Tag Archive for: gates

TWDB to Consider $50 Million Grant for Lake Houston Gates

Save the date. On December 7, 2023, the Texas Water Development Board will consider a $50 million grant to the City of Houston for structural improvements to the Lake Houston Dam. The improvements will extend the life of the dam and enable rapid lowering of lake levels in advance of a flood.

The project, led by outgoing Houston Mayor Pro Tem Dave Martin and Chief Recovery Officer Stephen Costello, will benefit thousands of residential properties in the surrounding area.

Make sure the next mayor supports it. Get out and vote. Better yet, take your neighbors with you!


The $50 million grant will complement funds from other sources including FEMA. The addition of new tainter gates will enable Lake Houston to shed water faster before and during storms, reducing the risk of flooding.

Until now, pre-releasing water has been risky. The old gates on the Lake Houston dam can release only 10,000 cubic feet per second. As a result, to significantly lower the lake, releases must start far in advance of a storm. But storms can veer away during that extended time. That increases the chances that the City could waste water.

After several years of study, the City has found that the optimal option would be to add tainter gates to the eastern, earthen portion of the dam. But the cost increased significantly compared to the crest gates initially favored.

Proposed location for new tainter gates
Proposed location for new tainter gates.

Earlier this year, the Legislature set aside more funds for the new tainter gates and specifically directed the Texas Water Development Board (TWDB) to provide those funds. The TWDB’s executive administrator has recommended authorizing the funds. The Board just needs to approve them.

TWDB Board Meeting In Houston

The TWDB board will consider the approval at a rare Houston meeting at the Harris County Flood Control District in early December.

Thursday, December 07, 2023; 9:30 AM
In person at 7522 Prairie Oak Drive
Michael Talbott Pavilion, Harris County Flood Control District Service Center
Houston, TX 77086

To view the webinar online, you must register for details.

Visitors who wish to address the Board should complete a visitor registration card and attend the meeting in person. The Texas Open Meetings Act prohibits visitor participation by telephone only. The visitor registration card is available and should be completed and submitted by e-mail to Customer Service no later than 8:00 a.m. on December 7, 2023, or in person at the registration desk.

Here is the full agenda. The $50 million grant for more gates is #14. Here is the backup information.

New, higher capacity gates were one of the three primary recommendations made by the Lake Houston Area Task Force after Harvey to mitigate flooding in the area. If all goes according to plan, construction could start in mid-2026, according to Costello.

Will Next Houston Mayor Support the Project?

Large infrastructure projects like this depend on unwavering political support. Completion of this project could take until the NEXT mayoral election. In the meantime, make sure we elect a mayor who will support the Gates Project until then. Keep it moving forward.

In that regard, John Whitmire has already demonstrated his support. If you haven’t yet voted, make sure you do. Take your neighbors, too. And then walk around your block and knock on some doors. Keeping this project will depend on turnout in the current runoff election.

So far, Acres Homes has had eight times more early voters than Huffman. And fewer than 4,000 people have voted in Kingwood.

As of 12/1/2023 according to Harris Votes.

The last day for early voting is December 5th. Polls are open from 7 am to 7 pm except for Sunday when they open at noon. Your last chance to vote is on Election Day, December 9th. For complete election information, visit Harris Votes.

Posted by Bob Rehak on 12/1/2023

2285 Days since Hurricane Harvey

SJRA Appoints Aubrey Spear New General Manager

November 15, 2023 – The San Jacinto River Authority (SJRA) Board of Directors announced today the selection of Aubrey A. Spear, PE, as general manager.

Aubrey Spear


As general manager, Spear will oversee the development and implementation of SJRA’s vision, mission and strategic goals through the collaboration with the SJRA’s Operating Divisions: General and Administrative Services, Lake Conroe, Woodlands, Groundwater Reduction Plan, Highlands, and Flood Management. In addition to providing managerial oversight, Spear will be instrumental in overseeing the development and execution of capital improvement plans, planning, external affairs, leadership development, and budget.

SJRA Board President Ronnie Anderson expressed confidence in Aubrey Spear’s arrival saying, “After a thorough search, the SJRA Board of Directors is proud to welcome Aubrey to SJRA. Aubrey’s extensive experience in water utility management, water and wastewater infrastructure projects, and stakeholder relationships make him a great fit for our team.”


“I am excited to join the dedicated team at SJRA,” said Spear. “I look forward to collaborating with key stakeholders including employees, customers, and elected officials to determine major areas of focus for the Authority moving forward. I am passionate about implementing the river authority’s vision to provide reliable, cost-efficient, and sustainable water resource management that supports the significant growth in the region while earning the trust and confidence of our customers and community.” 


Aubrey Spear brings extensive professional leadership and managerial experience to SJRA. He served the City of Lubbock in a senior management role as Director of Water Utilities for 16 years leading the city’s Water Utilities Department of more than 200 employees. Additionally, he served as liaison to multiple water boards including the Lubbock Water Advisory Commission, Canadian River Municipal Water Authority, High Plains Underground Water Conservation District and served as the chairperson of the Region O Water Planning Group and on the executive committee of the Upper Brazos Regional Flood Planning Group. 

Spear has also guided public relations, marketing, and customer service activities and facilitated major projects including the city of Lubbock’s first new surface water supply reservoir in more than 25 years, Lake Alan Henry. 

Spear will start with SJRA in January 2024.


Aubrey Spear’s appointment comes almost six months after Jace Houston resigned from SJRA at the end of May 2023.

After 16 years with the SJRA, Houston had become the focus of criticism over a groundwater reduction plan designed to reduce subsidence and ensure the water future of Montgomery County. Houston had led the conversion from dwindling groundwater to surface water. That included construction of a water treatment plant at Lake Conroe and several water distribution pipelines.

However, several signatories to the Groundwater Reduction Plan eventually balked at higher prices despite the reduction in subsidence. Conroe state representative Will Metcalf proposed an amendment to the SJRA’s sunset review bill that would have ousted Houston had the state senate supported it.

As Spear prepares to navigate new waters in SE Texas, he will be forced to thread a needle between downstream and upstream interests.

Memories of the SJRA’s role in downstream flooding during Harvey when it released 79,000 cubic feet per second from Lake Conroe will constrain him. So will the reluctance of Lake Conroe residents to live with seasonally lower lake levels. Lake lowering didn’t generate much controversy this year. Because of drought, lake lowering wasn’t necessary.

However, it could in the future if the project to add more flood gates to Lake Houston ever gets off the drawing boards.

