Average total inflow to and outflow from the hydrologic system of the Swinomish Indian Reservation, Wash., is 24 cfs (cubic feet per second). Recharge to the ground-water reservoir is 8 cfs. The study area is underlain by three types of unconsolidated deposits: the uppermost unit is till, the intermediate unit is sand and gravel, and the lowermost unit is clay and silt. During 1975 the average rate of water use was 0.19 cfs. About 70 percent was pumped from the ground-water reservoir and the rest was imported. Dissolved-solids concentrations are 10-20 mg/L (milligrams per liter). In the zone of saltwater, differsion concentrations up to 1,570 mg/L were measured. Human interaction with the hydrologic system has had little effect on water quality. Ground-water quality is generally well within acceptable limits for most uses. If 20 percent of ground-water can be intercepted then a net rate of withdrawal of 1.6 cfs can be attained. Aquiculture development is possible on the two largest streams in the reservation in the form of incubation stations handling 600,000 eggs each. (Woodard-USGS)
Additional publication details
USGS Numbered Series
Water resources of the Swinomish Indian Reservation, Washington
Water-Resources Investigations Report
U.S. Geological Survey,
x, 83 p. :ill., maps (some fold. in pocket) ;27 cm.