At the beginning of every year, the District projects Lake Elsinore and Canyon Lake levels and these are presented in graphs posted on the website. The projections assume the worst case scenario of no rainfall over the entire year. The actual lake elevations are updated weekly on these graphs compared with projected readings. Updates are also made after any major storm events.
Inputs and outputs are considered based on the specific circumstances of the individual lakes. Lake Elsinore’s projected input is from the Island wells, and the output is evaporation. Canyon Lake’s projected outputs are the treatment plant production and evaporation. There is no projected input to Canyon Lake on the graph because it relies 100% on rainfall or natural runoff from the watershed. Rainfall data, as recorded, are also displayed on the graphs. Canyon Lake’s graph displays the contractual elevation and the dam overflow elevation as well as the treatment plant’s projected operational periods.
Lake Elsinore is supplied by inflow from the San Jacinto River and local watershed runoff. As the water elevation in Lake Elsinore increases, the water elevation in the Lake Outlet Channel rises until the Wasson Sill crest elevation of 1255-ft is reached, thus resulting in discharge of lake flows to Temescal Creek. During significant storm events, if the inflow to Lake Elsinore is greater than the Outlet Channel capacity, the surface water elevation of the lake will continue to rise until it reaches 1262-ft, thus resulting in conveyance of lake flows to the Back Basin storage area. The 100-year flood elevation of LakeElsinore is 1263.3-ft, whereas the lake levee top elevation is constructed at 1265-ft.