3/31/25 – In the first two parts of this “Wastelands to Wetlands” series, I presented a vision for restoration of the San Jacinto West Fork and listed all the various parties who have an interest in the effort and could help. But how do you coordinate them? Who would take responsibility/authority for ensuring restoration? And how would you measure their success? That is the focus of this post.
My purpose is to start a dialogue that gets people moving in the direction of a solution. I don’t claim to have all the answers. Nor do I believe that this is the only way to get to a solution.
Need for Leader to Guide Restoration
Right now, no group or leader exists for such an effort. But restoration will never happen unless someone takes the initiative (or has the responsibility) to turn ideas into action.
In business, I learned that if you put two people in charge of a project, no one is in charge. Right now, we have more than a dozen groups theoretically in charge of permitting various aspects of restoration. But none is in charge of oversight and coordination. That’s a problem.
Do We Use Existing Group or Start New One?
Several contenders for the job already exist. But do they have the knowledge, skills, funding and desire to take on the additional work?
The San Jacinto River Authority (SJRA) theoretically has the authority. And they have established a flood management division. But do they have the desire to take on the environmental restoration job? They architected a massive Master Drainage Plan for the entire river basin. But after more than four years, they have yet to implement one recommendation from it. SJRA seems focused on capturing water in Lake Conroe and selling it.
Further downstream, the Coastal Water Authority has the responsibility for managing Lake Houston. But no one has given them responsibility for fixing upstream issues between the two lakes that pollute their water.
Unless one of these two groups accepts restoration as a mission and dedicates the resources to achieving it, we need to create another authority responsible for the area between Lake Conroe and Lake Houston – a West Fork Restoration Authority.
Mission Defined
Their mission: turn wastelands into wetlands. How? 1) Restore abandoned mines using a combination of grants and matching funds dedicated to the effort by the state legislature. 2) Monitor active mines to ensure they comply with their abandonment plans when the time comes. 3) Coordinate the efforts of all affected parties to ensure they are additive and contribute to the long-range plan over time.
Creating such an authority would require action by the state legislature in 2027. It’s too late for this session.
Board Structure
A board appointed by the governor and affected parties, such as the City of Houston, Montgomery County, the mining industry, and residents, could manage the West Fork Restoration Authority.
Suggested Success Metrics
How would they measure success? Here’s a list of major needs, metrics, and milestones.
A) Completion of business plan
B) Acquisition of staff
C) Completion of engineering study
D) Design of solution and component parts
E) Costs estimates
F) Publication of long-term plan with stages/tasks outlined
G) Successful grant applications, funds raised
H) Permits obtained
I) Acres revegetated
J) Linear feet of trails installed
K) Reduction of erosion
L) Water-quality improvements
M) Publication of quarterly and annual progress reports
N) Creation of case study that communicates knowledge gained to guide similar efforts elsewhere
Time Limited
The State’s Sunset Commission would review the Restoration Authority at regular intervals (currently 12 years) and dissolve it after completion of its job or for lack of progress.
Need
Do we need such an Authority? In my opinion, YES! The economic future of the region depends on eliminating the blight that contributes to flooding. The West Fork has:
Approximately 20 square miles of sand mines, many abandoned, between Lake Houston and I-45
Become completely blocked in some areas
Broken through the dikes of at least five sand mines.
Hallett Mine on West Fork. Picture taken March 19, 2025.Pit in foreground has been captured by river, cutting off normal channel to right.
We need the area’s elected leaders to work together to restore the West Fork as mines like the one above play out and the miners move on to other areas.
We need their help in turning Wastelands into Wetlands. Otherwise, the next generation will be stuck with the situation below.
Confluence of Spring Creek (left) and West Fork (right) with its 20 square miles of sand mines. Photo taken in January 2025
Posted by Bob Rehak on 3/31/25
2771 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2025/03/20250319-DJI_20250319102634_0380_D.jpg?fit=1100%2C619&ssl=16191100adminadmin2025-03-31 15:26:012025-03-31 15:27:27Wastelands to Wetlands, Part III: Turning Ideas into Action
11/30/24 – On November 26, 2024, the Court of Appeals for the First District of Texas dismissed homeowners’ claims in the long-running SJRA Takings Case. The case arose from Hurricane Harvey flood damage.
Downstream homeowners alleged that San Jacinto River Authority (SJRA) releases from Lake Conroe significantly exacerbated their flooding. The resulting damage, they claimed, amounted to an illegal taking of their property by the government.
