Coastal GIS based watershed pollution assessment tool

What is it?
"The Cooperative Extension MANAGE (Method for Assessment, Nutrient Loading And Geographic Evaluation) method is used for risk assessment. It is a Geographic Information System (GIS)-based tool that informs decisions about risks associated with land use. The method uses a series of environmental indicators to rank risks to surface- and groundwater resources. The indicators can be varied based upon the objectives of the user and the characteristics of the site. The results of the model are presented in a variety of formats, including maps and data tables. The focus of the method is on identifying high risk situations that can lead to impaired water quality, allowing for the identification of appropriate management options.

How Does It Work?
Readily-available Geographic Information System (GIS) data including streams and ponds, pollution point sources, and soils, are processed using an ArcView tool. The output of this step are summary data about the study area. Summary data might include percentages of land use types on specific soils and percentage of land use types in riparian areas.

This summary data is then input into an Excel spreadsheet model which calculates values for risk indicators such as stormwater runoff, nutrient loading estimates, and impervious surface."