The Washington D.C. area, like many cities, is covered with impermeable surfaces. With millions of cars on the roads every year, runoff is a major problem for the Potomac and the Anacostia rivers, which both empty into the Chesapeake Bay. Large buildings, constant construction, and an extensive highway system contribute to and expedite runoff. We will examine the amount of change in impermeable surfaces throughout the years and the effect runoff has on these two rivers. We also want to look at the permeable surfaces and see if change has increased or decreased the amount of runoff entering these two rivers. We hope to use data from USGS, PRISM, local DC data, and Chesapeake Bay Foundation. We will use ArcMap 10.1. This project addresses real problems that the District of Columbia faces every year. More importantly this project will help determine how much of an impact D.C. runoff has on the Chesapeake Bay.