The San Jacinto River Authority (SJRA), which is managing a feasibility study on two Spring Creek dams, has run into some unexpected hurdles. They involve the benefit-cost ratio and competing uses for the land. Matt Barrett, PE, the SJRA’s Water Resources and Flood Management Division Manager, updated ReduceFlooding on the status of the project.

Project Location Near Montgomery

Harris County Flood Control District, five municipal utility districts, the City of Humble, and the Texas Water Development board are also involved in this project. The dams could reportedly reduce flood levels up to half a foot for 40 miles downstream.

Second Time Around for Spring Creek Dams

The SJRA first recognized the flood mitigation benefits of dams in the Spring Creek watershed back in 1985. But ironically, while the land could have been bought for a song back then, the projects failed to achieve favorable benefit-cost ratios because so few people lived in the then-rural area.

Fast forward 32 years to Hurricane Harvey when more than 10,000 structures downstream flooded. Experts identified more upstream stormwater-detention as one of the top three priorities for flood mitigation.

When I asked Matt Barrett, PE, the SJRA’s Water Resources and Flood Management Division Manager about the status of the dams, he had this to say. “We’re still working on the feasibility study. We ran into a couple hurdles when we started digging further into the proposed reservoirs.”

Benefit-Cost Ratio

What kind of hurdles? “First, after modeling was updated as part of the study, the benefit/cost ratios came out lower than was previously estimated as part of the San Jacinto Regional Watershed Master Drainage Plan,” said Barrett.

“I think we have a solution for this issue,” he said. “Once we optimized dam sizes and incorporated ‘social benefits’ (which the Federal Government now will consider) into the calculations, the BCRs came out at 1.88 and 2.03 for the two reservoirs.” That means the benefits exceed the costs, a crucial hurdle.

“Because of their costs, the reservoirs would almost certainly rely on some level of Federal participation for construction.”

Matt Barrett, PE

Competing Uses for Land

“The other issue,” Barrett continued, “is that each planned reservoir site is also the site of another planned development, which was not identified until we got into the feasibility study.”

A residential/commercial development is planned for the Birch Creek reservoir site, and a large solar farm for the Walnut Creek site.

Barrett said, “No ground has been broken on the former, and I would like to work with the developers to see if we can come up with a scenario where both projects could exist. Construction HAS begun at the solar farm site, and we are coordinating to determine what options there might be for future coexistence at the site.” 

Funding Partners Will Determine Path Forward, Timetable

“We are currently scheduling meetings with elected officials to present the project and its challenges,” said Barrett. “We want to get their input. Our goal is to get back together with our funding partners likely early next month to determine our path forward.

“The draft report should be completed by April next year, but that is subject to change.  We are behind schedule due to the challenges experienced.”

Project Will Ultimately Depend on Several Factors

Barrett concluded, “Whether the reservoirs ultimately get built will be based on the results of the study and whether there is an entity willing to champion the project through design and construction and ultimately own and take responsibility for operations and maintenance of one or both reservoirs.”

Alternative Possibilities

The SJRA is not actively looking at alternative reservoir sites. However, SJRA and its partners have discussed it. “If we determine the hurdles at the two proposed sites make those sites infeasible, we could consider other sites,” said Barrett. “That said, we selected those two sites because they seemed the most promising. Other sites may not pan out for other reasons. One potential alternative is to look at several smaller detention sites.”

For More Information

See these previous posts on the projects:

• Original 1985 SJRA study
• TWDB grant application
• Harris County approves new feasibility study
• Region 6 Flood Planning Group Draft Recommendations
• Updates of three SJRA studies

Posted by Bob Rehak on 9/15/2023

2208 Days since Hurricane Harvey