Miami Conservancy District
Flood Protection Preserve Our Water Recreation About MCD Resources and Publications Contact Us
Water in the Great
Miami River Watershed
Groundwater Programs
Surface Water Programs
Water Data
Citizen Involvement
On the Water Front
Value of Water
What is a watershed?
A watershed is the land area that drains into a body of water.

Water will flow through forests and fields on its downhill journey to the nearest body of water: Be it a tiny stream, bubbling brook or ditch. It will also flow over lawns, driveways and roads. All of this land is part of the watershed. Eventually, the water ends up in a river, lake or ocean at the lowest point of the watershed.

Everyone is part of a watershed. Even if we don’t live near a body of water, we live in its watershed, and our actions on that land affect water quality far downstream.

Watersheds provide critical natural services that sustain or enrich our daily lives: They supply our drinking water, as well as provide important habitat for plants and animals, areas of natural beauty and water bodies for recreation and relaxation. Small streams are an important element of our local geography, and provide a strong sense of place to a community. Watersheds also include groundwater resources. Watershed management is a holistic approach to water quality issues. It recognizes and demonstrates the interconnectedness of land and water, surface water and groundwater, tiny streams and great oceans. 

The next time it rains, watch the water run off your roof, your driveway and down the street.  Everywhere you go, water is on its way to the nearest stream, lake or wetland. Some of it soaks into the soil to become groundwater and, over time, can replenish streams, lakes and aquifers. Some runs over land. When you add up all the land that catches water and drains it into the same waterway, you have a watershed. Parts of 15 counties in southwest Ohio drain to the Great Miami River and make up its watershed. The Great Miami, in turn, drains into the Ohio River and is part of the Ohio River Watershed.