Size: 30.5 Acres
Maximum Depth: 13 Feet
Average Depth: 6.85 Feet
Maximum Volume: 68,100,000 Gallons
Lake Maintenance
During the warm summer months, a common and nearly annual source of concern when the water levels recede is algae blooms. Algae are essential ingredients in a balanced aquatic environment. However, following periods of hot weather, conditions which trigger episodes of rapid algae growth followed by its rapid die-off can occur. The cycle is a natural one that occurs during the hot summer months, and can unfortunately result in unpleasant odors occurring from the decomposing algae. Through the years, there have been various efforts undertaken to help maintain the Lake’s water quality and minimize algae blooms.
In 1962, prior to incorporation of Atascadero as a City, San Luis Obispo County had the bottom of the lake scraped to further enlarge and deepen the basin, and the soil from that sediment removal project was then used to create the island.
The City of Atascadero has a nearby water well which has been used in the past to help supplement water levels in the Lake, but when there’s little rainfall, the shallow well naturally runs low and therefore is of not much use during these periods. The City has also implemented the use of a diverter in Atascadero Creek to send some of the creek’s water flow into the Lake, to assist in keeping the water levels in the Lake at optimal levels. Again, during periods of drought or even just when winter rainfall is low, Atascadero Creek doesn’t run as high and therefore water cannot be diverted from the creek into the lake.
The City of Atascadero has also implemented various aeration efforts through the years, including removing sediment from the lakebed, aeration devices and fountains and an on-going repairs and upgrades to the creek-to-the lake supply pipeline.
To further assist in maintaining an optimum water level and quality, in recent years the Friends of Atascadero Lake (FOAL), a local non-profit group which was formed to help keep the Lake beautiful and inviting, drilled a new well on a nearby property and installed a supplemental pipeline to the Lake, which provides fresh water during the summer months. In 2017, FOAL commissioned an aeration system to promote circulation and oxygenation to the Lake.
Even though algae growth cannot be completely eliminated, the City has employed and continues to explore various methods to address algae growth, and continues our work and partnership with Friends of Atascadero Lake and other members of the community. Addressing water quality and algae blooms in Atascadero Lake has always been and always will be a very important and ongoing effort.
Although the Lake is owned by the City of Atascadero, it is important for the public to know that all projects that are planned to be taken in or near Atascadero Lake are governed and overseen by numerous State and Local Regulatory Agencies (such as Regional and State Water Quality Control Boards, the California Department of Fish and Wildlife, and more.) The regulatory process must be followed and the appropriate permits and approvals must be received from one or more of these entities, before the City of Atascadero can undertake any actions which affect the Lake or its environs.