The Texas Constitution provides that “no person’s property shall be taken, damaged, or destroyed for or applied to public use without adequate compensation.” (Texas Constitution, Article I, Par. 17(a)).
Sadly, the alleged “facts” cited in the Appellate Court’s ruling apparently went unchallenged. And some of those so-called facts may mislead.
Speed of Floodwaters a Major Deciding Factor
The appellate court judges based much of their ruling on an argument related to the speed of floodwaters.
SJRA had produced an expert report by Mark E. Forest. The appellate judges said on page 24 of their ruling that “…the timing [emphasis added] of the water releases and flooding supported the conclusion that the River Authority’s water releases did not cause the homeowner’s flooding.”
The judges continued, “Forest explained that the water from Lake Conroe would take about 30 hours to travel the 38 miles downstream to reach the Humble and Kingwood areas, where most of the homeowners’ properties were located.”
Then, on the same page, comes this pivotal sentence. The judges say,
“About 30 hours after the River Authority first released water from Lake Conroe, the Humble and Kingwood areas had already experienced ‘major flooding,’ as the river levels had already risen from 41 feet above sea level to 62 feet.”
Then the coup de grâce. “This major flooding occurred ‘without any contribution from Lake Conroe since those contributions had not yet arrived’ Forest explained.”
The appellate judges in the SJRA Takings Case evidently bought that argument. At the bottom of Page 24, they said, “Therefore, the River Authority produced evidence that its water releases from Lake Conroe did not cause or exacerbate the flooding of the homeowners’ properties.”
In their conclusion on page 36, the judges also state, “The homeowners’ evidence does not raise a fact issue to refute the River Authority’s evidence. The homeowners have not met their burden to provide evidence showing there is a material fact issue as to the causation of their inverse condemnation claim.”
Basis for SJRA Speed Estimate Unclear
I have asked SJRA repeatedly how they arrived at 30 hours and never gotten an answer. That made me suspicious. The SJRA claims floodwaters move only1.27 MPH (38 miles in 30 hours). An average person can walk 3-4 miles per hour!
Plus, I’ve measured (with my drone) logs floating downriver in lesser floods at 5-6 MPH.
The speed of floodwaters determine their arrival time downstream. Claiming a 30 hour travel time that easily could have been as brief as five or six hours could cause people to focus on the wrong part of the flooding bell curve. And it appears that may be what happened in this case.
Judges Cite Flooding at Less-Than-50-Year Level
I’m not sure what data Forest cited; the judges don’t specify. But let’s assume it came from the gage at the West Fork and US59.
Importance of Speed in Determining Proximate Cause
If you assume a higher rate of speed and correlate that to when floodwaters reached the 100-year level where most homes begin to flood, it’s easier to see a possible connection between the Lake Conroe release and structural flooding downstream.
Floodwaters traveling 5-6 MPH would reach US59 in five to six hours, not 30 hours.
According to the Harris County Flood Warning System, the West Fork reached a 100-year-flood level at US59 at 8:42 PM on 8/28/2017.
And according to an SJRA affidavit supplied during the original trial:
30 hours earlier, SJRA was releasing 10,946 CFS.
6 hours earlier, SJRA released 78,885 CFS.
So, between the 30 hours claimed by the SJRA and the six hours indicated by drone measurement, the SJRA increased its release rate by almost 8X.
If the drone measurements are accurate and representative…
SJRA releases increased dramatically shortly before structures near US59 flooded.
This suggests a different conclusion. SJRA releases may have been a far more proximate cause of downstream flooding than SJRA-supplied data implied.
Would homes and businesses have flooded eventually anyway? Certainly, that’s true for some. But it might not be true for others.
No one would expect a home to flood in Kingwood when you release 11,000 CFS from Lake Conroe.
But how about an additional 79,000 CFS when homes were already on the verge of flooding? That’s a very different story – especially considering that at the peak, Lake Conroe releases comprised one third of the total water coming down the West Fork. Many homes at the periphery of the flooding might have stayed dry had the timing and volume of releases been different.
Too Late Now
The plaintiffs’ expert consultant in the SJRA Takings Case did not conduct his own hydrological modeling (Page 26). That’s unfortunate.
Even if the plaintiffs in this case succeed in getting the Texas Supreme Court to hear an appeal, additional evidence would likely be inadmissible.
