavy equipment working in wetlands must be placed on mats or other measures must be taken to minimize soil disturbance. 6. Regional and case -by -case conditions. The activity must comply with any regional conditions which may have been added by the Division Engineer (see 33 CFR 330.4(e)) and any case specific conditions added by the Corps of Engineers (Corps). 7. Wild and scenic rivers. No activity may occur in a component of the National Wild and Scenic River System; or in a river officially designated by Congress as a "study river" for possible inclusion in the system, while the river is in an official study status. Information on Wild and Scenic Rivers may be obtained from the National Park Service and the U.S. Forest Service. 8. Tribal rights. No activity or its operation may impair reserved tribal rights, including, but not limited to, reserved water rights and treaty fishing and hunting rights. 9. Water quality certification. In certain States, an individual State water quality certification must be obtained or waived (see 33 CFR 330.4(c)). RECEIVED NOV 15 1996 TUKWILA PUBLIC WORK-6 z z�. ►— w CC UO co J=, F- w0 U.¢ U =d , _ z �. �- o z F- LU uj Ui =: C] ww iu = P 1- z 10. Coastal zone management. In certain States, an individual State coastal zone management consistency concurrence must be obtained or waived (see 33 CFR 330.4(d)). 11. Endangered species. No activity is authorized under any NWP which is likely to jeopardize the continued existence of a threatened or endangered species or a species proposed for such designation, as identified under the Federal Endangered Species Act, or which is likely to destroy or adversely modify the critical habitat of such species. Nonfederal permittees shall notify the District Engineer if any listed species or critical habitat might be affected or is in the vicinity of the project and shall not begin work on the activity until notified by the District Engineer that the requirements of the Endangered Species Act have been satisfied and that the activity is authorized. Information on the location of threatened and endangered species and their critical habitat can be obtained from the U.S. Fish and Wildlife Service and National Marine Fisheries Service (USFWS /NMFS) (see 33 CFR 330.4(f)). 12. Historic properties. No activity which may affect historic properties listed, or eligible for listing, in the National Register of Historic Places is authorized, until the District Engineer has complied with the provisions of 33 CFR 325, Appendix C. The prospective permittee must notify the District Engineer if the authorized activity may affect any historic properties listed, determined to be eligible, or which the prospective permittee has reason to believe may he eligible for listing on the National Register of Historic • Places, and shall not begin the activity until notified by the District Engineer that the requirements of the National Historic Preservation Act have been satisfied and that the activity is authorized. Information on the location and existence of historic resources can he obtained from the State Historic Preservation Office (SHPO) and the National Register of Historic Places (see 33 CFR 330.4(g)). 13. Notification. (a) Where required by the terms of the NWP, the prospective permittee must notify the District Engineer as early as possible and shall not begin the activity: (1) Until notified by the District Engineer that the activity may proceed under. the NWP with any special conditions imposed by the District or Division Engineer; or (2) If notified by the District or Division Engineer that an individual permit is required; or (3) Unless 30 days have passed from the District Engineer's receipt of the notification and the prospective permittee has not received notice from the District or Division Engineer. Subsequently, the permittee's right to proceed under the NWP may be modified, suspended, or revoked only in accordance with the procedure set forth in 33 CFR 330.5(d)(2). 2 :ii:�YPf tYaw '"?'v3bYr' .Fiiw :i414 3a .RinAf Art• -,rx . ',Lg. • z • w 6 D. O 0 • . �o J = NLL w O' g Q: =a w 1- 0 • • wI uj UC) .:o -. 'o w w: 1- z • w U :0 z (b) The notification must be in writing and include the following information and any required fees: (1) Name, address, and telephone number of the prospective permittee; (2) Location of the proposed project; z (3) Brief description of the proposed project; the project's purpose; il- l- direct and indirect adverse environmental effects the project would cause; any W other NWP(s), regional general permit(s), or individual permit(s) used or 6 intended to be used to authorize any part of the proposed project or any -J o, related activity; w 0, (0 Ill (4) Where required by the terms of the NWP, a delineation of affected -1 1 special aquatic sites, including wetlands; and uj u- w0 (5) A statement that the prospective permittee has contacted: u_1-1 (i) The USFWS /NMFS regarding the presence of any federally listed N OD a (or proposed for listing) endangered or threatened species or critical habitat Ii w. in the permit area that may be affected by the proposed project; and any z available. information provided by those agencies. (The prospective permittee Z 0 '-'. may contact Corps District Offices for USFWS /NMFS agency contacts and lists of w w critical habitat.) D Do (ii) The SHPO regardina the presence of any historic properties in o �. the permit area that may be affected by the proposed project; and the wiu available information, if any, provided by that agency. 1- 7. (c) The standard individual permit application form (Form ENG 4345) may by iiiz used as the notification but must clearly indicate that it is a predischarge o co notification (PDN) and must include all of the information required in o 1_. (b)(1) -(5) of General Condition 13. z (d) In reviewing an activity under the notification procedure, the District Engineer will first determine whether the activity will result in more than minimal individual or cumulative adverse environmental effects or will be contrary to the public interest. The prospective permittee may, at his option, submit a proposed mitigation plan with the predischarge notification to expedite the process and the District Engineer will consider any optional mitigation the applicant has included in the proposal in determining whether, the net adverse environmental effects of the proposed work are minimal. The District Engineer will consider any comments from Federal and State agencies concerning the proposed activity's compliance with the terms and conditions of the NWP and the need for mitigation to reduce the project's adverse environ- mental effects to a minimal level. The District Engineer will upon receipt of a notification provide immediately (e.g., facsimile transmission, overnight mail, or other expeditious manner) a copy to the appropriate offices of the USFWS, State natural resource or water quality agency, EPA, and, if appropri- ate, the NMFS. With the exception of NWP 37, these agencies will then have 5 calendar days from the date the material is transmitted to telephone the 3 r District Engineer if they intend to provide substantive, site - specific comments. If so contacted by an agency, the District Engineer will wait an additional 10 calendar days before making a decision on the notification. The District Engineer will fully consider agency comments received within the specified timeframe, but will provide no response to the resource agency. The District Engineer will indicate in the administrative record associated with each notification that the resource agencies' concerns were considered. Applicants are encouraged to provide the Corps multiple copies of notifica- tions to expedite agency notification. If the District Engineer determines that the activity complies with the terms and conditions of the NWP and that the adverse effects are minimal, he will notify the permittee and include any conditions he deems necessary. If the District Engineer determines that the adverse effects of the proposed work are more than minimal, then he will notify the applicant either: (1) that the project does not qualify for authorization under the NWP and instruct the applicant on the procedures to seek authorization under an individual permit; or (2) that the project is authorized under the NWP subject to the applicant's submitting a mitigation proposal that would reduce the adverse effects to the minimal level. This mitigation proposal must be approved by the District Engineer prior to commencing work. If the prospective permittee elects to submit a mitigation plan, the District Engineer will expeditiously review the proposed mitigation plan, but will not commence a second 30 -day notification procedure. If the net adverse effects of the project (with the mitigation proposal) are deter- mined by the District Engineer to be minimal, the District Engineer will provide a timely written response to the applicant informing him that the project can proceed under the terms and conditions of the NWP. (e) Wetlands delineations: Wetland delineations must be prepared in accordance with the current method required by the Corps. The permittee may ask the Corps to delineate the special aquatic site. There may be some delay . if the Corps does the delineation. Furthermore, the 30 -day period will not start until the wetland delineation has been completed. (f) Mitigation: Factors that the District Engineer will consider when determining the acceptability of appropriate and practicable mitigation include, but are not limited to: (1) To be practicable, the mitigation must he available and capable of being done considering costs, existing technology, and logistics in light of overall project purposes; (2) To the extent appropriate, permittees should consider mitigation banking and other forms of mitigation including contributions to wetland trust funds, which contribute to the restoration, creation, replacement, enhancement, or preservation of wetlands. Furthermore, examples of mitigation that may he appropriate and practicable include but are not limited to: reducing the size of the project; establishing buffer zones to protect aquatic resource values; and replacing the loss of aquatic resource values by creating, restoring, and enhancing similar func- tions and values. In addition, mitigation must address impacts and cannot be 4 used to offset the acreage of wetland losses that would occur in order to meet the acreage limits of some of the NWP's (e.g., 5 acres of wetlands cannot be created to change a 6 -acre loss of wetlands to a 1 -acre loss; however, the 5 created acres can be used to reduce the impacts of the 6 -acre loss). SECTION 404 ONLY CONDITIONS: In addition to the general conditions, the following conditions apply only to activities that involve the discharge of a z t-= dredged or fill material and must be followed in order for authorization by F-- z the NWP's to be valid: ix 1. Water supply intakes. No discharge of dredged or fill material may d o. occur in the proximity of a public water supply intake except where the N °. discharge is for repair of the public water supply intake structures or w = adjacent bank stabilization. co u. w o. 2. Shellfish production. No discharge of dredged or fill material may occur in areas of concentrated shellfish production, unless the discharge is ga 5, directly related to a shellfish harvesting activity authorized by NWP 4. N a. =w 3. Suitable material. No discharge of dredged or fill material may consist of unsuitable material (e.g., trash, debris, car bodies, etc.) and iZ material discharged must be free from toxic pollutants in toxic amounts (see z o Section 307 of the Clean Water Act). LIJ 0; 4. Mitigation. Discharges of dredged or fill material into waters of the 0 N. United States must be minimized or avoided to the maximum extent practicable 0 F- at the project site (i.e., onsite), unless the District Engineer has approved = w; a compensation mitigation plan for the specific regulated activity. _ p, 5. Spawning areas. Discharges in spawning areas during spawning seasons iuiz` must be avoided to the maximum extent practicable. OH 6. Obstruction of high flows. To the maximum extent practicable, discharges must not permanently restrict or impede the passage of normal or expected high flows or cause the relocation of the water (unless the primary purpose of the fill is to impound waters). 7. Adverse impacts from impoundments. If the discharge creates an impoundment of water, adverse impacts on the aquatic system caused by the accelerated passage of water and /or the restriction of its flow shall be minimized to the maximum extent practicable. 8. Waterfowl breeding areas. Discharges into breeding areas for migratory waterfowl must be avoided to the maximum extent practicable. 9. Removal of temporary fills. Any temporary fills must be removed in . their entirety and the affected areas returned to their pre- existing elevation. BM -7; NPDCOND 4105,1 16. itE�3c:Poi% .e t6"f ' k: ` < +.• , 5 is i` j ll v <L L 2.5 MI. 551 IDES MOINES) 1578 IV NE SCALE 1:24000 0 553 4-- _ °301 . -- 22°17'30" 1.8 MI. TO INTERSTATE 5 1 MILE 1000 0 1000 2000 3000 4000 5000 6000 7000 FEET VICINITY NAP SCALE: 1' =24000 r= unr.>m t ... ro "h- .�gx.5•tan.. vie^�`rw.:+>1.tih_..,,e�wl�C�r+ .... .":M1-^.'��: r"'.1x., «. • \ • wicart,M. ■.I TACOMA 25 MI.\ 555 OLYMPIA 50 MI. A, (; tL' e -z- o PROPOSAL:. RIVERBANK STABILIZATION AT. 7 LOCATIONS IN: DUWAMISH RIVER AT: TUKWILA, WA COUNTY OF: KING STATE: WASHINGTON APPL BY: BOEING DEFENSE do SPACE GROUP PAGE: 1 OF 17 DATE: 06.14.96 -ft Z ~ W re r QQ JU UO U0, W W• O aQ I• CI F- Z= I— O Z I- LL! w 0 O— cal- 111 W 2 H � O � ..z w U= 0 z rPAGE TOT- 11 L f S 102ND ST. N88'51'51 "W f • (PAGE 8o7. 171 I � I 1 1 — 7 PK NAIL WITH 23 +02.79 BASELINE \ I PAGE 77 —OF 171 CONTROL FLASHER L KEY P_AN. I 13 +37.71 BASELINE --f \ / PK NAIL WITH I \ I CONTROL FLASHER \ / I 1 /I 9 +07.99 BASELINE \ LtAGE 6 OF 171 _ /_ j HUB & TACK \\ � l • 1 5 +79.63 BASELINE 1 REBAR WITH RED [AfE5oFiZ] CONTROL CAP _— _ _ I GE40F 171 i SCALE: NO SCALE • 2 +00.00 BASELINE PK NAIL WITH CONTROL FLASHER 0 +00 BASELINE HUB & TACK AGE 3 OF 17 A . (, ca.j ;d., - L(_ Q (((0 PROPOSAL: RIVERBANK STABILIZATION AT 7 LOCATIONS IN: DUWAMISH RIVER AT: TUKWILA, WA COUNTY OF: KING STATE: WASHINGTON APPL BY: BOEING DEFENSE & SPACE GROUF PAGE: 2 OF 17 DATE: 06.14.96 Z • IX 2 JU U O` ww ALI I, N �: w Oi lL Q; co _. F_w. , z � • z U • O 13 y2, ww IL :. • Air on O 1— 10 WILLVW 12" GATED 12" STEEL PIPE I.E. = 4.87 2 +62.5 PATH 82.5' C8o C 0 13. 12.8 REMOVE 14" WILLOW 12.6 0 2 +00 BASELIN PK NAIL WITH CONTROL FLASH: 12.4 0, 1 +52 C 13.6 12" WILLOW LIMIT 13.4 GRAD „If) i /MEW 44 080 0 , /����A Wyc' � • •� //r Vii. 3.3 OM // . ■ .11:rxr.orAtity mare 13.1 IA r / /.I 12.7,1 rmuliwAm !'�,. .7�r/Iti:f•r.o wit fi���4�I�I,�j� /lll /I // / //I INK i �1::�,1I /// ��1.f..� 12.7 I I1n u % L4ya�♦� ••I lfl%�/ I ��k •' OR�* ul,,,,,_�ri - 13.5 '1oWtt l♦' .�' � 1 W/114, vrip NOV i %-.•, • �` 13.1 13.1 13.5 12" WILLOW- UMIT OF GRADING `0. Ai AP' C514 14.4 -8.0 5.10 OHW 4.24 MHW 4'°r77// ' 14.3 FOR VEGETATED GEOGRID CONSTRUCTION DETAILS, SEE SHEET LS500 FOR SEEDED AREAS DETAILS SEE SHEET LS500 PAN - AREA 1 SCALE 1" =20' CONTOUR INTERVAL = 1 DATUM: USGS MSL !f�1M1V�l...Nt.• rn 9 • • I 'C -Z - 0II(0 PROPOSAL: RIVERBANK STABILIZATION AT 7 LOCATIONS • IN: DUWAMISH RIVER AT: TUKWILA, WA COUNTY OF: KING STATE: WASHINGTON APPL BY: BOEING DEFENSE & SPACE GROUP PAGE: 3 OF 17 DATE: 06.14.96 z < • w re m. O 0 (0 J Lu 1- w 0. 2 u-a w zF... W O U0 0 I- w LLI z; 0 • 5 +79.63 BASELINE REBAR WITH RED CONTROL CAP 3 +53,25 X 12.9 3 +31.5 oak 414 cao csoo ifiligrO4 Cao C5Q 3.1 !��Alfa , 13.2 C80,A I.� / /. x 13.4 CJuu t' 7 24 " COTTONWOOD - 4.24 MHW ..1111, 12.7 OP OF BANK 97 PLAN - AREA 2 CO LL: co 2. SCALE: 1" =20' CONTOUR INTERVAL = 1 FOR VEGETATED GEOGRID CONSTRUCTION SEE SHEET LS500 PROPOSAL: 'RIVERBANK STABILIZATION AT 7 LOCATIONS DATUM: USGS MSL Z, MI tit 0 z IN: DUWAMISH RIVER AT: TUKWILA, WA COUNTY OF: KING STATE: WASHINGTON APPL BY: BOEING DEFENSE & SPACE GROUF PAGE: 4 OF 17 DATE: 06.14.96 9 +07.99 BASELINE SET HUB & TACK 13. GENERAL NOTE: 13.3 1. 