Total nitrogen and total phosphorus concentrations from surface water samples collected by the Citizen-Led Environmental Observatory (CLEO) from multiple nearshore sites in Lake Lillinonah, Connecticut, USA, 2011-current

Included in this data package are water quality data from the Citizen-Led Environmental Observatory (CLEO), a volunteer water quality monitoring program run by Friends of the Lake (FOTL, friendsofthelake.org) and Fairfield University at Lake Lillinonah, Connecticut, USA. The program has been operational since 2008 (data available 2011-current). Trained volunteer monitors collect surface water samples from multiple nearshore sites twice a month from Memorial Day through Labor Day. These samples are analyzed for total nitrogen and total phosphorus concentrations. Water samples are also analyzed for levels of the toxin microcystin. Additionally, CLEO volunteers collect data on water temperature, Secchi disk depth, water color, presence of floating woody debris, recreation potential, trash, particle type and surface scum every 1-3 days during the same period. These additional data are available in EDI packages EDI567 (general water quality) and EDI569 (toxins).