Posted by Bob Rehak on 11/15/23 based in part on a press release from SJRA

2269 days since Hurricane Harvey

Update on Floodgates, Dredging, Sand Traps from Martin, Costello

At Mayor Pro Tem Dave Martin’s final town hall meeting last night, he and Chief Recovery Officer Stephen Costello gave an update on the status of new, higher capacity floodgates for the Lake Houston Dam. Their talks also addressed dredging and sand traps.

City of Houston Chief Recovery Office Stephen Costello (l) and Mayor Pro Tem Dave Martin at Martin’s final town hall meeting on 10/17/2023. Term limits bar Martin from running again for Council, though he is running for City Controller.

According to the latest estimate, construction of the gates now looks like it could begin in mid-2026, barring unforeseen setbacks.

The City has scheduled more dredging for the San Jacinto West Fork south of where the mouth bar used to be. Also, Costello says the City has completed opening up ditches and tributaries north of the railroad bridge and is now starting on those south of it.

Finally, Costello revealed that Lake Houston has lost almost 20% of its capacity due to sedimentation. To receive future dredging grants, the City must take steps to reduce the rate of sediment inflow. Costello revealed plans for a pilot sand-trap project in a point bar outside the Hallett mine far upstream. He said that the mine had agreed to remove trapped sediment there for free. Otherwise, he did not explain why a possibly more effective location closer to the problem area was not chosen for the pilot project.

For more details on each, see below.

Gates Details/Timeline

The purpose of adding more floodgates to the Lake Houston Dam: to lower the lake faster in advance of a flood.

  • The City must now start to lower the lake so far in advance of a storm that storms can veer away before they arrive. This wastes water.
  • The existing gates have 1/15th of the release capacity of the gates on Lake Conroe. This makes a joint pre-release strategy virtually impossible in extreme storms.

After examining and discarding the notion of adding crest gates to the spillway portion of the dam, the City is now focusing on adding 11 tainter gates to the earthen portion of the dam (east of the existing gates).

Proposed location for 11 new tainter gates.

With Mayor Sylvester Turner’s help, the City secured enough funding for construction during the regular session of this year’s legislature.

Next steps include:

  • 3/24 – New environmental and historic preservation assessments, Army Corps permitting
  • 12/24 – Construction plans completed
  • 1/25 – Bidding
  • 6/25 – Award Contract
  • 5/26 – Begin Construction

The success of this plan will require the election of a new Mayor and City Council Representative who are committed to the project. Early voting begins next week.

Dredging Volumes, Costs

Dredging at various locations around Lake Houston will likely be a continuous effort for years to come. Sedimentation has already reduced the capacity of Lake Houston an estimated 18%. The City estimates future yearly losses in the range of 360-460 acre feet per year.

Historic and projected capacity loss in Lake Houston due to sedimentation.

One acre roughly equals the size of a football field. So imagine 400 football fields covered with sludge a foot deep. Each year!

To keep this problem in check, the City is already looking at doing additional dredging on the East and West Forks. It and the Army Corps finished major projects in both areas less than four years ago.

East of Atascocita and south of the convergence of the East and West Forks, the City plans to spend another $34 million to remove almost 900,000 cubic yards of sediment.

To date, Costello estimates that dredging nearly 4 million cubic yards of material has cost $186 million.

Summary of dredging costs and volumes in Lake Houston since Harvey

The City hopes to recoup some of these costs by reselling sand that it recovers from “hilltops” in the lake. Costello showed the heat map below. Notice the heavy sediment concentrations in the lake’s headwaters. This is because sediment drops out of suspension where rivers slow down as they meet standing bodies of water.

In addition to reducing the volume of Lake Houston, the sediment also poses a flood threat. It reduces conveyance of the rivers and lake forcing water up and out. Sediment blockages, such as the mouth bar, can also form dams that back water up.

Costello also addressed the ongoing dredging of 17 canals around Lake Houston. He said the focus is now shifting to the southern part of the lake.

Sand Traps to Reduce Inflow

In addition to dredging sediment from the lake, Costello also emphasized the need to reduce sediment coming downstream via sand traps. This last effort may be a condition of future grants for dredging.

Costello described two pilot types of pilot projects that the City is working on with the SJRA and sand-mining industry. The first is “sand traps” dug in point bars outside sand mines. The second: in-channel traps.

The idea behind the traps: dig holes in the river or its sand bars where migrating sand can settle out of the flow before it reaches the lake.

The first project may be near the Hallett Mine on the West Fork. According to Costello, the mine has agreed to remove the sand for free, thus reducing long term maintenance costs.

During Q&A after Costello’s presentation, however, he admitted that the City has no plans to try to get sand mines to reduce illegal emissions. In one notable instance, the TCEQ documented 56 million gallons of sludge discharged into the West Fork by the LMI mine.

Controlling sediment is crucial in reducing flooding. Accumulated sediment reduces storage capacity and conveyance for stormwater. The smaller capacity means lakes and rivers will flood faster and higher.

For high res versions of all the slides shown in the Town Hall, see this PDF.

Posted by Bob Rehak on 10/17/23

2241 Days since Hurricane Harvey

Last-Minute Funding Breathes New Life into Lake Houston Gates Project

The project to install more flood gates on the Lake Houston Dam has resulted in more nail-biting than a Steven Spielberg movie. Perhaps no project inspired more hope among flood-weary home- and business owners in the San Jacinto watershed. Importance is high, but the costs turned out far higher than expected and dollars proved hard to come by.

This morning, however, Dr. Greg Bonnen, chair of the House Appropriations Committee filed a rider to this year’s appropriations bill that will likely get the job done. The rider contains two provisions that affect funding for the gates.

  • Sec. 17.38 (a)(1) on page IX-22 contains $50 million for improvements to the Lake Houston Dam.
  • Sec. 17.38 (b)(1)(2)(3) on page IX-23 contains a provision that lets unexpended balances from previous grants be redeployed, so they can be spent on EITHER gates, a sediment capture pilot project, or sediment removal.
Lake Houston has four small floodgates only capable of releasing 1/15 the rate of Lake Conroe’s gates. New gates would go in the earthen embankment to the right of the old gates and spillway.

Funding Now Close to Expected Costs

According to Houston Mayor Pro Tem Dave Martin, Black & Veatch Engineering estimates the cost of an 11-gate structure to be between $125 and $225 million.

