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HomeMy WebLinkAboutCOW 2012-08-13 Item 3A - Ordinance - New Speed Limit on Tukwila International BoulevardCOUNCIL AGENDA SYNOPSIS Initials ITEMNO. Meetin,g Date Prepared by Mayor's review Council review 08/13/12 B 08/20/12 BG 3.A. ITEM INFORMATION STAFF SPONSOR: BOB GIBERSON ORIGINAL AGENDA DATE: 08/13/12 AGENDA ITEM TTTLE Tukwila International Blvd Speed Study Ordinance Establishing New Speed Limit CATEGORY Discussion Motion Resolution Ordinance ❑Bid Award Public Hearing ❑Other Mtg Date 08113112 Mtg Date Mtg Date Mtg Date 08120112 Mtg Date Mtg Date Mtg Date SPONSOR Council Mayor HR DCD Finance Fire IT P&R Police PW SPONSOR'S After completion of the Tukwila International Boulevard street improvements, a full SUMMARY engineering evaluation of speeds, collisions, and volumes was conducted. It was determined that 35 miles per hour (mph) is a reasonable and safe maximum limit. Council is being asked to approve the Ordinance authorizing the lowerinj of the speed limit from 40 mph to 35 mph on Tukwila International Blvd between S 139 St and S 152 St. REVIEWED BY COW Mtg. CA &P Cmte F &S Cmte Transportation Cmte Utilities Cmte Arts Comm. Parks Comm. Planning Comm. DATE: 08/06/12 COMMITTEE CHAIR: ALLAN EKBERG RECOMMENDATIONS: SPONSOR /ADMIN. Public Works Department COMMITTEE Unanimous Approval; Forward to Committee of the Whole. COST IMPACT FUND SOURCE EXPENDITURE REQUIRED AMOUNT BUDGETED APPROPRIATION REQUIRED $0.00 $0.00 $0.00 Fund Source: Comments: MTG. DATE 08/13/12 08/20/12 MTG. DATE 08/13/12 1 08/20/12 RECORD OF COUNCIL ACTION ATTACHMENTS Informational Memorandum dated 08/03/12 Tukwila International Blvd Speed Study Synopsis Draft Ordinance Minutes from the Transportation Committee meeting of 08/06/12 1 2 City of Tukwila Jim Haggerton, Mayor INFORMATIONAL MEMORANDUM TO: Mayor Haggerton Transportation Committee FROM: Bob Giberson, Public Works Director 4P DATE: August 3, 2012 SUBJECT: Tukwila International Boulevard Speed Studv Ordinance Establishing New Speed Limits ISSUE Should the speed limit be reduced on Tukwila International Boulevard (TIB)? BACKGROUND After completion of the Tukwila International Boulevard Improvements (Phases I, II, and III), Public Works was asked to analyze the existing speed limit. Speed limits are set after conducting a full engineering evaluation of speeds, collisions, and related information. An engineering speed study was just completed by a traffic engineering consultant for the southern portion of Tukwila International Boulevard. The limits of the study are S 116 Way on the north and S152 nd St on the south end of Tukwila International Blvd. These are the same limits as TIB Phases I, Il, and III combined. The consultant studied speeds, volumes, and collision rates. The 85 percentile speed is typically used to set speed limits based on the theory that most drivers will travel at a speed that is reasonable and prudent for any given roadway segment. The 85 percentile speed is the speed at or below which 85 percent of the motorists drive on a given road unaffected by slower traffic or poor weather. This indicates the speed that most motorists on the road consider safe and reasonable under ideal conditions. ANALYSIS The 85 percentile speeds are shown in Table 1 (page 4) of the speed study. The 85 percentile speeds for the area north of S 139 are in excess of the 45 mph posted speed limit, while the area in between S 139 Stand S 152 St are below the posted speed limit. Collision rates for the limits of the study area are summarized in Table 2 (page 7) of the speed study. Data from the previous full five years was analyzed and the predominate collision type was found to be rear end and the typical location was at mid -block crosswalks, driveways, and approaches to traffic