100 YR FLOOD = EL. +8.3 k k co' —9.9 X 12" WILLOW 5.10 OHW —4.8 x 4.24 MHW ASPH 13.7 N TOP OF BANK TOP OF BANK 13.3 X 12.5 5 +79.63 BASELINE REBAR WITH RED CONTROL CAP 13.1 X C8 ��� r> >,!Iii t.Uam'. rieininrP. v- Ottii4 Ot ‘‘‘ k, -4,444.■ AAA I' 1 11.1 MHHW TOP OF BANK 12" WILLOW 0 2 +00.00 BASELINE PK NAIL WITH CONTROL FLASHER 13.2 PATH 13.1 P_AN - AREA 3 SCALE: 11 =20' CONTOUR INTERVAL = 1 DATUM: USGS MSL FOR VEGETATED GEOGRID CONSTRUCTION DETAIL, SEE SHEET LS500 FOR SEEDED AREAS DETAILS SEE SHEET L5500 o3 X -10.0 co -10.1 et,(• , -Z= olflo PROPOSAL: RIVERBANK STABILIZATION AT 7 LOCATIONS. IN: DUWAMISH RIVER AT: TUKWILA, WA COUNTY OF: KING STATE: WASHINGTON APPL BY: BOEING DEFENSE & SPACE GROUP PAGE: 5 OF 17 DATE: 06.14.96 rt".ir arts P,S.r, :ltn,.!mG57j!'J,o-.'`_, Y`'t SAiMISIV*r °,, Otr.3 k z ~w' 6 00 CO C , W - f'- • u W o 2 g J cn W d Z Z0• uj U � (0 • I-' ,= W' LI o, O 5-92 w Z; z 4,24 MHW 5.10 OHW X -6.7 TOP OF BANK NEW TOP OF BANK 9 +71.60 10.5 10.4 9 +07.99 BASELINE HUB & TACK PAN•- AREA 4 TOP OF BANK .75' 5 +79.63 BASELINE REBAR WITH RED CONTROL CAP SCALE: 1" =20' CONTOUR INTERVAL = 1 DATUM: USGS MSL A FOR VEGETATED GEOGRID CONSTRUCTION DETAIL SEE SHEET LS500 FOR SEEDED AREAS DETAILS SEE SHEET LS500 FOR PATH RELOCATION 'DETAILS SEE' SHEET LS80 —4.6 X • PROPOSAL: RIVERBANK STABILIZATION AT 7 LOCATIONS IN: DUWAMISH RIVER AT: TUKWILA, WA COUNTY OF: KING STATE: WASHINGTON APPL BY: BOEING DEFENSE & SPACE GROUP PAGE: 6 OF 17 DATE: 06.14.96 Mms, ,,�IaKr4+ lftAl ,, !'r.inz.CroP "m.plirrsl: "a 1rsm; ! ! n+�rr a * �r crr rrwr7m :;uxreatrs?: CONCRETE PIPE WITH CAP I.E. =1.19 . TOP OF BANK NEW TOP OF BANK TOP OF BANK 9.9 -6,3 X / X -5.3 X -8.6 -5.6 w , D 0 3.8l� 1��7 ' y -42.4ar4Ve.i. 9.6 ArOviscriniuorib■ Ab, Am`lr41•FNer 9.8 WASP ■a't 41*-Zit'ZiNIPairdlib■ Am/ 41.� ' /`per +���� 4.24 MHW 5.10 OHW TOP OF BANK C; 12" WILLOW 10 +82.60 13 +37.71 BASELINE PK NAIL WITH CONTROL FLASHER • 10 +67.60 10 +36.60 9 +07.99 BASELINE HUB & TACK PLAN - AREA 5 SCALE: 1" =20' CONTOUR INTERVAL = 1 DATUM: USGS MSL FOR VEGETATED GEOGRID CONSTRUCTION DETAIL SEE SHEET LS500 FOR SEEDED AREAS DETAILS SEE SHEET LS500 FOR PATH RELOCATION • DETAILS SEE SHEET LS80 x N. x - �s, X -5.3 C -z-0 (f0 PROPOSAL: • RIVERBANK STABILIZATION AT 7 LOCATIONS IN: DUWAMISH RIVER AT: TUKWILA, WA COUNTY OF: KING STATE: WASHINGTON APPL BY: BOEING DEFENSE & SPACE GROUP. PAGE: 7 OF 17 DATE: 06.14.96 z _ ~. W. .0 0: w =• � LL. W 0. Q u. <t; H N�. I-w z� Z O: w w. 2 .0 0E-` ..w W Z'. .0 O •z TOP OF BANK X -3.6 23 +02.79 BASELINE PK NAIL WITH 11 CONTROL FLASHER 10. -3.7 X -3.0 1.1 -2.8 X -3.9 x 11.4 3�_ 2 MSS 1.0 DGE 12.0 13 +67.20 1.2 5 10.9 4.24 MHW OHW TOP OF BANK 13 +37.71 BASELINE PK NAIL WITH CONTROL FLASHER 9 +07.99 .BASELINE HUB & TACK PLAN - AREA 6 SCALE: 1„ =20' CONTOUR INTERVAL = 1 DATUM: USGS MSL FOR VEGETATED GEOGRID CONSTRUCTION DETAIL SEE SHEET LS500 FOR SEEDED AREAS DETAILS SEE SHEET LS500 • /FOR PATH RELOCATION DETAILS 3\ SEE SHEET LS80 1t -Z- Offlo PROPOSAL: RIVERBANK STABILIZATION AT 7 LOCATIONS IN: DUWAMISH RIVER AT: TUKWILA, WA COUNTY OF: KING STATE: WASHINGTON APPL BY: BOEING DEFENSE & SPACE GROUI PAGE: 8 OF 17 DATE: 06.14.96 23 +02.79 BASELINE PK NAIL WITH CONTROL FLASHER -8.9 • 6" DECIDUOUS TOP OF BANK 10.6 4.2 7.8 9.9 X -12.0 X -11.8 frjsy -9.8 X -11.1 /ei X -11.9 -7.9 x X -11.7 X -11.E 1 0 -3.5X " 221-77.10 11.5 46, 44.24 MHW OHW o.o ARMOR ROCKS ��� %r�;• 11.0 �Qj� OA 1.5 16" WILLOW Vh C 799' 22 +66.60 \ NX -7.2 l4. 22 +57.30 X -12.0 -11.0 13 +37.71 BASELINE PK NAIL WITH CONTROL FLASHER PAN. - AREA 7 SCALE: 1" =20' CONTOUR INTERVAL = 1 DATUM: USGS MSL FOR VEGETATED GEOGRID CONSTRUCTION DETAIL SEE SHEET LS500 • FOR SEEDED AREAS DETAILS SEE SHEET LS500 PROPOSAL: RIVERBANK 0 ' STABILIZATION AT 7 LOCATIONS IN: DUWAMISH RIVER AT: TUKWILA, WA COUNTY OF: KING STATE: WASHINGTON APPL BY: BOEING DEFENSE & SPACE GROUP PAGE: 9 OF 17 DATE: 06.14.96 k?. ....'• r^sttt +auer•:msse+ r..•.,rsh, rrsvq. rsrsr'm x aer!montIctxn r mom" '.- ANII C?1� mattm < .. I=- Z 00 CO 0: w uj W= W • OO g LL <. =a: W I- O? Z F- ▪ LIJi , • 0 :O 0 I— 'W W • Vf LI- wZ 0 WE H 4' O z 4. GRAVEL MIN _ -EWIN-Q BAT '•0 Cr") 0 1-113—St-R—E-4 —sElcira I I 1 DOW—NSTRIAM — SEE SECTION B EL +8.3 _ APPROX HIGH WATER LEVEL --"SL OHVY +57113 - - - - - - - - -7 - - - - - - - - - - - - - - QUARRY -SPAM- PRO ------------- ■■■• - v sEA — — — -IT T 6fr- EXSI N oo O'-6" MIN, TYP APPROXIMATE LIMITS - OF EX CAV-A-Ti CT■1 V MLLW SECTION - AREA 1 SCALE: 1"=4' HORIZ 1" =4' VERT C80 C500 z a • z w 6 g (-) o 14 •co ° (/) LU 13 12 w 0. 11 10 ILL " (L.) 9 8. i-0. 7 D 6 5 0)- 4 w (.) 3 , u_ 2 icg co: 1 0 17 0 z -1 —2 —3 — 4 —5 — 6 PROPOSAL: RIVERBANK STABILIZATION AT 7 LOCATIONS IN: DUWAMISH RIVER AT: TUKWILA, WA COUNTY OF: KING STATE: WASHINGTON APPL BY: BOEING DEFENSE & SPACE GROU! PAGE: 10 OF 17 DATE: 06.14.96 , 1,13.!PWRA UPSTREAM - SEE SECTION F _ DOWNSTREAM - SEE SECTION G - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - EXISTING BANK • - - = EL +8.3 V APPROX HIGH WATER LEVEL UHN-7= _ _ _QUARRY _ SPALLS PROPOSED BANK • _____APPROXIMAM UMI5_ _ _ _ _ _ _ OF EXCAVATION SECTION - AREA 2 SCALE: 1" =4' HORIZ 1" =4' VERT c8,1s500. _ - - - "■•■._ ■•■■• •■• ■••■• .■■• •••■ _ _ _ A pp (;cot; - 0 1 II o 14 13 12 11 10 9 z z W. 6 -J c-) .00 0) 1.1- w 0 < 3 z 8 o LU w 7 2 6 o — 5 u 4 . 3 cy , Z LLI 2 0 -- 1 0 0 — 1 — 2 — 3 — 4 — 5 — 6 PROPOSAL: RIVERBANK STABILIZATION AT 7 LOCATIONS IN: DUWAMISH RIVER AT: TUKWILA, WA COUNTY OF: KING STATE: WASHINGTON APPL BY: BOEING DEFENSE & SPACE GROUI PAGE: 11 OF 17 DATE: 06.14.96 14 13 12 1.1 10 9 8 7 6 5 4 3 2 1 0 - 1 -2 -3 -4 - 5 - 6 _ _ UPSTREAM - SEE SECTION A ___ _ _PI-R-EAM ----- SEE-SECT-10E3 --- _______ _ _ _ _YR_FLOOD— - - — - — _ _ _ _ _ v_1=9CtEL +8.3 V APPROX HIGH WATER LEVEL .21=CEMIN. EXISTING BANK PR-01-50YEEBANK ww. •■■ mw. oom■ omw ■■• •■•■ •w•• •MW ■ow■o mwo .wm wwo■ w■ mow ■•■ mow o■ •■■im ■mow =we ■wwww APPROXIMATE LIMITS OF EXCAVATION - • "7-77 M_ — v FAN SEA LVE L — sowommwo i•e) 0 SECTION - AREA 3 SCALE: 1"=4' HORIZ 1"=4' VERT • (1) C81 C501 A (!caiiii, 5tC-Z - PROPOSAL: RIVERBANK STABILIZATION AT 7 LOCATIONS IN: DUWAMISH RIVER AT: TUKWILA, WA COUNTY OF: KING STATE: WASHINGTON APPL BY: BOEING DEFENSE & SPACE GROU PAGE: 12 OF 17 DATE: 06.14.96 .4WWP:Kt..X79, 1:M• .r"M55.7ir 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 —1 —2 —3 —4 —5 6 IF.: re11 I) 0 cn u) 11.1 — - L. im 0 ci a 21-On MIN TYP I- al 100 YR Z F. "ss (GRAVEL MIN 1- 0 -- , z 1- e...----- UPSTREAM - SEE SECTION A sz APPROX HIGH WATER LEW - N\ DOWNSTREAM - SEE SECTION 8 . 0 D (;) 0 .9-: OHW=EL +5,10 in F- ill id <7...i- L..s.__ - - — - - — - - — - _ — - - — _ - — _ - - F 0 , \\_ ITOPOSECIBANK LL..,_ r-zo EXISTING BANK - • QUARRY 515AIIS ARMOR — - - - -------- - - MSL z • • - x (0; APPROXIMATE LIMITS — oracFaria - - - — - — - - — - — 0'-6" MIN TYP +1 ••■••■••• 04_ SECTION - AREA 4 SCALE: 1"=4' rtmwswitrreanw-~a4romP,MtehtitZWM31.17,t4rATVgialtIIPM551551(A521**PtftY,M.5511W0411.M7R,MVOIMM,,,V,M115.5t.rd.., • '5, • '1 • C82 C502 ----r---- A • - a - o ao PROPOSAL: RIVERBANK STABILIZATION AT 7 LOCATIONS IN: DUWAMISH RIVER AT: TUKWILA, WA COUNTY OF: KING STATE: WASHINGTON APPL BY: BOEING DEFENSE & SPACE GROl PAGE: 13 OF 17 DATE: 06.14.9( ' CYA, 0-,‘,0ex.**FngfP-MP9V.:11 I IRSIREAM - SFF SE 010-N DOWNSTREAM - SEE SECTION F 4"GRAVEL MIN PROPOSED BANK EXISTING BANK QUARRY SHALLS 160 ELOOD-AL _sz APPROX HIGH WATER LEVEL OHW=EL +5.10 INSTALL NEW PIPE & CAP TO MATCH SLOPE OF — - - — — - — - - EXIST 187ITIA CONC PIPE EXTEND CAP — -TO -DAYLIGHT-AT - _SAKE_ SLOP_E_ _ _ _ _M•■••••■ ARMOR- - ROCK _ - - ..., •■■ •••••••■•••• ■•• 2.........= •■•• ■■•■•• .■ e■D •■•■••■• .... .,... "S.... R.. ..,... ' .......,. .... ■■•••■•%■ 1••■ ■■ ....■ ...■ ■••• ■■•■•• ... ... '.....*.....,..... ..,,. ...' ...... ..■ ■■• ■•■••■,.... ...■ ....■ ..M .■ ...... --APPRTOWATE. TWITS- L — — -QUARRY- MILW -WALLS — - - - - SECTION - AREA 5 SCALE: 1" =4' TOE - ROCK- :14 .13 12 11 10 9 8 7 6 5 4 3 2 1 0 —1 —2 —3 —4 . —5 —6 C82 C502 PROPOSAL: RIVERBANK STABILIZATION AT 7 LOCATIONS IN: DUWAMISH RIVER AT: TUKWILA, WA COUNTY OF: KING STATE: WASHINGTON APPL BY: BOEING DEFENSE & SPACE GROU PAGE: 14 OF 17 DATE: 06.14.96 \ PSTREAM - SEE SECTION A DOWNSTREAM - SEE SECTION B sz 100 YR FLOOD=EL +8.3 APPROX HIGH WATER LEVEL PROPOSED BANK Q-U-A R-R APPROXIMATE LIMITS OF EXCAVATIO1T .__ TOE —ROOK a OHW=EL +5.10 EXISTING BANK ... ■■•■•■• .■■"' .......,, ........""-.......... ...■. ... ..■., .■■ . .......■•■• •■• ■■• ■•■••• •■• ■ •••••■•■•■•• ■•• •■ ••■••■•7 .■ ■■• ...■ ••••____ , _. • -.... -..; •Mn e..I 10. ■IM ■■■••■• MM• .■ ■••■•• =1:7'AM ..../.1■ ■In W■M.,••• •■• .... ,.. .... ...... .......... •••■ ... ,. .... .1.... ...•••■ ..... • .,... ■.• ...■• •••••• ■■••• ••■•••■ ■•■ ■■• , ••■• ••••■ ...6. .... ■■■••••■ .... ■• ••••■ ■■• ■.. ■■■ •■••■• ■••■ •■ ■■••• .... ... •■■ :LI ..... ■ ...0 •■■•■■• ... ■;•.......M....,.....z •■•••■•■ ■ .... ..■.. ■.. .... ..• ■■. ...... -------------------------------------------- - ■.. •/,..y .■ .... ■••■••■ ■ SECTION - AREA 6 SCALE: 1"=4' HORIZ 1" =4' VERT • rTh C83 C503 /Off • MILLW A (;c.kko C -2. - 01«0 PROPOSAL: RIVERBANK STABILIZATION AT 7 LOCATIONS Z ce . 6n: 00 14 : co w • ILI .J 1- ' CO u.• 12 ;o 11 2 10 ma: 9 . LI-Im 8 I- 0' 7 z 111 6 2 a : (0 5 •o - ,0 )- 4 Ili a .3 o• o 2 . z, _ 1 17: ; o 0 z - 1 - 2 - 3 - 4 - 5 -6 IN: DUWAMISH RIVER AT: TUKWILA, WA COUNTY OF: KING STATE: WASHINGTON APPL BY: BOEING DEFENSE & SPACE GROU PAGE: 15 OF 17 ' DATE: 06.14.9( - -^.... __...._..--.. — — — 1.. - - — - - — - — - — - — - — — — — — - - UPSTREAM - SEE SECTION D DOWNSTREAM - SEE SECTION E N sa 100 YR FLOOD =EL +8.3 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ PRQ P 05EL a_AN K APPROX HIGH WATER LEVEL 4" GRAVEL MIN - - - -APPROXIMATE- L-IMI OF EXCAVATION -TOE- - ROCK QUARRY - - - PALL . - - -_-----____ "=EL +5.10 . EXISTING BANK ks- • mEAN • - - mILLW -------------------------------------------- _____________________________________z._.. SECTION - AREA 7 SCALE: 1" =4' HORIZ 1" =4' VERT • • a..a1.111, rF C8,31903 (7C416 k Otaa PROPOSAL: RIVERBANK STABILIZATION AT 7 LOCATIONS 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 -1 - 2 - 3 - 4 -5 -6 IN: DUWAMISH RIVER AT: TUKWILA, WA COUNTY OF: KING STATE: WASHINGTON AP PL BY: BOEING DEFENSE & SPACE GROU PAGE: 16 OF 17 DATE: 06.14.9E EXISTING/ 1 RELOCATED CINDER JOGGING TRAIL VARIES SEE PLAN RESTORE LAWN AND REPAIR /ADJUST IRRIGATION IN THIS AREA (TYPICAL). INSTALL TOPSOIL PER 12500 TOP OF SLOPE =TOP OF VEGETATED GEOGRID UVE CUTTINGS /BRUSH LAYERING (1YP.) SEE COIR GEOTEXTILE FABRIC RIP -RAP SLOPE PROTECTION, SEE SHEETS C80 -83 & C500 -503 ORDINARY HIGH WATER MARK BRUSH LAYERING Lssoo PLANTING DETAIL TO? NATNE RIVERBANK SOILS SOIL BACKF1LL MATERIAL TOP OF RIP -RAP =TOE OF VEGETATED GEOGRID (REV.-7.0) (--A VEGETATED GEOGRID TYPICAL SECTION isepLis500 NOT TO SCALE RIVERBED i4idp ( ;cdio.. IL z - o c cro PROPOSAL: RIVERBANK STABILIZATION AT 7 LOCATIONS IN: DUWAMISH RIVER AT: TUKWILA, WA COUNTY OF: KING STATE: WASHINGTON APPL BY: BOEING DEFENSE & SPACE GROI PAGE: 17 OF 17 DATE: 06.14.9E A F F I D A V I T O F D I S T R I B U T I O N I , Sq LV 1 A 1 e AMAILL4;0 hereby declare that: fl Notice of Public Hearing fl Notice of Public Meeting O Board of Adjustment Agenda Packet Q Board of Appeals Agenda Packet Q Planning Commission Agenda Packet O Short Subdivision Agenda Packet O Notice of Application for Shoreline Management Permit fl Shoreline Management Permit was mailed to each of the following addresses on -7- 2-5--9(0 O Determination of Non - significance 0 Mitigated Determination of Nonsignificance 0 Determination of Significance and Scoping Notice )(Notice of Action 0 Of ficial Notice O Other, O Other_ E St-1 EA-aT.) Name of Pro j ect NWI\M IS I-i �lV'F -�iZ 4t i.gnature ;IN File Number LC1 10 - 0041 STNEA142,1 1pr-S • z • < _ f-' Wet. 00: • U0i CO w; •WI CO •LL' w o °. H , • 'Jo siz • • fa • D I- z; O :z City of Tukwila la John W. Rants, Mayor Department of Community Development Steve Lancaster, Director July 22, 1996 EXEMPTION FROM SHORELINE MANAGEMENT ACT SUBSTANTIAL DEVELOPMENT PERMIT REQUIREMENT Terry Bennett Permits Administrator Boeing Information and Support Services P.O. Box 3707 Seattle, WA 98124 -2207 Dear Mr. Bennett, This letter is to notify you that the proposal by Boeing to undertake stabilization of the west bank of the Duwamish River in the vicinity of South 102nd Street in Tukwila is exempt from the requirement of a substantial development permit because the development falls under WAC 173 -14 -040 (d) Emergency construction necessary to protect property from damage by the elements. Erosion in seven areas is threatening the river trail through the Boeing complex and • posing a potential hazard to pedestrians. The proposed development is consistent with the Policies of the Shoreline Managinent Act and the King County Shoreline Master Program. Sincerely, Steve Lancaster Director, Department of Community Development 6300 Southcenter Boulevard, Suite #100 • Tukwila, Washington 98188 •(206) 431 -3670 • Fax (206) 431-3665 City of Tukwila Department of Community Development 6300 Southcenter Boulevard Tukwila, WA 98188 -2599 lJ U.S. ARMY CORP OF ENGINEERS 4735 East Marginal Way South Seattle, WA 98124 -2255 DUWAMISH INDIAN TRIBE 140 RAINIER AVE S - STE 7 RENTON, WA 98055 -2000 ® MUCKLESHOOT INDIAN TRIBE 39015 172ND AVE SE AUBURN, WA 98092 EPARTMENT OF ECOLOGY SHORELINE PERMIT REVIEW 3190 160TH AVE SE BELLEVUE, WA 98008 75452 VIM o lukF3LAG WOR-YS 600 53kATI-agT5e- E5L- - ST'F. l°° 1 1 A - } % w I L A WA I $ i 2 z i~,. 6 DI 01 O.: co o;, = H wO H.= z I--; f- O z F- = V Zt lb N? .o AWE /NG -017o - l71 -or 701 F96 - vvs9 June 12, 1996 G- 8921 -J K -96 -001 Information & Support Services P.O. Box 3707 Seattle, WA 98124 -2207 Mr. Steve Lancaster Director Department of Community Development City of Tukwila 6300 Southcenter Boulevard Tukwila, WA 98188 Dear Sir: Subject: Duwamish West Riverbank Stabilization Vicinity of S1O2nd Street L -ooh/ RECEIVED CITY OF TUKWILA JUN 1 7 1996 PERMIT CENTER Boeing Defense & Space Group hereby requests an exemption from the City Shorelines Permit because our project is for streambank maintenance and trail protection from bank erosion in several areas recently damaged by high river flows. Involved is streambank stabilization in seven locations and relocation of 220 lineal feet of path at two locations. Sincerely, -/er)A-e/ Terry Bennett Permits Administrator • City of Tuk.,iila Central Permit System - Engineering Division 6300 Southcenter Blvd., Suite #100, Tukwila, WA 98188 Applict,... n # X96 -005 Phone: (206) 433 -0179 UTILITY PERMIT APPLICATION Site Address: 10500 West Marginal PlaceS(Building 9 -150) v�r►r�,v� Name of Project: Duwamish West Riverbank Stabilization Property Owner: Boeing Defense & Space Group Street Address: P.O. Box 3707, M/S 46 -87 Engineer: Boeing Defense & Space Group Street Address: P.O. Box 3707, M/S 46 =87 Contractor: Street Address: (Terry Bennett) (Terry Bennett) Phone No.: City /State/Zip: Phone No.: City /State /Zip: Phone No.: City /State /Zip: 544 -2975. Seattle, WA 98124' -.2207 544 -2975 Seattle, WA 98124 -2207 King Cty Assessor Acct #: ON a 30,1' T50 Contractor's License #: Exp. Date: • Channelization/Striping /Signing Curb Cut/Access /Sidewalk Fire Loop /Hydr. (main to vault) - No.: Sizes: O Flood Zone Control K7 Hauling l Land Altering 5' O cubic yards ❑ Landscape Irrigation ❑ Moving an Oversized Load Est. start/end times: Date: ❑ Sanitary Side Sewer- No.: ❑ Sewer Main Extension„ ❑ Private ❑ Public (Storm Drainage ❑ Street Use ❑ Water Main Extension ❑Private ❑ Public ❑ Water Meter / Exempt: - No.: Sizes' Deduct ❑ Water Only ❑. ❑ Water Meter / Permanent - No.: Sizes: _❑'.Water Meter/ Temporary: -;No.: Sizes: 'T.: Estimated quantity* Schedule: ❑ Other: y•,'_ Street Address: ❑ Water ' ❑ Sewer ❑ Multiple - Family Dwelling No. of Units: ❑ Metro ❑ Standby • ❑ Single - Family Residential ❑ Duplex ❑ Apartments ❑ Triplex ❑ Condominiums ❑ CommerciaVlndustrial ❑ Hotel ❑ Motel ❑ Off ice ❑ Retail Phone No.: City /State/Zip: -Phone • No.: City /State/Zip: RECEIVW* Jury 171°I96 0 Other: TUKWILA a>I tRt IG WORKS `School%College /University . ®'Other: Riverbank Stabilization ❑ Warehouse ❑ Manufacturing ❑ Church ❑ Hospital n vim`: > >`> ❑ New Building Square ":�... - ....................... Footage: King County Assessor's valuation of existing ❑ Remodel/ Square footage of original building space: N/A Addition Square footage of additional building space: N/A structures: $ N/A Valuation of work to be done: $ 19.1, 000 <1 :HEREBY CERTIF...Y:.THAT.f HAYS RE �!;. IS::APP..I 'ICATION: .::'...: r Applicant /Authorized • gent Signature: Print Name: • Date: vY Terry Rennett Phone: Contact Person (print name): Terry Bennett Address: JUN 1 7 1996 544 -2975 PERMIT CENTER Phone: 544 -2975 Date Application Accepted: - l 9 _ Q (/2 Date Application Expires: AltiVIMP 04/22/92 MENINESSIONISMISI z w 00 coo, w= J i`• w LL? '1a =w H- _. z� zF- O • "•zf-. O E- wW h- -- u-O Lii Z` i I O~ z• FACIL 1TIES L IRRARY E- t_COp <Ca.' SEP 2 31 952 REPORT OF PHASE II RIVER BANK STABILIZATION STUDY BOEING DEVELOPMENTAL CENTER SEATTLE, WASHINGTON FOR THE BOEING MILITARY AIRPLANE COMPANY 00695- 348 -016 NOVEMBER 24, 1986 Dames & Moore RECEP4170 , 'JUN 2 41996 TUKW 1, PUBLIC Z I f—; i.