Balancing that on the income side of the ledger are:

  • The remaining Federal funds of the $50 million provided by FEMA early on for engineering, environmental surveys, permits and construction. So far the City has reportedly spent about $5 million on upfront work.
  • An $8 million earmark by US Congressman Dan Crenshaw.
  • $20 million in County funds allocated in the 2018 Flood Bond (Project CI-61).
  • $11 million from the City of Houston in capital-improvement-project (CIP) funds.
  • The possibility of additional CIP funds from this year’s budget.
  • $50 million from 17.38 (a)(1) above
  • Up to another $50 million in State funds left over from a TWDB 2021 allocation in 17.38 (b)(1)(2)(3)
  • Redeployment of some FEMA dredging funds left over from the Mouth Bar Project.

That puts available funding somewhere north of $170 million. Martin says that should be enough to lock in the original FEMA funding and get the project started.

Redeployment of Funds Important

Congressman Crenshaw’s office emphasized that even though some FEMA money will be redeployed from dredging the mouth bar, additional FEMA funds from another FEMA grant will let dredging around the lake continue.

Re: 17.38 (b) above (that second bucket of $50 million in funding from the state) Martin points out that it includes two other important projects: dredging and the sediment trap pilot study. However:

  • The pilot study should not be very expensive and has no firm deadline.
  • Congressman Dan Crenshaw has helped secure additional funding for dredging from a second FEMA grant.

Finally, Martin points out that Black & Veatch is examining options to scale back the number of gates in case construction costs exceed funding if something falls through.

Enough Funding Committed to Move Forward with Confidence

While some uncertainty remains, Martin says the key point is that enough money has now been committed to move forward with confidence. This is a huge improvement over where the project stood just 8 days ago when concerned residents launched a call-in campaign to influential senators and representatives.

Lake Houston Area residents placed thousands of calls to save the project. Two days later, funding was placed in Bonnen’s rider. Martin thanks “ALL who placed phone calls, sent text messages and emailed state officials in support of our gates project.”

Thank you’s also go to all those who played key roles in this up-against-the-center-field wall catch:

  • State Senator Brandon Creighton
  • State Representative Charles Cunningham
  • Lieutenant Governor Dan Patrick
  • State Representative Armando Walle
  • State Senator Joan Huffman
  • House Speaker Dade Phelan
  • House Appropriations Chairman Greg Bonnen
  • Houston Mayor Sylvester Turner
  • US Representative Dan Crenshaw and Kaaren Cambio, his District Director

Several others deserve special thanks:

  • Mayor Pro Tem Dave Martin worked the phones relentlessly and made countless trips to Austin to raise awareness of the project and coordinate the area’s efforts.
  • City of Houston Chief Recovery Officer Stephen Costello convinced FEMA to include social benefits in the cost/benefit ratio (CBR). That raised the CBR to 3.5, making it the highest-rated project in the State of Texas.
  • City of Houston Mayor Sylvester Turner, who called in some favors among Austin influentials to make the project happen.
  • Former State Representative Dan Huberty and Ben Melson, a CoH lobbyist, lobbied extensively over the last few months, working with Martin, Costello and Bill Kelly, the City’s Director of Government Affairs.

Reason More Gates Needed

Additional gates will let the City lower lake water faster as large storms approach, thus reducing flood peaks both upstream and down. That will, in turn, reduce flood risk for thousands of homeowners and businesses, not to mention all the schools that flooded.

But lowering the lake level carries some risk. If it takes too long to lower the lake, storms can veer away before they arrive, wasting water. Narrowing the window between release and the storm’s arrival, raises certainty that the storm will refill the lake.

More gates will also help balance releases from Lake Conroe with those from Lake Houston.

Next Steps

It ain’t over till it’s over. But even though only days are left in this session, Chairman Bonnen’s office said, “The legislature has never failed to pass an appropriations bill.”

More news as the project evolves.

Posted by Bob Rehak on 5/25/2023

2095 Days since Hurricane Harvey

Lack of Support in Legislature Putting Lake Houston Gates Project in Danger

Lack of support by the Texas State legislature is putting the project to add more floodgates to the Lake Houston dam in danger. Right now, money is not in the appropriations bill for the next two years. And if we have to wait for another two years, the initial $50 million committed by FEMA to the project will expire.

Call to Action

Please CALL the following elected representatives to voice your support for including $150 million for Lake Houston Floodgates in next year’s state budget. Also, get everyone you know to call.

At a minimum, call:

  • Governor Greg Abbott: (512) 463-2000
  • Lieutenant Governor Dan Patrick: (512) 463-0001
  • Sen. Brandon Creighton: (512) 463-0104
  • Rep. Greg Bonnen: (512) 463-0729, Chair of House Appropriations
  • Sen. Joan Huffman: 512-463-0117, Chair of Senate Finance Committee
  • Sen. Robert Nichols: 512-463-0103

Other key decision makers:

  • Rep. Mary González – (512) 463-0613
  • Rep. Jacey Jetton – (512) 463-0710
  • Rep. Gary VanDeaver – (512) 463-0692
  • Rep. Armando Walle – (512) 463-0924
  • Sen. Lois Kolkhorst – (512) 463-0118
  • Sen. Charles Schwertner – (512) 463-0105

Remind Governor Abbott that when he toured Lake Houston after Harvey, he directed area leaders to develop long-range solutions that fixed the flooding problem. So…

Ask everyone to ensure funding for the Lake Houston Dam Improvement Project.

Here’s why.

Why We Need More Gates

After Hurricane Harvey, Lake Houston Area leaders identified adding more release capacity to the dam as one of the area’s top flood mitigation priorities. The inability to release water fast enough in advance of Harvey contributed to flooding 16,000 homes and 3,300 businesses.

If Lake Houston could release more water faster, authorities could wait until they were certain a storm would hit our area before releasing water. Releasing water would create more room for floodwater. But if the storm veers away and we release the water unnecessarily, it could cause a water shortage for 2 million people.

More gates would eliminate that risk/uncertainty.

Progress But Still No Permanent Solution

Rainfall this past week has demonstrated the problem once again. There was no tropical storm. No hurricane. No stalled front. Just widespread, sporadic downpours. Even with Lake Houston’s gates wide open and two feet of water cascading over the spillway, areas around the lake are still flooding.

River Grove Soccer Fields
River Grove Park on 5/16/23

It happens repeatedly.

January Flooding along west fork of San Jacinto
The first flood this year occurred in January.

And bigger storms can cause horrific damage.

Hurricane Harvey destroyed Union Pacific Railroad Bridge that parallels US59 in the headwaters of Lake Houston. The damage disrupted rail traffic in an out of Houston for almost three years.
San Jacinto West Fork at US59 during Harvey
US59 Bridge and Humble business district underwater during Harvey

Preliminary engineering studies showed that more gates could reduce flood levels significantly. FEMA appropriated $50 million to build them. But additional studies showed we need more gates that will quadruple the cost. We need $150 million more.

