Armand Bayou

Armand Bayou

Watershed Overview

Drainage Area Watershed Population Open Stream Miles Primary Streams
160 Sq. Miles 132,953 (2020 Census Data) 86 Miles Armand Bayou
Horsepen Bayou
Big Island Slough
Willowspring Creek
Spring Gully

The Armand Bayou watershed is located in southeast Harris County and encompasses portions of the cities of Houston, Pasadena, Deer Park, La Porte, and Taylor Lake Village. Armand Bayou flows in a southward direction from its headwaters near Deer Park to its mouth at Clear Lake. The watershed covers about 59 square miles and includes five primary streams: Armand Bayou, Horsepen Bayou, Big Island Slough, Willowspring Creek, and Spring Gully. There are about 89 miles of open streams within the watershed, including the primary streams and tributary channels. Based on the 2010 U.S. Census, the estimated population of the Armand Bayou watershed is 127,350.

Regional planning is important on Armand Bayou due to past historical flooding and future development, which is expected for this area. Sizable floodplains exist in areas along the main channel and in Pasadena, Deer Park, and La Porte. The watershed is also vulnerable to storm surges from hurricanes or tropical storms. Structural flooding has occurred several times in the past.

Land Use

Development is heavy in the upper and southwestern regions, while the mid to lower regions are sparsely developed. Several parks and a nature preserve are located along the lower third of the channel. Due to the close proximity to Johnson Space Center, Houston Ship Channel, and the Clear Lake area, urbanization is expected to rapidly continue in the near future.


The watershed hosts the 2,000-acre Armand Bayou Park and Nature Center at its mouth. An ongoing study is investigating the possibilities of creating habitat along the upper two-thirds of the channel and of linking regional detention sites and parks in the watershed in order to establish recreational and habitat corridors.

Projects In Armand 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 the Project ID on the Map to learn about projects’ details. Some early-stage projects are not highlighted on the map. The map will be updated when projects advance or when more information becomes available.

Summary of Armand Bayou Watershed Plan

Revised March 9, 2021

How Water Flows In the Armand Bayou Watershed