signals. To help mitigate the high rear end collision rate, the mid -block crosswalks near the 14300 and 15100 blocks are proposed to be retrofitted in 2013 as part of the new ADA crosswalk project in the draft 2013 Capital Improvement Program. RECOMMENDATION Council is being asked to approve the Ordinance which will lower the speed limit from 40 mph to 35 mph on Tukwila International Boulevard between South 139 Street and South 152 Street and consider this item at the August 13, 2012 Committee of the Whole meeting and subsequent August 20, 2012 Regular Meeting. Attachments: Speed Study Draft Ordinance W: \PW Eng \PROJECTS\H- RW RS Projects \TIB Speed Study 2012 \Info Memo Speed Study sb.doc 3 p Memorandum To: Bob Giberson, Public Works Director, City of Tukwila CC: Robin Tischmak, Public Works, City of Tukwila From: Jan Ciganik, P.E., P.T.O.E. Date: June 13, 2012 Re: Tukwila International Boulevard Speed Study Project No: 12028 This memorandum summarizes the results of a speed study performed on Tukwila International Boulevard between S 152 St to the south and SR -599 to the north. Data was gathered at five locations along the corridor, with speed and traffic volumes being recorded. This memorandum will discuss the following: Roadway Description Speed and Volume Data Collection and Results Speed Data Analysis Collision Data Results and Recommendations Roadway Description Tukwila International Boulevard (TIB) is a Major Arterial that consists of a five lane cross section with a two way -left- turn -lane or center medians between S 152nd St and the 12400 block and a four lane cross section between the 12400 block and the SR -599 interchange. TIB serves as a major north -south route providing access to SR -518 to the south and SR -599 to the north; the roadway length between these two interchanges is approximately 2.5 miles. The traffic along this roadway is comprised of commuter traffic from the surrounding neighborhoods. Land use varies along the corridor between commercial businesses located between S 152 St and S 139 Street and office buildings located near the 12400 block. 753 9 th Avenue North, Seattle, WA 98109 P: 206.286.1640 F: 206.286.1639 www klc )Cl.c,orn 5 PR OJECR END f KMVI BN IJC= OSt Vicinity Map 1"I u a 753 9th Avenue North, Seattle, WA 98109 P: 206.286.1640 F: 206.286.1639 ;wW.lnon.Cr 0 Speed and Volume Data Collection and Results Speed data and traffic volumes were collected at five locations along the corridor during late March, 2012. Data was collected for each lane utilizing separate counters. The locations studied are shown graphically in Exhibits 1, 2 and 3 in Appendix A and listed below. Site 1- Tukwila International Boulevard midway between S 150 St and S 148 St Site 2 Tukwila International Boulevard midway between S 146 St and S 144 St Site 3 Tukwila International Boulevard north of S 139 St Site 4 Tukwila International Boulevard north of S 130 St Site 5 Tukwila International Boulevard at approximately the 12000 block To evaluate vehicle speeds, multiple measures should be considered. These measures are included in Table 1 (next page) and explained below: Median Speed Median speed is the speed at which half of the vehicles travel above and half travel below. 85 Percentile Speed The 85 percentile speed is the speed in which 85 percent of vehicles travel at or below. The 85 percentile should typically be within 5 -10 mph of the posted speed limit. According to the Institute of Transportation Engineers, studies have shown that crash rates are lowest when drivers are traveling near the 85 percentile speed. 