Support of Area Representatives and Organizations Not Enough

The state legislature is the only place to get that money before the FEMA grant expires. More than a dozen area organizations and elected representatives have already written letters to legislators in support of the project – to no avail.

Significantly, support comes from both upstream and downstream.

Montgomery County people want this project as much as Harris County people, because it would enable Lake Conroe to avoid seasonal lowering.

See letters from:

Harris County Precinct 3 Commissioner Tom Ramsey, PE, to Governor Greg Abbott

Harris County Precinct 3 Commissioner Tom Ramsey, PE, to Lieutenant Governor Dan Patrick

Harris County Precinct 3 Commissioner Tom Ramsey, PE, House Speaker Dade Phelan

North Houston Association to Governor Greg Abbott

North Houston Association to Lieutenant Governor Dan Patrick

North Houston Association to House Speaker Dade Phelan

Partnership Lake Houston to Governor Greg Abbott

SJRA to State Senator Brandon Creighton

SJRA to Senator Joan Huffman

SJRA to Senator Charles Perry

Lake Conroe Association to Senator Brandon Creighton

Lake Conroe Association to Senator Robert Nichols

Lake Houston Redevelopment Authority to Governor Greg Abbott

City of Houston Mayor Pro Tem Dave Martin to Governor Greg Abbott

City of Houston Mayor Pro Tem Dave Martin to Lieutenant Governor Dan Patrick

City of Houston Mayor Pro Tem Dave Martin to House Speaker Dade Phelan

Harris County Flood Control District to Governor Greg Abbott

Harris County Flood Control District to Lieutenant Governor Dan Patrick

Harris County Flood Control District to House Speaker Dade Phelan

City of Humble Mayor Norman Funderburk to Governor Greg Abbott

Kingwood Service Association to Governor Greg Abbott

Kingwood Service Association to Lieutenant Governor Dan Patrick

Kingwood Service Association to House Speaker Dade Phelan

Greater Houston Partnership to the entire Houston Delegation

Kingwood Area Superneighborhood Council to Governor Greg Abbott

Kingwood Area Superneighborhood Council to Lieutenant Governor Dan Patrick

Kingwood Area Superneighborhood Council to Houston Speaker Dade Phelan

Humble ISD to Governor Greg Abbott

Humble ISD to Lieutenant Governor Dan Patrick

Humble ISD to Dade Phelan

Montgomery County Judge to Governor Greg Abbott

Montgomery County Judge to House Speaker Dade Phelan

Montgomery County Judge to Senator Brandon Creighton

Montgomery County Judge to Senator Lois Kolkhorst

Montgomery County Judge to Lieutenant Governor Dan Patrick

Montgomery County Precinct 4 to Governor Greg Abbott

Montgomery County Precinct 4 to Lieutenant Governor Dan Patrick

Montgomery County Precinct 4 to House Speaker Dade Phelan

Greater East Montgomery County Chamber to Governor Greg Abbott

Greater East Montgomery County Chamber to Lieutenant Governor Dan Patrick

Greater East Montgomery County Chamber to House Speaker Dade Phelan

Time for Residents to Add Their Voices

At this time, we need to start a telephone campaign by residents. NOW! This session ends in days.

Please voice your support for the project by calling the offices of Governor Abbott, Lieutenant Governor Patrick, Senator Creighton, and Rep. Greg Bonnen, chair of the House Appropriations Committee. Ask them to add $150 million for more Lake Houston floodgates in next year’s state budget.

You could make the difference.

Posted By Bob Rehak on 5/17/2023

2087 Days since Hurricane Harvey

City Gets Favorable Ruling on BCR for Lake Houston Gates Project

During Harvey, 16,000 homes and 3,300 businesses in the Lake Houston Area flooded. Local leaders identified the disparity in release capacities between the Lake Conroe and Lake Houston Dams as one of the contributing factors to the severity of flooding. The floodgates on Lake Conroe can release water 15 times faster than the gates on Lake Houston. So, adding more floodgates to Lake Houston became one of the area’s primary mitigation goals.

New gates would let the City rapidly lower the water level of Lake Houston in advance of a storm to prevent or reduce upstream flooding.

gates for Lake Houston and Conroe
Lake Houston (l) and Lake Conroe gates (r). Conroe release capacity is 15X greater.

While the City of Houston initially obtained a $50 million grant from FEMA to add gates, two problems became apparent. The project cost more than anticipated and the benefits delivered did not justify the cost – at least the way FEMA was initially calculating them. However, a huge hurdle has been cleared.

The City of Houston has finally secured a favorable ruling from FEMA on a benefit-to-cost ratio, according to a press release from Mayor Pro Tem Dave Martin’s office on 12/7/2022. The key was the FEMA administrator’s decision to allow the inclusion of social benefits, for instance, avoidance of disruptions to business, commerce, schools and the area’s tax base. Those brought the BCR up to 2.88, according to Martin.

Hurdle Removed: Project Now Federally Compliant

Earlier this summer, Martin announced challenges related to the Lake Houston Spillway Dam Improvement Project. The City needed to secure a benefit to cost ratio (BCR) between .75 and 1 and had examined multiple alternatives to find a favorable balance between costs and benefits.

Martin, Mayor Sylvester Turner and Chief Recovery Officer Stephen Costello met with the Federal Emergency Management Agency (FEMA) Administrator to discuss the inequities of the Federal BCR formula associated with incorporation of social benefits.

As a result, Martin and Turner have announced that a large hurdle has been removed. The revised draft BCR for the Lake Houston Spillway Dam Improvement Project has been determined to be “federally compliant and is very favorable.”

The change affected the Lake Houston Gates and several other Houston stormwater projects including the massive, new Inwood Forest detention basin.

New BCR Based on Eleven Gates

Atkins, a City of Houston consultant, revised the BCR for an eleven-gate structure. The eleven gates will be built into the existing embankment on the east side of the Lake Houston Spillway Dam.

New gates would be added to the earthen portion of dam in foreground, not spillway at far end as originally planned.

Building the new gate structure in the east embankment removes the high construction risk of modifying the existing gate structure. It also allows continued use of the existing gate structure during construction, and eliminates the need for a coffer dam in the lake, according to Martin.

The new gates would likely align with the original course of the San Jacinto River, the channel on the left.

Cost Quadruples: Additional Funding Sources Now Necessary

The new preliminary cost estimate of $200 million exceeds the City’s original FEMA grant of $48 million.

Martin, Costello, and State Representative Dan Huberty have already met with the Texas House of Representatives Speaker Dade Phelan’s Director of Finance regarding additional funding. They have positioned the project as a “life and safety initiative” that affects the survival of the community and economy of the Lake Houston Area.