In general, appellate courts do not consider new evidence. Their primary role is to review the record from lower courts to determine whether legal errors were made that significantly affected the outcome of the case. Appellate courts focus on issues of law rather than fact.
Posted by Bob Rehak on 11/29/24
2650 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.
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For everyone else, I’ve posted a brief summary below. It covers key provisions, including those that affect lake lowering to help reduce flood risk. Spoiler alert: I made a startling discovery at the end of the contract doc.
But let’s start from the top of the Lake Conroe contract.
Key Definition
The first few pages lay out the customary recitals and definitions found in all contracts. The key definition is that of a 1987 Certificate of Adjudication (Number 10-4963, shown in Appendix A) that governs the impoundment, use, diversion, and priorities of water in Lake Conroe.
Ownership Interests
The meat of the contract starts in Article II on page 5: Interests of the Parties. Key points:
SJRA owns the land that constitutes the Lake.
The City owns two-thirds of the water in it.
SJRA owns the remaining one-third.
Each party has the right to sell its share of the water.
Other revenues from the operation of Lake Conroe, such as income from marina leases, go toward operating and maintaining the lake.
Operational Responsibilities
Article III on Page 6 of the Lake Conroe contract lays out operational responsibilities.
SJRA:
Operates and maintains the lake and dam.
Handles all the accounting and reporting for water impounded and released.
Maintains metering devices and monitors withdrawals (must be accurate within ±5% or better)
Lets lakefront homeowners pump water directly from the lake for $150/year to water their lawns
Joint Responsibilities:
Annual reports to public and TCEQ of withdrawals.
Annual withdrawals by their respective customers.
Release of Water and Reservoir Levels (Section 3.04, )age 8)
SJRA must release water when requested by City (subject to restrictions in the Certificate). But it must do so in a way that maximizes the operational yield of the lake.
Liability and Indemnification (Section 3.05, Page 9)
Both parties are jointly liable for damages when the lake is operated according to established procedures.
If one side is negligent, that party assumes sole responsibility for any damages.
Other sections in Article III cover:
Defense of claims
Regulatory compliance
Water Quality
Annual budget and what happens if City Council fails to approve the annual budget
Monthly payments by the City to SJRA for capital, operations and maintenance expenses
Flood mitigation (Section 3.16 (c), Page 17)
Reports and Inspections; Incidental Matters
Article IV, starting on Page 17 covers:
Annual audits
Inspection of records
Disposal of surplus property
Length of Contract
This contract replaces the original 1968 Lake Conroe contract between the City and SJRA. It will remain in effect until terminated by mutual agreement during the useful life of Lake Conroe.
Default and Notice; Remedies; Mediation
Article V covers how the parties will handle disputes. It starts on page 18 and goes through page 23. Basically, it covers procedures leading up to mediation in the event of disagreements.
Force Majeure
Article VII covers force-majeure events. In law, “Force Majeure” means “unforeseeable circumstances that prevent someone from fulfilling a contract.” This section defines what happens during Acts of God, such as hurricanes, storms, floods, droughts, etc.
This Article allows the temporary suspension of normal rules, except those regarding payments. However, it requires resumption of the normal rules after the event.
Other Provisions
Article VIII contains addresses and contact information for each party and approval procedures.
Article IX includes provisions concerning applicable law (State of Texas), procedures for amendments, etc.
Exhibit A
The Certificate of Adjudication from the Texas Water Commission, dated February 25, 1987, limits total withdrawals from Lake Conroe to 100,000 acre feet per year. It lists the maximum withdrawal rate as 700 cubic feet per second.
Note: Some at the SJRA and City have chafed at this limitation. It restricts pre-release rates that could lower Lake Conroe in advance of approaching storms. Some want to raise the limit so that more water could be released earlier and reduce flood peaks.
The TCEQ amended the Certificate in 2010. It keeps the total withdrawals and max withdrawal rate above constant. But it added an additional use for the water. To the original municipal, industrial and mining categories, they added agriculture. It says they did that because they had not received any complaints about the previous limits within each category.
This is, in essence, a permit to release/sell water. And the permit comes with an obligation – to implement water conservation plans, which the TCEQ letter also spells out.
Exhibit B
This 2016 letter from SJRA’s management to the City explains a residential-lawn-watering permit program for lakefront homeowners. The program lets them pump water directly from the lake for a permit fee of $150 per year (as of 2016). That’s 41 cents per day.