10 mph Pace The 10mph pace is a consecutive 10mph range of speeds containing the highest number of vehicles. Percent Flagrant Speeding The percent flagrant speeding represents the percentage of vehicle exceeding the speed limit by at least 10mph. I' 3 753 9 1h Avenue North, Seattle, WA 98109 P: 206.286.1640 F: 206.286.1639 www.koc ,i.corn 7 Table 1. Speed Data and Traffic Volumes Speed Median 85th 10 MPH Percent Flagrant Site Limit ADT Direction Lane Speed Percentile Pace (MPH) (MPH) Speed (MPH) (MPH) Speeding Curb 32.4 37.8 28.5-38.5 0.0% NB Median 34.8 39.8 30.0-40.0 0.1% 1 40 17,364 Median 33.2 38.2 28.3-38.3 0.1% SB *Curb 43.2 47.7 38.7-48.7 5.5% Curb 31.9 37.2 27.2-37.2 0.1% NB Median 34.9 39.9 30.2-40.2 0.3% 2 40 18,054 Median 30.4 35.9 25.7-35.7 0.1% SB Curb 27.9 33.9 23.3-33.3 0.0% Curb 41.4 46.5 34.9-44.9 0.7% NB Median 43.0 48.6 37.2-47.2 1.6% 3 45 12,841 Median 43.1 47.7 38.2-48.2 0.7% SB Curb 41.4 46.5 37.2-47.2 0.9% Curb 43.0 48.6 37.2-47.2 1.0% NB Median 44.7 50.8 41.4-51.4 3.8% 4 45 12,996 Median 44.7 50.8 41.4-51.4 3.6% SB Curb 43.0 48.6 37.2-47.2 23% Curb 45.8 51.2 41.4-51.4 5.0% NB Median 47.4 52.8 42.3-52.3 7.5% 5 45 11,481 Median 44.8 50.1 40.2-50.2 4.0% SB Curb 43.6 49.0 37.7-47.7 1.6% *NOTE: SB Curb Lane values at Location 1 were omitted due to apparent error in data collection. Median Speed The median speed is below the speed limit in all locations except for Location 5 in the northbound direction. 85 th Percentile Speed Locations 1 and 2 (with the exception of the southbound curb lane at location 1) have 85 percentile speeds below the posted speed limit of 40 mph. Locations 3, 4 and 5 have 85 percentile speeds in excess of the posted speed limit of 45 mph. 10 mph Pace Locations 1 2 have a 10 mph pace that is below the speed limit, while locations 3, 4 5 have a 10 mph pace that ranges above and below the speed limit Percent Flagrant Speeding Locations 1 2 have the lowest percentage of flagrant speeding, while locations 4 5 have the highest. The complete volume and speed data is provided in Appendix B. I' 1 4 753 91h Avenue North, Seattle, WA 98109 P: 206.286.1640 F: 206.286.1639 WW .kDG.00 Irt Speed Data Anal Figure 1 and Figure 2 provide visual representation of the 85 th Percentile and 5 Oth Percentile (Median) Speeds with respect to the speed limit. .111 50 40 2 30 Posted Speed Limit ---NB[urb W zu —NB Median —3BMedian Note: 10 Curb �BC b 3BCocbLuuc speeds at O Iumdool,,ro, om�oddmm 1 2 3 4 apparent data Location coDocti"ucours Figure 1—O5^' Percentile Speed with respect to Speed Limit As can be seen from Figure 1, the 85 th Percentile Speed is at or below the speed limit for Locations 1 and 2, then it rises above the speed limit for Locations 3 through S. INI] CL 50 4O r V) ism ]O Posted Speed Limit NB Curb 20 NB Median SB Median 10 Ln O, l 2 3 4 5 Location Figure Z-501h Percentile (Median) Speed with respect to Speed Limit Note: 85 Curb Lane speeds at Location 1 were omitted due to apparent data coHection errors As can be seen from Figure 1, the Median Speed is below the speed limit for Locations 1 through 4, then it rises etor above the speed limit at Location S. yne, |S 753 91h Avenue North, Seattle, VVA98lOy P: 206.286.1640 F: 206.286.1639 vmww.kon—corn Collision Data Collision data for Tukwila International Boulevard between S 116 St and S 152 St was provided by the City of Tukwila for the 5 years prior to this memo; January 1, 2007 December 31, 2011. All of the collision data has been summarized graphically, by location and type, in Exhibits 1, 2 and 3 as attachments to this memo. During the 5 year time period, there were 353 collisions, 168 of which occurred at an intersection and 185 which occurred between intersections. There were a total of 699 vehicles involved resulting in 104 injuries and one fatality during the time period. Collisions by Type As can be seen from Figure 3, the most common type of collision was Rear End. These typically occurred near mid -block pedestrian crossings, driveways or at approaches to signalized intersections. Right