Clear Lake (169) (Wasco)

Reachcode: 17070306002028 | Area: 521.1 acres | Shoreline: 7.0 mi | View on Interactive Map

(From Atlas of Oregon Lakes, Johnson et al. 1985).  Clear Lake was a small natural lake on the southeast slope of Mt. Hood until it was increased in size in the 1950s to serve as a storage impoundment for irrigation in Wasco County. The 44-foot high earthfill dam that impounds the headwaters of Clear Creek is called Wasco Dam and the lake itself is frequently referred to as Wasco Reservoir. It is operated as a component of the Juniper Flat District Improvement Company. Clear Creek is a tributary of the White River, but much of the outflow from the reservoir is diverted into the Clear Creek Irrigation Ditch prior to joining the White River. The drainage basin, entirely within the Mt. Hood National Forest, supports a dense forest of fir and hemlock. 

Prior to enlargement, Clear Lake offered excellent fly-fishing for brook trout. Fishing is still good for brook trout and also rainbow trout. Trolling and bait fishing are common in addition to the use of flies early and late in the day. However, successful trout fishing is somewhat restricted by the seasonal draw-down to meet downstream water needs. Very low water levels occur in late summer and fall, the time of maximum irrigation needs. 

Although the maximum depth of Clear Lake is only about 22 feet (approximately 32 feet at full pool) the walls of the basin are steep and much of the rest of the bottom is relatively flat so that the mean depth is 15.6 feet. The shape of the reservoir is branched, characteristic of impounded water bodies. There is no significant growth of macrophytes in the reservoir. Stumps left from logging of the basin are visible in shallow water and are exposed when the water level is lowered in the fall. The water is transparent and the bottom can be seen at all depths. The mineral content of the water is low, as are alkalinity and conductivity. Nutrient concentrations are also low and there is relatively little growth of phytoplankton. Productivity is limited and the reservoir is oligotrophic.