They saved the best part for last. This was a real eye opener.
The permits mandate a “drought contingency plan” that impose watering restrictions when the level of the lake gets to 199 feet above mean sea level. Astute readers may remember that SJRA’s seasonal lake lowering plan took the lake down to 199 for large parts of the year.
Editorial Comment
Hmmmmm. Could that be why the Lake Conroe Association (LCA) fought seasonal lake lowering so vigorously?
People protesting the seasonal lake lowering policy wore red shirts saying “Stop the Drop,” and packed SJRA board meetings.
We may never know with certainty whether the loss of lawn watering was the sole or a contributing reason. But either way, unlimited watering of giant lawns for only 41 cents per day certainly helps explain at least some of the pushback from the LCA.
Posted by Bob Rehak on 8/21/24
2549 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.
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The San Jacinto River Authority and City of Houston have abandoned their automatic “seasonal” lake lowering policy. The seasonal program lowered Lake Conroe automatically to fixed levels during the rainiest parts of the year (April/May and August/September, i.e., the peak of hurricane season).
They have replaced seasonal lowering with a new program called “active storm management” that gives the City and Lake Conroe dam operators more flexibility to respond to actual weather conditions.
Basically, they can keep water levels up when no storms are expected. But they can lower the lake in advance of major rain…any time of the year…by amounts that will keep the lake level as stable as possible and downstream residents as safe as possible.
It’s a compromise that can be summed up in the words “as needed vs. automatic.”
Below, you can see the exact wording of the new protocols. Below that, you can see my simplified summary/interpretation. I also provide a link to the actual contract between the City and SJRA.
Active Storm Management Protocols for Lake Conroe and Lake Houston – 2024
Spring
Beginning April 1 through June 1, the City of Houston may request diversions to lower Lake Conroe from normal pool of 201’ msl to create up to six inches of storage capacity for forecasted storm event inflows (to 200.5’ msl). The decision of when, how, and whether to initiate diversions will be guided by climate conditions, weather patterns, and available water supply.
Resume normal recapturing after each storm event that triggered any diversion between April 1 and June 1.
In the event a major rainfall is forecasted to impact our region, active storm management protocols of the City of Houston could initiate a diversion to create up to an additional six inches of storage capacity for storm inflows (to 200.0’ msl). It is acknowledged that under extraordinary weather circumstances, additional diversions to create capacity below 200.0’ msl could occur.
Fall
Beginning August 1 through October 1, the City of Houston may request diversions to lower Lake Conroe if actual lake levels are at normal pool of 201 msl to create up to six inches of storage capacity for storm inflows (to 200.5’ msl). After Labor Day, storage capacity may be increased an additional six inches (to 200.0’ msl). Diversion volumes requested to reach intended levels will be dependent on the actual lake levels. The decision of when, how, and whether to initiate diversions will be guided by climate conditions, weather patterns, and available water supply.
Resume normal recapturing after each storm event that triggered any diversion between August 1 and October 1.
If a named storm is predicted to impact our region, active storm management protocols of the City of Houston could initiate a diversion to create up to an additional six inches of storage capacity for storm inflows (to 199.5’ msl). It is acknowledged that under extraordinary weather circumstances, additional diversions to create capacity below 199.5’ msl could occur.
Protocol – Lake Houston
Year Round
City of Houston will initiate releases to lower Lake Houston prior to major rainfall events.
Conservation Pool Elevation is 42.4’ msl.
Lake Houston level reduced to 41.4’ msl if a 24-hour rainfall forecast of 3 inches or more is expected. within the Lake Houston watershed.
Under extraordinary weather circumstances, Lake Houston level may be reduced below 41.4’.
Duration
The Protocols above will extend to the end of 2024 but will be reviewed by the stakeholders in October/November of 2024. During the review, the stakeholders will discuss strategies that extend beyond 2024.
Advocacy and Education
All stakeholders will work to support flood mitigation projects and efforts across the upper watershed, including improvement of land use regulations to reduce runoff from new development in counties that contribute flow to Lake Houston.
Because public education regarding completed and ongoing downstream mitigation efforts is critical to generating upstream support for continued active storm management at Lake Conroe, all stakeholders agree to educate their constituents regarding: active storm management protocols being implemented at Lake Houston, completed and ongoing sediment removal projects in the San Jacinto River basin and Lake Houston, and continued progress on the Lake Houston spillway modifications.