angle collisions were the second most common type, with 80% of them occurring at intersections. Head On. 4 Pedestr Cycli.. Involve( Fixed Object /Par[ ed Vehicle, 34 Figure 3 Collisions along TIB, by type 1'<-�c 1 6 753 9th Avenue North, Seattle, WA 98109 P: 206.286.1640 F: 206.286.1639 ww IE 1 Collisions Rates Collision rates were calculated for each segment and are provided in Table 2. The rates for spot locations (intersections) are reported in collisions per million vehicles and rate for roadway sections are reported in collisions per 100 million vehicle miles. Rates are calculated per the following equations: Collision Rates for Intersections Collision Rates for Roadway Sections Number of Collisions x 10 Number of Collisions x 10 ADT x 365 x Number of Years ADT x 365 x Number of Years x Length Table 2. Collision Rates by Intersection and Segment TIB at S 116 ST I 24 1 11481 1.15 Page 17 753 9 Avenue North, Seattle, WA 98109 P: 206.286.1640 F: 206.286.1639 www.kDa.com 11 Total Location Collisions TIB atS152ST 5 Between S 152 ST and S 150 ST I 40 TIB at S 150 ST 22 Between S 150 ST and S 148 ST I 12 TIB at S 148 ST I 21 Between S 148 ST and S 146 ST I 15 TIB at 5 146 ST I 25 Between S 146 ST and 5 144 ST I 25 TIB atS144ST I 21 Between S 144 ST and S 142 ST I 19 TIB at S 142 ST I 4 Between S 142 ST and S 141 ST I 6 TIB atS141ST I 3 Between S 141 ST and S 140 ST I 4 TIB at S 140 ST I 14 Between S 140 ST and S 139 ST I 5 TIB at S 139 ST I 4 Between 5 139 ST and 37 AVE S I 6 TI B at 37th Ave S I 11 Between 37 AVE S and S 133 ST 2 TIB atS132ST I 10 Between S 132nd ST and S 130 ST I 9 TIB at S 130 ST I 4 Between 5 130 ST and S 128 ST I 24 Between S 128 ST and S 116 ST I 15 TIB at S 116 ST I 24 1 11481 1.15 Page 17 753 9 Avenue North, Seattle, WA 98109 P: 206.286.1640 F: 206.286.1639 www.kDa.com 11 Intersection Roadway Segment Link ADT Collision Rate Collision Rate Distance (c /mev) (c /100mvm) 0.16. 0.12 I I 1052 0.69 17364 0.12 I I 316 0.66 0.12 I I 394 0.76 0.11 I I 717 18054 I I 0.64 0.12 I I 500 0.12 0.09 I I 210 0.13 0.04 I 316 0.60 0.06 I I 263 12841 0.17 0.39 I I 49 0.47 0.10 I 63 0.43 0.12 I I 237 12996 I 0.17 0.12 I I 631 0.70 68 TIB at S 116 ST I 24 1 11481 1.15 Page 17 753 9 Avenue North, Seattle, WA 98109 P: 206.286.1640 F: 206.286.1639 www.kDa.com 11 1 C 1PCX Results and Recommendations The speed, volume and collision data has been analyzed using the data provided, Engineering judgment and site visits. Recommendations will be provided based on industry best practices and field observations. Speed Speeding was found to be a minor issue at two locations along the corridor; locations four and five. The difference in speed throughout the corridor is likely due to the difference in land use and density of intersections and driveways. Surrounding locations four and five there are two signalized intersection and very few driveways, compared to four signalized intersections, eight unsignalized intersections, two mid -block pedestrian crossings and numerous driveways along the rest of the corridor. Possible corrective measures could include providing radar driver feedback signs that provide real time feedback to drivers exceeding the speed limit. This should also be supplemented with increased enforcement of the speed limit. Collisions Two locations were identified as having higher than typical collision rates for the corridor: TIB between S 152 St and S 150 St TIB at S 116 Way Field investigation was conducted to determine possible causes for high collision rates. Between S 152 St and S 150 St rear -end collisions comprised the majority (72.5 of total collisions for the segment and many occurred near the mid -block pedestrian crossing. The existing mid -block crossing provides overhead signage and in- pavement flashing amber lights. The in- pavement