Lookout Point Lake
- Lane County)
(From Atlas of Oregon Lakes, Johnson et al. 1985) Lookout Point Lake is a very large reservoir which extends for more than 10 miles along the Middle Fork of the Willamette River into the Calapooya Mountains southeast of Eugene. It is one of 13 multi-purpose water resource projects built and operated by the Corps of Engineers throughout the Willamette Valley. Lookout Point Lake and Dexter Lake, a re-regulating basin immediately downstream, were both completed in 1954 and have since prevented an estimated $200 million in damages from downstream flooding. Lookout Point Dam is also important for the generation of hydroelectric power; its powerhouse has three generating units and puts out 120,000 kilowatts of power. Normally the water level will be kept at a high level from May through August. From July through September it is gradually lowered as much as 12 feet below full pool to meet downstream water needs. After September it is lowered more rapidly to make space for winter flood waters. The lake receives heavy recreational use, especially for boating, but is poor for fishing. It is heavily infested with rough fish, suckers and squawfish. Several picnicking and boat launching facilities are located around the lake, some provided by Lane County, others by the state and the Willamette National Forest. The seasonal draw-down generally limits lake access from these sites.
The drainage basin is a forested region stretching to the crest of the Cascade Mountains, with steep and dissected topography. About three-quarters of the basin is managed by the Willamette National Forest, with significant private holdings upstream around Oakridge and around the lower half of the lake.
Lookout Point Lake is deep enough that it develops a pronounced thermal stratification in the summer. The intakes for power generation are below the surface and cooler hypolimnetic water is discharged downstream to Dexter Lake. Water chemistry is average for Cascade reservoirs. The pH of the water sometimes exceeds 8, presumably because of algal growth in the water. Oxygen levels remain near saturation at all depths. Chlorophyl and phosphorus concentrations and water transparency suggest that the lake is mesotrophic. Algal blooms have sometimes been observed in the lake and the species observed suggest a higher trophic state. Macrophytes are absent from the littoral areas, as is the case in most reservoirs that experience large fluctuations in water level.