Martin has bi-partisan support already lined up for financing. Key partners this legislative session include:

  • Congressman Dan Crenshaw
  • State Senator Brandon Creighton
  • State Senator John Whitmire (who has already announced his intention to run for Houston mayor after Turner retires)
  • Speaker of the Texas House Dade Phelan
  • State Representative & Chair of Appropriations Dr. Greg Bonnen
  • State Representatives Charles Cunningham and Armando Walle.

Martin plans to work with Federal and State partners to ensure the cost of the Lake Houston Spillway Dam Project is fully funded before he leaves office in December 2023.

Said Martin, “Today a significant obstacle has been surpassed as this project moves forward through the financial process.” The new BCR should let federal, state, and local partners work toward fortifying the Lake Houston Area against future storms.

It would be unfair to call this a “start over.” A huge amount of engineering and analysis has gone into the project. However, challenges turned out to be greater than anyone anticipated after Harvey.

The original timetable from 12/16/19 showed the project completed by now. The fact that it is still alive is a tribute to the persistence of Martin, Turner, Costello and others.

Let’s look forward to the benefits, not backwards to the problems. People are working in the right direction. A huge obstacle has been eliminated. We just need to keep tackling new obstacles as they occur. Next step: the House and Senate.

I will post construction plans for the 11 gates and the Atkins’ BCR analysis as soon as the City supplies them; they promised they would.

Posted by Bob Rehak on 12/7/22

1926 Days since Hurricane Harvey

Harvey: A 5-Year Flood-Mitigation Report Card

Tomorrow is the fifth anniversary of Hurricane Harvey. Many in the Lake Houston Area have asked, “Are we safer now?” The answer is yes, but we have a long way to go to achieve all our goals. Here’s a five-year flood-mitigation report card. It describes what we have and haven’t accomplished in 29 areas. So get ready for a roller coaster ride. I’ll leave the letter grades to you.

Lake Houston Area Mitigation

1) Dredging

The most visible accomplishment in the Lake Houston Area since Harvey is dredging. The City and Army Corps removed approximately 4 million cubic yards of sediment blocking the West and East Forks. Before dredging, River Grove Park flooded six times in two months. Since dredging, it hasn’t flooded once to my knowledge.

west fork mouth bar before dredging
West Fork mouth bar after Harvey and before dredging. Now gone, but not forgotten.

State Representative Dan Huberty secured additional funding during the last legislature to continue maintenance dredging. That includes clearing drainage canal outfalls into the lake, such as the entrance to Rogers Gully. The dredging operation is now moving around the lake, according to the City’s District E office.

2) Adding Floodgates

Engineers keep looking for a cost-effective alternative. They first identified 11 options in a preliminary review. They then studied the most promising – spillway crest gates – in more detail. Now they’re looking at tainter gates in the earthen portion of the dam. In case the Benefit/Cost Ratio still doesn’t meet FEMA requirements for moving forward with construction, Houston Mayor Pro Tem Dave Martin is also exploring additional funding sources. But so far, no construction has started on additional gates. Martin hopes to reveal a recommendation in September.

Lake Houston Dam, area for new gates
Potential location for new tainter gates east of the spillway portion of the dam (out of frame to the right.
3) Upstream Detention

To reduce the amount of water coming inbound during storms, the San Jacinto River Basin Master Drainage Study identified 16 potential areas for building large stormwater detention basins. Unfortunately, they had a combined cost of $3.3 billion and would only reduce damages by about a quarter of that.

So, the SJRA recommended additional study on the two with the highest Benefit/Cost Ratio. Their hope: to reduce costs further. The two are on Birch and Walnut Creeks, two tributaries of Spring Creek near Waller County. Expect a draft report in February next year.

Funding these would likely require State assistance. But the Texas Water Development Board’s San Jacinto Regional Flood Planning Group has just recently submitted its first draft report. The draft also recommended looking at detention basin projects on West Fork/Lake Creek, East Fork/Winters Bayou, and East Fork/Peach Creek.

Building them all could hold back a foot of stormwater falling across 337 square miles. But funds would still need to be approved over several years. We’re still a long way off. Results – on the ground – could take years if not decades.

4) “Benching”

The Regional Flood Planning Group also recommended something called “benching” in two places along 5 miles of the West Fork. In flood mitigation, benching entails shaving down a floodplain to create extra floodwater storage capacity. Like the detention basins, benching is still a long way off…if it happens at all.

5) West Fork Channel Widening

Finally, the Regional Flood Planning Group recommended widening 5.7 miles of the West Fork to create more conveyance. But again, at this point it’s just a recommendation in a draft plan.

San Jacinto River Authority

6) SJRA Board Composition

After Harvey, many downstream residents accused SJRA of flooding downstream areas to save homes around Lake Conroe. At the time, SJRA’s board had no residents from the Humble/Kingwood Area. So Governor Abbott appointed two: Kaaren Cambio and Mark Micheletti. Cambio later resigned due to a potential conflict of interest when she took a job with Congressman Dan Crenshaw. That leaves Micheletti as the lone Humble/Kingwood Area resident on a seven-person board. However, the SJRA points out that the Board’s current president, Ronnie Anderson, represents Chambers County, which is also downstream.

State Representative Will Metcalf, who represents the Lake Conroe area, introduced a bill to limit SJRA board membership to upstream residents. Luckily for downstream residents, it failed.

7) Lake Conroe Lowering

SJRA identified temporary, seasonal lowering of Lake Conroe as a strategy to reduce downstream flood risk until completion of dredging and gates projects in the Lake Houston Area. The lowering creates extra storage in the lake during peak rainy seasons. After SJRA implemented the plan, Lake Conroe residents objected to the inconvenience. They sued SJRA and the City, but lost. After discussion with all stakeholders, the SJRA quietly modified its plan. It still lowers the lake, but not as much.

8) Lowering Lake Houston

Houston also started lowering Lake Houston, not seasonally, but in advance of major storms. The City has lowered the lake more than 20 times since beginning the program. That has helped to avoid much potential flooding to date.

9) Lake Conroe Dam Management

SJRA applied for and received several TWDB grants to enhance flood mitigation and communications in the San Jacinto River Basin. One involves developing a Lake Conroe Reservoir Forecasting Tool. SJRA has also worked with San Jacinto County to develop a Flood Early Warning System.

Finally, SJRA’s Lake Conroe/Lake Houston Joint Reservoir Operations Plan is on hold pending completion of the City’s plan to add more gates to the Lake Houston dam. Such projects may help reduce the risk of releasing unnecessarily large volumes of water in the future.