� Z' re 2 6 J U O W w WI L W O` u_ Id w; I 1- O Z w W; =W -0 Z w co U =t 0 ~` ,Z Dames & Moore Boeing Military Airplane Company P.O. Box 3707, M/S 46 -87 Seattle, Washington 98124 -2207 rte*, Ste. 500, Northgate Exec. .i. 155 N.E. 100th Street P.O. Box 75981 Seattle, WA 98125 -0981 (206) 523-0560 November 24, 1986 Attention: Mr. L.F. Boulanger, P.E. Plant Engineering Manager, Facilities Gentlemen: Report of Phase II River Bank Stabilization Study Boeing Developmental Center Seattle, Washington INTRODUCTION This report presents the results of our stabilization study of river bank areas in the vicinity of the Oxbow parking lot at the Boeing Developmental Center in Seattle, Washington. The scope of services for this study is outlined in our proposal dated April 28, 1986. Authoriza- tion was provided by your Work Order Request dated May 6, 1986. This Phase II study encompasses about 2,300 lineal feet of shoreline on the west bank and about 600 lineal feet on the east bank of the Duwamish River. Our initial Phase I study covered about 800 lineal feet of river bank along the west shore adjacent to the Employees Activity Center which is currently under construction. The river bank areas for both phases of this evaluation are shown on the Vicinity Map, Plate 1, and Location Plan, Plate 2. Results of our earlier study were submitted in our report dated November 10, 1986 and addendum dated November 24, 1986. The river banks in the Phase II areas have undergone varying degrees of erosion. Some bank sections exhibit little or no erosion due to rela- tively flat bank slopes, vegetative cover, artificial protection such as Z , Q �- Z` 00 to 0:, w= wO. = Chi F_ W Z �. I- O: Z F-; U � 0� 1-; V; O; • z': Z Dames & Moore Boeing Military Airplane Company November 24, 1986 Page 2 rock riprap or concrete rubble, or some combination of these protective conditions. In a few relatively unprotected areas, erosion has resulted in over - steepening of the river bank, thereby inducing unstable con- ditions, progressive slope failures and loss of ground. Overall, the river banks in the Phase II area are in much better condition than the banks studied in Phase I. The Phase II banks typically contain more vegetative cover and artificial protection while exhibiting less evidence of recent erosion. Soil types in both areas are similar. SCOPE The purpose of this study is to evaluate the extent and severity of the river bank erosion and provide recommendations for bank stabiliza- tion. To accomplish these objectives, our scope of services includes: 1. Field reconnaissance of the river bank to identify the extent of erosion and bank instability. An engineer from our staff observed and noted eroded areas, obtained representative soil samples for laboratory testing, and photographed portions of the river bank for use during our office evaluations. 2. Laboratory gradation tests on samples recovered from the field. Direct shear tests were performed on samples from the Phase I area to obtain representative strength parameters for area soils. Results of these tests were presented in our November 10 report. 3. Cross sections of the river bank at about 50 -foot intervals. Surveys were performed by Hammond, Collier & Wade - Livingstone Associates, Inc., under subcontract to Dames & Moore. 4. A brief literature search to gather relevant information con- cerning bank stabilization techniques. 5. Discussions with representatives of Ring County Shoreline Management, Washington State Department of Fisheries, and the z w • 6 OO U = J �. co w. wwQ0 LL -J Z a I•- W. Z N; I- O. Z 1-* LLI W O • N' 0 H; w La 1-• U,. LL O H = O I- Z Dames & Moore Boeing Military Airplane Company November 24, 1986 Page 3 U.S. Army Corps of Engineers to identify potential constraints Z associated with stabilization work in the area. W, 6. A report summarizing our findings and recommendations for R U: appropriate stabilization techniques. 0 O N'0i co SITE DESCRIPTION J H, u_: W O• General: Field reconnaissance and laboratory testing of recovered q�: samples indicate that the surficial soils along the river bank in the u_4( Phase II area are primarily sandy silt and sand. Heavy brush and black- W berry cover is often present along undisturbed portions of the river =- I-O bank, although some barren ground was observed primarily in eroded or W recently failed bank areas. Other portions of the river bank within the U • 0'; study area have been protected with riprap or concrete rubble that has O co` O F_ frequently been placed in a somewhat random manner. Brief descriptions W W V of site conditions and erosion features along the alignment are provided u_.0 1 in the following paragraphs. Cross section locations are shown on LLjN Plate 2. Plotted cross sections of the river bank are included on Plates 3 through 12. All elevations in this study correspond to the Mean Z. Sea Level (MSL) datum. Elevation 0.0, MSL corresponds to Elevation +6.6, Mean Lower Low Water (MLLW) in the study area. Related photographs are presented on Plates 13 and 14. Soil Conditions: The soils along the river bank in the Phase II area consist mainly of fine sand with a variable silt content and sandy silt. The gradation curves shown on Plate 15 are representative of the gradation range of the river bank soils in the study area. Soils within about 0.5 feet of the surface often contain roots and organic matter. The soils appear to be in a loose to medium dense and medium stiff con- dition, although near - surface soils in eroded areas are in a looser state. The fine grained nature of these sediments and low to moderate densities renders them very susceptible to erosion from wind and water forces if left unprotected. `Dames & Moore Boeing Military Airplane Company November 24, 1986 Page 4 River Characteristics : The Duwamish River is a relatively large, slow - moving river in the study area. It ranges in width from about 200 to 400 feet, becoming wider as it flows to the northwest through the study area. Probable maximum river depths near the site are about 15 to 20 feet during peak river flow. The river is about 5 feet deeper imme- diately down stream of the Oxbow Bridge. The depth variation in the Duwamish River near the site is influenced by both tidal effects and river flow conditions. River flow is known to vary widely in the area, from about 200 cubic feet per second (cfs) to 12,000 cfs. Tidal effects will have little influence on river depths in the study area during periods of high river flow and a large influence during periods of low river flow. The maximum high water mark is expected to be around Elevation +7. The low water mark could conceivably reach near Elevation -8, although this condition could occur only during infrequent periods of low river flow in combination with extreme low tides. Information pro- vided by the Army Corps of Engineers indicates that average current velo- cities are about 5 feet per second. West Bank Conditions: The condition of the west river bank ranges from fairly well protected in most areas to severely eroded in a few sec- tions. River bank slopes at Station W 10 +00 are relatively flat at about 2 to 1 (horizontal to vertical) and contain heavy brush and blackberry cover. The top of the bank is at about Elevation +13. Bank slopes between Stations W 10 +50 to W 12 +50 steepen to as much as 1/2 to 1 above Elevations 0 to +5. Lower bank slopes are much flatter at near 4 to 1. The upper bank slopes generally contain heavy brush and blackberry cover, except for a 30- to 40 -foot long section just south of Station W 12 +50 where recent erosion has left the slopes primarily bare (see Plate 13) . North of Station W 12 +50, bank heights diminish somewhat with the top of bank at about +9. Upper bank slopes are near 1 to 1 or flatter through Station W 14 +50. Some bank protection exists below the high water mark between Stations W 12 +50 and W 15 +00, consisting of concrete rubble and riprap. Z Z: u6D U O` U C W =• J H,: 0 w =• 0 _ Z° ▪ j` o; O , O F-- w W .1--- I. - O z•. flames & Moore .Boeing Military Airplane Company November 24, 1986 Page 5 Locally steep upper banks with slopes of 1/2 to 1 exist near Station W 15 +00. Lower bank slopes continue at 3 to 1 or flatter. The lower bank slope forms a relatively flat, marshy area below the high water mark. Both upper and lower bank slopes are well vegetated. Little arti- ficial slope protection exists from Station W 15 +00 to W 17 +00. Bank erosion becomes more apparent north of Station W 16 +25 to about Station W 17 +50 (see Plate 13). Upper bank slopes above Elevation +3 in this sec- tion are as steep as 3/4 to 1. Lower bank slopes are at about 4 to 1. Large pieces of concrete rubble exist near Station W 17 +25 in a steep upper bank zone. Bank slopes appear fairly stable from Stations W 17 +50 to W 20 +50, with inclinations above Elevation 0 of about 2 to 1. Lower bank slopes are 2 to 1 and flatter. Intermittent bank protection consisting of concrete rubble exists throughout this area. Upper bank slopes begin to steepen to about 1/2 to 1 near the south side of the Oxbow Bridge at Station W 21 +00. The bank in this area con- tains scattered pieces of broken concrete. Upper bank slopes immediately below the bridge are relatively bare of vegetation. The bank appears fairly stable north of the Oxbow Bridge from Station W 21 +50 to W 25 +00 (see Plate 13). The bank through this stretch appears fairly well protected with rock riprap. Both above and below water bank slopes are on the order of 2 to 1 or slightly flatter. Bank erosion becomes more apparent between Stations W 25 +00 to W 25 +75 (see Plate 13). Riprap protection is sparse in this area, and upper bank slopes are as steep as 1/3 to 1. From Station W 25 +75 to W 27 +25, bank slopes are relatively flat and the existing riprap appears to be providing adequate protection (see Plate 14). North of Station W 27 +25 to about Station W 28 +50 (see Plate 14), the bank is partially unprotected, except for the heavy grass and brush cover, and upper bank slopes are as steep as 3/4 to 1. Lower bank slopes are inclined at about z rt 6 J 0� 00 0)0, - F- LL w • }}0 g J ur¢; �w z �. z 0' w j U 0 O 0 - 2w 0, ti.l z' U 2 0 z Dames & Moore Boeing Military Airplane Company November 24, 1986 Page 6 5 to 1 or flatter. Little evidence of recent erosion exists in this area. Between Stations W 28 + 75 and W 29 +50, the upper bank slopes are inclined at about 1 1/2 to 1 and are protected by rock riprap. North of Station W 29 +50 to the end.of the Phase II area at Station W 33 +00, the bank slopes are free of riprap or other artificial protec- tion and locally steep in some areas. For example, upper bank slopes of 1/4 to 1 were measured at Station W 31 +40 (see Plate 14). The localized steep zones often exhibit evidence of recent erosion. Uneroded areas typically contain a heavy blackberry, brush, and grass cover. East Bank Conditions: The Phase II study of the east bank of the Duwamish River began at the north end of a concrete dock retaining wall at Station E 2 +00, about 200 feet north of the Oxbow Bridge. The bank slopes are protected from this point north to about Station E 3 +50 by large pieces of broken concrete (see Plate 14). Upper bank slopes in this section range from 1 to 1 to about 2 1/2 to 1. A tide gate with a protective wood bulkhead exists near Station E 3 +80. The banks are rela- tively unprotected except for scattered riprap and concrete rubble from about Station E 4 +50 to E 5 +50. Upper bank slopes are inclined at about 1 to 1. North of Station E 5 +50 to the end of the Phase II area at Station E 8 +00, bank slopes are generally covered with a heavy brush and black- berry cover above the high water mark. Scattered riprap and concrete rubble exist near the high water mark throughout this section. Upper bank slopes are inclined at 1 to 1 or flatter throughout most of this area, although locally steeper zones are present from Station E 5 +25 to E 6 +25. The remnants of a system of protective timber groins exist just offshore at frequent intervals north of Station E 5 +00. 'Dames & Moore Boeing Military Airplane Company November 24, 1986 Page 7 No cross sections were taken north of Station E 8 +00 due to the relatively stable bank sections observed. Bank slopes there are rela- tively flat and generally well protected by rock riprap, concrete rubble, or vegetative cover. EROSION ASSESSMENT It is obvious from our field reconnaissance and from review of the survey data that several bank sections in the Phase II area have undergone significant erosion and will continue to do so unless stabilization measures are implemented. Sections of particularly severe erosion include the following: Stations Lineal Feet W 12 +00 - W 12 +50 50 W 16 +25 - W 17 +50 125 W 20 +75 - W 21 +50 75 W 30 +75 - W 32 +25 150 TOTAL 400 Bank areas that we consider as having a moderate potential for ero- sion include: Stations Lineal Feet W 10 +25 - W 12 +00 175 W 14 +75 - W 15 +25 50 W 25 +00 - W 25 +75 75 W 27 +25 - W 28 +50 125 W 29 +75 - W 30 +25 50 W 4 +50 - E 6 +25 175 TOTAL 650 Moderate erosion areas typically include bank slopes that are inclined at 3/4 to 1 or steeper with vegetative cover largely intact and little evidence of recent erosion. Other bank areas not listed above fi.1 . HL.r rr �C +i:.r ".alli]bY'Y'4 JAk'vt..w at( L415a4 .d:6:,'i'.i' '@.' ;UCixaa wPnw.a .S i56 0 Aw4,4ai '1W6?1P1/X- '12ttd:f 2 5s@c Z W J0 0 o Wx: J 0 LL W O` u_ = d- WI 1■• .1— O . ZF-: . •,W �.p ;,O N` Oi — O Uco • • ..Z. James & Moore Boeing Military Airplane Company • November 24, 1986 Page 8 appear to be currently stable, although they may be affected by erosion that is occurring at a slow rate. REVIEW OF STABILIZATION ALTERNATIVES We have conducted a brief literature survey and reviewed past Dames & Moore stabilization projects to assemble a list of applicable protec- tion techniques that may be considered for the Phase II area. A list of references is included immediately following the text of this report. The alternatives identified are discussed below and are summarized on Plate 16. The options can be broadly grouped into five areas, as follows: 1. No action. 2. Relocation or set -back of planned facilities. 3. Slope flattening. 4. Revetments. 