Because of its impact on effective active storm management, all stakeholders will support City of Houston and SJRA efforts to amend the Certificate of Adjudication for Lake Conroe to increase the maximum diversion rate.
All stakeholders agree to support efforts to limit further construction of habitable structures around Lake Conroe below elevation 207’ msl.
Important Notes
All water released from Lake Conroe as part of active storm management is being accounted for from the City of Houston’s 2/3 share and reported to TCEQ by the City of Houston. Therefore, all final decisions on diversions are ultimately the City’s and must be communicated to the SJRA in writing. This includes defining active storm management protocols.
All flood mitigation protocols could be limited due to drought conditions.
Rehak’s Summary
Note the words “MAY REQUEST” in the first sentences under Spring and Fall. Lowering is now on an “as needed” basis, not automatic.
Note also the words “RESUME NORMAL RECAPTURING” in the second bullet points under Spring and Fall. Operators will attempt to return the lake to its normal level after the storm threat has passed. The lake will not automatically be kept lower for the rest of the season.
All stakeholders have agreed to review the policy at the end of this year and modify it as necessary.
All stakeholders have also agreed to support mitigation projects including:
Land use regulations that reduce runoff
Education of residents re:
Active storm management protocols at Lake Houston
Construction progress of more Lake Houston gates
Sediment removal projects
An increase in the maximum pre-release rate for Lake Conroe
Limiting future construction around Lake Conroe to a safe level (207 feet above sea level).
The City of Houston must initiate lake lowering IN WRITING.
Water released from Lake Conroe at the City’s request will be reported to the TCEQ.
The City makes all decisions on releases.
Its decisions are final.
The City may redefine “active storm management” protocols, but should consider drought conditions when making decisions.
Decisions to Lower Lake Outside of Spring/Fall Dates
However, during the April SJRA Board meeting at which Active Storm Management was approved unanimously, the official minutes note that all parties agreed that the City could order the release of water from Lake Conroe at any time – regardless of the season.
For ease of future reference, you can also find the details above on this site’s Lake Lowering page.
Posted by Bob Rehak on 6/25/24
2492 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2024/06/Release-Water-Any-Time.png?fit=2832%2C806&ssl=18062832adminadmin2024-06-25 11:14:472024-06-25 12:24:10“Seasonal” Lake Lowering Out. “Active Storm Management” In.
5/24/24 – The SJRA board reviewed a presentation yesterday about Lake Conroe release rates during the early May storm this year. Sadly, while some people flooded, far fewer flooded than in Harvey, despite the fact that the peak inflow to Lake Conroe was higher during this storm than it was in Harvey.
Better management of the temporary floodwater storage space between Lake Conroe’s normal lake level and flowage easement may have made the difference. But there may be opportunities to make an even bigger difference.
Dissecting a Disaster
In early May this year, the headwaters of Lake Conroe received half a year’s rainfall in a few days. It was extreme to say the least. At the peak of the inflow, dam operators were releasing almost 72,000 cubic feet per second, yet the lake level still rose.
That was the second highest release rate in the history of the San Jacinto River Authority (SJRA). Only during Hurricane Harvey did the SJRA release more – 79,000 CFS at the peak.
The peak inflow was greater during this event than during Hurricane Harvey, according to Bret Raley, the San Jacinto River Authority’s Lake Conroe Division Manager.
This time, hundreds of homes flooded downstream. Thousands more were threatened. But it wasn’t nearly the disaster that Harvey was.
Regardless people who flooded or nearly flooded want to know why the release rate was so high and whether it could have been lower. Raley’s after-action report to the SJRA board meeting yesterday provides some answers.
Or you can review the slides below and my summary.
Note: some slides in this presentation use slightly different time periods.
Temporary Storage Provides Partial Buffer Against Flooding
Raley began with a recitation of SJRA’s top priorities re: operation of the Lake Conroe Dam.
He stated that “Our number one priority is … to preserve and protect the structural integrity of the dam. If we did not, the ramifications would be unimaginable.”
“I contend we are protecting public safety. How? Through a vigorous inspection and maintenance program; post-event assessments; and safe spillway operations.”
The dam, he says, provides a buffer against the full brunt of floodwaters. You’ll see later in the presentation, that at times, the inflow exceeded the outflow. Even though the Lake Conroe dam wasn’t designed for flood control, it still provides a modest buffer of temporary storage that helped reduce downstream impacts.
