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INFORMATIONAL MEMO <br />Page 4 <br /> <br /> <br />Z:\Council Agenda Items\DCD\Shoreline Update\SMP Council Info Memo 6-11-19.docx <br /> Additional Flexibility for Floodwalls <br />This update is happening alongside a discussion about flood protection measures in the Lower <br />Green River Corridor Flood Hazard Management Plan. There are multiple alternatives under <br />consideration including the question of whether future levees should be built to protect against <br />500 year rather than 100 year flood events. This could require levees to be between 3.5 and 5.5 <br />feet higher, which requires between 20 and 30 additional feet of width with a front and back <br />slope of at least 2.5:1 or adding 3.5 to 5.5 feet of height to a flood wall configuration without <br />the need for an additional 20 to 30 feet of width. <br /> <br />The current Flood Control District access road standard is 15’, not the 10’ built into our current <br />buffer calculation so the total width of the levee footprint could increase by up to 35 feet. <br />Allowing an alternative flood wall configuration to substitute for the back slope, especially <br />where site constraints exist, would reduce the width needed and lessen the impact on adjacent <br />property owners. Levees are so expensive to build and the consequences of a levee failure are <br />so significant that the need to allow site specific design solutions may be desirable to reach life <br />safety and economic goals. <br /> <br />Increased Height Incentives <br />The proposal is to provide increased building height incentives for property owners who <br />provide shoreline restoration or shoreline public access above that required by code. The PC <br />opted to increase the current shoreline foot height limit from 45 to 65 feet and allow another <br />15 foot increase on properties that restore shoreline buffers or build shoreline public access <br />amenities. These incentives would not allow heights greater than that permitted by the <br />underlying zoning district. <br /> <br />Non-Conforming Structures <br />In response to a public comments the PC recommends removing the cost limitation on <br />alterations or improvements to non-conforming structures within the shoreline buffer if the <br />buffer covers most of the parcel. If a non-conforming structure is demolished the footprint may <br />be incorporated into an adjacent parking lot.