Characterize the Watershed - Identify Causes and Sources That Need to Be Controlled

Together with the input from stakeholders and your local knowledge of the watershed, analyzing the data should lead to an understanding of where and when problems occur in the watershed and what could be causing the problems. Ideally the data analysis phase will progress in such a manner that each analysis leads to a greater understanding of the problems, causes, and sources (i.e. each analysis identifies another piece of the puzzle).

You should now be able to identify the key sources you will quantify in the next step of the watershed planning process. You should also develop a brief report summarizing your data analyses and their results and describing the watershed sources, including their location, associated pollutants, timing, and impact on the waterbody.

Some sources will be expected to have a greater impact on watershed quality than others and might require a more detailed analysis. For example, if runoff from developed areas is expected to be the primary cause of elevated metals in watershed streams, it might not be necessary to evaluate subcategories of agricultural or other undeveloped lands in the loading analysis. You can likely group those land uses or sources together and focus on the developed areas, possibly even breaking them into more detailed categories (e.g., suburban, commercial, etc.).

EPA Envirofacts - This website provides access to several EPA databases to provide you with information about environmental activities that may affect air, water, and land anywhere in the United States.