Coordination between Lake Conroe and Lake Houston has already improved. You can see it in the SJRA’s new dashboard. It shows releases requested by the City of Houston to lower Lake Conroe.

10) Sediment Reduction

Huge sediment buildups in the West and East Forks of the San Jacinto clearly contributed to flooding. The Army Corps stated that the West Fork was 90% blocked near River Grove Park. To reduce future dredging costs, SJRA also studied the use of sediment traps. SJRA may implement a pilot study soon on the West Fork near the Hallett mine.

However, the location is controversial. Geologists say it wouldn’t reduce sediment in the area of greatest damage. Environmentalists worry that it could increase sedimentation through a “hungry-water” effect and open the door to river mining. And I worry that, even if successful, the pilot study would not be extendable. That’s because it relies on partnerships with sand miners. And other tributaries to Lake Houston do not have sand mines or as many sand mines.

Sand bar blocking West Fork after Harvey. The Corps has since removed it.

Federal Funding

It’s hard to get good grades on your flood mitigation report card without funding.

11-18) Appropriations

In March this year, Congressman Dan Crenshaw secured appropriations that should help advance projects in the San Jacinto Basin. They included:

  • $1.6 million for HCFCD for Taylor Gully  stormwater channel improvement. 
  • $1.6 million for HCFCD for Kingwood  Diversion Channel improvement. 
  • $1.67 million for Harris County for the Forest Manor drainage  improvement project in Huffman.
  • $8.2 million from FEMA the Westador Basin stormwater detention project on Cypress Creek.  
  • $9.9 million from FEMA for the TC Jester storm water detention basin on Cypress Creek.

Crenshaw also has backed community requests for more funding in Fiscal 23. They include:

  • $8 million for the Lake Houston Dam Spillway (Gates).
  • $10 million for the Woodridge Stormwater Detention Basin (see below).
  • $10 million for a Cedar Bayou Stormwater Detention Basin.

Harris County Flood Control

19) Channel Maintenance and Repair

Harris County Flood Control has already completed several maintenance projects in the Lake Houston Area. In Kingwood, those projects include Taylor Gully, Ben’s Branch, parts of the Diversion Ditch and other unnamed ditches. In Atascocita, HCFCD also completed a project on Rogers Gully. Upstream, HCFCD is working on the third round of repairs to Cypress Creek. Batch 3 includes work at 12 sites on 11 channel sections. I’m sure the District has maintenance projects in other areas, too. I just can’t name them all.

Bens Branch
Bens Branch near Kingwood High School after sediment removal.
20) Woodridge Stormwater Detention Basin Expansion

In 2019, uncontrolled stormwater from the Woodridge Village development twice flooded approximately 600 homes in Elm Grove Village and North Kingwood Forest. HCFCD and the City purchased Woodridge from Perry Homes last year. HCFCD soon thereafter started removing sediment from the site to create a sixth stormwater detention basin that would more than double capacity on the site. At the end of last month, contractors had removed approximately 50,000 cubic yards out of 500,000 in the contract. This gives HCFCD a head start on excavation while engineers complete the basin’s final design.

21) Local Drainage Study Implementation

HCFCD authorized four studies of the drainage needs in the Lake Houston Area. They completed the Huffman and Kingwood studies. Atascocita and East Lake Houston/Crosby started earlier this year and are still underway.

The Kingwood study measured levels of service in all channels and outlined strategies to improve them to the 100-year level. The first two projects recommended: Taylor Gully and the Kingwood Diversion Ditch. Neither has started construction yet. But see the notes under funding above.

The Huffman Study recommended improvements to FM2100, which TxDOT will handle. It also recommended dredging in the East Fork near Luce Bayou which the City has completed. Finally, it recommended a bypass channel for Luce. However, pushback from residents forced cancellation of that project.

22) Buyouts

HCFCD completed buyouts of 80+ townhomes on Timberline and Marina Drives in Forest Cove last month. Contractors demolished the final run-down complex in August. That should improve property values in Forest Cove.

forest cove townhome demolition
Completion of demolition of one of the last Forest Cove Townhome Complexes in July 2022.
23) Regulation Harmonization

Harris County Flood Control and Engineering have been working to get municipalities and other counties throughout the region to adopt certain minimum drainage regulations. I discussed the importance of uniformly high standards in last night’s post. So far, about a third of the governments have upgraded their regs. A third are still deciding whether to act. And the remainder have taken no action. There has been little movement in the last six months.

City of Houston

As mentioned above, the City has taken a lead role in dredging, adding gates to Lake Houston, and proactive lake lowering. In addition, the City has helped with:

24) Bridge Underpass Clean-Out

The City of Houston successfully cleaned out ditches under Kingwood Drive and North Park Drive in at least six places. Bridges represent a major choke point during floods. So eliminating sediment buildups helps reduce flood risk in areas that previously flooded.

City excavation crews working to remove sediment on Bens Branch under Kingwood Drive
Excavation of Bens Branch under Kingwood Drive by City crews.
25) Storm Sewer Inspections, Clean-Out, Repairs

The City has inspected storm sewers throughout Kingwood and cleaned those that had become clogged. It also repaired sinkholes and outfalls that had become damaged.

Lone Star Groundwater Conservation District

The lowest score on the flood-mitigation report card probably goes to LSGCD.

26) Subsidence

The Lone Star Groundwater Conservation District has started pumping groundwater again at an alarming rate. Projected subsidence near the Montgomery County Border equals 3.25 feet, but only 1 foot at the Lake Houston dam. That could eventually tilt the lake back toward the Humble/Kingwood/Huffman area and reduce the margin of safety in flooding. That’s bad news.

Sand Mining Regulations

Twenty square miles of West Fork sand mines immediately upstream from I-69 have exposed a swath of floodplain once covered by trees to heavy erosion during floods. Mathematically, the potential for erosion increased 33X compared to the normal width of the river. Sand mines were also frequently observed releasing sediment into the river. And the dikes around the mines often wash out.

So in 2019, the Lake Houston Area Grassroots Flood Prevention Initiative (LHAGFPI) began meeting with legislators, regulators and the Texas Aggregate and Concrete Association (TACA). The goal: to establish comprehensive Best Management Practices (BMPs) for the sand mining industry in the San Jacinto River Basin. 

27) Mine Plan/Stabilization Reports Now Required

TCEQ adopted new regulations, effective January 6, 2022.  They required miners to file a ‘Mine Plan’ by July 6, 2022 and also a ‘Final Stabilization Report’ when a mine is played out.

