Tag Archive for: San Jacinto River Basin Master Drainage Study

After 4 Years, No Recommendations from River Basin Master Drainage Plan in Design Yet

After four years, not one of the recommendations from the San Jacinto River Basin Master Drainage Plan is in design yet.

In the summer of 2020, Harris County Flood Control District, the City of Houston, Montgomery County, and the San Jacinto River Authority released a massive study on how to address flooding in the upper San Jacinto River Basin. But four years later, not one of the 16 main recommendations has been constructed. In fact, none are even in design yet, according to one source I talked to for this post.

Cost, political willpower, eminent-domain issues, and jurisdictional boundaries seem to have torpedoed any progress.

Major Recommendations in Plan

The 3,600 page study contained 16 main recommendations.

Here’s where they are.

However, Matt Barrett, PE, the SJRA’s Flood Management Division Director, says, “No construction has started on any of the major project recommendations (detention and channelization projects).” 

Another source familiar with the plan complained that none are even in design yet. That source also cited unfavorable cost benefit ratios.

Expected Benefits of Plan

If built, these projects could make a real difference for people throughout Montgomery County and northern Harris County.

The following table shows how much the water surface elevation could be reduced in a 100-year storm at a number of locations if the recommendations were implemented.

From Page 27 of Executive Summary

Cost Issue

The 2020 study estimated that building all these projects could cost up to $3.3 billion. They would cost more today. We’ve had 20% inflation since then.

The total in today’s dollars could easily approach $4 billion. That’s a pretty major ask for taxpayers.

But the 2018 Harris County Flood Bond (approved before the study) included only $18.75 million dollars for “Funding for Future Partnership Projects Based on Results of Study – for Right-of-Way Acquisition, Design, and Construction of General Drainage Improvements in San Jacinto River Watershed Study.” See Project C-50.

Political Willpower

Funding for the gap will not come from any of the study sponsors.

Harris County Commissioners Court has prioritized “equity” projects in low-to-moderate income areas inside the Beltway. Some have even declared they will never vote for spending money outside of Harris County.

Most of the projects are outside the City of Houston and its extra-territorial jurisdiction.

The San Jacinto River Authority doesn’t have an income stream to fund the improvements.

And most Montgomery County Commissioners don’t see flooding as their most pressing problem.

Understandably, no one has seized the reins for these projects. Even if physically feasible, they don’t seem politically feasible at this point.

Eminent Domain and Jurisdictional Boundaries

Worse, 10 of the 16 projects are large stormwater detention areas that would likely require invoking eminent domain. That’s always politically dicey for politicians. Especially when the major benefits would accrue to downstream residents outside of their precincts – and even outside of their own county.

Better Lake Conroe Management Not Enough

As this multi-million study has been consigned to dusty bookshelves, flood-weary residents have increasingly pinned their hopes on better management of the Lake Conroe dam.

Seasonal lowering of Lake Conroe has morphed into “Active Storm Management,” a compromise between upstream and downstream interests on the San Jacinto West Fork. Instead of lowering the lake for set amounts for set periods of time each year, dam operators are now trying to lower it temporarily on the fly in advance of approaching storms. But that presents its own set of problems.

It also doesn’t affect water funneling in from other watersheds. The Lake Conroe watershed comprises only 13% of the Lake Houston watershed. That means rain falling over 87% of the area upstream from Lake Houston has nothing to slow it down.

Lake Houston Gates Not Enough Either

Farther downstream, the City of Houston has been designing new gates for the Lake Houston Dam. They will help lower floods in the Lake Houston Area somewhat. But they won’t help people upstream. And they have run into one problem after another.

For instance, the City could not find any contractors willing to bid on the recommended alternative – building crest gates on the 70-year old spillway. It was just too risky. So, the City is now redesigning the entire project.

Just three years ago, the project was scheduled for completion this summer. But the timetable has been delayed at least another four years.

Time to Reboot the Master Drainage Plan: But How?

So what can we do to refocus attention and gain momentum behind the projects in the San Jacinto River Basin Master Drainage Plan?

In my opinion, we need to see the state take over execution of the plan. There are just too many conflicting interests at the local level.

We need to make one person/entity responsible for executing the plan.

Bob Rehak

The logical choice would be someone at the Texas Water Development Board. It’s assembling a state flood plan that includes the San Jacinto River Basin.

So how do we make that happen? We need to engage our state leaders.

Posted by Bob Rehak on 6/26/24

2493 Days since Hurricane Harvey

The thoughts expressed in this post represent opinions on matters of public concern and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statute of the Great State of Texas.

SJRA Seeks Public Input on Sediment Trap Proposal

The San Jacinto River Authority (SJRA) recently completed a 246-page conceptual design study, in partnership with the Harris County Flood Control District, that explored the feasibility of implementing sediment trapping facilities (“sand traps”). The purpose: to remove sediment from the West or East Fork of the San Jacinto River. The results and findings of this study have been documented in an engineering report entitled “San Jacinto River and Tributaries Sediment Removal and Sand Trap Development.” 

