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Another Massive Detention Pond Going In Next to Halls Bayou

Construction has begun on another massive detention pond along Halls Bayou. It stretches south from Isom Street to the bayou between Chrisman and Aldine-Westfield Roads. It covers approximately 26 acres and when complete will hold 180-acre feet of stormwater to reduce the risk of flooding. This is just one of 11 projects comprising the Halls Implementation Program. Together they have a total current value of $212 million dollars.

Looking NNW across the new detention pond. Construction started in August 2021. HCFCD expects completion by March 2022.

Such basins take in excess stormwater during heavy rain events and then release it slowly back to the channel when the threat of flooding has passed. Part of the basin will have a wet bottom and another part will have a vegetated shelf. Yet another part will go in between Isom and Aldine Mail Route Road, although that portion has not yet begun construction. (See below).

Map on left shows current extent of construction work. Eventually, project will also include channel conveyance improvements (right) for a tributary that will be directed into the new pond.

Harris County Flood Control District (HCFCD) lists the project as C-25 on its website. But the Flood Bond Program ID is P518-11-00. Ultimately, this will become part of a much larger project area that includes P118-21-00. Together, they will improve drainage in a large part of east Aldine.

Each of these projects falls into Commissioner Adrian Garcia’s Precinct 2. The description that accompanies the project in the flood-bond spreadsheet says, “This project could reduce the risk of flooding for over 90 buildings and could reduce the 1% floodplain for over 100 acres.” The HCFCD spreadsheet and website indicate a total cost of more than $14 million.

But keep this in mind. Project C-25 will work in conjunction with two proposed Harris County Engineering Department projects: neighborhood drainage improvements in the Western Homes subdivision and proposed roadway and drainage improvements along Aldine Mail Route Road. The detention capacity in the pond you see here will accommodate drainage improvements in those areas without flooding other areas. Thus, the pond will really help more than 90 structures.

The project shown in these photos is P-518. P-118 is still in preliminary engineering review.

C-25 is a partnership project. HCFCD received an approximately $9.5 million Community Development Block Grant for Disaster Recovery (CDBG-DR) from the US Department of Housing and Urban Development (HUD). Approximately $5.4 million comes from local funding.

Photos of Work to Date

Looking NE from the SE corner of the construction. Halls Bayou, center, runs along the southern edge of the new basin. The detention basin in the top center was developed by TxDoT. Another phase of this project will expand north into those trees in the upper left.
Looking north from over Halls Bayou. A large part of this basin will have a wet bottom, which contractors are beginning to excavate now. Only detention capacity above the permanent waterline counts toward the total of 180 acre feet. So this pond will have a depth of 7-8 feet from the top of bank to the waterline.
Reverse shot looking SE from Isom Street. The TxDoT basin and Keith Weiss Park are in the upper left of this shot.
The scale of the workers in this shot shows the depth of excavation as of 10/13/21.

This HCFCD presentation explains more about the project, a related project (P118-21-00/C-28) and their benefits.

Posted by Bob Rehak on 10/13/2021

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