5. Bulkheads. No Action: This is not a feasible long -term solution in the Phase II area as erosion will probably continue in several areas and could even- tually affect adjacent structures and facilities. This option may be appropriate in relatively stable river bank areas, but is not recommended where recent and active slope erosion exists or where bank slopes are excessively steep. Relocation or Set -Back of Existing and Planned Facilities: This option would involve a loss of land by erosion for protection of nearby facilities. The amount of land required as a buffer zone would depend on the planned design life of the facilites and projected erosion rates. It is our opinion this option is not viable. Slope Flattening: Reduction of river bank slope inclinations would require minimal construction efforts while providing higher factors of safety with respect to deep- seated or sloughing failures. Revegetation 11: Dames & Moore Boeing Military Airplane Compgny November 24, 1986 Page 9 of the bank slopes would add some protection against continued erosion, although it is unlikely that such protection could be established quickly and thoroughly enough to completely halt erosion. It is more likely that flattened revegetated slopes would merely slow the rate of erosion. This alternative might be appropriate where erosion rates are slow, but is not recommended in active erosion areas or where river bank slopes have recently failed. Revetments: Revetments, or slope facings, would generally require flattening of the slopes to an inclination on the order of 2 to 1 for construction practicality and improvement of overall slope stability. Appropriate slope inclinations can be established by cutting or filling. We anticipate, however, that filling will meet significantly more resistance by the regulatory agencies than cutting. Revetments historically have been constructed of such diverse materials as old tires, burlap bags, riprap, and concrete rubble. Revetments made of these materials are flexible and able to adjust to some deflection or distortion without failing. More rigid revetments may consist of Fabriform mats (proprietary), concrete panels, or intercon- nected concrete blocks such as Armorflex (proprietary). Revetments require a filter layer to allow drainage and reduce hydrostatic pressure build -up, yet prevent fine soil particles from escaping. Filters can be graded soil and rock or may incorporate a geotextile. Revetments are typically low maintenance installations, and can be made more aestheti- cally and environmentally acceptable by establishing local vegetation on the sloping face. We believe a riprap revetment represents one of the better alternatives for mitigating river bank erosion in the project area. Bulkheads: Bulkheads are typically used in relatively severe situations where wave heights are high, damage potential is large, or land is not available for inclined slopes. Typical bulkhead installations z HZ rt g; 00 W= J �O W u.= Ell CI _' I- I— O. Z W Lu O O co WW H U. O. 111 N. O Z IL. Imo.. Boeing Military Airplane Company November 24, 1986 Page 10 Dames & Moore Wit: include soldier piles and timber lagging, steel sheet piles, concrete bin walls, reinforced earth walls, and gabions. Bulkheads are generally more expensive to construct than other types of bank protection. Since bulkheads typically have vertical faces for construction ease, wave reflections are maximized, thereby increasing the potential for over- topping and scour in front of the structure. PROJECT CONSTRAINTS In order to obtain updated information regarding constraints placed ei on shoreline stabilization projects, we contacted representatives of • f three agencies including the Ring County Shoreline Management, the State of Washington Department of Fisheries, and the U.S. Army Corps of Engineers. Pertinent considerations for stabilization of river bank areas pro- vided by Ring County Shoreline Management include: 1. Aesthetics: Restoring the stabilized slopes to near - natural conditions with vegetation. 2. Access: The stabilizing method should allow easy access to the river for fishing and recreation. The Ring County representative with whom we spoke described a recent pilot project for Seattle City Light on the Duwamish River that the County encourages other projects to emulate. That project included graded riprap without a geotextile. A 3 -foot wide horizontal bench was included in the slope just above the maximum high water mark to allow river access. Riprap areas below the maximum high water mark were infilled with pea gravel. The pea gravel is intended to trap fine river sediments and thus allow salt grass or other local vegetation to become established. Soil was placed above the maximum high water mark for establishment of alders and other local vegetation. Merl, Z _ I—: ~ w" Q: 2. 6 UO co w, • CO w =: J F..: w O u_ ?: = C1; • w Z�. �O Z 1--' ▪ D Cl' ON u W± 1- U' u_F= O: • 0- H H!: Z 1 tt' t Aft gal Dames & Moore Tot- Boeing Military Airplane Company November 24, 1986 Page 11 The Washington Department of Fisheries provided the following cri- teria for design and construction of revetments or bulkheads: 1. For sloping revetments flatter than 1.5 to 1, the revetment must intersect the beach at or shoreward of Elevation 0.0. 2. For sloping revetments or bulkheads steeper than 1.5 to 1, the revetment /bulkhead must intersect the beach at or shoreward of Elevation +2.4. The Department of Fisheries representative also stated that construction cannot be scheduled during the period of April 1 to June 15, due to the seasonal juvenile salmon migration. A state hydraulic project permit will also be required for any proposed work, whether new construction or maintenance. The Corps of Engineers indicated that small stabilization projects can fit under their nationwide permit program already in place if the following criteria are met: 1. 500 feet of bank or less protected, and 2. Placed fill totals less than 1 cubic yard per running foot waterward of mean higher high water. Additionally, bank erosion or loss that has occurred within the past year can be repaired or replaced under the nationwide permit. Projects that do not fit into the above categories will require individual permits. The Corps has no engineering requirements for this type of project unless nearby federal projects are impacted. Dames & Moore Boeing Military Airplane Company November 24, 1986 Page 12 RECOMMENDATIONS Z. Q Based on our review of site conditions, we recommend that the = ~' F-W re following sections of bank in the Phase II area be stabilized. 2 F)' CHO Stations Lineal Feet . to 13 ,, N W; W 12 +00 - W 12 +50 50 W =,. ...11_, W 16 +25 - W 17 +50 125 N u., W 20 +75 - W 21 +50 75 u00 :=?-, W 30 +75 - W 32 +25 150 QQ ~ , TOTAL 400 U)I W, Z N; These sections of bank have undergone significant erosion and are typified Z O by .steep upper slopes and sparse slope covering or protection. U A Other areas where upper bank areas are relatively steep but are at N 'O ` iot- .! least partially protected with vegetation or artifical means are as = U' I- follows: u. 0 LL. Z, Stations Lineal Feet 0 F-: I; W 10 +25 - W 12 +00 175 O Z W 14 +75 - W 15 +25 50 W 25 +00 - W 25 +75 75 W 27 +25 - W 28 +50 125 W 29 +75 - W 30 +25 50 W 4 +50 - E 6 +25 175 TOTAL 650 These banks sections appear marginally stable at the present time and may not require immediate protection. We recommend, however, that these sec- tions be monitored on a yearly basis to observe any future erosion that may occur as bank conditions change with time. The remaining river bank areas are presently stable and do not represent a high risk of erosion, slumping, or failures. Stabilization efforts in these areas may not be necessary or may be deferred due to the Dames & Moore Boeing Military Airplane Company November 24, 1986 Page 13 apparent low erosion rates. We recommend, however, that all river banks throughout the study area be monitored periodically as a basis for eval- uating the effectiveness of rehabilitated areas and to identify other portions of the bank that may require stabilization in the future. In view of the constraints outlined by the agencies contacted during this study, we recommend that the river bank sections that require reha- bilitation be stabilized with a sloping revetment. Sloping revetments appear to be more in keeping with the environmental and aesthetic guide- lines provided by the various agencies, including river access and restoration of a natural appearance to the repaired areas. In addition, properly designed and constructed revetments can provide the long -term protection needed with little or no maintenance for the currents and light wave action present in the Duwamish River. We further recommend that flexible revetments consisting of rock riprap or similar materials be used for this project. Such riprap revetments are common in the Puget Sound area, contractors are familiar with the construction procedures, and necessary materials are available locally. Although we have not completed an economic evaluation to assess the relative cost of various revetment types, we believe that a rock riprap revetment will prove to be the most appropriate alternative. The existing river bank slopes that require stabilization should first be cut back (or filled) to an inclination of 2 to 1 to enhance overall stability. If cutting is not possible, the recommended slope inclination can be established by filling or a combination of cutting and filling, provided approval can be obtained from the permitting agencies. Cut slopes should be cleared of all loose soil and debris, and com- pacted using light compaction equipment. Some fill may be necessary in the cut sections to smooth out local surface irregularities. Areas to be filled should be cleared of all vegetation before filling. Fill should consist of clean imported sand and gravel with less than 5 percent passing z J V. 00 0, N w u. wO g Q. 22,3 H w Z 1- O. Z w w n p, O N: o w W` = ▪ U' O, WC) Z; H ` O ~: - Boeing Military Airplane Company November 24, 1986 Page 14 Dames & Moore the No. 200 sieve. Fill should be placed in lifts with a maximum loose thickness of I foot. Each lift should be compacted to at least 90 per- cent of maximum dry density according to ASTM D -1557. Compaction of fill should also be accomplished using light compaction equipment. Soil exposed in cut areas should be compacted to the recommended 90 percent criteria once the recommended slope inclinations are established. The design and construction of the slopes should be in accordance with the Department of Fisheries criteria outlined previously. An existing jogging trail at the top of the west bank is within several feet of the bank at some locations and may need to be relocated. Slope cuts should be graded gradually into the natural banks surrounding the protected areas to prevent flank erosion. The riprap should extend throughout the zone of significant tidal influence, from at least 1 foot above the high water mark to a reasonable low river level. Accordingly, we recommend that the riprap extend from at least Elevation +8 to at least Elevation -2. Riprap extending to the extreme low river level of about Elevation -8 would be prohibitively expensive and unnecessary due to the infrequent very low water conditions and the relatively flat lower river slopes. Riprap design elevations may vary from the values suggested herein if additional site - specific data becomes available or as dictated by recent project experience in the area. The riprap protection should consist of an upper rock layer 2 feet thick, of which 45 to 65 percent of the rock is in the 500 to 1,000 pound range and 25 to 40 percent is in the 50 to 500 pound range. These recom- mendations correspond to suggestions provided by Ring County Shoreline Management and represent rocks large enough to resist the expected current and wave forces. A geotextile fabric should be placed directly on the compacted, smooth slope face to protect the fine grained soils from washing out through the riprap. We recommend that a nonwoven fabric, which meets the following mini- mum specifications, be used: Z w ✓ 0' co O W I J p_. w0 ga H w, _. Z� F- 0 Z uj • O O cn. 0 I- 11.1 w.. • cy O tii Z O . Z Boeing Military Airplane Company November 24, 1986 Page 15 AOS (U.S. Sieve No.) 70 Permeability, an /sec 0.1 Porosity, % 30 Grab Elongation, % (ASTM D -1682) 40 Grab Strength, lbs (ASTM D -1682) 180 Puncture Strength, lbs (ASTM D- 751 -68) 80 Burst Strength, psi (ASTM D- 751 -68) 290 Trapezoid Tear, lbs (ASTM D -117) 50 Dames & Moore A minimum 6 -inch thick sand bedding layer should be placed between the geotextile and the 2 -foot thick riprap layer for protection of the fabric. The bedding layer should consist of well - graded sand with a Unified Soil Classification of SW. The geotextile should be securely anchored at both the top and bottom of the slope. As an alternative to the geotextile filter described above, a graded soil and rock filter could be used. However, such a system would consist of a double -layer filter at least 1 foot thick. We believe that the geotextile system would prove to be more economical in view of the lower quantity of materials required and ease of construction. The toe apron of the riprap should extend horizontally at least 5 feet beyond the toe of the slope. This configuration will provide either a buried toe or a buttressed toe, depending on the existing ground inclination, to stabilize the revetment. The recommended riprap revet- ment design is shown on Plate 17. In keeping with King County's optimal stabilization design, a 3 -foot wide near - horizontal bench could be added just above the high water mark for river access. The bench should be covered with a 2- to 4 -inch thick gravel wearing surface and should be sloped toward the river to facilitate surface water drainage. Cut or fill slopes above the riprap should be revegetated with native grass, plants, and trees. Pea gravel can be added to the underwater riprap area to enhance sedimentation and revege- tation. Z H W. re d. JU O 0 W = N LL W 0' LL co Dr, H2. Z i- 0. ZF-' W ui U m' O - 0 1- = � U USD. O Z Boeing Military Airplane Company November 24, 1986 Page 16 oOo Dames & Moore We appreciate the opportunity to provide this study. Please contact us if you require further information or have any questions regarding the contents of this report. JBH:KSM:lac 00695-348-016 6 copies submitted Yours very truly, DAMES & MOORE By James B. Harakas, P.E. Associate And Kelly . JMerrill, P.E. Project Engineer I- ILI M- Z .. woo REFERENCES 1. California State Department of Transportation, "Nonwoven Geotextile Fabrics: Evaluation and Specifications for Subdrainage Filtration ", May, 1981. 2.. :Converse Consultants, "Report of Geotechnical Investigation, Proposed Boeing Employee Activity Center ", Converse Consultants Report No. 85- 5153 -01, dated July 23, 1985, for. BE &C Engineers. .3. Dames & Moore, "Report of Bank Stability Evaluation, Proposed Outfall, Boeing Employees Activity Center ", Dames & Moore Report No. 00695- 339 -005, dated March 11, 1986, for BE &C Engineers. 4. DeGraauw, A.F., et. al, "Granular Filters: Design Criteria ", ASCE Journal of Waterways, Coastal, and Port Engineering, February, 1984. 5. Jones, C.W., "Performance of Granular Soil Covers and Canal Linings ", ASCE Journal of Irrigation and Drainage Engineering, March, 1983. 6. State of Washington Department of Ecology, "Puget Sound Shore Erosion Protection Study ", 1978. 7. U.S. Army Engineers 8. U.S. Army 1984. Corps of Engineers, "Low Cost Shore Protection, A Guide for and Contractors ". Corps of Engineers, Shore Protection Manual, Vol. I and II, z 1a- Z' J0 0 WI 13 v� w w =, J N LL WO::. U a; = Z 0 Z U ;0 = W; : • 0 ▪ Z`. N1 • 715.77v* " Alb 9.42 ccl..to • I a C.42 • 3 9"; re 0 .1:34za C-771 (in ••• ,„ • 21,- CCret-—.7442 J44 i to•;-te** 9-1 01 -q1 I ,2..vozx 1 &.- . - =.1x Phase 11 211kat:NG I 11* 4144 ,_ \s____ 0 13-C2 113:F3,-t Phase 1 ta::•:CtaLenattreas4•..Cdt `Z:;40;;:a;, V V 1 11t)() It) VV 11'160 pf VV:' I 11)0 It) W:".)1t)11 Apin t*litiiI IlisIhiir VV 141100 I() VV It WO 1• 1- Z 2 __I 0 • 0 (J) U.1 LU W u_ al 0 g 5 u.< ZI- LUW 2D 0 O D- o i-- Li, uj 1— LL. 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M1!? jr' �Y; n., r?, vdi,{ r, xYT:; tw .."'o-"nh'.4'.rex;:�,pnsc�.Y',i ...: £�r..7 �cnr.`.`,• +..?.. .ly!?»:v...f,�•Y�wr•�•..g.Mw Yr,.rre .xyu y. t•h•.M1N3' Vr Nw Approxi msto Stations W27•50 to W28.50 Z Z 00 WI I_ V) w0 H 0 y O E- w W • 0 O w Z U= O ~ z ‘U111111) ;i111tt )I1 t 1(11) 111 I 111)(1 I1111: ,II 11111 ;I11,'• •. 11 111 + VV 1• 111 ,t • 1 t 1 1 qtr rrr MUM tam■ tom- MEM ■ _ NM= __ MOO Sfa• r INNS SIMS 1111•11111 r1 IN I IS 3TANI)AIil) 01( V1� 01/1 Is$ INS VI' M 4 10 20 1 Mee •• ••••••• t. AMK 40 (10 100 200 1 _1 ( -1 • 97A W ,10$,00^«' U'I' A W P)100 1 TA W 01100 ono " 100 - j 16 ► - 1 (d - ► 6.1 GRAIN SIZE IN MILLIMETERS ,,..... OILT o11 CLAY ...._.. �aor 3©t .Qe_......t..?R��....