28) Vegetated Buffer Zones (Setbacks)

The new regs also stipulate undisturbed vegetative buffer zones around new mines. Buffer zones aid in sediment filtration and removal by slowing surface water. They also strengthen dikes.

The new regs require a minimum 100-foot vegetated buffer zone adjacent to perennial streams greater than 20 feet in width. However, for streams less than 20 feet wide, the buffer zone is only 50 feet for perennial streams, and 35 feet for intermittent streams.

29) Reclamation Bonds

Unfortunately, the Flood Prevention Initiative could not convince TCEQ to require ‘reclamation bonds.’ Other states use such bonds to prevent miners from abandoning mines without taking steps to reduce future erosion, such as planting vegetation.  

My apologies to any projects or parties I omitted. Now it’s your turn. Give grades to those you think have done the best job on YOUR Harvey flood-mitigation report card.

Posted by Bob Rehak on 8/26/22

1823 Days since Hurricane Harvey and one day from Harvey’s Fifth Anniversary

All Parties Still Focused on Finding Solution for Adding Flood Gates to Lake Houston Dam

Initial options that the City of Houston explored for adding more flood gates to the Lake Houston Dam struggled to achieve a high enough Benefit/Cost Ratio. However, all parties involved are still hopeful that a solution can be found. They are now evaluating yet another option. It would add gates in the earthen (eastern) portion of the dam.

Looking south over eastern portion of Lake Houston Dam at area under consideration for five new tainter gates. The spillway is out of frame to the right. Picture taken on 7/22/22.

More Gates Would Create More Room For Floodwaters

Flooding devasted the entire Lake Houston Area during Harvey. Since then, Mayor Pro Tem Dave Martin has led an effort to find a way to lower the lake faster in advance of a storm. This would create extra room in the lake for floodwaters. And that would reduce the risk of flooding homes and businesses around it.

Currently, the dam has a fixed height spillway. That makes releasing water in advance of a storm difficult. The dam does have several small gates, but they have only 1/15th the release capacity of the gates on Lake Conroe. Adding more gates would help release water faster…to keep up with water coming downstream.

It would also let managers wait to start a release until they were certain a storm would not veer away. That would help avoid wasting water if forecasts are not accurate.

The Dual-Role Dilemma

The City built Lake Houston in 1953 to supply water. Making the dam play two roles – water supply and flood mitigation – poses a challenge.

In 2017, immediately after Hurricane Harvey, Martin began leading the effort to transform the dam to play a dual role. This would let Lake Houston provide our region with needed drinking water and reduce flood risk. 

New Timeline Longer Than Hoped, But Still Shorter Than Usual

A project of this magnitude normally takes up to twelve years. However, Martin worked with federal, state, and local officials to shorten the timeline. Martin now hopes the project will take no longer than seven years. While acknowledging that he hoped completion would happen in as little as five years, Martin also cites unexpected technical and cost challenges related to the aging dam.

Difficulty of Finding Best Alternative

The age of the Lake Houston Spillway, built in 1953, has proven to be a bigger obstacle than expected. Engineers initially proposed six different alternatives for adding different types of gates in different locations, with variations on several.

As engineers started precisely calculating costs and benefits of preferred approaches, they weighed those against environmental impacts, construction challenges, safety risks, and available budget.

During that process, engineers discovered hidden challenges with some options that initially looked promising. At this point, they have determined that all six initial options cost more than the federally funded amount of $48 million. 

A Complicated Path Forward

So now engineers are focusing on finding the optimal solution while Martin and others explore options to pay for it.

Martin says the City of Houston, Texas Division of Emergency Management and Federal Emergency Management Agency are working together to find the option with the highest Benefit to Cost Ratio (BCR). 

Acceptable BCRs for projects like this range from .75 to 1, according to Martin. Preliminary engineering studies found that two crest-gate alternatives (already evaluated) yielded only .48 – largely due to the aging structure of the existing spillway, which drove up costs. 

City Expects Answer on Latest Option Before October

Currently, the City has paused the final-design phase of the project while engineers evaluate Alternative 1A. That now consists of five new tainter-gates (not six or twelve as previously reported) on the earthen embankment east of the spillway. 

The comprehensive, final BCR analysis for the embankment alternative should be completed by the end of September 2022. The preliminary engineering report suggested the 1A alternative could reduce flood heights by half a foot for a cost of $47.3 million with a BCR of .89. So initially, on the surface, this appears feasible.

Martin Widens Search for Funding

While engineers work to find the best BCR, Martin is leading an effort with BOTH state and federal partners to find additional funding for the project. 

For instance, Martin is working with outgoing State Representative Dan Huberty and incoming State Representative Charles Cunningham to seek funds in the upcoming Texas Legislative Session. Martin says that state dollars do not require BCRs like federal dollars do.

While all the challenges would have discouraged many, Martin says they have fortified his resolve. He vows to find a path forward. Martin promises an update in his regular fall public meeting in October and hopes to have an attractive BCR for alternative 1A.

Interim Flood-Mitigation Measures Still In Place

In the meantime, the City of Houston will continue its existing Lake Houston pre-release strategy. It calls for lowering the lake when forecasters predict three or more inches of rain in the San Jacinto Watershed. Since Hurricane Harvey, the City has lowered the lake more than twenty times and successfully avoided flooding.

Thanks to Key Contributors 

Martin acknowledges the continuing contributions of Congressman Dan Crenshaw, Governor Greg Abbott, Lt. Governor Dan Patrick, Commissioner Tom Ramsey, State Representative Dan Huberty, State Representative-Elect Charles Cunningham, TDEM-Chief Nim Kidd, Mayor Sylvester Turner, Chief Recovery Officer Stephen Costello, and Harris County Flood Control District. 

Martin says, “All parties are committed to constructing these additional gates to help ensure protection against future flood events.”

Posted by Bob Rehak on 8/4/2022

1801 Days since Hurricane Harvey

CWA Exploring Alternate Plan for Adding Lake Houston Dam Gates

Coastal Water Authority (CWA) recently posted minutes from its May 11th board meeting that reveal a possible new direction for adding more flood gates to the Lake Houston Dam. After months of discussing various crest gate alternatives to increase the release capacity of the dam, engineers will now focus on examining two tainter gate alternatives. One would add six tainter gates, the other twelve.

Neither alternative would modify the concrete portion of the spillway, as crest gates would. Black & Veatch, the engineering firm in charge of the project, will explore adding the tainter gates in the earthen embankment to the east of the existing spillway. See below, upper right.

Looking ENE at Lake Houston Dam. Black and Veatch is now exploring adding tainter gates to the earthen portion of the dam in the upper right.