Only 15% of Upper Basin Protected by Dam
The Lake Conroe dam controls only about 15% of the square mileage in the upper San Jacinto River Basin.
The upper San Jacinto River basin includes nine different watersheds that all drain to Lake Houston. Said Raley, “Ours is at the very, very top of what I sometimes refer to as a funnel. Tthe bottom of the funnel is Lake Houston, the Lake Conroe watershed is at the top.”
Raley continued, “The Lake Conroe watershed is only 450 square miles. But it’s also the only watershed in the entire 3000 square miles controlled by a gated structure. The other nine watersheds flow through seven different counties.”
When rain makes its way to Lake Houston depends on when and where the rain fell. In this event, the heaviest rain fell in the West Fork (Lake Conroe) and East Fork watersheds. It could have been much worse if heavy rains had also fallen in Lake, Spring, and Cypress Creek watersheds.
Permit Limits Storage Higher Than 201 Feet Above Sea Level
The Lake Conroe Dam’s operating permit imposes several limitations that operators must contend with.
Said Raley. “The dam was constructed pursuant to a permit from the State of Texas. It authorizes us to store up to an elevation of 201 feet above mean sea level permanently. We also have the authorization to store above 201 temporarily during storm flows.”
“The permit also requires us to pass the inflows once the lake level gets above 201. But any water released below 201 must be used against permitted water rights. So there must be a permittee with available water, and then that permittee can ask to use the water.”
“The City of Houston may have, from time to time, water that’s available, and if so, they can call on it.”
Storage, Mitigation and Pre-Release
Raley then discussed the three main things he wanted people to remember from his presentation. He summarizes them in this slide.
Raley says that water which rises above 201 feet above mean sea level (MSL) cannot be held back; the lake’s operation procedures mitigate peak downstream flows; and that if the City of Houston wants to lower Lake Conroe, the City must ask for the water out of the two thirds of the lake that it owns.
Raley never addressed why the SJRA discontinued its seasonal lowering program that was in effect for several years after Harvey. The existence of that program contradicted some of the points he made in his presentation. That leads one to wonder how firm the rules he describes really are in emergencies.
Water Must Be Released as it Starts to Rise
After introducing his key points, Raley goes into more detail on each.
Raley discussed the differences between water-supply and flood-control reservoirs. “Lake Conroe is a water supply reservoir,” he said. “The intent is to keep the reservoir as full as possible to maintain your supply. In a flood control reservoir, you want to maintain capacity. You want to maintain space that can accept inflows so that you can absorb that water before having to pass it.”
Normally, Only 18″ Between Top of Water and Top of Gates
The design of the tainter gaits on Lake Conroe is another constraint. They do not allow much room for water to rise.
The photo on the left shows a gate in the normal resting position with the lake at the normal level. Water can rise only 18 inches before overtopping the gate.
If that happens, operators lose control. So, as the water rises, they must elevate the gate to stay ahead of rising levels. Remember, storms often pack high winds that create waves. Water can be choppy, not placid as shown here.
“Our gates are not designed to be overtopped” said Raley. “So, we must raise them incrementally to maintain safe freeboard.” Freeboard is an engineering term that, in this context, means “safety margin.”
The second photo shows the downstream side of a gate. Sheet flow coming over the top could destroy this support structure says Raley. “They’re just not designed to withstand that kind of force.”
Six Feet of Buffer Space
A flowage easement lets the SJRA flood properties surrounding Lake Conroe during extreme events. “We’ve got six feet of buffer that we can use,” said Raley. “Our operating protocol helps balance lake-level rise upstream and outflows downstream.”
As the water in the lake rises, SJRA must raise the gates. Still, rising water indicates that more water is coming in than going out…at least temporarily.
In extreme events, SJRA could certainly use even more stormwater storage. (But that would require pre-releasing water. Raley describes the constraints on pre-release several slides further down.)
Areas north and east of Lake Conroe received about half a year’s rain in a few days, testing the limits of the system that Raley described. It wasn’t just the amount of rain. It was also the intensity.
The basin wide average for May 2nd, for instance, approached 7 inches.
The lake at at FM1375 received more than an inch (or close to) it in several 15-minute periods. At that same location, they also received three inches in one hour.
It’s also important to realize that SJRA came into this event coming off another heavy rain. Note how the solid black line below (at the left) was just starting to return to normal when it suddenly peaked.
