The Brazos River Forms the County's Eastern Edge
Washington County sits in the Blackland Prairies. The Brazos River forms its eastern boundary, and Yegua Creek marks the north. The county covers 611 square miles with a humid subtropical climate. Average annual rainfall is about 40 inches.
The Brazos can flood after heavy rain. If you are buying land near the river or its bottomlands, check the FEMA flood map for that parcel before closing. The FEMA Flood Map Service Center at msc.fema.gov lets you look up any address.
Content last revised 2026-07-11