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EXHIBIT A Everett Project Scope Project: Lexington/Wetmore Storm Drainage Feasibility Report Date: Thursday,March 31, 2022 Project Location: City of Everett—1-5 and Lowell Street Vicinity Topic:: Feasibility Evaluation Background The City of Everett has experienced overloading of existing stormwater conveyance systems in the stormwater basin in the vicinity of Lexington and Wetmore Streets. The conveyance system has been determined to be under capacity resulting in localized flooding during large storm events. The City has developed a concept to replace some undersized sections of the storm drainage conveyance system and construct new pipelines to carry stormwater to the east toward the Snohomish River. The storm drainage basins are shaded blue in the attached figure labeled Attachment 5A. The replacement and new pipelines are also indicated in the figure. In addition,the City has identified a combined sewer basin shaded orange in the figure that has already been partially separated; however,the separated flows are merged back into the combined sewer system at lower points within the basin. There is an opportunity to intercept the storm water from the combined sewer basin and convey this to the proposed stormwater piping and thereby reduce the hydraulic loading on the combined sewer system. The new stormwater flows would need to be treated and discharged to the Snohomish River. The two options that have been identified include conveying the flow into a regional water quality treatment wetland (aka Constructed Wetland)that is hydraulically connected to the river,for ultimate discharge to the river, or constructing a storm water treatment facility with engineered structures (such as filter cartridges)that will provide enhanced water quality treatment and then discharging directly into the river through a new outfall to the Snohomish River. These two concepts are illustrated in the attached figure labeled Attachment 5B.A hybrid option could involve enhanced water quality treatment and flow control followed by discharge into an existing wetland,with eventual discharge to the river. The City received grant funding from the Department of Ecology for another project that will no longer proceed. The City has requested that the grant funds from the other project be reallocated by Ecology to the project described above. Ecology has indicated a willingness to reallocate the grant funds provided a feasibility study is submitted demonstrating the viability of this new project before June 2022 when the grant expires. Pre-design/Feasibility Goal: Provide the City with a pre-design or feasibility evaluation,of sufficient detail on the project to determine viability of project. This study will be submitted to the Department of Ecology to decide if they want to extend the g rant/contract and re-allocate the original construction funds for this projects design work. 929 108th Avenue NE,Suite 1300,Bellevue,WA 98004 T 425.450.6200 hdrinc.com