Projects & Studies
(UPDATE: On January 30, 2018, Harris County Commissioners Court authorized a $632,499 agreement with R.G. Miller Engineers for final design and construction phase engineering services for the linear stormwater detention project. Commissioners Court also awarded a $13.32 million contract to Lecon Inc. for construction of the linear detention as one component of a larger project.)
The Harris County Flood Control District is in the design stage for the first phase of a project to construct additional linear stormwater detention along approximately 6.4 miles of Buffalo Bayou between State Highway 6 (just east of the Barker Reservoir) and the Sam Houston Tollway. This area is within Harris County Flood Control District-owned property, acquired from the U.S. Army Corps of Engineers beginning in the 1950s specifically for flood damage reduction purposes. Harris County Commissioner Precinct 3 has constructed, operates and maintains Terry Hershey Park within this portion of Flood Control District-owned property, and the park exists in cooperation with the Flood Control District’s flood damage reduction efforts, including both existing and proposed linear detention.
Preliminary engineering efforts included a due diligence examination of vegetation, environmental and other factors that could impact the project’s feasibility and effectiveness. Conversations about the project with adjoining neighborhoods and organizations have and will continue to take place during the design stage and prior to construction.
From May through October 2018, the Harris County Flood Control District hosted a survey on our website to seek input from area residents as we prepare a project to add linear detention along the south bank of Buffalo Bayou. We want to thank everyone who took the time to complete the survey and offer their thoughts and observations.
Now that the survey has closed, we are glad to address some of the most frequently asked questions and comments from our respondents.
The Flood Control District continues to move projects forward county-wide in response to Hurricane Harvey and other recent record-breaking rain events. Because acquiring right-of-way can be the most challenging and time-consuming aspect of any flood damage reduction project, the Flood Control District is looking first at property it already owns on which to build. The Flood Control District owns approximately 660 acres along Buffalo Bayou between State Highway 6 and the Sam Houston Tollway.
Stormwater detention is a common strategy against flooding in our region. Detention basins can be found in neighborhoods, parks, and open spaces and vary in size and appearance. Linear detention basins are gently sloped areas along the channel that are usually empty of water. During a significant rainfall event, they fill and store the excess stormwater until it is able to naturally drain off, helping reduce flooding in streets and homes.
Linear detention basins are already constructed primarily on the north side of Buffalo Bayou between Dairy Ashford Road and the Tollway. Once constructed and integrated into the surrounding property, linear detention basins exist largely unnoticed as flood reduction components and instead simply resemble a grassy, sloped feature of the landscape.
> Information about preliminary project design -- PowerPoint presentation
The following photos of an existing linear detention basin illustrate how linear detention blends almost seamlessly into an open space, as well as its value for holding water when needed.
It is estimated that an initial phase involving three linear detention compartments on the south bank of Buffalo Bayou between Eldridge Parkway and Dairy Ashford Road could be under construction in 2018. The exact location of individual basin compartments will be determined during the design process, which will take into account construction access and existing trees and other vegetation to minimize environmental impacts such as loss of desirable habitat and wetlands. The overall project will proceed in phases as funding allows.
The addition of linear detention is one step in addressing flooding risks in the Buffalo Bayou watershed. While it would not have likely prevented flooding in Hurricane Harvey or a similar weather event, it would reduce damages from more frequent storms and would serve to increase our defenses against flooding during larger-scale rain events.
This map shows where linear detention (shaded areas) exists on the north banks of Buffalo Bayou today, between Dairy Ashford Road and Wilcrest Drive.
TREES & VEGETATION
Construction of linear detention along Buffalo Bayou likely will require the removal of some trees and vegetation to achieve maximum results. In October 2017, the Flood Control District began tree and vegetation surveys within approximately 177 acres of Flood Control District property between State Highway 6 and the Sam Houston Tollway. The goal of the survey was to provide data needed to catalog existing vegetation and aid in evaluating potential future flood damage reduction projects. Results of the ongoing vegetation survey will be used to minimize removal of any desirable vegetation.
The 2017 survey was intended to complete and update a similar 2014 survey that included approximately 77 acres on the south side of Buffalo Bayou between North Eldridge Parkway and Wilcrest Drive. Additionally, the project will utilize other previous study efforts, including the Charting Buffalo study, as a starting point for identifying the linear detention basin compartments. Previous studies identified environmentally sensitive locations along Buffalo Bayou that will be avoided in this current effort.
The Flood Control District understands that Buffalo Bayou and Terry Hershey Park are special places for many Houstonians. The above-mentioned studies, surveys and other efforts are being made to ensure candidate space is developed in the most thoughtful and effective way possible. Post construction, the area will be folded into the Flood Control District’s Tree Planting Program where we consistently plant from 12,000 to 15,000 trees per year. Existing linear basins within this stretch of Buffalo Bayou feature rolling slopes, native grassy meadows, forested areas and grass banks, and are integrated with Terry Hershey Park trails. A plan for tree replacement will be coordinated with Harris County Precinct 3, which is responsible for maintenance of Terry Hershey Park. It should be noted that the Flood Control District will not design or install recreational features as part of this effort.
IMPACTS FOR LOCAL LANDOWNERS AND PARK VISITORS
In August of 2017, the Flood Control District began communications with landowners who have property bordering the area where additional stormwater detention is being considered. Issues of encroaching fences, fixtures and other personal property are being handled on a case-by-case basis. Impacted landowners will receive additional correspondence to discuss encroachment as it relates to their property and are also encouraged to reach out to the Flood Control District with their questions.
Construction may temporarily impact park and/or trail access. Any closures necessary for public safety reasons will be clearly marked and announced in advance on this webpage.
- Buffalo Bayou from State Highway 6 to what is now the Sam Houston Tollway was straightened, regraded and cleared in the 1940s by the U.S. Army Corps of Engineers, removing many of its original meanders. Since then, trees and other vegetation have naturally grown along this area, giving it a natural appearance. Vegetation also covers man-made mounds created from the placement of material excavated during channelization work.
- The Flood Control District acquired the property beginning in the 1950s from the Corps.
- In 1993, the Flood Control District and Harris County Precinct 3 signed an agreement creating Terry Hershey Park. Harris County Precinct 3 is responsible for trail maintenance and other recreational amenities.
- In the late 1990s and early 2000s, the Flood Control District constructed a series of linear stormwater detention basins on the north side of Buffalo Bayou within Flood Control District lands and Terry Hershey Park. The basins are located mostly between Dairy Ashford and the Tollway. Normally dry, they feature rolling slopes, native grassy meadows, forested areas and grass banks.