Low-flow characteristics of streams on the Kitsap Peninsula and selected adjacent islands, Washington

Abstract

Streams in the study area drain relatively small basins; only three streams have drainage areas greater than 20.0 square miles (51.8 square kilometers), and only nine other streams have drainage areas greater than 10.0 square miles (25.9 square kilometers). Mean annual precipitation during the period 1931-60 ranged from about 25 inches (640 millimeters) near Hansville to about 70 inches (1,780 millimeter^) near Tahuya; it may be greater in the Green and Gold Mountain area. July is normally the month of least precipitation, and the lowest streamflows generally occur in September. Low-flow frequency data are tabulated for 90 streamflow sites in the study area; also listed are data for 56 additional sites which have insufficient measurements for frequency analysis but which have been observed having no flow at least once during the low-flow period. At the time of collection of field data, no effort was made to evaluate the effects of man on the streams' low flows. The eight streamflow gaging stations used in the low-flow analysis were all established after 1945, but all have had 10 or more years of record since then, and all were operated through the period of deficient rainfall, 1962-67. Low flows varied considerably during the periods of record of the stations. For example, variations in the 7-day low flows of Gold Creek near Bremerton ranged from 0.24 cubic foot per second (0.0068 cubic meter per second) in 1967 (at end of 6-year period of deficient rainfall) to 0.77 cubic foot per second (0.022 cubic meter per second) in 1948, a year of above average rainfall. Low-flow-frequency curves plotted from records of streamflow at the eight long-term gaging stations were used to determine data for low-flow durations of 7, 30, 60, 90, and 183 days. Regression techniques then were used to estimate low flows with frequencies up to 20 years for stations with less than 10 years of record and for miscellaneous sites where discharge measurements have been made.

Water resources of the Gig Harbor Peninsula and adjacent areas, Washington

“…Low flows were calculated for intervals of 7, 30, and 90 consecutive days at 1-, 10-, and 50-percent probabilities of not being exceeded in any year (table 2). Low flows calculated in an earlier report (Cummans, 1977) show excellent agreement (+2 percent) with the calculations in this report for Huge Creek (site 25), but the previous low-flow calculations for sites 15, 17, 21, and 23 were substantially less than the calculations in this report (7 to 58 percent less). These low-flow calculations have been revised upward because more data are now available.…”

“…These low-flow calculations have been revised upward because more data are now available. Most of these sites had been measured only five or six times when the earlier calculations were made (Cummans, 1977). The present calculations include 12 additional measurements at each site.…”

Hydrogeologic framework of the Puget Sound aquifer system, Washington and British Columbia

“…Starting with the reports of Hidaka (1973) for the Puget Sound region and Nassar (1973) for the Pacific Slope basins, the low-flow characteristics of streams in the Puget Sound Lowland were systematically analyzed. The later reports of Cummans (1977), LaFrance (1978), andWilliams (1987) documented the low-flow characteristics for much of the remainder of the Puget Sound Lowland.…”

Analysis of low flows and selected methods for estimating low-flow characteristics at partial-record and ungaged stream sites in western Washington

“…Hidaka (1973) computed low-flow indices for streams in the Puget Sound region from flowfrequency curves and determined that low-flow characteristics were different for mountain and lowland streams largely due to snowmelt contributions to mountain streams, and characteristics for lowland streams varied according to basin elevation. Other researchers (Collings and Hidaka, 1974;Cummans, 1977;Haushild and LaFrance, 1977;others, 1985a, 1985b;Curran and Olsen, 2009) calculated low-flow frequency statistics for streams in selected basins or subregions of western Washington. Sinclair and Pitz (1999) computed base-flow characteristics for all USGS gaging stations in Washington and characterized the degree of streamflow alteration and the dependence of low flows on snowmelt processes.…”