Greens Bayou

Greens Bayou

Last Modified: 06/23/2020 10:09 PM


Watershed Overview

Drainage Area Watershed Population Open Stream Miles Primary Streams
212 Sq. Miles 528,720 308 Miles Garners Bayou
Greens Bayou
Halls Bayou
Reinhardt Bayou

The Greens Bayou watershed is located in north Harris County and encompasses portions of the cities of Houston and Humble. The upper reach of Greens Bayou flows in an eastward direction and the lower reach flows southward into the Houston Ship Channel. The watershed covers about 212 square miles and includes four primary streams: Greens Bayou, Halls Bayou, Garners Bayou, and Reinhardt Bayou. 

There are about 308 miles of open streams, including the primary streams and tributary channels. Based on the 2010 U.S. Census, the estimated population of the Greens Bayou watershed is 528,720.  

Flooding of homes and businesses along Greens Bayou and its tributaries has occurred numerous times in the last two decades, with recent devastating flood levels throughout the watershed brought on by Tropical Storm Allison in 2001. Significant floodplains and high-density development have combined to cause high damages during frequent flood events. Additionally, storm surges can influence flooding levels along the lower 10 miles of the watershed.

Land Use

Most of the watershed is highly developed. Some large areas between U.S. 59 and I-10 remain undeveloped. Construction of new residential and commercial developments is expected to continue in the northern and western regions of the watershed.


The District is implementing the first wetlands mitigation bank in Harris County, which is located near the confluence of Greens and Garners Bayou. The mitigation bank provides compensating wetlands credits for projects that cannot avoid disturbing wetlands and qualify for credits. The wetlands bank and reaches of the bayou that pass through dense woodlands are highly sensitive and support diverse wildlife habitats. Downstream of I-10, the channel flowline is below mean sea level and this reach of the bayou is tidally influenced.

Projects In Greens Bayou Watershed

The Harris County Flood Control District has a significant number of flood damage reduction projects occurring all over Harris County as part of its on-going Capital Improvement Program (CIP), Operations and Maintenance, and the 2018 Bond Program. Click on the red and orange highlighted areas to learn about projects' details. See also the menu on the left of this page for additional project information. 

• Maintenance Projects   
• Capital Projects

How Water Flows In The Greens Bayou Watershed