�fINC.I Ct RBtIf:M�RtUM:I�.'�IN�; 10 nrPT1- . USOS .�.. -..... C -A II1 Stir taco 111 .11111 y all L row fact, tt II ul `�Ilr�lnlii� t;11.tim 1 ina timid wll.h y(ilufi ti 1I,, • 0.01 Gradation Curve Phase 11 Area (West Bank) 0.001 Z ~ 2 W 00 CO U) W. W =' _1 F. W0 q .1 LL Q, • O 1— 0 Z I- 2 U N. . D 1—; W W! 1—ii...... • 0 W Z. Z PROTECTION METHOD - TYPE ADVANTAGES DISADVANTAGES No Action - allows time for cost /benefit analysis - no curtailment of erosion Relocation /Set -Back - no capital or operating cost for remedial action - no curtailment of erosion Slope Flattening - slope stable against deep- seated failure - subject to undermining of toe - minimum construction effort - no protection against wave actio - no surface stabilization - low construction cost - subject to wind, runoff erosion - slope vegetation - natural condition - subject to disease Revetments - stable, buttressed slope - subexcavation below the level fc - ease of construction protection - low maintenance - set -back required for slope trin - riprap (quarrystone) - flexible; good drainage - stacked burlap bags - semi -rigid - concrete block - semi -rigid - fabriform mats - possible aesthetic objections - concrete panels - rigid Bulkheads - ease of construction - vertical face maximizes wave rei - readily available materials - subsexcavation below tide level - low maintenance toe protection - stable slope - deterioration if not fully treat - soldier piles and timber lagging - steel sheet piling - most common bulkhead material - potential corrosion - timber crib walls - gravity structures, with some flexibility against settlement - high cost - concrete bin wall - anchors not required - susceptible to impact damage, v, - reinforced earth - gabions - no heavy equipment required - flexible Job No. 895 -348 >flc s:?ids'C:v ire,i4;' 'ifai:ia,C,k3 +21" zu ?V1 4441.13, •. " S"I(,N,avtown.. ctaS9F %:kR.`.$titi Y k 7S`.+ •n"X .. ii'i�agT.'ViYi1'S/f/?r.ziso f9dte..., . .r' • ."';ii ii:41::),fT4+'M. A't. ES /benefit analysis ing cost for deep- seated failure effort t lope .age aerials material with some ;t settlement - equired DISADVANTAGES aDMMENTS - no curtailment of erosion - no curtailment of erosion - subject to undermining of toe - no protection against wave action - subject to wind, runoff erosion - subject to disease - subexcavation below the level for toe protection - set -back required for slope trimming - possible aesthetic objections - rigid - vertical face maximizes wave reflection - subsexcavation below tide level for toe protection - deterioration if not fully treated - potential corrosion - high cost - susceptible to impact damage, vandalism - used only to provide time to evaluate alternatives - trade-off land for structure stability - requires slope grading to 2H:1V - requires graded filter or geotextile - should be concrete - filled otherwise subject to deterioration and vandalism - can be cantilevered or anchored - anchors suggested for H >10 feet - require weep holes for drainage - pressure- treated timber lagging - require weep holes for drainage Stabilization Alternatives River Bank Stabilization Study BOe1ng Developmental Center Dames & Moore ai;4. <+'tml y;,i, acs # «if7ashA Plate 16 A C 0 W 0 0 J a 0 co a0 cc 0 0 moo. 0 N w Min 0 0.l a0 0 m Y 0C 0 m 0 cc 0 0 03 Q • c Tt I0 N ® C 0 *' a o o� a r 0 0 0 N Typical Riprap Revetment Cross Section — Phase II Area River Bank Stabilization Study Boeing Developmental Center Seattle, Washington Dames & Moore al* PI . 6REANK 5Tir1 -Z Zr. , X6/1 (p11�5 ff/ 8/.6- FACILITIES ENGINEERING LIBRARY FILE COPY REPORT OF RIVER BANK STABILIZATION STUDY, PHASE I EMPLOYEES ACTIVITY CENTER SITE BOEING DEVELOPMENTAL CENTER SEATTLE, WASHINGTON FOR THE BOEING MILITARY AIRPLANE COMPANY 00695 - 348 -016 NOVEMBER 10, 1986 APR 1 0 1990 Dames& Moore RECFI" D JUN 2 41996 TUKVv PUBLIC WOE- z.: a •; _ H y W: 65; J Ui U O' co U;, W: W =. J W o+ u_ 4t. S Cy W. z� F- O z 2 Ds :U r ;o (.0;. iCF-1 W_., 'I Ws V! �— O Zi Dames & Moore Boeing Military Airplane Company P.O. Box 3707, M/S 46 -87 Seattle, Washington 98124 -2207 Ste. 500, Northgate Exec. Ctr. 155 N.E. 100th Street P.O. Box 75981 Seattle, WA 98125 -0981 (206) 523-0560 • November 10, 1986 Attention: Mr. L.F. Boulanger, P.E. Plant Engineering Manager, Facilities Gentlemen: Report of River Bank Stabilization Study, Phase I Employees Activity Center Site Boeing Developmental Center Seattle, Washington INTRODUCTION This report presents the results of our stabilization study of river bank areas adjacent to the Employees Activity Center which is currently under construction at the Boeing Developmental Center in Seattle, Washington. The scope of services for this study is outlined in our pro- posal dated April 28, 1986. Authorization was provided by your Work Order Request dated May 6, 1986. Our Phase I study covers about 800 lineal feet of river bank along the west shore of the Duwamish River. Our second study phase will encom- pass over 3,000 lineal feet of shoreline north of the Phase I area on both the west and east sides of the river. The areas for both phases of this evaluation are shown on the Vicinity Map, Plate 1, and Location Plan, Plate 2. Results of the Phase II study will be presented under separate cover. The river bank adjacent to the Employees Activity Center is undergoing continuing erosion by the Duwamish River. The erosion has Z Zi � w± JU, • . u) w: W =: w at LL ?' d. _' Z� 1— 0': .Z 2 Di • .43 ti • 1--- • Uco;.. • O ~' Z • r Dames & Moore Boeing Military Airplane Company November 10, 1986 Page 2 resulted in over - steepening of the river bank in several areas, thereby inducing unstable conditions, progressive slope failures and loss of ground. SCOPE The purpose of this study is to evaluate the extent and severity of the river bank erosion and provide recommendations for bank stabiliza- tion. To accomplish these objectives, our scope of services included: 1. Field reconnaissance of the river bank to identify the extent of the erosion and bank stability problem. An engineer from our staff observed and noted erosional areas, obtained represen- tative soil samples for laboratory testing, and photographed portions of the river bank for use during our office evaluations. 2. Laboratory tests on samples recovered from the field, including direct shear, gradation, and moisture- density tests. The direct shear and moisture- density tests were performed on samples reconstituted to near in -situ moisture and density conditions. 3. Cross sections of the river bank at about 50 -foot intervals. Surveys were performed by Hammond, Collier & Wade - Livingstone Associates, Inc., under subcontract to Dames & Moore. Cross section locations are shown on the Location Plan, Plate 2. 4. A brief literature search to gather relevant information con- cerning bank stabilization techniques. 5. Discussions with representatives of Ring County Shoreline Management, Washington State Department of Fisheries, and the U.S. Army Corps of Engineers to identify potential constraints associated with stabilization work in the area. 6. A report summarizing our findings and recommendations for appropriate stabilization techniques. Dames & Moore Boeing Military Airplane Company November 10, 1986 Page 3 SITE DESCRIPTION Z W. General: Field reconnaissance and laboratory testing of recovered 6 samples indicate that the surficial soils along the river bank in the U O UU, Phase I area are primarily sandy silt and sand. Heavy brush and black- Luz berry cover is often present in undisturbed areas along the river bank, O, although frequent bare areas were observed primarily in eroded or recently failed areas. Brief descriptions of site conditions and erosion features J u_Q U along the alignment are provided in the following paragraphs. Plotted --05 W cross sections of the river bank are included on Plates 3 through 5. Z Related photographs are presented on Plate 6. Z O 2 U C3 O� ca 11.1 u U' within about 0.5 feet of the surface often contain roots and organic W g 'U =; matter. The soils appear to be in a loose to medium dense and medium 0E-. stiff condition, with near - surface soils in eroded areas expected to be in a looser state. The fine grained nature of these sediments and low to moderate densities renders them very susceptible to erosion from wind and water forces if left unprotected. Soil Conditions: The soils along the river bank in the Phase I area consist mainly of fine to medium sand with a variable silt content and sandy silt. The gradation curves shown on Plate 7 are representative of the gradation range of the river bank soils in the study area. Soils Results of the direct shear tests are shown on Plate 8. The tests were completed for both the fine to medium sand and sandy silt soils to develop a representative range of strength for the river bank soils. River Characteristics: The Duwamish River is a relatively large, slow - moving river in the study area. It is about 250 feet wide, with a probable maximum depth near the site of 15 to 20 feet during peak river flow. The depth variation in the Duwamish River near the site is influenced by both tidal effects and river flow conditions. River flow is known to vary widely in the area, from about 200 cubic feet per second (cfs) to 12,000 cfs. Tidal effects will have little influence on river 'vit�%'. • •. Dames & Moore Boeing Military Airplane Company November 10, 1986 Page 4 depths during periods of high river flow and a large influence during periods of low river flow. The maximum high water mark is expected to be around Elevation +7 (Mean Sea Level datum). The low water mark could conceivably reach near Elevation -8, although this condition could occur only during infrequent periods of low river flow and extreme low tides. Information provided by the Army Corps of Engineers indicates that average current velocities are about 5 feet per second. River Bank Conditions: Most areas from Station W 1 +00 to W 10 +00 exhibit some degree of erosion. From Station W 1 +00 to about W 4 +25, the bank above Elevation +2 to +5 slopes upward at inclinations as steep as 1/2 to 1 (horizontal to vertical) (see Plate 6, Stations W 3 +00 to W 4 +00). Underwater slopes are much flatter at near 2 to 1. The top of the bank in this area is near Elevation +14 to +16. A distinct slump feature was observed between Stations W 4 +25 and W 4 +75, with a near vertical slope inclination above Elevation +3 (see Plate 6, Stations W 4 +00 to W 5 +00). A section of river bank stabilized in conjunction with construction of the Employee Activity Center exists between Stations W 5 +15 and W 5 +72 (see Plate 6). This section previously contained near vertical bank slopes which were cut back to 2 to 1 and covered with rock riprap for protection of a storm drain outfall. The recommendations for stabiliza- tion of this area are contained in our report to BE &C Engineers, Inc. dated March 11, 1986. Our visual observation of this area indicates that our recommendations for construction of the riprap layer were, in general, not properly implemented. It does not appear that the upper riprap layer was properly graded or of sufficient thickness. North of the outfall location, the river bank areas above Elevation +2 are typically at about 0.75 to 1, steepening to about 0.25 to 1 near Station W 7 +00 (see Plate 6, Stations W 7 +00 to W 8 +00). Similarly steep upper bank sections exist to the north end of the Phase I area at about Station W 10 +00, although slopes tend to flatten signifi- cantly north of about Station W 9 +00. Underwater slopes along this sec- tion are 2 to 1 or flatter. Z W. JU 00 NO, WI JF.. W LL WO Q' =• d I--W Z �. F- 0 Z 2 uj O N o E- W W' H • U. LL 0 w Z'. U =: O~ z ':... Boeing Military Airplane Company November 10, 1986 Page 5 EROSION ASSESSMENT Dames & Moore It is obvious from our field reconnaissance and from review of the survey data that several bank sections in the Phase I area have undergone significant erosion and will continue to do so unless stabilization measures are implemented. Other bank areas are apparently more stable, but may be affected by erosion that is occurring at a slow rate. Sections of particularly severe erosion include the following: Section Lineal Feet Station W 2 +00 - W 2 +75 75 Station W 4 +00 - W 5 +15 115 Station W 5 +72 - W 9 +00 328 TOTAL 518 REVIEW OF STABILIZATION ALTERNATIVES We have conducted a brief literature survey and reviewed past Dames & Moore stabilization projects to assemble a list of applicable protec- tion techniques that may be considered for the Phase I area. A list of references is included immediately following the text of this report. The alternatives identified are discussed below and are summarized on Plate 9. The options can be broadly grouped into five areas, as follows: 1. No action. 2. Relocation or set -back of planned facilities. 3. Slope flattening. 4. Revetments. 5. Bulkheads. No Action: This is not a feasible long -term solution in the Phase I area as erosion will probably continue in several areas and could even- tually affect the Employees Activity Center Building and jogging path. This option may be appropriate in relatively stable river bank areas, but is not recommended where recent and active slope erosion exists. Z w. 6D' J U: 0 N 0 ; ' tow w =; • J CO u. .w O wQ LL U D. =a �w Z �. Z O0, w w: U0 �. .w • - • • tUZ` U ..O •.' Z • Boeing Military Airplane Company November 10, 1986 Page 6 Dames & Moore Relocation or Set -Back of Existing and Planned Facilities: This option would involve a loss of land by erosion for protection of the structure. The amount of land required as a buffer zone would depend on the planned design life of the structure and projected erosion rates. It is our opinion this option is not viable. Slope Flattening: Reduction of river bank slope inclinations would require minimal construction efforts while providing higher factors of safety with respect to deep- seated or sloughing failures. Revegetation of the bank slopes would add some protection against continued erosion, although it is unlikely that such protection could be established quickly and thoroughly enough to completely halt erosion. It is more likely that flattened revegetated slopes would merely slow the rate of erosion. This alternative might be appropriate where erosion rates are slow, but is not recommended in active erosion areas or where river bank slopes have recently failed. Z • = '-' W • Wes. JO U Oo N co W • . J ww O: LLQ 21 a �w Z t- O. Z I- uf :0 I-, S U'; O 111 Z: .w N Revetments: Revetments, or slope facings, would generally require 1-• flattening of the slopes to an inclination on the order of 2 to 1 for. Z construction practicality and improvement of overall slope stability. Appropriate slope inclinations can be established by cutting or filling. We anticipate, however, that filling will meet significantly more resistance by the regulatory agencies than cutting. Revetments historically have been constructed of such diverse materials as old tires, burlap bags, riprap, and concrete rubble. Revetments made of these materials are flexible and able to adjust to some deflection or distortion without failing. More rigid revetments may consist of Fabriform mats (proprietary), concrete panels, or intercon- nected concrete blocks such -as Armorflex (proprietary). Revetments require a filter layer to allow drainage and reduce hydrostatic pressure build -up, yet prevent fine soil particles from escaping. Filters can be graded soil and rock or may incorporate a geotextile. Revetments are ..,, ..*^, - '.- •��•• �. >.':>...'