lights are not effective at alerting the entire platoon of vehicles as they are blocked by the vehicle stopped nearest to the crosswalk. Modifications to the warning system could reduce the number of rear -end collisions. Overhead and post- mounted rapid flashing beacons would provide additional warning all drivers in the platoon, reducing the likelihood of sudden stopping and rear -end collisions. Existing overhead mast arms could be utilized to reduce the cost of the installation. At the Intersection of TIB and S 116 Way, approach turn collisions were the most common collision type. Upon further investigation of the data, the number of total collisions (including approach turn collisions) significantly decreased after 2007. This is likely due to the conversion of the protective /permissive left turns to protected -only in the northbound and southbound directions. As a result of a site visit, it is recommended that the city install additional street -name and guide signage at the intersection. Additional signage could result in less driver confusion, leading to fewer collisions. Pa 18 753 9th Avenue North, Seattle, WA 98109 P: 206.286.1640 F: 206.286.1639 www.koo.com 12 AN ORDINANCE OF THE CITY COUNCIL OF THE CITY OF TUKWILA, WASHINGTON, AMENDING ORDINANCE NOS. 1875 §1 AND 1866 §1, AS CODIFIED AT TUKWILA MUNICIPAL CODE SECTION 9.16.070, TO ACCURATELY DEFINE THE PORTION OF TUKWILA INTERNATIONAL BOULEVARD BETWEEN SO. 139 STREET AND SO. 152 STREET WHERE THE SPEED LIMIT IS TO BE REDUCED FROM 40 MPH TO 35 MPH; PROVIDING FOR SEVERABILITY; AND ESTABLISHING AN EFFECTIVE DATE. WHEREAS, a portion of State Route 99, currently known as Tukwila International Boulevard, was turned over to the City of Tukwila in 2003 by the state legislature; and WHEREAS, RCW 46.61.415 authorizes the City to establish speed limits determined by engineering and traffic studies; and WHEREAS, an engineering evaluation of Tukwila International Boulevard between So. 139 Street and So. 152 Street was conducted; and WHEREAS, based upon the engineering evaluation, the City has determined that 35 miles per hour (mph) is a reasonable and safe maximum limit on Tukwila International Boulevard between So. 139 Street and So. 152 Street; NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF TUKWILA, WASHINGTON, HEREBY ORDAINS AS FOLLOWS: Section 1. Tukwila Municipal Code (TMC) Section 9.16.070, "Forty mph on portion of Tukwila International Boulevard Amended. Ordinance Nos. 1875 §1 and 1866 §1, as codified at TMC Section 9.16.070, are hereby amended to read as follows: W: Word ProcessingNOrdinances\Speed limit reduced on TIB strike -thru 7 -24 -12 BG:bjs Page 1 of 2 13 9.16.070 Thirtv- fiveF-orty mph on portion of Tukwila International Boulevard A 3548 mile per hour speed limit zone is established for both directions of traffic on Tukwila International Boulevard {Sfate —Re 9Q; between So. 139 Street and So. 152 Street n es G 6 +n nn;to C7n" 55N. Section 2. Signs to Be Posted. The Public Works Department is hereby directed to post appropriate speed limit signs reflecting the speed limit established in Section 1 of this ordinance. Section 3. Corrections by City Clerk or Code Reviser. Upon approval of the City Attorney, the City Clerk and the code reviser are authorized to make necessary corrections to this ordinance, including the correction of clerical errors; references to other local, state or federal laws, codes, rules, or regulations; or ordinance numbering and section /subsection numbering. Section 4. Severability. If any section, subsection, paragraph, sentence, clause or phrase of this ordinance or its application to any person or situation should be held to be invalid or unconstitutional for any reason by a court of competent jurisdiction, such invalidity or unconstitutionality shall