The eastern embankment is a solid earthen area 2800 feet long east of the spillway and existing gates (see upper right of photo above). Water cannot get over it in a storm because it is so much higher than the spillway. By adding various structures in this area, engineers could widen the current spillway capacity, allowing release of more stormwater.

Tainter gates rotate up from a central pivot point. Crest gates rotate down from a bottom hinge, like a piano lid.

Minutes from May CWA Board Meeting

Item IV(B) on Page 3 of the May 11, 2022, minutes states, “…CWA, City of Houston (COH), and Black and Veatch (B&V) met on April 14, 2022. During that meeting the COH requested that an alternate gate location to the east of the existing gate structure be further [emphasis added] evaluated.”

Following the meeting, B&V developed a scope of work to update the gate concepts and construction costs for this area. The COH provided comments and B&V modified its proposal. B&V reportedly began work on the new direction by June 1.

Additional Funding Needed

Each of the new alternatives would require additional funding; neither fit within the existing budget, according to the CWA staff. COH Public Works will pay for the new evaluation.

Wayne Klotz, P.E. and President of the CWA Board, reminded everyone present that COH owns the dam and is the FEMA grantee for this project, while CWA works for and takes direction from COH.

Minutes from the June CWA meeting have not yet been posted. The last post about gates on the COH District E website was almost a year ago on July 8, 2021.

7/4/22 Screen Capture from District E Website.

However, City Council member and Mayor Pro Tem Dave Martin did take questions on the project at an April 2022 community meeting. At the time, Martin expected to have a final answer on gates in a “September-ish” time frame.

Based on costs of the Addicks and Barker dam modifications by the Army Corps, some remain skeptical of any alternative for adding gates to the dam. The reason: budget and the Benefit/Cost Ratio.

Currently, the release capacity of tainter gates on the Lake Conroe Dam is 15X greater than those on the Lake Houston Dam (150,000 cubic feet per second (CFS) vs. 10,000 CFS.)

Concept Studied and Rejected Once Already

Adding gates to the eastern embankment was one of the original concepts evaluated. (See Column 5, Offsite Alternative #2, Column 5, Page 4.) But engineers focused on adding crest gates instead, largely because the total estimated costs for adding tainter gates at that time exceeded $90 million for a $50 million budget. However, the Army Corps also had environmental concerns about adding gates to the eastern embankment.

FEMA initially gave the City three years to complete the project (18 months for engineering and 18 for construction). Engineering began in April 2020.

No other details about May’s change in direction have been released to my knowledge.

Posted by Bob Rehak on 7/4/2022 based on minutes from the May CWA Board meeting

1770 Days since Hurricane Harvey

Martin Updates Community on Additional Gates for Lake Houston

Perhaps no flood-mitigation project has generated more interest in the Lake Houston Area recently than the addition of more flood gates to the Lake Houston Dam. In recent months, as engineers worked on the project’s benefit/cost ratio, information about the project became hard to find. That fueled rumors.

But Tuesday night, at the Kingwood Community Center, Mayor Pro Tem Dave Martin put many of those rumors to rest. He denied the project was on hold, reaffirmed the City’s commitment to the project, and outlined the three main issues that engineers are currently grappling with.

Issues Still Being Evaluated

The main issues include:

  • Safety concerns about cutting into the concrete of a dam that’s almost 70 years old.
  • Getting the benefit/cost ratio up.
  • Finding a suitable alternative that significantly reduces flood risk within the budget.

Martin elaborated on each. Regarding:

Safety concerns – He described the risks of cutting into it to install crest gates. Among them, he said engineers worried about structural stability of the dam after construction. Accordingly, they are recommending significant reinforcement of the concrete. He also hinted that contractors might not bid on the project for fear of the potential liability.

Benefit/Cost Ratio – He said that the higher-than-expects costs on of some alternatives drove the BCR down, and that that was driving the exploration of additional alternatives. He did say, however, that FEMA allows including “social benefits” when the BCR is between .75 and 1.0. The inclusion of social benefits still must yield a BCR of 1.0 or greater. On a separate note, a federal employee told me that the Biden administration may change this policy. So significant uncertainty still exists re: calculation of the BCR.

Budget – He implied that some alternatives under consideration became non-starters because of high costs and inflation.

Alternatives Still Under Consideration

So, the search for a suitable alternative that meets all objectives continues. Among the options still in the running, Martin mentioned crest gates on the west side of the dam and adding a tainter gate to the earthen, eastern portion.

Martin shared a timetable that shows construction beginning in November. However, FEMA must approve the benefit/cost ratio before they release construction funds.

Schedule for adding gates to Lake Houston, first shown in July 2021. Also shown on 4/19/2022. Martin emphasized the schedule has not changed, but could.

Background of Project

At the peak of Harvey, 425,000 cubic feet per second (CFS) went over the dam’s spillway. That’s five times the average flow of Niagra Falls. Floodwater backed up so far that it flooded thousands of homes and businesses. It also killed 13 people in the Lake Houston Area, 12 of them in one retirement center.

The release of 80,000 CFS from Lake Conroe contributed almost a fifth of the water going over the spillway. Lake Conroe gates can release 150,000 CFS while Lake Houston’s can release only 10,000 CFS. The disparity in release capacity caused many to ask whether more gates on Lake Houston could reduce flooding.

Martin pointed out that when water gets high enough in Lake Houston, it can escape over a 2,000-foot-wide spillway. However, more gates could play a role in a pre-release strategy.

Pre-releasing water from Lake Houston in advance of major storms, as the City does now, creates extra capacity in the lake so that it can absorb more water without flooding homes and businesses. This strategy (coupled with the seasonal lowering of Lake Conroe) has worked effectively since Harvey and prevented flooding on more than one occasion.

Time Vs. Release Capacity Vs. Water Preservation

However, right now, it takes so long to release water from Lake Houston that storms can sometimes veer away and miss us after the lowering starts. Thus, water could be wasted. But bigger gates would let dam operators release the same volume of water in less time, so operators would not have to start releasing water so far in advance. In other words they would have a higher degree of confidence that the the storm would not veer away and that release was worthwhile.

Martin reassured people that:

  • Smaller (i.e., less costly) floodgates can lower Lake Houston sufficiently if given enough time
  • The lake usually refills quickly
  • Even if it doesn’t, the City can always call for the release of water from Lake Conroe.

We should know within a few months whether Black & Veatch, the engineering company leading the project, has succeeded in designing additional gates within the budget that meet all other objectives.

Staying on the schedule above will be ambitious. FEMA must approve the BCR before releasing money for construction.

Posted by Bob Rehak on April 21, 2022

1696 Days since Hurricane Harvey