� . , �, , Dames & Moore Boeing Military Airplane Company November 10, 1986 Page 7 typically low maintenance installations, and can be made more aestheti- cally and environmentally acceptable by establishing local vegetation on the sloping face. We believe a riprap revetment represents one of the better alternatives for mitigating river bank erosion in the project area. Bulkheads: Bulkheads are typically used in relatively severe situations where wave heights are high, damage potential is large, or land is not available for inclined slopes. Typical bulkhead installations include soldier piles and timber lagging, steel sheet piles, concrete bin walls, reinforced earth walls, and gabions. Bulkheads are generally more expensive to construct than other types of bank protection. Since bulkheads typically have vertical faces for construction ease, wave reflections are maximized, thereby increasing the potential for over- topping and scour in front of the structure. PROJECT CONSTRAINTS In order to obtain updated information regarding constraints placed on shoreline stabilization projects, we contacted representatives of three agencies including Ring County Shoreline Management, Washington Department of Fisheries, and the U.S. Army Corps of Engineers. Pertinent considerations for stabilization of river bank areas pro- vided by Ring County Shoreline Management include: 1. Aesthetics: Restoring the stabilized slopes to near - natural conditions with vegetation. 2. Access: The stabilizing method should allow easy access to the river for fishing and recreation. The Ring County representative with whom we spoke described a recent pilot project for Seattle City Light on the Duwamish River that the County encourages other projects to emulate. That project included Z • Z w u6= U - 0 co 0 w= J CO w 0 u- Q; N 0 F=.w. _. Z I- 0 ZH 2 U � O N` I- r- u" 0 Z; 11/ uy 0 I O •- Boeing Military Airplane Company November 10, 1986 Page 8 Dames & Moore graded riprap without a geotextile. A 3 -foot wide horizontal bench was included in the slope just above the maximum high water mark to allow river access. Riprap areas below the maximum high water mark were infilled with pea gravel. The pea gravel is intended to trap fine river sediments and thus allow salt grass or other local vegetation to become established. Soil was placed above the maximum high water mark for establishment of alders and other local vegetation. The Washington Department of Fisheries provided the following cri- teria for design and construction of revetments or bulkheads: 1. For sloping revetments flatter than 1.5 to 1, the revetment must intersect the beach at or shoreward of Elevation 0.0. 2. For sloping revetments or bulkheads steeper than 1.5 to 1, the revetment /bulkhead must intersect the beach at or shoreward of Elevation +2.4. They also stated that construction cannot be scheduled during the period of April 1 to June 15, due to the seasonal juvenile salmon migration. A state hydraulic project permit will also be required for any proposal work, whether new construction or maintenance. The Corps of Engineers indicated that small stabilization projects can fit under their nationwide permit program already in place if the following criteria are met: 1. 500 feet of bank or less protected, and 2. Placed fill totals less than 1 cubic yard per running foot waterward of mean higher high water. Additionally, bank erosion or loss that has occurred within the past year can be repaired or replaced under the nationwide permit. Projects that do not fit into the above categories will require individual permits. z r4 2 6 JU UO: N0, W =, N O W LL Q; -a W I- • Z t- O, Z w W,. U ww - 0 Z. W Up U =. 0 1- z VI Boeing Military Airplane Company November 10, 1986 Page 9 Dames & Moore aft The Corps has no engineering requirements for this type of project unless nearby federal projects are impacted. RECOMMENDATIONS Based on our review of site conditions, we recommend that the following sections of bank in the Phase I area be stabilized: Stations W 2 +00 to W 2 +75, W 4 +00 to W 5 +15, and W 5 +72 to W 9 +00. The remaining river bank areas are presently stable and do not represent a high risk of erosion, slumping, or failures. Stabilization efforts in these areas may not be necessary or may be deferred due to the apparent low erosion rates. We recommend, however, that the river bank areas adjacent to the Employees Activity Center be monitored periodically as a basis for evaluating the effectiveness of rehabilitated areas and to identify other portions of the bank that may require stabilization in the future. In view of the constraints outlined by the agencies contacted during this study, we recommend that the river bank sections that require rehabi- litation be stabilized with a sloping revetment. Sloping revetments appear to be more in keeping with the environmental and aesthestic guide- lines provided by the various agencies, including river access and restoration of a natural appearance to the repaired areas. In addition, properly designed and constructed revetments can provide the long -term protection needed with little or no maintenance for the currents and light wave action present in the Duwamish River. We further recommend that flexible revetments consisting of rock riprap or similar materials be used for this project. Such riprap revetments are common in the Puget Sound area, contractors are familiar with the construction procedures, and necessary materials are available locally. Although we have not completed an economic evaluation to assess the relative cost of various revetment types, we believe that a rock riprap revetment will prove to be the most appropriate alternative. The existing river bank slopes that require stabilization should first be cut back (or filled) to an inclination of 2 to 1 to enhance .Z Hw r4 2. • JU U O' n0; CO w w =; J - w O' Na.. I-w 1- O. • .z I- w cri :0 w F., — • — Z. AJJ U N: O ~' Z - Boeing Military Airplane Company November 10, 1986 Page 10 ►: Dames & Moore overall stability. If cutting is not possible, the recommended slope inclination can be established by filling or a combination of cutting and filling, provided approval can be obtained from the permitting agencies. Slopes should be cleared of all vegetation before filling. Fill should consist of clean imported sand and gravel with less than 5 percent passing the No. 200 sieve. Cut slopes so constructed should be cleared of all loose soil and debris, and compacted using light compaction equip- ment. Compaction of fill should be accomplished in this manner, also. The design and construction of the slopes should be in accordance with the Department of Fisheries criteria outlined previously. An existing jogging trail at the top of the bank is within 10 to 12 feet of the bank at some locations and may need to be relocated. Slope cuts should be graded gradually into the natural banks surrounding the protected areas to prevent flank erosion. The riprap should extend throughout the zone of significant tidal influence, from at least 1 foot above the high water mark to a reasonable low river level. Accordingly, we recommend that the riprap extend from at least Elevation +8 to at least Elevation -2. Riprap extending to the extreme low river level of about Elevation -8 would be prohibitively expensive and unnecessary due to the infrequent very low water conditions and the relatively flat lower river slopes. Riprap design elevations may vary from the values suggested herein if additional site - specific data becomes available or as dictated by recent project experience in the area. The riprap protection should consist of an upper rock layer 2 feet thick, of which 45 to 65 percent of the rock is in the 500 to 1,000 pound range and 25 to 40 percent is in the 50 to 500 pound range. These recom- mendations correspond to suggestions provided by Ring County Shoreline Management and represent rocks large enough to resist the expected current and wave forces. A geotextile fabric should be placed directly on the compacted slope face to protect the fine grained soils from washing out through the riprap. Z F— W: ev 6U U O'• UU, W ='. J 1— w O. � J u. • U = d w. _; Z F.. O Z 2 D. • '0 �. `w w; _ O. Cu co: P▪ _' O~ z Boeing Military Airplane Company 1986 Page 11 Dames & Moore We recommend that a nonwoven fabric, which meets the following mini- mum specifications, be used: AOS (U.S. Sieve No.) 70 Permeability, cm /sec 0.1 Porosity, % 30 Grab Elongation, % (ASTM 0 -1682) 40 Grab Strength, lbs (ASTM 0 -1682) 180 Puncture Strength, lbs (ASTM D- 751 -68) 80 Burst Strength, psi (ASTM D- 751 -68) 290 Trapezoid Tear, lbs (ASTM D -117) 50 A 6 -inch thick sand bedding layer should be placed between the geotextile and the 2 -foot thick riprap layer for protection of the fabric. The bedding layer should consist of well - graded sand with a Unified Soil Classification of SW. The geotextile should be securely anchored at both the top and bottom of the elope. As an alternative to the geotextile filter described above, a graded Boil and rock filter could be used. However, such a system would consist of a double -layer filter at least 1 foot thick. We believe that the geotextile system would prove to be more economical in view of the lower quantity of materials required and ease of construction. The toe apron of the riprap should extend horizontally at least 5 feet beyond the toe of the slope. This configuration will provide either a buried toe or a buttressed toe, depending on the existing ground incli- nation, to stabilize the revetment. design is shown on Plate 10. The recommended riprap revetment In keeping with Ring County's optimal stabilization design, a 3 -foot horizontal bench could be added just above the high water mark for river access. The bench should be covered with a 2- to 4 -inch thick gravel wearing surface. Cut slopes above the riprap should be revegetated with Z Z 1- F-w re 2 6 J U. U O' WI LL Waa O: LLQ W. H O: • Z W O N' wuf Z` ui 'I'; O z Boeing Military Airplane Company November 10, 1986 Page 12 Dames & Moore local plants and trees. Additional pea gravel can be added to the under- water riprap area as an aid to sedimentation and revegetation. We appreciate the opportunity to provide this study. Please contact us if you require further information or have any questions regarding the contents of this report. ..ms's 11 dr• 5 e • H'q,Q °•• • • • i • • i i tP) • • • •j• ,e'.•• 17h�s'�LO• i '4 O 4* ....•.. JBH:KSM:lac 00695 - 348 -016 6 copies submitted '"& Yours very truly, DAMES & MOORE es B. Harakas, P.E. Associate And Kelly S. Merrill, P.E. Project Engineer z . 1I- �w . .0 O': Nc Co w U1= w O: g LL < I- 0' Z w w. 2 W`; 0,. Zi Li! U ;0.�'', REFERENCES 1. California State Department of Transportation, •Nonwoven Geotextile Fabrics: Evaluation and Specifications for Subdrainage Filtration ", May, 1981. 2. Dames & Moore, "Report of Bank Stability Evaluation, Proposed Outfall, Boeing Employees Activity Center', Dames & Moore Report No. 00695- 339 -005, dated March 11, 1986, for BE &C Engineers. 3. DeGraauw, A.F., et. al, •Granular Filters: Design Criteria ", ASCE Journal of Waterways, Coastal, and Port Engineering, February, 1984. 4. Jones, C.W., "Performance of Granular Soil Covers and Canal Linings ", ASCE Journal of Irrigation and Drainage Engineering, March, 1983. 5. State of Washington Department of Ecology, "Puget Sound Shore Erosion Protection Study ", 1978. 6. U.S. Army Engineers 7. U.S. Army 1984. Corps of Engineers, "Low Cost Shore Protection, A Guide for and Contractors ". Corps of Engineers, Shore Protection Manual, Vol. I and II, 8. , "Report of Geotechnical Investigation, Proposed Boeing Employee Activity Center ", Converse Consultants Report No. 85- 5153 -01, dated July 23, 1985, for BE &C Engineers. : z _ 1— • o: ' 6 _i 0. 0O' ' `N W �_ H. w 0 N = C3: H z 0 0 H: ,w w` wz:. U� 0 ~' 9-99 C, 9.43 9 -49 `1 9.48 9.59 9.44 } 9-75 9.70y0 0-9 -46 9-6/1. 9 -42 ! _ 9.66 E 9 -35 9.67 9-62- 1 9 -120 OUWAMISH WATERWAY 9-101 9-80 '� 9.101 x105 pi 9-85 ANNEX i —____5 i 9.102\ 9.56 —r 1-140 9-130 &TRH • :, Phase II 9.401 OXBOW PARKING LOT CENTER 13 -05 Phase 1 S. NORFOLK No Scale Vicinity Map River Bank Stabilization Study Boeing Developmental Center Seattle, n Washin to 9 RAAoois FAXAPAXXXXII LiamJ 1.1 1.1 1—J L—J L—I 1_1 L L. i L:4 Approximate Stations 3+00 to 4+00 West Approximate Station 5+50 West Approximate Stations 4+00 to 5+00 West 1: • ' , 7 F---\ -■, - . Approximate Stations 7+00 to 8+00 West Phase I Area - River Bank Stabilization Study. Boeing Developmental Center - Seattle, Washington "7,14rit'Vtl.,17,M14'7.retrn. PERCENT FINER BY WEIGHT 100 90 80 70 60 50 40 30 20 10 U.S. STANDARD SIEVE SIZE 3 IN 1.5 N 3/4 IN 4 1 4 IMO I1 Station +50 + . , 1 i 0 1000 1 1 1 1 Static) 1' 1 4 n 5+ • 0 0 100 10 1.0 0.1 GRAIN SIZE IN MILLIMETERS 0.01 0.001 Gradation Curve Phase I Area River Bank Stabilization Study Boeing Developmental Center ' :.:«! z W. 00 N 0. W 2' W ID 0, ga 4/)a 11.1 . zl.. zo ui D o. o o 0 ww I- �. Z. W I— 0'' z Station Depth Soil Type Moisture Content toefnt Dry Weight Dry Density LbsJCU.Ft. Normal Pressure Lbs q.Ft.LbsJSq.Ft.LbsJSq.Ft. Peak Strength Ultimate Stren 4 +50 Surface Sandy silt 32.6 83 500 600 ___ Surface Sandy silt 1500 1150 ___ 5 +00 Surface Fine to medium sand 17.5 86 500 430 ___ Surface Fine to medium sand 1500 1070 1030 Note: Moisture content and density measured on remolded samples. Direct Shear Test Data Phase I Area River Bank Stabilization Study Boeing Developmental Center Dames i Moon Z Q 11—' fY 00 A CO C NW W I: J l— o; 4 z y. U D'. ; 0 — 0E-1 Ul ty O: Z' Z i . , PROTECTION METHOD - TYPE No Action Relocation /Set -Back Slope Flattening - no surface stabilization - slope vegetation Revetments - riprap (quarrystone) - stacked burlap bags - concrete block - fabriform mats - concrete panels Bulkheads - soldier piles and timber lagging - steel sheet piling - timber crib walls - concrete bin wall - reinforced earth - gabions ADVANTAGES - allows time for cost /benefit analysis - no capital or operating cost for remedial action - slope stable against deep- seated failure - minimum construction effort - low construction cost - natural condition - stable, buttressed slope - ease of construction - low maintenance - flexible; good drainage - semi -rigid - semi -rigid - ease of construction - readily available materials - low maintenance - stable slope - most common bulkhead material - gravity structures, with some flexibility against settlement - anchors not required - no heavy equipment required - flexible DISADVANTAGE - no curtailment of eroE - no curtailment of erosi - subject to undermining - no protection against IA - subject to wind, runoff - subject to disease - subexcavation below the protection - set -back required for - possible aesthetic obje - rigid - vertical face maximize: - subsexcavation below ti toe protection - deterioration if not fl - potential corrosion - high cost - susceptible to impact c Job No. 695 -348 :il'c.::ii.e. °r��;�i:4�: �.r.:• sit,. ikfiu�k` eiri��a` ti+ zC�dr "`1;�!';{�:�',.eaH�:�ir %ts;d:� a ate? 4.11 }ti iforta :kA7i:Y S; # 5 benefit analysis ng cost for deep- seated failure effort ge :erials material gith some settlement aquired: l DISADVANTAGES COMMENTS - no curtailment of erosion - no curtailment of erosion - subject to undermining of toe - no protection against wave action - subject to wind, runoff erosion - subject to disease - subexcavation below the level for toe protection - set -back required for slope trimming - possible aesthetic objections - rigid - vertical face maximizes wave reflection - subsexcavation below tide level for toe protection - deterioration if not fully treated - potential corrosion - high cost - susceptible to impact damage, vandalism - used only to provide time to evaluate alternatives - trade -off land for structure stability - requires slope grading to 2H:1V - requires graded filter or geotextile - should be concrete- filled otherwise subject to deterioration and vandalism - can be cantilevered or anchored - anc'')rs suggested for H >10 feet - require weep holes for drainage - pressure - treated timber lagging - require weep holes for drainage Stabilization Alternatives River Bank Stabilization Study Boeing Developmental Center Dames & Moore .•'. Plate 9 1 r O mC a0 W° 'in 02 oO #• , WOO. - x O C Q 0 0 m Ze 0 GS >> (0 0 C Nt I N 0 c 0 0 = )1. 413O 0 2 4 a0 cc oa cc N 0.5' Sand Bedding Layer Geotextile Fabric Ground Surface ae C re X W N 0 0 a 0 _c to o° • x0 • «c za «0 a 0aTo 0'. O °v O 0 0 00 • z 0 0 V Typical Riprap Revetment Cross Section - Phase I Area River Bank Stabilization Study Boeing Developmental Center Seattle, Washington Dames & Moore z Z • mow` JU oo .