The Virginia Assessment and Scenario Tool (VAST) allows users to rapidly develop
scenarios with varying best management practices.
Output includes nitrogen, phosphorus, and sediment loads from all sectors and sources,
acres of each BMP, and costs for the scenario for any area in the Chesapeake Bay
Watershed. These loads are consistent with the Chesapeake Bay Program’s Watershed
Model. VAST also provides inputs to the Chesapeake Bay Program computer models.
Users can compare among scenarios to select the practices that reduce the most pollution,
are most cost-effective, and target these practices to the highest impact areas.
Scenarios can be used for TMDL Watershed Implementation Plans, Milestones, or for
local planning purposes.