The Federal Clean Water Act requires large and medium sized towns (Abilene meets the large criteria) across the United States to take steps to reduce polluted stormwater runoff. The law was applied in two phases. The first phase addressed large cities. The second phase, often referred to as "Phase II," requires medium and small cities, fast growing cities and those located near sensitive waters to take steps to reduce stormwater.
These laws require chosen cities to create a Stormwater Management Plan to meet the requirements in the City's permit.