Overlake Regional Facilities
The City is currently working on a Basin Plan for Ecology approval that will document the design of various regional stormwater facilities proposed within the Overlake neighborhood.
2010. Following the Overlake Neighborhood Plan update, the City adopted an Implementation Plan to guide the City in its objective to improve management of stormwater within the Overlake neighborhood. This plan focused on the commercial and employment areas of the neighborhood that are zoned for the highest density of development. The plan was developed to implement policies of the Overlake Neighborhood Plan. The proposed stormwater facilities and some new streets were further defined by the Overlake Village Street Design Guidelines, adopted by City Council in April 2011.
2012-2013. Overlake Village LID Retrofit. The first investment the City made in improving stormwater in this neighborhood is construction of rain gardens in existing streets where there was more pavement than needed for transportation demands. Removed pavement was replaced with attractive and functional rain gardens that provide stormwater treatment and flow control to protect creeks downstream from urban runoff. These improvements made the area more pedestrian friendly and give a peek into the future of the Overlake Village. Construction in 2012 was hampered by unmarked utility conflicts that led to project delay. The project will be completed during the summer of 2014. These interim rain gardens may be removed as redevelopment occurs and streets are widened, in the future.
2013-2015. Overlake Village South Detention Vault. The first large stormwater facility will be a regional detention facility that will detain stormwater that has been treated locally within public rights-of-way and private development areas. Once surrounding property develops in the future, park facilities will be constructed on top of the stormwater vault. In the meantime, parking use will continue by the owner of the property. The development of this park would occur in the future with other neighborhood redevelopment. Utility relocations to accommodate the new vault were completed in 2013 and the vault is scheduled to begin construction in early 2014. The vault will be operational in 2014 with site restoration completed in 2015.
2016-2018. Overlake Village Station Infiltration Vault. The second large stormwater facility proposed will be a regional infiltration facility that will provide retention of stormwater and treatment by infiltrating the stormwater into the ground. This facility is proposed for construction in coordination with the Sound Transit East Link Light Rail, proposed to open in 2023. The City is working on design of this facility in cooperation with Sound Transit so it can be fully integrated into the light rail station project. It is proposed to be built by Sound Transit's Design/Build Contractor.
2025. Overlake Village Central Infiltration Vault. The third and final large stormwater facility will occur as redevelopment occurs in the future. This large facility will complete the retrofit of the Overlake basin to current stormwater runoff treatment and flow control standards. A two acre park will be constructed on top of the stormwater vault, surrounded by new streets, (NE 26th Street, NE 27th Street, 151st Ave NE, and 152nd Ave NE). It is expected that private development will be triggered by the opening of the new light rail station and that this facility will be constructed in the mid to late 2020s.
2030. The urban pathway connecting the three large stormwater sites is intended to be developed within dedicated easements adjacent to City rights-of-way, and would be designed to include low impact development (LID) components. As public and private development move forward, these infiltrating, smaller-scale stormwater facilities will allow more efficient use of the large regional stormwater facilities and will help create much improved flow conditions in the streams where this stormwater flows.