Last night, Harris County Flood Control District (HCFCD) revealed its long-awaited recommendations to reduce flood risk along Taylor Gully. The recommendations involve channel improvements, another Woodridge Village stormwater detention basin, and a new bridge at Rustling Elms.
HCFCD is seeking public comment on the plan through December 28, 2022.
Outline of Recommended Alternative
Excessive runoff from Woodridge flooded hundreds of homes in Elm Grove, North Kingwood Forest, and Mills Branch twice in 2019 after a developer clearcut 270 acres without sufficient mitigation.
To fix the problem, HCFCD examined four different alternatives outlined in this presentation, but recommended Option 1. It includes building:
- A concrete-lined, low-flow channel within the existing channel to expand conveyance from 350 feet downstream of Creek Manor Drive to 1500 feet downstream of Mills Branch Drive. The concrete portion would be four feet deep and 20 feet wide.
- An additional dry-bottom, 412.5 acre-foot detention basin on the northern portion of the site.
- A new clear-span bridge at Rustling Elms to replace the current bridge over two culverts.
The recommended alternative would not require any right-of-way acquisition. Translation: no buyouts required.
166% Increase In Stormwater Detention Capacity
Not shown in the diagram above is the stormwater detention basin that Sprint Sand and Gravel is currently working on. Under the terms of their excavation and removal contract with HCFCD, the contractor has up to three years to excavate 500,000 cubic yards. A spokesperson for HCFCD said, “We expect that they will excavate the full amount. The E&R area, like the existing Perry Homes basins, will eventually connect to or become part of the Woodridge detention-basin network to complement the recommended alternative.”
Five hundred thousand cubic yards equals 309 acre feet. With the new pond, that would add 721 acre-feet of stormwater detention to the existing site. The site currently has 271 acre feet of detention. So, the detention volume would increase 166%. It only needed to increase 40% to meet Atlas-14 requirements. Net: the recommended fix should create a considerable margin of safety.
Not Included in Recommendations
The plan does NOT include any improvements near White Oak Creek at the downstream end of Taylor Gully. HCFCD determined that flooding at that end of the channel was caused by backup from White Oak and Caney Creeks.
However, discussion during the meeting suggested that the recommended detention basins further upstream on Taylor Gully could help that area to a minor degree. The plan primarily addresses flooding along and either side of the channel highlighted above to the left of the red circle.
Because of the concrete-lined, low-flow channel conveyance improvements that are a part of the recommended alternative, the existing culverts at Rustling Elms Drive (below) would need to be replaced. See below. An open-span bridge like the one in the background would likely replace it. The current bridge built over culverts (below) backed water up considerably during the 2019 floods and contributed to flooding homes for several blocks on either side of it.
Comparison of Alternatives
HCFCD recommended Alternative #1 because it removes the most structures, acres and roadway from the floodplain for the second lowest cost. Compare the alternatives below. For a fuller description of each alternative, including those not recommended, see the complete presentation.
What Comes Next?
The sequence below outlines project steps. We are currently discussing the preliminary engineering phase. After public comments have been incorporated in that report, HCFCD will deliver it to commissioner’s court and begin final design.
Then, the final design will begin for all improvements. Once complete, the final design will dictate final costs and timing.
To View Video of Meeting and Comment…
HCFCD wants your input. To review the hour-long video of the meeting and/or submit a public comment, see this page (F-14 Taylor Gully Flood Risk Reduction Project).
Posted by Bob Rehak on 12/15/22
1934 Days since Hurricane Harvey