Phillips Lake (Baker)

Reachcode: 17050203006928 | Area: 2244.6 acres | Shoreline: 20.2 mi | View on Interactive Map

(From Atlas of Oregon Lakes, Johnson et al. 1985). Phillips Lake in east-central Oregon is the primary component of the Upper Division of the Baker Project, a Bureau of Reclamation project that provides water for the irrigation of agricultural land in the Powder River Valley near the city of Baker. The Lower Division of the project, consisting of Thief Valley Dam and Reservoir, provides a supplemental water supply for about 7300 acres along the Powder River northeast of Baker. Water resource development in the Upper Division has been under study since about 1930, and the present development evolved from an earlier plan that contemplated a valley-wide irrigation district. The irrigated area now served by the Upper Division consists of 18,500 acres adjacent to and north of Baker, and includes some contiguous areas that had previously been dry-farmed. Project benefits also include flood control, fish and wildlife enhancement, and recreation. Construction of Upper Division facilities, including Mason Dam which impounds Phillips Lake, was begun in 1965 and completed in 1968. At full pool the lake is five miles long, covers 2435 acres, and has a capacity of 90,500 acre-feet. The lake was named for Fred Phillips, a prominent Baker resident and long-time advocate of the project.

The 144 square-mile drainage basin contributing to Phillips Lake is mostly within the Wallowa-Whitman National Forest and is covered with a coniferous forest. The Forest Service is charged with management of lands surrounding the lake and has established two campgrounds and two boat launching sites. A small campground is located adjacent to the dam and a very large one, Union Creek Campground, is on the north side of the lake. There are also two designated overflow camping areas at the west end of the lake. Facilities are all accessible from the Sumpter Valley Highway (Highway 220) which flanks the north side of the lake. An unpaved road along the south side of the lake is closed to vehicular traffic. Visitor use at Phillips Lake has been quite heavy since its completion. In addition to use by fishermen and campers, there is also swimming and water-skiing during the summer months. Fishing is particularly good near the dam, although success has frequently been hindered by the presence of rough fish. Recreational use of the lake has been greater than expected and there are definite signs of overuse by visitors. The indiscriminant use of land outside designated camping areas has caused serious damage including soil loss, soil compaction, vegetation destruction, litter and trash, wildlife harassment, and general unsanitary conditions. Most of the damage has been caused by vehicle use.

Upstream from the lake is a region of great historical and natural significance. Much of the Sumpter Valley consists of piles of rock dredged up during a period of intense hydraulic mining earlier in this century. The valley bottom was ruined by this final phase of gold extraction. However, due to some channeling, the area has become prime wildlife habitat, a nesting area for birds, and the year round home for small mammals; deer and elk also winter here. A few artificial snags have been installed on a meadow along the northwestern shore of the lake and serve as nesting sites for eagles and hawks. The Sumpter Wildlife Area is immediately upstream of the lake, a designated area of about 36,000 acres that extends about 11 miles to near the town of Sumpter. The conversion of the Sumpter Valley gold dredge site into a viable wildlife area offers a blueprint for the reclamation of land ravaged by the effects of mining.

The lake basin is characteristic of reservoirs, with the deepest point near the dam at the eastern end, and becoming progressively shallower toward the upstream end of the reservoir; there are numerous small embayments where smaller tributary streams enter. Macrophytes grow in these shallow enbayments, but are not abundant. Also characteristic of reservoirs, the banks are not yet stabilized and turbidity plumes develop from bank erosion when winds create surface waves. The mineral content of the water is moderate; calcium and sulfate are somewhat above average for eastern Oregon reservoirs. The pH is frequently above 8 during the summer as a result of the growth of phytoplankton. In 1970, the most common species of phytoplankton was a diatom, Melosira granulata, which is common in eutrophic lakes (McHugh 1972). A phytoplankton sample collected on 8/16/82 was dominated by Aphanizomenon (a blue-green alga), but the total phytoplankton density was unusually low. This alga was not present in a sample collected three weeks earlier, and may have been increasing on the 8/16/82 sample date. Gloeotrichia, which is a blue-green alga that forms large colonies, was visible but was not abundant in the lake. Phosphorus and chlorophyl concentrations are moderate to high, and water transparency is low to moderate. Surface temperatures can become fairly warm in mid to late summer, but the reservoir remains cool below 100 feet (30 meters). There is some tendency for oxygen depletion in deeper water. Overall, Phillips Lake is mesotrophic in character.


The list below includes results of zebra and quagga mussels surveys conducted by the Center for Lakes and Reservoirs and other agencies. The results "non-detect" and "results pending" indicate that surveys for zebra and quagga mussels were conducted, but none were detected or results are pending. For more details on zebra and quagga mussel monitoring, please visit the Online Mussel Monitoring Map.

Date Status/Species Source
Aug. 1, 2009 non detect Portland State University
No plant data available.
0/0