(n W; W LL .2 File: L 9b -00'� Srnm Drawing# rte. Itecb Ad, 'aliJfwicv ' • • • f 23 +02.79 BASELINE PK NAK. WITH CONTROL FLASHER C83 • OXBOW BRIDGE S 102ND ST N8811'51'W 7 \\ 7 % % L KEY PLAN SCALE: NO SCALE APPROVED DATE SIN REVISION BY 13 +37.71 BASELINE CONTROL L FUME BOE/A/G FACILITIES DEPARTMENT O D 8'441is hR/ /FR I I C82 1 \ \ \ \ \ _ \ / I / 1. / 9 +07.99 BASELINE HUB & TACK \ \\ CONTROL CAP 2 +00.00 BASEUNE PK NNL WITH CONTROL FLASHER- -4 . 0+00 BASEUNE HUB & TACK C81 C8o J ACCEPTABILITY NS DESIGN AND /OR SPECIFICATION IS APPROVED APPROVED BY DEPT. DATE Vitae W7 WRY KEY PLAN EED CITY R OF CEIV TUKWIU` JUN 171996 PERIMR CENTER RECEIVED JUN 171996 TUKWILA PUBLIC WORKS DUWAMISH WEST RIVER BANK STABILIZATION CML MASTER YARD OXBOW Drro N0. 11117111 111 111 f f III III III III 111 Ilf TII III 111 11f Ili ill 'Ill Ill Il' Il'I III 1 1 1 li- 2 I .. 3 I l--...A''{ I I5 1 1 I5 "- OIf: CiIZ..8IZ \. 6IZ; • gly..'i�y LIT HIT 1111 uRluu uuhm ullhul ullluliluulml uuluR uuluu mduu uufiul uuhul iiuilmluuluu uuluu uulml mdul 5+79.63 BASELINE REBAR M1111 RED CONTROL CAP 3+53.25 INN 3+31.5 X 12.9 'TOP OF BANK c I13.1 "N' � ry N CBO C511 PriPitArt# C80 C5003•' 13.2 ri.D it 4;;7: I it 24 CORONWOOa 24 S.fO OFIW B K IVA Oft x134 9T 4.24 leN 12,7 PLAN - AREA 2 N SCALE: 1 " =20' 2482.5 82.5 16^ WILLOW 12^ GATED 12^ STEEL PIPE I.E. - 4.87 12.8 / lREDE 12.6 \2+OO BASELN P,K NAIL W CONTROL FLASH 12.4 80 13 5 1 +52 0500 12^ 13.8 WILLOW 13.1 12^ WILLOW UMIT of GRADING 13.5 5.10 OHW 4.24 MIRY 14.3 PLAN -AREA1 SCALE: 1 " =20' 0 +00 BASELINE HUB & TACK DATE REVISION 1 13.8 12.5 PATH 14 UMR GRAN 13.4lll//� 0500 et iiR•i.�ii/ C 1 / "ker. i s Z II���, ''h . s�iA►��i� I � ♦ rii i! �•���•:44� c, C514 • IIIw i�,,,k or, 111 Miry; -Y.♦.4 II , - ���llllll . t 1.40• IIIIIr1�/m1Ilfr *WI .0 77.16 �� 41;� :f I' 44 N m�iill/ 5 APPROVED Vo DATE -8.0 -7.7 X X -7.8 /M h co -8,0 -8.2 -8.7 X /bb 1 I I X -10.4 I m I m -9.4 X -8.4 >I -9.0 -7.9 x x -8.1 -9.0 X -10.5 x -10.4 • x -10,7 X -1D.3' X -11.1 X -10.9 X -11,2 (X -12.1 N X -11.4 X -12,2 X -12,4 BOEEiW FACILITIES DEPARTMENT X -16.9 wfl'f+t _ LE%%PE8 tti6 -13.0 x -13.3 ACCEPTABILITY TNIS DESIGN AND OR SPECIFICATION IS AP ROVED - APPROVED BY DEPT. DATE .:- 'YUDEZ APPROVED LEGEND: ARMOR ROCKS VEGETATED GEOGR1D CONSTRUCTION GENERAL NOTES: 1. 10D YR FLOOD - EL. +8.3 CONSTRUCTION NOTES: L FOR VEGETATED GEOGRID CONSTRUCTION DETAILS SEE SHEET IS500 QFOR SEEDED AREAS DETAILS 2 SEE SHEET 1.5500 3 AREA 1 - REMOVE 14' DIAMETER WILLOW TREE THAT HAS BEEN UNDERMINED AND WS EXPOSED ROOTS. AVOID DAMAGING TRAIL /SERVICE ROAD. RECEIVED CITY OF TUKWILA JUN 1 1 1996 PERMIT CENTER RECEIVED JUN 17 1996 TUKWILA PUBLIC WORKS CONTOUR INTERVAL = 1' DATUM: USGS MSL = 0.00 CITY OF TUKWILA DATUM NAVD = MSL + 3.6' 20' 10' 0 10' 20' 40' SCALE: 1 " =20' PLANS - AREAS 1 & 2 LAST REVISION 96024C.L \624C080S ri FACIUTY o DESIGN SUPPORT . TR" DUWAMISH WEST RIVER BANK STABILIZATION CML YARD OXBOW SHEET C80 J06 N0. 96024 DWO N0. DF COMP N0. I I1111111 11111 1 111.111 III1111 II11111 111111 Il111�1 1� I1111111111111 Il1I'11111' 11 1 11 { - .11`'•I' I 1 3I:.. . L. _11.1411. ,• ..5I 6I 1.�.r.. OI1: DI7, 9I:S� LIZ or 9I7. '1 'jZ HIS _.7•IZ..Ilz• -QI1' (j1L 9I1 LIE OID 1111 IIIIIIIII IIIIl111111111111111171111IIIIIIIIII IIIIIIIII IIIIlu111u11111111u61u IIIllllll IIIllllll IIIIIIIII II IIl1111111111111 IIIIIII� LEGEND: VEGETATED CEOGRID • CONSTRUCTION x -11.3 GENERAL NOTES: 1. 100 YR FLOOD - EL +6.3 x -9.4 X -11.7 9 +07.99 BASELINE SET HUB & TACK x -11.6 13.6 ASPH LT 13.3 13.7 ` PATH 13.6 12' BILLOW • 12.2 X -11.6 X -10.1 TOP OF BANK TOP OF BANK 13.3 X -11.1 Lam■ C8 10514 x -9.9 X -10.1 x -10,0' x -10.7 5 +79.63 BASELINE REBAR B1TH RED CONTROL CAP x -10.7 CONSTRUCTION NOTES: 13.2 13.1 -10.1 x -10.1 QFOR VEGETATED GEOGRID CONSTRUCTION DETAILS SEE SHEET LS500 FOR SEEDED AREAS DETAILS 2 SEE SHEET L5500 2+00.00 BASELINE PK NAIL YlTH CONTROL RASHER PLAN - AREA 3 SCALE: 1 " =20' RECEIVED CITY_ 1f TUT LA JUN -1 71996 PERMIT CENTER PERMIT CENTER RECEIVED 'JUN 17 1996 TUKWILA PUBLIC WORKS CONTOUR INTERVAL = 1' DATUM: USGS MSL = 0.00 CITY OF. TUKWILA DATUM NAVD = MSL + 3.6 FT FACILITIES DEPARTMENT ACCEPTABILITY THIS DESIGN AND OR I, SPECIRCA710N 1 M D • APPROVED BY DEPT. DATE UDEZ APPROVED SUBTITLE . PLAN - AREA 3 20' 10' 0 10' 20' 40' SCALE: 1 " =20' Irgif tith‘ FACILITY DESIGN SUPPORT LAST REVISION TRH DUWAMISH WEST RIVER BANK STABILIZATION CML . YARD OXBOW 701r11D. DCA -96024 _ It III 111 ICI �I 111 111 111 III III 111 III III 111 111 • 111 011 11T 1111.11.Ij1� I I 1 Ir-.�. 12 .I 13 I x..14 _" 1..5 1 16 rr. ,1• (31 _ell! Liz; UB E17. TIT :..eIZ.. -.E0- •,.Ilz�_Q�t Jjt ell LI 9lt uu uuluu uulml Ijuhul uu1uuluuhul ulduu uuluu Illduu uufuu ull6ul im1111 uulml uuluu uuluu uuluZ LEGEND: ARMOR ROCKS x -10.6 VEGETATED GEOGRID CONSTRUCTION x -10.4 x -10.2 x -10.3 GENERAL NOTES: 1. 100 YR FLOOD - EL +8.30 -8.8X . x -10.3 x -11.8 X -9.6 X -11.9 TOP OF BANK NEW TOP OF BANK TOP OF BANK 9.9 X -11.7 X -11.4 X -11.5 x -11.4 ?` 10 +ei.eo 13 +37.71 BASELINE PK NM. VA114 CONTROL FLASHER 10+67. t0 +36.60 4.24 MHW 5.10 OHW TOP OF BANK x -8.7 9 +07.99 BASELINE • HUB 8 TACK CONSTRUCTION NOTES: .19 +71. ,,p G PATH 10.4 TOP OF BANK 75 Q FOR VEGETATED GEOGRID CONSTRUCTION DETNL SEE SHEET 1.5500 2 QFOR SEEDED AREAS DUALS SEE SHEET LS500 3 FOR PATH RELOCATION DETAILS SEE SHEET L560 L INSTALL CAP ON PIPE EXTENSION L AREA 5 - EXTEND EXISTING 18' DIAMETER CONCRETE PIPE AS REQUIRED. MATCH EXISTING PIPE. INSTALL EXISTING FLOW RESTRICTING SEGMENT ON END OF NEW PIPE. 1 9 +07.99 BASELINE HUB & TACK 5 +79.63 BASELINE REBAR 91111 RED CONTROL CAP JUN 1 71996 PERMIT CENTER ACCEPTABILITY THIS DESIGN AND /0R SPECIFICATION 15 APPR ID APPROVED BY TriVUDEZ SUM( RECEI\f JUN 17 1996 TUKWIL,. PUBLIC WORK: CONTOUR INTERVAL = 1' DATUM: USGS MSL = 0.00 CITY OF TUKWILA DATUM NAVD = MSL + 3.6 FT 20' 10' 0 10' 20' 40' SCALE: 1 " =20' Ctio PA3K1Cl?Ia.7�7 kil�1µ1idag,v warm PLANS - AREA 4 & 5 FACILITY DESIGN SUPPORT SYMBOL 04TE IAST RENSION DUWAMISH WEST RIVER BANK STABILIZATION YARD OXBOW 40B N0. DCA -96024 DWO NO. COMP N0. IIIIIIIIIIIIIIIIII} I1rIIII! IIIIIIIIIIIIIIIIIIIIIIIIIIIII�I111111111Ii1III 1I11,IIIIIIIII11 LIUI1: OIZ. _SE 6IZ;_9I7.- EC l'jE ...EI7....SIz_ ..IIE._Q 91 LIT BI1 uu mduu uuluu uuluu uuhm uuhm uullm mduu uuhm I uulm1151 uu uul111111 ulull uul 111 m I ti LEGEND: X -11,0 VEGETATED GEOGRID CONSTRUCRON x -10.7 •'X -10.9 x -10.8 x -11.7 GENERAL NOTES: X -12.0 1. 100 YR FLOOD • EL. +6.3 -9.8 x -11.1 • P/� x -11.8 X -11.9 X -12.0 X -14.1 X -13.8 -3.5 -11.0 -14.1 -14. X -14.1 X -14.0 6" DECIDUOUS TOP OF BANK X -14.2 X -14.2 x -14.9 % -15.1 23 +02.79 BASELINE • PK NAIL WITH CONTROL FLASHER x -13.8 X -13.8 22 +77.1 x -13.8 -4.5 X x -13.3 22 +57.30 13 +37.71 BASELINE PK NAIL %MTH CONTROL FLASHER - 3.7 -4,4 X -3.2 '\ -2.8 -3,7 y -3.D % x -12.7 _11\ X10. V( -9.3 PLAN - AREA 7 SCALE: 1 " =20' TOP OF BANK 9. 11.4 23 +02.79 BASELINE PK NAIL WITH tt CONTROL FLASHER ,T • F ASPHALT MSL 4.24 MHW 5.10 OHW TOP OF BANK 13+67. 13 +37.71 BASELINE PK NNL 00TH CONTROL FLASHER 9 +07.99 BASELINE HUB & TACK CONSTRUCTION NOTES: AFOR VEGETATED GEOGRID CONSTRUCTION DETAIL SEE SHEET L5500 AFOR SEEDED AREAS DETAILS SEE SHEET 15500 A FOR PATH RELOCATION DETAILS SEE SHEET 1580 PLAN - AREA 6 SCALE: 1 " =20' RECEI ""'-' JUN 17 1996 TUKw, PUBLIC WUHh, ACCEPTABILITY 'HIS DESIGN AND/OR SPECIF1CATION IS APPROVED APPROVED BY DEPT. DATE ..'•'UDEZ) 11111111 111111 I�IIIII ,111111 IIIIIII,I1111111 IIIIIhIl11111f 111111j11�11111 IIf 1111I1�111111+ I. 1 {,.I 2I 3Ir. 4I >" I o5l G y7. . ' I OI1: 917 8IZ". LV�Z;_97.' 9IZ. 117. - EIE �7.IZ:•..IIZ _DID 9)0 8IT LIT IT 1111 111111111 uulilu 111111111 IIIIIIIIIIIIIIIIIII u111uu1111dm1 IIIIIIIII Ilufuu IIIIIIIII mdu11 IIIIIIIII IIIIIIIII IIIIIIIII 1111111i 11V1,�CI . � as�.�7:� SUBTITLE PLANS - AREAS 6 & 7 REIV CITY OF CETUKED WIIA JUN 1 7 1996 PERMIT CENTER CONTOUR INTERVAL = 1' DATUM: USGS MSL = 0.00 CITY OF TUKWILA DATUM NAVD = MSL + 3.6 FT 20' 10' 0 10' 20' 40' SCALE: 1 " =20' L%= o&t • ,BLE DUWAMISH WEST RIVER BANK STABILIZATION CIVIL YARD OXBOW FACILITY DEMON SUPPORT UST REVISION SHEET C83 400 90. DCA -96024 D00 NO. c0. N0. �------------- ----�------����==~^-`�4--------`===,=--===�==-�------------- -_ SEE SECTION B -L�-------------- L------ �--___- -__--- ________________ _ ---------------- ---- ... ..�-�--_' _---_-_--_-_--_---_____ -- ----- ---------------------- �� o`� ��np APPROXIMATE __-----'___--_--_--_--_--_--_--_--___ --_--__-___ ----------------------------.---------------7�mUum�r---- - - � - _ -------- - - - - ROCK ��- �K - 14 13 12 1- -- _ �_ 1 m » n 2 -3 _-- -- ---- _-- ---_--- �-- -- - --- --- ------- --- �- _-~-- _�-- _'�---�- - �. z _-- -- �_- m_- --~ -�- --� -�_-� -_ --_' --- __ `- - - ---- ---- - --__.-�---' - ---- �-- -_ --__ -_----�--- -- -__---- --�-_- ---� -�_-� ---_--� -�-----_ �----_ ---r� ------------� a��- e _VAPPMX,IGH WATER VI - -_---_ --- VEL MIN SECTION — AREA -- _ 1 SCALE: 1"~* HORIZ r~*VERT EXISTING BANK 14 13 12 11 10 9 o 7 • 6 5 4 3 x 1 o 14 13 12 11 10 9 n 7 6 5 4 3 2 1 0 -1 - 2 - 3 - 4 -5 - 6 .~ -~' ` ~~~�~~ `' -- ,. � ~ -~�~�'�� ` - -___--_ _-- ___-___-_____ -------------- _ _-- -------_----�~4Z ----------------- J� ^��-_----------------------------- _------_--_----�.�---=~~�-----_--_------_____ -_ --- „., /`. --PROPOSED ------------'------ �- �mm� _--_--- ---_--_-- ----------��="�=`-'----=^��=-----`���-=---------- -------------------'�----- - -_ --- --- .~ _" --'---------------------- PROPOSED BANK__--_-- _--_--_--__�---_ --��~'--- �----------'------^-----��8�N��um�---_-- ~~...~ wuw�.K �'~��' r-��- SECTION — AREA 1 SCALE: r=4' HORIZ • C8OiC500 `~. ""•■ _ � 4" GRAVEL MIN SECTION — AREA 1 SCALE r~* xomz QUARRY --�vm�- --------------' ------------- ____ - __-_- _-- • SECTION — AREA 1 SCALE: 1"~+ HORIZ c���o �~*�� .^� • UPSTREAM - A---------------------------------- ..c--DOWNSTREAM r_SEE SECTION s„s_ VAPPRDX ` .... ....� _-___--__-_--_----_---'__-_---- _-__--_--_-'----_--_---��___--__,---_ APPROXIMATE IJMITS m----'---- ---------- -----'----- 12 2APPROX HIGH WAgR LEVEL BUTTON 14 13 12 11 10 9 14 13, 12 11 10 9 8 7 6 5 4 3 2 1 o —1 -2 -3 - 4 - 5 - 6 ----- ---------------' __ _--__- __ -_ __ �-_ -_-' -_ - __ -_ _- _-_ __ - v r m � � 0I7 817‘ LE 017, tlE EE- ILE (lir 411 WI LIT 011 l ----___=---- _-_ ----- - -----~ -' C8100 ' ~ ' � '---_-. ��--_-� ' � � -.--_-_-- -- --- -- ----'-�---___-- ---�--- MEL SEA .... _ ^ ` /�\ ` �obo00 APPROXIMATE LIMITS _-_ _- _ _ - - - SECTION — AREA 1 SCALE: r=4' HORIZ 14 13 12 11 10 9 8 7 6 5 4 3 2 o -1 -2 -3 -4 -5 -6 __--___--_--_--_--_--______------__--_--___--___--___- '--_---_----__--_-__--_--_--_____-__- EXISTING BANK - --__ _-____--___--_—_---__ DOWNSTREAM - SEE SECTION G � � -_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-____ --- - _ � -_ - _' ` _-_-_____-_-_----____-_ - ----------------------------- _________________________________________ ________________ PR�����----,--------���� mm SECTION �� -� ' _ AREA 2 SCALE: 1"~* HORIZ C8i0 C500 __2����������`���^ ^---------- '�-- ----------------��mm���c�nr---- - - ----'--------------------- _- _ - - _ ,-- -- � ____________________ IL --------����� nPALLS . --_--_2 -__-_--_--_-__--_-'----___ _ `- _---_ .��-----_---_----2 -_--------------�r�a��N-�------ - ~��� '---~=��--------------- ---_--_--_--______----_--_--_--_--_______-�-- ________________ -_'___--__ ---_-�----_--_______--_--_^-_--_____--_-- ---_--_--_--_--_---�_-_______-_-__--__-_--_-__--_----_._------__ PROPOSED BANK_ _-____--____________--____ -- [- --_��- _ - - _ � � � _- _ SEC—(]N — AREA 2 SCALE: 1"~* HORIZ C8I500 1"~* VERT \ -� ~ FOR VEGETATED ~~~ DETAILS, SEE SHEET LS500. ,A FOR SEED AILS, SEE SHEET LS500. REVISER *w REVISOR rt AirOSEZAKO FACILITIES DEPARTMENT ' ' � SECTION — AREA 2 , ` -_ " SCALE: 1"~,xonIZ CIVIL * 2' 0 2' 4' 14 13 12 11 10 9 8 7 6 5 4 3 2 o - 1 -2 - 3 -4 - 5 -6 8' istto-out -' 1":.• CROSS SECTIONS - AREAS 1 & 2 FACILITY DESIGN SUPPORT SYMBOL DATE EXISTING 130TT DUWAMISH WEST RIVERBANK STAB|LIZATION YARD OXBOW SHEET n� ������� ������ * OX-96024 CORP HO. 96024C1\62405000 _- |q1'v|',|',D111111'|'111' |''['|'C[/T' ` 14 ---------------------------------------------------------------------- 13 12 - - - -- ��c------------------------------- ------------ ----------- - - - - -- 10 --- - - - -- —.....----...—,77___..1,„_____ - - ----------------------------------- . 47 EXISTNG BANK ------------------------------ 9 ^--- --- - - - -`� 8 \ --S,—....S,,------------- - - --- ------- - - --- -y - APP r3 X H WA R LVEL 7 _ 6. '----------------------------------- 5 PROOSED BANK.---_— ----- --- ------------- 4 ----------------------------- —4 GMVL MIN SPQS - c7 ' - 1 APPROXIMATE LN111S ..".• 10E torlDMIN t c -1 ------------------------------- - - - - -- i ---'----------=`—..------- - 2 ----------------------- - - - - -- - -3 ---------------------------------------------- •------------------ - - - - -- - 4 ---------------------------------------------------------=------------ - 5 --------------------------------------------------------=------------- - 6 ---------------------------------------- - - - --- ----------------- - - - - -- 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 - 1 - 2 -3 - 4 - 5 -6 SECTION - AREA 3 SCALE: 1 " =4' HORIZ 1" =4' VERT C810501 IXISDNG -- - - - - -- - _ _ ♦ UPSTREAIA - SEE SECIKIN A &� - -- ♦ DoiTs REAM - SEE SEC110N B ___________________________________________________________ 37APERgx HIHI ygER 1, 14 13 12 11 10 9 6 7 6 5 4 3 2 0 -1 - 2 - 3. -4 -5 -6 - --- - - - - -- (GG A'EL MIN, EMUS - ------------------ MAN SEA - - - -- - --------------- - - - - -- EXkAT ---- -- - - -- -- OF OF EXCAVATION PROPOSED BANK - ------ --- - - - - -- _ - -- • SECTION - AREA 3 SCALE: 1 " =4' HORIZ 1" =4' VERT C81 C501 14 13 12 11 10 9 8 7 6 5( -4 -5 -6 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 - 1 - 2 -3 - 4 - 5 - 6 •$! ` — IXISIINC BEYOND ---------_-------------- ____________ ��Q''UIN;14p--- - - - -- -- -- - -- -- $/APPRQX FI�I,H WA1ER LEVEL PROPOSED BANK -- - - - -- -- 4CRAWL MN ARMOR APPROXIMATE LIMITS 15F1XVT6F- - ------------ _' R- 0 M - -�—� 14 13 12 11 10 9 8 7 SECTION - AREA 3 SCALE: 1" =4' HORIZ 1' =4' VERT - - - -3': C81 C501 UPSTREAM - SEE SECTION ------ - - - - -- -- - - - - -- DOWNSTREAM -`SEE SECTION B -7! - —�- EXISTING BANK -- --- - -- -- -- ---- ----- - - - - -- 6 5 ------------------'- z--- 4 ---------------------- 3 -------- -------- - - - - -- - -- 0 - 2 - 3 -4 - 5 -6 • - O B- MIN 1XR ------------------- __ —_ -- APPROMIAI_1 4MRS -- -- OF EXCAVATION - QFOR VEGETATED GEOGRID CONSTRUCTION SEE SHEET LS500. DATE REVISOR BY BOE //VG FACILITIES DEPARTMENT SECTION - AREA 3 SCALE: 1" =4' HORIZ 1 " =4' VERT ACCEPTABILITY THIS DESIGN AND OR SPECIFICATION ISM D APPROVED BY DEPT. -DATE C81 C5 1 gams BtAZIMII --- 9 - - -- ---_-- TOE _ +1 ----- _� -ROCK f? - - - - -- — --- 14 13 12 11 10 9 8 7 6 5 4 3 2 0 - 1 -2 - 3 - 4 - 5 - 6 14 13 12• 11 10 9 8 7 6 5 4 3 •2 1 0 -1 -2 - 3 - 4 -5 -6 CITY CF TUKWILA JUN 1 7 1996 PERMIT CENTER 4' 2' 0 2' SCALE: 1 " =4' Vats • oq�� CROSS SECTIONS - AREA 3 LAST REVISION 96024C.L \624C501D RECEIVED JUN 17 1996 PUBLICC WORKS 4' 8' AN rn tc FACILITY a DESIGN SUPPORT SYMBOL DATE CIVIL DUWAMISH WEST RIVER BANK STABILIZATION YARD OXBOW SHEET C501 ,51-RD or OX -96024 DWO NO. pill 2I ii 11111131 ' 11 ...1. I ii.i .� i,ji 4 I Iji l�r Iii 1111 11 111 iii 1a5� I 16 Of 17 91m u7- •.7 v 811 u1E 1uu1uulu3md.uu, lluu1m7_u1Zulu1uulu iluuluu1mi!iiii llu6 .1Zd_uulmiuuluuuuluL1uuhJm dul / 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 - 1 -2 -3 -4 - 5 -6 14 13 12 11 10 o o 7 6 5 4 3 2 o - 1 14 13 12 11 10 9 8 7 6 5 4 3 2 1 n - -2 - 3 -4 -5 -6 , -------------- -----�-- ���� OUMRY _PROPOSED BANK EXISTING DANK ____ Inealtig -- — SECTION - AREA 4 SCALE: 1"=4' w 13 12 11 10 9 8 7 6 .0 _--__ _____--_--_-----'---_---_--___ 3z momnumD.a*a ",~'onTRau- SEE SECTOR ^ _7 APnmx HIGH WATER LEVEL ________�_ DOWNSTREAM - SEE SECTION 13 QUARRY 7 ------ __--_--_-----o'-r MIN lYP ----------- — * R�--�___--__--_--_------___ -��- .......... SECTION - AREA 4 • C82 C502 TOE- _ _ _ _ _ _ _ _ _ : __ _________: ___ -___ —___ -___ -___ —___ -___ -___ _—__ -___ -___ 7: _-__ -___ __—__ _-__ __-_ _—____-___-:-___-___—__i_ ___- _____— __:_:-. ".