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Texas Water Development Board Approves $30 Million Grant for Mouth Bar Dredging

Today, the Texas Water Development Board formally approved the $30 million grant that will extend the mouth bar dredging program started by the City of Houston last week. Approval had been expected, but in the often-delayed world of flood mitigation projects, the signed deal was a welcome relief. This means that mouth bar dredging can continue in a timely way before hurricane season starts.

Pieces of Puzzle Now in Place

The TWDB grant stemmed from an amendment to SB500 offered by State Representative Dan Huberty in the last legislative session. It will be combined with $6 million that the City had left over from a FEMA grant through the Texas Division of Emergency Management and $10 million allocated to dredging in the 2018 Harris County Flood Bond.

Harris County’s proposal for the grant calls for splitting the project into two phases.

  • Phase One will focus on the West Fork Mouth Bar using the City’s $6 million and $10 million from the grant.
  • Phase Two will focus on the East Fork Mouth Bar using the remaining $20 million from the grant.
  • The $10 million from the County flood bond will fund surveys, formulation of specs, bidding, project management and more.

Going Beyond Harvey Dredging

Since Harvey, dredging efforts have focused on identifying and removing deposits related strictly to Hurricane Harvey itself. See below.

Previous phases of dredging focused upstream of the fat blue area near the mouth bar.

Recently completed projects effectively removed sediment deposited by Hurricane Harvey; however, more dredging needs to be completed in the area farthest to the right. That will help restore conveyance and reduce flooding by removing a sediment dam behind the dam. It should also help improve lake capacity.

Additional details on dredging plans and progress reports should become available in the coming weeks. In the meantime, crews appeared to be busy assembling equipment today at the old docks used by the Army Corps.

Crews assembling braces on pontoon that will hold the spudpoles. The spudpoles will hold the pontoon in place while a mechanical excavator scoops sediment into waiting barges to ferry it back to the placement area. Photo taken 1/16/2020.

The City plans to kick off the program with mechanical dredging equipment because it can mobilize quickly. At some point, they may switch over to hydraulic dredging to take advantage of that technology’s greater efficiencies.

The Great Lakes Dredge from Phase 1 is still sitting at the Army Corps dock in pieces while new equipment mobilizes around it. Rumor has it that the Great Lakes dredge is for sale. Photo taken 1/16/2020.

Huberty has already started lobbying for additional funding to help with longer-term maintenance dredging.

Two More Steps Before Kicking Into High Gear

Late today, John Blount, Harris County Engineer who authored the grant request said that there are two more formalities before the program can kick into high gear.

  • Harris County Commissioners Court, which previously approved the grant request, must now also approve receipt of the award and sign an inter-local agreement with the City of Houston. The latter will govern the working relationship between the City and County. The next Commissioners Court meets on January 28.
  • The permit to use Berry Madden’s property as a placement area must be amended to accept mechanical dredging spoils, not just hydraulic.

Posted by Bob Rehak on 1/16/2020

870 Days since Hurricane Harvey

Harris County Approves TWDB $30 Million Grant Application for Dredging at Confluence of San Jacinto and Lake Houston

In the last legislative session, State Representative Dan Huberty sponsored an amendment to Senate Bill 500. The amendment earmarked a $30 million grant for additional dredging at the confluence of the San Jacinto River and Lake Houston. Last week, Harris County approved the grant application to the Texas Water Development Board. That will actually transfer the money so that it can be put to work.

How $30 Million Grant Would Be Spent

County Engineer John Blount explains how the money would be spent in his cover letter that accompanied the request to Commissioners.

“The approach to completing work under the grant,” says Blount, “would be for the County to receive the grant funds, make the City of Houston a subrecipient to start immediate dredging, and to develop a long-term plan for keeping the region’s raw water supply viable with adequate reservoir capacity. The County would be reimbursed from the grant for administrative and other related expenses incurred.”

County Plays Central Role In Coordinating Effort

Blount concludes, “If authorized, the County will work with the Flood Control District, Budget Office, County Attorney, City of Houston, and the State of Texas, to advance all necessary applications and agreements needed to initiate the dredging activities funded in the 2019 legislative session. Grant awards, if made, will be presented to Commissioners Court for consideration at a future date.”

Commissioners Court approved the motion unanimously in its Tuesday, December 17th meeting. And by Friday, the actual grant application had been sent to the TWDB, according to Matt Zeve, Deputy Executive Director of Harris County Flood Control. The TWDB board should consider the request at its first board meeting in January, tentatively scheduled for the 10th. Huberty expects quick approval because the Legislature earmarked the money specifically for this purpose.

Water Supply, Not Just Flood Mitigation, An Issue

Dredging affects more than flood mitigation. It also affects water capacity for Lake Houston. The lake supplies drinking water for 2 million people. The Interbasin Transfer Project will soon bring 500,000 gallons per day from the Trinity River. But a growing East Fork mouth bar could soon block Luce Bayou. That’s where the water will enter the lake to be used by the Northeast Water Purification Plant.

As a result of sediment deposited during Harvey and Imelda, the East Fork Mouth Bar grew southward 4000 feet and now has almost reached the point where Luce Bayou and water from the Trinity River will enter Lake Houston. Photo taken 12/3/2019. Water flows from left to right.

West Fork Also Plays Role in Water Transfer

That’s also why the West Fork must remain clear. It brings water, when needed, from Lake Conroe.

Looking south across the mouth bar of the San Jacinto West Fork toward Lake Houston. Photo taken 12/3/2019.
Reverse angle. Looking northwest toward the San Jacinto River and the West Lake Houston Parkway Bridge. Note the submerged sand about to break through the water surface around the mouth bar. Photo taken 12/3/2019.
Kayaker RD Kissling standing in less-than-knee-deep water 700 yards south of the West Fork Mouth Bar. Photo taken November, 2019.

Like icebergs, sand bars mostly exist below the surface. What you see above water is a small percentage of what exists below water.

These photos illustrate why more dredging is essential. The mouth bars form dams behind the dam that block the free flow of water and decrease reservoir capacity.

Exploring Most Cost-Effective Options for Future

Between June when the Legislature approved the money and now, the City, County and State have explored ways to work together to ensure they spend the money cost-effectively. The county hired a consultant to explore the merits of do-it-yourself dredging vs. hiring a contractor. At the moment, the partners lean toward the contractor approach. It offers long-term flexibility as they explore future needs around the lake.

In addition to the $30 million from the State, the City of Houston allocated $6 million from money left over from Harvey disaster recovery funds. The County also allocated $10 million in its flood bond for dredging.

Initial Disposal Site Already Approved

The Army Corps approved Barry Madden’s property as a disposal site for the spoils. Madden’s property is opposite River Grove Park. That puts it miles closer to the Mouth Bar than previous placement areas used by the Corps. That should reduce costs by reducing the need for booster pumps and fuel.

The pieces of the puzzle are starting to come together.

Posted by Bob Rehak on 12/23/2019

846 Days since Hurricane Harvey and 95 since Imelda