Owasco Lake
Owasco Lake Management

Water Quality Issues
Recreational uses in Owasco Lake are affected by bacteriological contamination along the north shore and by excessive growth of aquatic vegetation and algae in other parts of the lake, particularly its southern end. The sources of bacteria include wildlife and waterfowl, agricultural runoff and to a lesser extent residential septic systems. Though nutrient (phosphorus) levels are generally low in much of the lake, higher levels in the southern end of the lake contribute to excessive aquatic vegetation. These impacts also threaten the water supply uses of the lake. Watershed Management Actions
DEC is working with local partners in the watershed to address these sources of pollution to the lake. Currently, DEC is addressing the amount of phosphorus entering the lake from the Owasco Inlet. DEC is also working with the Village of Groton to reduce the amount of phosphorus they are discharging to the Inlet from their municipal wastewater facility. Since entering into a Consent Order with DEC in 2006, Groton has significantly reduced the amount of phosphorous being discharged from its facility. In addition to requiring Groton to use new treatment technology to reduce phosphorus, DEC has set a more protective interim phosphorus discharge limit at the wastewater treatment facility. The only other significant point source discharge in the watershed is the Village of Moravia Sewage Treatment Plant which already uses a high level of treatment to reduce phosphorus discharge.
However, in order to fully address concerns about Owasco Lake water quality, a comprehensive approach to reduce nutrients and other pollutants from various contributors throughout the watershed is necessary. In addition to point source discharges, such as the wastewater treatment facilities, polluted runoff from developed areas, agricultural activities and other sources continue to result in high levels of phosphorus and bacteria in the lake, and harm the quality of the this important water body. Other important partners contributing to the comprehensive Owasco Lake watershed management effort include Owasco Watershed Lake Association, Cayuga County Health and Human Services, Cayuga County Planning and Economic Development, Cayuga County Water Quality Management Agency, the Finger Lakes Institute, the Upstate Freshwater Institute and Cayuga County Community College.
Published Water Quality Monitoring and Assessment Reports
Bioassessments - Biological Reports of specific rivers and streams.
- Owasco Lake Inlet, 2006 (links to PDF at NYS library)
- Owasco Lake Inlet, 2011 (PDF)
Facts About Owasco Lake
Owasco Lake is one of the six larger Finger Lakes in New York State. The lake itself is entirely within Cayuga County, while the watershed is located primarily in Cayuga County and Tompkins County, with a small portion located in Onondaga County. Owasco Lake is used for a variety of recreational activities. The lake also serves as a source of drinking water for the City of Auburn and the Town of Owasco and as such is classified as AA(T). The lake has been the focus of a number of monitoring studies, including a significant DEC monitoring effort Water Quality Study of the Finger Lakes (Callinan, DEC, 2002).