DFW Watershed Map

What Is a Watershed?

A watershed is an area of land where all rainfall and snowmelt drains to a common outlet — a creek, river, lake, or wetland. Watershed boundaries follow ridgelines and high points in the terrain. Everything on your side of that ridge drains to the same body of water as your neighbors, making watersheds a natural unit for understanding drainage and water quality.

HUC Levels Explained

The USGS organizes watersheds using Hydrologic Unit Codes (HUC). Each level nests inside the one above it, like a set of Russian dolls:

• HUC8 — Large river basins spanning thousands of square miles. In DFW, these include the Upper Trinity and Sabine basins.
• HUC10 — Sub-basins that break a HUC8 region into roughly 40–250 square mile sections. Useful for seeing how major creeks and tributaries divide the area.
• HUC12 — Local drainage areas of 10–40 square miles. This is the most detailed level and the best for understanding how water moves near your property.

Use the controls on the map to toggle between these levels and see how your property fits into the larger drainage network.

How Watersheds Affect Your Property

Understanding which watershed your property sits in tells you a lot about your drainage situation:

• Drainage direction — Water flows downhill toward the watershed outlet. If your property is at a low point, you receive runoff from uphill neighbors.
• Flood risk — Properties near watershed outlets or in low-lying areas within a basin face higher flood risk during heavy rain events.
• Stormwater management — New development upstream in your watershed increases impervious surface area, sending more runoff your way. French drains, dry wells, and proper grading can help manage that extra water.