not affect the validity or constitutionality of the remaining portions of this ordinance or its application to any other person or situation. Section 5. Effective Date. This ordinance or a summary thereof shall be published in the official newspaper of the City, and shall take effect and be in full force five days after passage and publication as provided by law. PASSED BY THE CITY COUNCIL OF THE CITY OF TUKWILA, WASHINGTON, at a Regular Meeting thereof this day of 2012. ATTEST /AUTHENTICATED: Christy O'Flaherty, MMC, City Clerk APPROVED AS TO FORM BY: Shelley M. Kerslake, City Attorney Sim Haggerton, Mayor Filed with the City Clerk: Passed by the City Council: Published: Effective Date: Ordinance Number: W: Word ProcessingkOrdinances\Speed limit reduced on TIB strike -thru 7 -24 -12 BG:bjs Page 2 of 2 14 TRANSPORTATION COMMITTEE Meeting Minutes August 0, 2012 5:151). n7. C'onlerenee Roon7 No. I Citv of Tukwila Transportation Committee PRESENT Councihmmbers: Allan Ekberg, Chair, Kathy Hougardy and De' Sean Quinn Staff: Bob Giberson, Frank Iriarte, Robin Tischmak, Gail Labanara and Kimberly Mat j Guests: Sharon Mann CALL TO ORDER: The meeting ryas called to order at 5:19 p.m L PRESENTATIONS No presentations. II. BUSINESS AGENDA A. TUklylla International Boulevard Sneed Studs Ordinance Staff is seeking approval of an ordinance that syill losyer the speed limit on Tukwila International Boulevard from 40 mph to 35 mph from South 139 Street to South 152"" Street. After the completion of the Tukwila International Boulevard roadsyay improvements, a traffic engineering study vvas conducted to assess speeds, traffic volume, and collision rates on the roadway. The results of the study suggest that the speed limit currently set at 40 mph should be reduced to 35 mph. Additionally, mid block crosswalks at the 14300 and 15100 blocks are proposed to be retrofitted in 2013, which should assist in the reduction of collision rates. Detailed data collection and results are included in the Committee agenda packet. Staff stated that once the speed limit signs change and have been in place for a year, the area will be assessed again to compare data and findings in order to make any other necessaiv adjustments. UNANIMOUS APPROVAL. FORWARD TO AUGUST 13 COW FOR DISCUSSION. B. Tukwila Urban Center Access (Klickitat) Proiect LID Final Assessment Study Staff is seeking Council approval to enter into a consultant agreement with Macaulay Associates for the final special benefit/proportionate assessment study for TUklylla Urban Center Access (Klickitat) Local Improvement District (LID) No. 33 in the amount of $142,800. Macaulav Associates conducted this project's LID preliminary assessment in 2009. The final assessment will result in a final report of findings relative to 278 properties in the LID and the special benefit to each parcel based on cost/benefit ratio results that is fair and proportional. UNANIMOUS APPROVAL. FORWARD TO AUGUST 13 COW FOR DISCUSSION. III. SCATBd There syere no items relating to SCATBd agenda items. IV. MISCELLANEOUS At the request of Committee Chair Ekberg, the Committee discussed the possibility of placing time- limit signs for parking in Riverton neighborhood near the neighborhood commercial center at the intersection of East Marginal Wav South/40 Aveue South and South 00 Street. After a brief discussion, the Committee felt that it yeas a fair request for signage in order to encourage short -term parking near businesses that offer short-term services. This item does not need to go to fill Council for consideration as placement of such parking signage is in the prevue of the City Engineer. Meeting act ournecl at .5:571).177. Next meeting: Monday, August 20, 2012 5:15 p.m. Conference Room 41 t Committee Chair Approval llmrites by K4�. Revrelred hr UL. 15