Watersheds are areas of land that drain to a common river, stream or lake.

The size of the drainage area can range from several acres to several thousand square miles.

Therefore, all water, sediment and nonpoint source pollutants will drain to a common outlet after a rainfall. Pollutants will travel through a watershed to the nearest water body in a common way — through erosion and stormwater runoff.

Butler County now has three watershed organizations: the Connoquenessing Watershed Alliance, Bear Creek Watershed Association and Slippery Rock Watershed Coalition. These organizations have been busy working to complete projects to prevent and reduce water pollution.

The Watershed approach is based on four main principles:

• Identifying and targeting areas with the most severe nonpoint source pollution problems,

• Involving the affected public,

• Using the best methods and tools available,

• Implementing best management practices.

Nonpoint source pollution comes from many different sources. It is usually associated with rainfall runoff moving over and through the ground, carrying natural and man-made pollutants into lakes, streams, drinking water, etc.Some of these pollutants can take days, months or even years to break down.Major types of water pollutants include detergents and cleaning agents, septic waste, petroleum, lawn and garden waste, animal waste, pesticides, fertilizers and sediments.Since almost all nonpoint source pollution is directly related to the way we use the land, we are all contributing to the problem.A best management practice is a measure or combination of measures designed to control a problem.Such practices to deal with nonpoint source pollution include:• Structural methods, such as constructing and installing stormwater detention basins.• Nonstructural methods, including the use of vegetative buffers to reduce erosion.• Institutional methods, such as implementing and enforcing ordinances to prevent erosion and runoff.To reduce pollution, the different practices should be applied to the entire watershed as appropriate.<b><i>Ron Fodor is district manager of the Butler County Conservation District.</i></b>