Back in 1936, just five years after Shoreline Water District was founded, we were ever so proud to construct our area’s first-ever, brand new 50,000 gallon elevated water reservoir located at 15th Avenue NE and NE 180th Street, with the goal of providing adequate water pressure to area residents.
As more residences and businesses came into the area and demand for service grew, a second 400,000 gallon reservoir was constructed in 1950, adjacent to the first reservoir.
Finally in 1976, we demolished the old 50,000 gallon elevated reservoir and built our largest reservoir yet—the North City Reservoir, able to hold up to 3.7 million gallons—located adjacent to the 400,000 gallon reservoir.
The Dual Purpose of Water Reservoirs
Many people are not aware that water reservoirs serve two purposes: to hold water in reserve, and to maintain proper water pressure within a given service area. In order to be able to utilize more of the North City Reservoir’s stored water, we built a Pump Station adjacent to the reservoir in 1994.
Our area’s water capacity and pressure remained adequate until 2007 (Washington State Department of Health identifies storage volume requirements based on both population and non-residential uses). During that year, we took a close look at the overall system to decide what was best for our growing community—constructing a fourth water reservoir, or making a connection to a different water source (the Cedar River Watershed) via our water supplier, Seattle Public Utilities (SPU). (To date all of our water has been sourced from the Tolt River via SPU.)
After careful systems analysis by our engineering consultants to explore every available option, we determined that a second water connection was the most cost effective solution for ratepayers, as it would eliminate the need for additional storage within our current service area. (Should the City of Shoreline or Lake Forest park choose to change development density in our area, a new needs analysis would be required).
We approached and received permission from SPU to establish this new connection to the Cedar River source. With that connection in place, we identified what parameters would be necessary to design a new Pump Station so that it could distribute the enhanced water pressure as effectively as possible.
Scope of the Projects at North City
We began by obtaining a lot line adjustment in order to better utilize the property, after which we removed the 400,000 gallon reservoir to make more space on the site for the new pump station.
The first project—design and construction of a new pump station—will provide connection from an alternate pressure zone, along with significantly enhanced efficiency that will enable us to pump water to almost the entire District service area. The District has been working closely with design engineer BHC Consultants; the project will go out to bid in approximately June or July of this year, with an estimated 14 months of construction.
The second project will entail internal and external improvements to the 3.7 million gallon storage tank, as well as a fresh coat of paint. Our consultant RH2 Engineers expects to have this project out to bid in March and be completed by mid Summer 2013. Passersby can expect to see scaffolding erected around the reservoir for almost the entire duration.
The third project will be to install 540 feet of new water main at the intersection of 15th Avenue NE and 24th Avenue NE, to improve water pressure in that area. Our engineers, BHC Consultants, expect to have the project designed and constructed by mid summer 2013, prior to the City of Shoreline starting their seal coat project in this same area.