Cross Lake, located on the Seneca River upstream of Baldwinsville, NY has been described as a “widening of the Seneca River”. The Seneca River flows through the extreme southern portion of the lake, with much of the river’s water “short-circuiting” a major portion of the lake, limiting the exchange of incoming river water with a large portion of the lake. The Seneca River constitutes approximately 98 percent of the inflow to the lake and has an average inflow rate of 86 m3/s. A bathymetric map of lake is shown below. The robotic buoy is located just inside the southern end of the 18 m contour. The lake is dimictic, alkaline with hard water. Cross Lake is hypereutrophic as a result of nutrient loading to upstream portions of the Seneca River from wastewater effluents and agricultural inputs. The export of high concentrations of phytoplankton from the lake to downstream portions of the river is a primary driver of dense populations of zebra mussels and severe impacts of this invader's metabolism on the Seneca River system. The river inflow is also rich in suspended solids, with approximately 70 percent inorganic solids. The lake thus acts as an effective settling pond, promoting the removal of some of this suspended material. The reduction of inorganic solids leaving the lake is believed to also contribute to the high zebra mussel density downstream of the lake by allowing the zebra mussels to more efficiently filter digestible organic solids (phytoplankton).
