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Critical Source Areas

Downloadable Documents & Helpful Links


Critical source areas are areas of the landscape that contribute disproportionately high levels of nonpoint source (NPS) pollution relative to other areas. When it comes to reducing NPS pollution, identifying and targeting CSAs can give you the biggest bang for your buck. VAAFM has collaborated with the Lake Champlain Basin Program and other partners to model phosphorus CSAs in the Missisquoi Bay watershed for use as a natural resource planning tool, and with the United States Department of Agriculture Natural Resources Conservation Service (NRCS) to implement conservation practices on confirmed phosphorus CSAs.

Map 1: Subwatershed in the Missisquoi Bay with the CSA model overlay

Map 2: Model Results (close up)