Brazoria County Drainage Analysis & Water Flow Map

Address
Overview

Where does rainwater drain in Brazoria County? This interactive map shows surface drainage patterns across Pearland, Lake Jackson, Angleton, and surrounding areas based on terrain shape - where gravity directs rainwater based on elevation and slope. For official flood risk information, see the FEMA flood zone layer on the Hazards tab.

Brazoria County sits at the terminus of the Brazos River watershed, with extremely flat terrain averaging just 25 feet above sea level. Heavy clay soils resist infiltration, forcing nearly all rainfall into surface drainage channels. The Brazos River, San Bernard River, and Chocolate Bayou are the primary drainage conduits to the Gulf of Mexico. Enter any address to see parcel-level surface drainage analysis and water flow direction based on terrain shape.

Interpretation

Select a location on the map or enter an address to see terrain analysis.

3D Terrain Visualization
Where does rainwater flow based on terrain shape? Blue areas show where water collects and drains downhill.
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4.0× Horizontal:Vertical
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