Pilchuck River Dam (Snohomish Water System) [All information extracted from the Aug 2011 “City of Snohomish Comprehensive Water System Plan”] Existing Water System History The Snohomish River valley’s flat land and favorable soils began drawing settlers from Seattle in the late 1850s for agricultural use. A railway was developed through the valley and into the community of Snohomish in the 1880s and brought with it the lumber industry and the need for the community’s first water system, which was originally constructed entirely of wood stave pipe. This water system was developed in 1884 and involved the pumping of water from a stream tributary to the Snohomish River located north of First Street. A water company was formed in 1887 that used the community’s topography to provide water via gravity from Blackman’s Lake. In 1891, additional water was provided to the City via a pumping station and storage reservoir situated on the Pilchuck River to support the City’s numerous lumber mills. Shortly after the City of Snohomish was incorporated in 1890, major fires disrupted business throughout the City, with 35 businesses destroyed in the 1911 fire. Over the next decade, the City was rebuilt and in 1920, reached a population of over 3,000 people, which remained relatively constant for the next 40 years. In 1912, the existing water supply facilities were replaced with a dam on the Pilchuck River, a 12- inch wood stave transmission main and an open ground-level reservoir, which have all been either abandoned or replaced. An additional reservoir was constructed in 1925 at the same site as the original reservoir. This reservoir, Reservoir No. 1, has an existing capacity of 1.0 million gallons (MG). In the late 1920s and early 1930s the City replaced the wood stave pipe distribution system with cast iron pipe. At this time a diversion dam, which is still in operation today, was constructed on the Pilchuck River in nearly the same location as the original dam. Since the construction of the diversion dam was completed in 1934, a fish ladder and a continuous flow fingerling bypass were installed to keep the intake screen free of fingerlings. A 5.0 MG reservoir, Reservoir No. 2, was constructed in 1953 at the same site as Reservoir No. 1 and the original reservoir. Reservoirs No. 1 and 2 remain in operation today and provide the only storage for the City’s 218 Zone. In the early 1950s, the City of Everett constructed Transmission Line No. 5 near the northern boundary of the Snohomish City limits. Shortly after construction of this transmission main, the City installed an emergency connection on Terrace Avenue. Although originally intended for emergency use only, the City eventually began using this connection for continuous water service to the northern portion of the City. This led to increased development north of 13 th Street and created the need for additional transmission main connections, four of which are in service today, to serve the City’s water service customers. Future Water Demands and Water Supply Overall water demand within the City’s system is expected to increase by up to 11 percent within the next 6 years, and by up to 52 percent within the next 20 years, depending on the amount of future water use reductions from the City’s Water Use Efficiency Program. The City is considering plans , OCR Text: Pilchuck River Dam (Snohomish Water System) [All information extracted from the Aug 2011 “City of Snohomish Comprehensive Water System Plan”] Existing Water System History The Snohomish River valley’s flat land and favorable soils began drawing settlers from Seattle in the late 1850s for agricultural use. A railway was developed through the valley and into the community of Snohomish in the 1880s and brought with it the lumber industry and the need for the community’s first water system, which was originally constructed entirely of wood stave pipe. This water system was developed in 1884 and involved the pumping of water from a stream tributary to the Snohomish River located north of First Street. A water company was formed in 1887 that used the community’s topography to provide water via gravity from Blackman’s Lake. In 1891, additional water was provided to the City via a pumping station and storage reservoir situated on the Pilchuck River to support the City’s numerous lumber mills. Shortly after the City of Snohomish was incorporated in 1890, major fires disrupted business throughout the City, with 35 businesses destroyed in the 1911 fire. Over the next decade, the City was rebuilt and in 1920, reached a population of over 3,000 people, which remained relatively constant for the next 40 years. In 1912, the existing water supply facilities were replaced with a dam on the Pilchuck River, a 12- inch wood stave transmission main and an open ground-level reservoir, which have all been either abandoned or replaced. An additional reservoir was constructed in 1925 at the same site as the original reservoir. This reservoir, Reservoir No. 1, has an existing capacity of 1.0 million gallons (MG). In the late 1920s and early 1930s the City replaced the wood stave pipe distribution system with cast iron pipe. At this time a diversion dam, which is still in operation today, was constructed on the Pilchuck River in nearly the same location as the original dam. Since the construction of the diversion dam was completed in 1934, a fish ladder and a continuous flow fingerling bypass were installed to keep the intake screen free of fingerlings. A 5.0 MG reservoir, Reservoir No. 2, was constructed in 1953 at the same site as Reservoir No. 1 and the original reservoir. Reservoirs No. 1 and 2 remain in operation today and provide the only storage for the City’s 218 Zone. In the early 1950s, the City of Everett constructed Transmission Line No. 5 near the northern boundary of the Snohomish City limits. Shortly after construction of this transmission main, the City installed an emergency connection on Terrace Avenue. Although originally intended for emergency use only, the City eventually began using this connection for continuous water service to the northern portion of the City. This led to increased development north of 13 th Street and created the need for additional transmission main connections, four of which are in service today, to serve the City’s water service customers. Future Water Demands and Water Supply Overall water demand within the City’s system is expected to increase by up to 11 percent within the next 6 years, and by up to 52 percent within the next 20 years, depending on the amount of future water use reductions from the City’s Water Use Efficiency Program. The City is considering plans , Granite Falls Historical Society,Documents (articles, clippings, letters, papers),Mapping Articles,P-T,Pilchuck_Dam.pdf,Pilchuck_Dam.pdf Page 1, Pilchuck_Dam.pdf Page 1