—:- :— _:_:__-- li..-- _-_ _-_ E. .:_:=—HEHE _ROES____ 2.2:::;_,....,„ -----------------'---'---�----------------------[���7--------- ---'_----_________________________________________________ 14 13 12 11 10 9 8 7 6 5 14 13 12 11 m. 9 8 7 o, 5 4 2 o - 1 -2 -3 -4 - 5 - 6 14 13 12 11 10 9 8 7 _- � _-_ _ _ _ _ -_` _ ___ _ _ _ _ _- _ � _ - _ - __________ SPILLS -__—--___-- • ucatioN _ _ _ _ _ _ _- _- _- _- __- _ _ _- _--- __- _ - - _--- _- _- _- _- -_ _ - - - _ _ � ' _- --------- -------- -- - - - - - -- - ` SECTION _ AREA `7 8 !6 a _ - e | x• _ � __- _-_ - _-- _-_- --'_-- ___--_ _ _-_ _- - _ _- _- - _- - -_- _- ,-- _ _- - __- '- __- _- _------_ _- _- _- _- __--___- _- - _- ___--_- _- _--_�_ --- _ _- --_ ^--_ _- - -- - - ___________ _ -------- 12 o1 '` _ _____________________ ` - -_�_- - r _ ' - ~ -� ` _--_--_ ____- - `or� - __- - - - - - - � - - m -- - • 3 ' * o / __�---------------------------_-------'----------_---------'--__---------- -_ r�'�_-----_- - _ --�--^ BAN- _ -----�-^-�=-^-� _ _ QUARRY ' ~--_=-_c----- -- -_-_�--_�--��---�---��---��----_-�_ �---_----. -_-----� __----_-_-_-'-�--__---_---_ _ -- � _- 4 x -. 1 mmn 0 '=�� __-- -1 ----------- ----___--__-_ --_____--_--_--_--__- o o _ ~ -4 -5 -6 - - - _ - - _ _- - __- _ -_ _--� - - - _ _-_ - _ - _ _ _—_- - � ~ -* SECTION - AREA 4 SCALE: ----- -___ _-�--'-- - _---------__ -------- ------- -- - - -- - ' --_ �-m- -- - � - --_-__ _ - -_ - -~---_- - - - - � -_ ----- � � � -__-_-_--- QUARRY _- __-----_---___---` ` --_----^ ------------ --_- --- --- --- -- - --- --- __--- '--_ --- --- -___-- - --_� m--_-�--- - -_-- - - -' - --_ - _. � `7_ SECTION - AREA 5 C82 C502 SECTION - AREA 5 SCALE: 1"=4' C8I2 C502 - - - /k CONSTRUCTION DETAILS SEE SHEET u500. / FOR SEEDED AREA DETAILS SEE SHEET LS500. 'mE xm PENSION BY wnINm -DOE pw mom BY AIWEZAVa FACILITIES DEPARTMENT ` _------ - - - - . = � - -- ---__----__-__---_--=`�,_� -------------------- • EXISTING BANK - ----- QUARRY _3,5, — 5 - 6 • • RECEIVED � 'JUN 17•1996 • • t --�~��� ________________________________ PROPOSED BANK ---'__2 OHIV•EL +5.10 _____ �. TUKWILA PUBLIC WORKS _7 100 Y rLOOD.EL +6.f --------------- -P---H_ 14 13 12 11 10 9 �_-__----"��--_---- ■NVNI^ ■n RVD - -~- -_. ------------ ExIst irovecclic -----§���� - -_-_---------------�------'m�xum�~n -- ------ '�='--- �~-= - --- --------------�m�x�mroumr- TO MATCH SLOPE OF ��[7|ON - ��r� � ---'-'' '`^~' ` SCALE: � SUBTITLE MILLW _WALLS_ ���SA JUN 1 71996 PERMIT CENTER 1"=4' � mft '' . C112_1902 ~^. 4' 2' 0 2' 4' 8' MI MEI MI MI I In I SECTIONS - AREAS 4 & 6 DUWAMISH WEST RIVER BANK STABILIZATION CML YARD OXBOW LAST REVISION SHEET FACIUTY DESIGN SUPPORT MANX DATE Y��������� ����� = �NO,mCA-96024 DM NO. GNP NO. 96019C.L 619C502D { , 1M11.1/yyy Y1qTqy p � ' ( ,' 14 13 12 11 10 9 8 7 6 5 ^ ' � -- ` • _ _ - - - -_ -- - _ - - _ _ -~=_ - - _ _ - - _ - _ - - _ _- -- - _ - --_ -- _ _ _ - - _ - _ _ - -__-_____-___-__-_--_-___ %- - �_ - -^ ------'---. -------~~-~-~-~ � -�-_=.---.-__- '--_�--_-_--_-_-_-�------'_-_--------_-�_-- - - _ --�_--_-_-�-�---------�-_ --_-�~ --_�. __--••• _--_--__ 2.0°=.~ zupmmeumm�aw� ' • - -_` - __� -� -- - - l - - - - - - � � � T �»�����E-C6�l------------ � �'-- - -_-_�'----_- . _ 4 GRAVEL MIN - (Mr MI • -�� �---�-���------- ^ u�� �'�.-� m�-�� 4 ' ~~ - ^ ___-_-_--- 2 �------ - , ---------- ----�- ___�� ��.-~_--_-�---_-___- -------�-----���------�. ----------"°--,=--°ax_----�-----�----_ - ------4�S�� ��J �_--m _ -__--_�2-�-~-.-_.,zww-u_aa_--_ --------------•------------- -_--_�----- -` - --___' _@��@@��i � -_-__---�--_-_----____-_- - -__- -----_---�-'z==- .---_- `"_-__' _----_---ww=� �-__�_ _ - -- _ _ _ _ ' - - - - _ -- _- - _ - - - - _ - -- _ _ _ _ _ - , 'APPROVED BY DEPT. DATE _-_ APPROX HIGH WATER IEVEL PROPOSED BANK 2 C+114=EL +5.10 - - -_ - - ~ � - - _ -- - _ - - _ _ - - _ _ _ -_ o -1 -2 3 - 4 -5 -6 14 13 12 1 1 10 9 8 7 6 5 * 3 2 1 0 - 1 -2 -3 -4 -5 -6 SECTION - AREA 6 • SCALE: r=*xomz r=4' VERT _ _-- SECTION - ' AREA 6 SCALE: 1"=.4' HORIZ 1"=4' VERT -.3E. MEAN SEA LEVEL ---- - _- _- _- - _- - - - - - - - wT ` - - - - - - - - 8.1903 ________________ -_--_-_-_---_- -_- 'SECTION - AREA 6 SCALE: r=4' HORIZ C8bs03 1"~*VEm • / . �----_-�----�_-�-_-- ----- ---�_�-�--' -- �_-- �_-_-~'---_------- -_- �---� ----_--------,- --- _--_- __-_ ----- _---- �__-_ -8 ----- -- ___-_- _---- ---__----_ -�---�- _--�- - - - - -� _- --�- --_'-p -�----- ---�---- _---- ---_� -- ------ --_--'-_--_-`_---_ � -- ---�--__-_ -_� -- --- _-_ - ----- _---_ -- ___-_ ----_ ' _�-- -- ------------_----__- -� - --` ----- -_- ---- ---- - _--- ---- ---7' _- -- _----_-- _-_-- ---- --- _-_- - -_---- -_- _ -- - ----- �-- - - - - - - -__-- - _ --- - --= --~--_~ _ -- - - -_ -- _-~ - _- - -_ -• - _ ..... ----- 7 _ -� ' �- -� E'� � �- _- _- -- -- _- _- - _- -- -- _- -- - �__-_- -----�-- --- -_-- ---- --- _-_- -----_ -- _--- ---- ----_ -- ---_- -- - -m-- -- ---_ -.E� �� -- --__ , - ^-~ � ~ -- -_ _ - - - - -_-__�� -----�- - -----_�- - -_----�- - - =- - -- � -� - �--- _ ° � - �-- ' � -�� � ° . -� _ � ' __--__ _ _ -' -_ - _- _ _ -- -- __- --------- __ --_------- -__- - ---_-- - __ - - __ - --'- -- - __ - ---_- - __ - -- - - __� - - - - -- ---_- - - - - __ ---_ - -__ -_- --- - - ~ ~ -~ _-_-_ ' -- ___-_-_-_-_-__�--_-_-_- _-_�_-_-_- V~~. ~~.~~.~ V°="°==�" LEVEL _ --- -_-��-- ---_____-___-_-' ^������ ��-�- e���M� _-__-_--------_--_-°-=^� ' -____-- - . �� QUARRY - --- --�- OF EXCAVATION � ROCK ~` • � 210 ==OD=EL4= ME,QBELLBANIL. APPROX HIGH WATER LEVEL UPSTREAM - SEE SECTION D DOWNSTREAM - SEE SECTION E --___ --��_ __'_�-- ��- �_�--�_ _�-_-�-��- -----�-_ --�-_�-�-�- -----�_� --L mm -__L _OF EXCAVATION ��-' - - _ -_ _ _ - - �- _ - -- � - -_ --_ - - - _ -_ - - '' � - '_ � --� - - _ __ � `--� _ o O H1V ' ' ' ' + �5.10 . ;Uoo • - - _ _ - `----� - - - _- -_-_- --- -� c ' � -- � - ----- ---. -, - - - - - - --- � ' � _-- _ ------- '-- ------ � - � - ^ - - _- �- - - - --- - - - - - - - -- ---- - - -_-- ---- _---- � ------- ---. - -- �- - _- - - - --- _- - - 2 MEAN SEA LEVEL s• 2 MEAN SEA Lea ------- --- ----= ---- ---------- -- SECTION -_A _ A -- - -- -- - -- -- - _ - - - - - - - - - - - - - - `--c _' *, �� - �� �------- - ---------- ____------ � - - - - ------ ---_-__--- ---- -- -- ------ - ------ - - - . -� - A 7 _- S AREA 7 ',31' r~4' VERT --�� � ' ' - SECTION AREA 7 L , � um�o r~*xono o��—^ 1"~4' VERT « wo SCALE: 16=4' HORIZ AMMON � FACILITIES ospxmMEN/ ` ACCEPTABILITY • A SPECIFICATION "APPROVED ' ����HORIZ , = APPROVED C8I3 C503 �� FOR VEGETATED GEOGRID CONSTRUCTION RECEIVED JUN 17 1996 PUBLIC WORKS 14 13 12 11 10 9 u 7 6 5 4 3 2 1 o -1 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 - 1 -2 -3 -4 - 5 -6 ��� u JUN 1 7 1996 PERMIT CENTER 4' 0 7 f 8' L%-ootkl CROSS SECTIONS - AREAS 6 & 7 DUWAMISH WEST RIVER BANK STABILIZATION CIVIL , YARD OXBOW LAST REVISION SHEET FACIUTY DESIGN SUPPORT SYMBOL DATE Y��������� &���� ��NO' OF COMP NO. DWO NO. 96019C.L \619C503D clt 111111 II 1111111 I ' , -'` 2x4 DOUGLAS FIR OR EQUAL • FILTER FABRIC MATERIAL MIRAFI 100X OR APPROVED WITH GALVANIZED 14 GA STEEL WIRE CLOTH, 2x2 MESH UNDISTURBED AREA 1' TO 1 -1/2" WASHED GRAVEL T OR PEA GRAVEL `* NEWLY GRADED OR DISTURBED AREA 2x4 DOUGLAS FIR OR • ,APPPROVED 0 4' -0" OC TEMPORARY SILT FENCE EROSION CONTROL DETAIL SCALE: C80 -C83 C504 5' 20' MIN PLACE (5)3' -5' MIN DIA. ANCHORING ROCKS ALONG EXPOSED LENGTH OF TREE TRUNK ON DOWNSTREAM FACE. ' rail.' EL 5.10 EXISTING BANK 18' MIN 18' DIA 25' -30' LONG TREE TRUNK W /ROOTS. EMBED TREE TRUNK INTO RIVER BED BELOW CHWM. TREE TRUNK SHALL PERTRUDE AT AN ANGLE OF 2' TO 10' DOWNWARDS TOWARD THE RIVERBED AND AT A 30' ANGLE TO THE BANK POINTING DOWNSTREAM. ARMOR ROCK APPROXIMATE LIMITS • OF EXCAVATION 1. ANCHORING ROCKS SHALL MEET MINIMUM DIMENSION REQUIREMENT IN ALL DIRECTIONS. 2. 2' LAYER OF HEAVY LOOSE RIPRAP SHALL BE PLACED OVER THE FULL LENGTH OF THE EMBEDDED LOG. LARGE WOODY DEBRIS DETAIL SCALE: 1 "a4' Dr DATE snA ROSIN AWE/Ala FACILITIES DEPARTMENT C80, C81 C5 4 TOE ROCK ACCEPTABILITY NS DESIGN AND OR SPECIFICATON IS DETAILS RECEIVED JUN 17 1996 TUKWILA PUBLIC WORK: • RECEIVED CITY OF TUKWILA JUN 1 7 1996 PERMIT CENTER 4' 2' 0 2' 4' 8' • SCALE: 1 " =4' 1.56 Valk . LAST REVISION FACIUTY DESIGN SUPPORT 96024C.L \619C504D DUWAMISH WEST RIVER BANK STABILIZATION YARD OXBOW SHEET C504 Joe No. oP Tie N0. DCA -96024 COMP NO. 1111111 III III I fI III III III III III III III Iji IIr FII1II III III IIr III Ijl III III III 11I ! I .I • 12I . I I 13I 1- ...I . I.,4I' >�� `'. • OIf: fIZ NI7� LI7 .._91g . AIZ • Fj7. LIT -ZIZ -• ,11Z. _QIz �g1 NIT LII 91 RR RldRll uulim uuluu mimiRRluu uuhul uuluu uulull uurul uuhul uuluu uuluu uuluu mlluu mdui 0 till. ' -4M, '7 q,,I `` R. AREA 6 \.L_ - I 13+37.71 BASELINE PK NM. VA1H CON1ROL FLASHER FOUND BARGHAUSEN ENGINEERING POINT 505 A ' a� • ti AREA 5 9 +07.99 BASELINE_ HUB & TACK \ 100 SO 0 100 200 SCALE: V • 100' CONTOUR INTERVAL • 1' DATUM: USES MEL 507 - FOUND - RAILROAD SPIKE WITH SCRIBED •X' 1006 - FOUND CASED MONUMENT ESM CONTROL TRAVERSE 1002 - SET REBAR WITH RED ESM i ' CONTROL CAP. POINT IS LOCATED 6.70' NORTH OF SAN. SEVER MANHOLE AREA 4 5+79.03 BASEUNE REBAR RED CCN1ROL AA 1005 - SET REBAR WITH RED ESM CONTROL CAP. PONT IS LOCATED IN THE CENTERUNE O 16' WIDE PATH (12.2' TO UGHT POLE) BASIS OF BEARING AND VERTICAL DATUM ARE FROM THE BOUNDARY AND TOPOGRAPHY SURVEY PREPARED BY BARGHAUSEN CONSULTING ENGINEERS INC. FOR THE BOEING ACTIVITY CENTER, DEVELOPMENTAL CENTER SEATTLE WASHINGTON. SEE SHEET C9, JOB NUMBER 84021, DRAWING NUMBER 109 - 000 -1146 DATED 12 -21 -96 NOTE; DATUM FOR THIS PROJECT IS BASED ON NATIONAL GEODETIC VERTICAL DATUM (NOVO) OF 1929. DATUM FOR THE CITY OF TUKWILA IS BASED ON NORTH AMERICAN VERTICAL DATUM (NAVD) OF 1989. TO CONVERT NGVD 1929 TO NAVD 1989 ADD 3.60'. REVISION 2 +00.00 BASELINE PK NAIL MATH CON1ROL FLASHER 1007 - SET PK NAIL WITH ESM CONTROL FLASHER / / / 91141 0+00 BASEUNE HUB k TAO( KATR 3 S 1001 - FOUND MONUMENT AT THE EAST OUARTER OF SECTION 4 PONTMIN FENCE LOCATED N AT THE ANGLE 1000 - SET PK NAIL VATH ESM CONTROL FLASHER yf� / AREA 2 1 A INDE)t PLAN KALE: 1 • 100' REVISION t003 - SET REBAR WITH RED ESM CONTROL CAP. POINT IS LOCATED 3.5' FROM GUARD RAIL .1004 - SET REBAR WITH RED ESM CONTROL CAP. AIWA FACILITIES DEPARTMENT CONCRETE PIPE WITH CAP I.E. -1.19 TOP OF BANK 9.8 8 9.6 • L. -5 -' ,\ \ \, \ `\\ • f \ 131 j,di'▪ ,~\ , \� \ ,,\... • \. \� @.. x -5.3 9.9 PATH 12' WILLOW 99 9.8 -TOP OF BANK NOTES: x -9.6 x -9�-9.1 ' -9.1 -5.4 x 1. RESTORE LAWN AREAS .� \ \ x �,�^ m 4.\ DISTURBED BY OOt151R1K'Ti ION. 4.5 x � \ . 2. RESTORE & REPAIR IRRIGATIC.4 SYSTEM DISTURBED 501'-- -- �\ 9 \\ x -6.3 20 10 0 n B'f CONSTRUCTION. PROTECT EXISTING TREES TO REMAIN. 4. STRIP SOD TO 6' DEPTH UNDER NEW PATH. TOP OF BANK 20' APPROXIMATE LOCATION OF EXISTING PATH & IITREE (FIELD VERIFY) 40 SCALE: V • 20' CONTOUR INTERVAL • 1' DATUM: USES MEL 1 N AND If MAPLE 2'CLEAR' . 20'IREE \ 3 9@ TOP 44 8.5 - 3.9 PA TO\ LAMM • 5. x 4 \ \ + -G.3x\ -4.6 x X -9.6 x -11.7 x -11.4 x -11.5 x -11.4 :1 -9.3 A;.a I. . 1,, M -1 S'.11,1 • 9 +07.99 BASEUNE IR1B t TACK. APPROXIMATE LOCATION OF STING PATH. UGHTPOLE & 12 12""&20• TREES (FIELD VERIFY) 10.0 I 0. 0.5 Y. 10.5 LSS1 ISSO :1 x -9.3 -10.0 O \ x -10.1 Y. -7.3 NOTES: 1. RESTORE LAVI N AREAS DISTURBED BY CONSTRUCTION. 2. RESTORE & REPAIR IRRIGATION SYSTEM DISTURBED BY 3. STRIP SOD IO.S' DEPTH UNDER NEW PATH. APPROXIMATE LOCATION OF EXISTING PATH & EDGE OF PAVING (FIELD VERIFY) 23+02.79 BASEUNE PK ODNi o 1M1 ON 13.6 _ -5.1 �x-- -6 +F-... ..::- -�._'•- __`'.�Y -.- ..�_.. S.G r' •_. " - -• '+. ` .- x -13.3 -4.5 x \, •- ._...'�.�'.'••..,.. -3.8 x . .9''r .. ............�'-••... �t�-- \y.. 8$`\. R -12.7 + -3.6 R ■55' CONTRACTOR SHALL SMUT AND REMOVE EXISTING ASPHALT & ROCK BASE TO UMRS SHOWN. OWNER MALL REMOVE STORED STEEL STO S) MS & RAGE 0 AUBURN, WA.98002 0 BELLEVUE, WA. 98007 0 EVERETT, WA, 98201 KENT, WA.98031 0 PORTLAND, OR. 97220 LI RENTON WA , 98055 • SEATTLE, WA.98124 1.1 TOP OF 8 E OF ASPHAL % 10.7 AV` x ------------ -19 x ' , -33 4 - 3.8 ila 1, _ .rr,3- • \\ 6 11.8\5 0 -9.3 REMOVE EXISTING PATH MO CONVERT TO LAWN. R•55' 13+37.71 BASELINE PK SA . 1111.1 00MSOL PLASM PLAN AREA LSBO LSBO SCALE : I' • 2D' PIIOIMNIOIAL .TM! w-- 20 10 0 20 RECEIVED JUN 17 1998 TUKWILA PUBLIC WORKS 40 SCALE: 1• • 20' CONTOUR INTERVAL ■ 11' DATUM: USES MSt>;REC IVED OF TUKWILA JUN 1 7 1996 APPROXIMATE LOCATION OF EXISTING PATH. UGHTPOLE & EDGE OF PAVING (FIELD nRUCEAlk DEES& ASSOCIATES x 10.9 ACCEPTABILITY THIS TI A . EFEDlnana 12 /PROVO BY PERMIT CENTER DATE TFILE PLAN - JOGGING PATH RELOCATION ISa1114a■11DOI Pep_ LAST IrVI.IOI DATE DUWAMISH WEST RIVERBANK STABILIZATION• CIVIL YARD OXBOW LS80 OCA -96024 6A. No. 05411L500.0114 541J06.12.E6 111111I IIIIIfI +NINTH ill IIIII�Illlllllll�ll III 111111I'! i'111 111 VIII I I I01: (37 89 LB; _DZ. - 7.7.•_1 , _OT �(�[. 8I LI UI IIIIIIIIIIIIIIIIIIIIIIIIIIIIIhllllllllllllllllllllllllllllllllllllllhllllllllhlulllu 'lllllllllhllllllllIHi' it IIII lmi!ill'I 111111 REUTCD3STIND: CINDER RAGING TRAIL VARIES RESTORE LAWN ANO REPNR/ADJUST IRRIGATION 14 NS AREA (mock). IiSEALL TOPSOIL PER© TOP OF SLOPE ■TOP OF VEGETATED CEOGM pp LJVE comes/0)1H LAYERING (TIP.) SEE BRUSH LAYEI INO., : PLANINiG OETAL COIR CEOTEXTIE FABRIC RIP -RAP SLOPE PROTECTION. SEE SHEETS 010-83 & 0500 -503 ORDINARY INCH WATER MARK NATIVE RNEREINS SOILS MATERIAL TOP OF R P- RM•TOE OF VEGETATED GLOMS (ELEV.4.0) n VEGETATED GEOGRID TYPICAL SECTION LsesD um NOT TO SCALE . . PROMIMMIMIN '•■••- 1 -1 I I -1 I I -1 I I -1 I I- 1 -1 FINISH GRADE SUIGPADE TOPSOL (SEE SPECS.) ROTOTLL 2' DEPTH OF TOPSOL INTO TOP V ADDING REIMS 4'� DEPTH OF TOPSOIL. TOPSOL ROTODUED W/SUBGRADE 111 ON -SITE sOL 1. INSTALL TOPSOIL AT ALL LAWN SEED AREAS. N LAWN 2. COMPACT SLIBORADE !. TOPSOI /110TO11LLED SOD TO B5% DENSITY IN ALL LAWN MEAS. F SUTERADE DENSITY I5 OREM THMI 1151 IN LAWN AREAS CONTRACTOR SHALL PLOW OR 'RP' SIIBORAOE TO A 2 FOOT DEPTH. 3. FINISH GRADE IS TOP OF CRUSHED CINDER PATH. n TOPSOIL INSTALLATION SECTION woo NOT TO SCALE TOPSOIL OR ON -STE SAND OR SILT. BACKFNL MATERIAL 1x2 1000 STM E311 CYP 16f ANN. LENGTH. AT 6'O.C. FULL LENGTH Col GEOTSCHLE MATSOL RMERBNA . SONS 1 HOOKER WILLOW Sok hooNodnana RED OSIER DOGWOOD Canty atolonVara f air& ALL 3 SPICES. 2. THOROUGHLY WET EACH LAYER OF BRANCHES & BACKFlLL WARM. BRUSH LAYERING (SEE PLANT UST) TIP WEND: DIA. MIN. 1 0'DIM. MAX. BUTT END: 1.OIA. ANN. (lYP) NAME v ' SONS SECTION BRUSH LAYERING PLANTING DETAIL LSIlOOwoo NOT TO SCALE B' MIN. = LUNCH ADJACENT EXISTING PATH WIDTH -1�1�11'II 11=111- 1 =1111= 111 =I1 =1 III = 111E - =1 1 - = 1 -1= 111 -111 -111 -1 , 1= j =1 - �.Il1�II Il TT BRUSH LAYER 3/4 1/4 PLACE BRANCHES CRISS-CROSS TTERN 6 BRANCHES PER UN. MINIMUM FT. EDGE OF FILL (SURFACE OF SLOPE) PLAN VIEW': BUYER 4' MIN. COMPACTED DEPTH 1/4 MINUS CRUSHED CINDERS 000 TREATED HEADER rr�Inun IaulLie ( TOPSOL) rl 1 -1 1 -11111 171 1= H I11 — 2x2x111' LONG TREATED =M= WOOD STAKES 0 4' O.C. l l =1 I 1 SUSGRADE: COMPACT TO 951 SON. STIR ILAIIT UNDER TRAIL SURFACES ONLY - BOEING REP. MUST � E DURING ALL PROVIDE le TRANSITION BETWEEN ADJACENT PLMIT1NG AREA GRADES AND PATH EDGE. MATCH FINISH GRADE OF PUNTING AREAS TO TOP OF CRUSHED CINDER PATH. n RELOCAIED CRUSHED CINDER PATH LSBOISM WALL .1.1 SAW REVISION . DATE FACILITIES P T 0 AUBURN, WA. 98002 0 BELLEVUE, WA . 98007 0 EVERETT, WA. 98201 0 KENT, WA..98031 0 PORTLAND, OR. 97220 0 RENTON WA,98055 • SEATTLE, WA.98124 roo►mIOUL STNP ACCEPTABILITY MIS Ot<i i a�ECV10AT101 IS APIIOYW N L'i(rW'll RECEIVFri JUN 17 1996 TUKWILA PUBLIC WORK:. RECEIVED CITY OF TUKWILA JUN 1 7 1996 PERMIT CENTER BRUCE DEES& ASSOCIATES .i.IIL..._ �IU "I PLANTING CROSS SECTIONS & DETAILS LAST I[VISICII STIMICI, Mgt DUWAMISH . WEST RIVERBANK STABILIZATION - DCA- 96024 -LS500 004IL000,a1Ei SAJ/00.11.115 NUT LS500 DCA -96024 ar 1ji I11 111 111 1'I III Ili ICI Ili 111 :IIi 11,1 111 IIl 1(I 111 Iil 111 iII I!I 111 111 111 Illl 11 ,r' .I 2i I: 1 131: i. I- ..!.,4I• 1 1.51 1 116 c.. 0(E fil7. 8IZ" 6I7. -.fl; 6I7 �' bIZ- •7,I7.•t -IIZ; _Qlr gII 8IT i 8II ml uuhui uiduu uuluu 111711111 uu11111 illllllll IIIIIIIII 111-11 II iiiiiiiii 111111111 illlliiii lllllllll uuhui uuluu uului