Prior to proceeding to preliminary engineering design and any subsequent project phases, SJRA is seeking public input on the proposed project alternatives detailed in the report. The full report, as well as a brief summary document, are located on SJRA’s Flood Management Division website. 

How to Provide Input or Ask Questions

Please submit input and questions via email to floodmanagementdivision@sjra.net. 

Deadline: No later than April 29, 2022

Caution: The full study is dated 1/7/22. But the “brief summary” is dated 3/9/22. Make sure you at least read the executive study of the full report as well as the brief summary. There are important differences.

Overview/Purpose

SJRA says the purpose of the sediment trap study was to assess the feasibility of implementing a pilot project to trap and remove sediment from the West OR East Fork of the San Jacinto. The study only assessed locations where one or more Aggregate Production Operations (APOs) could partner with the the SJRA. They restricted the study this way to reduce costs; the SJRA does not have a source of funding to clean out sand traps and would rely on sand miners.

Initial Concerns

The decisions to:

  • Define the study objective as sediment reduction, not damage reduction and…
  • Only consider locations near sand mines…

…give me mixed emotions about this project.

Pros

On one hand, I look at this and say, “It’s a pilot project. Try it and see if there’s a benefit.” Sediment IS a problem and they believe they can remove up to 100% of the annual sediment load (from the West Fork).

Cons

On the other hand, the study authors, Freese & Nichols (F&N) claimed (in the San Jacinto River Basin Master Drainage Study) that of all the sediment coming into Lake Houston, two thirds comes from Spring and Cypress Creeks while only 13% comes from the West Fork upstream of US59.

Perhaps that’s because they’re using model inputs from a sediment gage at I-45 located 8.5 miles upstream from most of the large West Fork sand mines (page 34, paragraph 3 of full study).

Also, in their discussion of downstream sedimentation mitigation (page 51, paragraph 3 of full study), F&N says that their evaluation was confined to areas where natural processes rather than breeches of sand mine ponds likely contributed to sediment deposition. To see how limiting that is, see the photos of sand mine breeches and their results in this post.

West Fork Mouth Bar
The “Mouth Bar,” a giant sand bar that blocked the West Fork of the San Jacinto, backing the river up into Kingwood and Humble. Thousands of homes and businesses flooded behind this blockage. The above-water portion has since been removed, but most of the underwater portion remains.

In the entire 246-page F&N study and the three-page summary, the word “damage” occurs only once…in relation to erosion damage, NOT flood damage.

It appears that F&N did not even look at creating sand traps where they were most needed, in the headwaters of Lake Houston, because of cost and logistical considerations. Yet the Army Corps, City of Houston, and State of Texas are spending $200 million to dredge that area. One wonders whether SJRA should have looked harder for partners to clean out the traps.

Finally, if sediment traps only work financially near sand mines, the “solution” will not work on other tributaries that F&N alleges contribute 5X more sediment than the West Fork. They just don’t have the sand mines that the West Fork has.

Nature of Proposed Solution

Five years after Harvey, we have a conceptual design and a recommended location: rock-lined channels cut through one or two point bars at the West Fork Hallett mine.

Page 8 of the F&N study shows this schematic of the recommended solution.

The shot below shows the same area in real life. To put the magnitude of the proposed solution into perspective, the solution would cover a little more than an acre. But sand mines like Hallett cover 20 square miles on the banks of the West Fork between US59 and I-45.

2021 photo of sand bar outsde Hallett mine that would have a narrow channel cut through it to trap sand.

My Biggest Fears

My biggest fears with the proposed pilot study are that it:

  1. Asks people to chose from a limited menu.
  2. Could divert attention from better solutions that would reduce flood risk faster in the headwaters of Lake Houston.
  3. Might make the public think the problem is solved.
  4. Could open the door to river mining and further destabilize the riverine environment.
  5. Is not a transferrable solution.

For a pilot study, that last point is troubling.

Also, F&N worries that removing too much sediment from the West Fork could create a “hungry-water” effect that increases erosion downstream. But they have no way of directly measuring how much sediment the West Fork transports. Or what percentage they would remove. That’s because they’re relying on a sediment gage upstream from the sand mines. This introduces an element of risk in the pilot study.

Recommendations Should Be Based on a Holistic Examination of Alternatives

Note lack of vegetation on this steep-sided, eroding bank of Hallett mine on West Fork in foreground.

Before moving forward with the pilot study, I suggest a more holistic examination of additional alternatives that might have a greater impact on reducing flood damage, not just sedimentation. Examples include, but are not limited to:

More on the sand trap proposal in coming days. In the meantime, please review the SJRA’s sediment trap proposal and forward your comments to the SJRA. I will also print thoughtful letters, both pro and con, from responsible parties. Send them to: https://reduceflooding.com/contact-us/.

Posted by Bob Rehak on March 27, 2022

1671 Days since Hurricane Harvey

The thoughts expressed in this post represent opinions on matters of public concern and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statute of the Great State of Texas.