Crump Lake (Lake)

Reachcode: 17120007341605 | Area: 8480.5 acres | Shoreline: 70.9 mi | View on Interactive Map

(From Atlas of Oregon Lakes, Johnson et al. 1985). Crump Lake is one of several lakes in a 40-mile chain in the Warner Valley of south-central Oregon. The valley is a large fault-block basin, and its floor is virtually a chain of marshes, shallow intermittent lakes, and drained meadows. From south to north, Pelican is the uppermost lake in the chain, followed by Crump and Hart and finishing at Bluejoint Lake. They vary greatly in size; all have been dry or practically dry at times, and the lower ones have been dry for several years, whereas during periods of high water, many of the lakes merge. Total drop in elevation in the lake-bed surface from Crump to Bluejoint Lake is only 13 feet. All these lakes are remnants of a large pluvial lake of about 500 square miles which covered the Warner Valley during the Pleistocene Epoch.

Crump Lake can be considered as transitional between a true closed-basin lake, such as Harney and Summer Lakes, and those that overflow every year. It overflows during many years, discharging into Hart Lake. Input to the lake is via direct precipitation, 10 to 15 inches per year, and runoff from Deep Creek and Twentymile Creek. There is very little contribution from groundwater. Crump Lake is one of the least disturbed of the Warner Valley Lakes, and has been evaluated for potential as a registered natural landmark. The lake and adjoining marshland support a rich spectrum of wildlife. Nesting waterfowl include white pelicans, Canada geese, and several species of ducks. Sandhill cranes and shore birds also inhabit the area. Surrounding vegetation is typical of the Great Basin desert, with sagebrush and juniper. Ownership of land on the valley floor is part state and part private.The valley sides are, for the most part, federal land administered by the Bureau of Land Management.

Like other shallow, alkali lakes in this area, Crump Lake has very high concentrations of phosphorus, major ions, and chlorophyl, and the water transparency is extremely limited by the presence of suspended organic particles. On 7/4/82 a transparency of only 1.3 feet (0.4 meters) was recorded. By all indications the ecological character of the lake is hypereutrophic. However, because Crump Lake does overflow in many years, it has a lower amount of solutes than the truly closed-basin lakes of the area.