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Exhibit A Diking District 5 Dike Repairs and Improvements Project Phase 1 - Evaluation of Alternatives Otak Project No. 32758 Proposal for Professional Services July 2016 Background Information This project is located northeast of the City of Everett(the City),within the Snohomish River Estuary on the northern side of Smith Island. Smith Island is located between the Snohomish River to the west and Union Slough to the east. There is a system of dikes around Smith Island that protect the island from much of the flooding that can occur due to high tides and river discharges. Much of the dike system on Smith Island is currently within Diking District 5 (DD5).Portions of the dike system along Union Slough within the district,and portions within the city but outside the district boundary are in need of repair in accordance with the Army Corps of Engineers'2015 inspection,due to erosion and scour along the slope of the dike facing the slough.These portions of the dike system outside of the district boundaries also provide protection to the District,thus the District considers them vital to protect the district and will make the repairs. The dike repairs can potentially span approximately 5,200 feet from the tie in of the Snohomish County set back dike to State Route 529.Along this span DD5 noted that there are three common types of erosion that have caused significant damage to the dike- erosion of the last foot to two feet of the dike toe above the Ordinary High Water Mark (OHWM),erosion of the dike toe to a vertical where re-establishing the toe would require extending below the OHWM,and slumping of the riverward top of the dike where erosion below the OHWM has destabilized the dike toe. While this project will be repairing the riverward toe and slope of the dike,DD5 is considering establishing the dike crown at an elevation of 15 feet and widening the dike where necessary to remain drivable (15 feet wide).The project will provide for scour protection along the riverward slope. Part of the consulting effort will be to determine the permitting and approvals for the implementation of these repairs and if there are different permit requirements for any element. Therefore,this initial work scope will evaluate the engineering and permitting requirements for the repairs,and if the permitting requirements for the repairs appear similar to what may be necessary for the dike improvements,we will add the analysis of the improvements as a future supplement. This work is expected to be completed in two phases.The first phase will include survey and mapping,geotechnical investigation and analyses,environmental studies,and engineering analyses to provide DD5 with a comparison of alternatives for the repairs,and improvements (if requested by DD5 Dike Repairs and Improvements Project 1 K\project\32700\32758\Contract\Scope for Phase 1—DD5 dike repairs final 7-22.docx