Note also the steepness of the rise when the black line turns up. “In a ten hour period, we went from 8,000 to 72,000 cfs,” said Raley. “That is fast. Very fast.”
The backline represents the inflow and the blue line represents the outflow. The rapid rise caused operators to open the gates wide at first. However, they also reduced the outflow when the inflow dropped. The two curves follow each other.
Inflow Higher than Harvey
The peak inflow during that rapid rise exceeded the peak inflow rate during Harvey.
The map and tables on the right indicate the peak flows coming from each tributary into Lake Houston.
Note how peak inflows from Lake, Spring and Cypress Creeks on the west were fractions of the volume coming from Lake Conroe.
Pre-Release Capabilities Constrained
Raley finished his presentation with a discussion of pre-release as a possible mitigation measure. The headline below says it all. Gone are the days of seasonal lowering.
At 700 cfs, the permit limit, Raley says it would take weeks to lower the lake. But weather predictions are not accurate that far in advance.
And if the storm misses Lake Conroe, a big release from the lake could make flooding in Lake Houston worse – especially if the storm misses Lake Conroe to the south.
So the SJRA tosses the responsibility back to the City of Houston, They make the City call for the water (out of its share of the lake) if the City wants Conroe lowered
Conclusion and Insight
Raley’s presentation won’t make flood victims feel better. But it may help them understand how difficult managing floods can be.
The important thing to take away from this is that there’s room in Lake Conroe for temporary storage of stormwater. And releasing that water so that it reaches populated areas downstream before or after the peaks coming from other tributaries will be the key to minimizing flood damage.
For instance, releasing a smaller amount after a larger peak has already passed won’t flood any more homes.
Remember, flood peaks are not necessarily additive. You can’t automatically assume that all peaks will hit at the same time and pile on top of each other.
I’m sure more knowledge can be acquired from close examination of this event. For instance, one of the big differences between this storm and Harvey was the downstream representation on the SJRA board by Mark Micheletti.
But Micheletti is the only downstream representative on a seven-person board. lf that continues, you can bet no substantial changes will be made in the long-term operation and policies of Lake Conroe.
Another thing to look at is whether keeping Lake Conroe at slightly lower levels during wet seasons would give dam operators more temporary storage, and thus protect more homes and businesses both upstream and down.
Posted by Bob Rehak on 5/24/24
2460 Days since Hurricane Harvey
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May 19, 2024 – For the second time this month, the West and East Forks of the San Jacinto River are flooding. The East Fork crested last night about 1.5 feet below the prediction. However, the West Fork is still rising at US59. Parts of River Grove Park and the turnaround under US59 are already flooded. And the National Weather Service predicts floodwaters will go even higher.
Meanwhile, the West Fork continues to run through an old Hallett sand pit that was sold in January.
Here’s what you can expect if you live near the rivers.
East Fork Crest Moving Toward Lake Houston
Low-lying areas along the East Fork began flooding yesterday at FM1485. Earlier, the East Fork flooded near Cleveland and Plum Grove. As the crest moves downriver, it is affecting communities differently. Exactly how depends on many factors, such as the conveyance of the river at different points, sediment accumulations, proximity of homes to the river and more.
Yesterday, water was coming across part of FM1485 where it crosses the East Fork and parallels SH99. Today, the entire east bound section of FM1485 was blocked by floodwaters.
East Fork San Jacinto at approximately 4:30 PM on 5.16.24
As of 6 PM, May 19, floodwaters are declining in this reach of the river. The crest has moved downstream toward Lake Houston.
Farther upstream, at FM2090, the river has already returned to its banks.
All this is the result of another 3-5″ of rain falling earlier in the week upstream in the watershed on grounds that were already saturated from torrential rains and flooding earlier this month.
NWS Issues Flood Warning for West Fork until Tuesday Morning
While the East Fork is falling at this hour, the West Fork is still rising. At 1:34 PM Sunday, the National Weather Service issued a flood warning for the West Fork near Humble affecting Harris and Montgomery Counties.
NWS will issue its next statement Monday morning at 7:45 AM CDT.
The FLOOD WARNING WILL REMAIN IN EFFECT UNTIL LATE TUESDAY MORNING.
IMPACTS: At 49.3 feet, minor lowland flooding begins in the vicinity of the gauge at US59. The north side turnaround at US 59 begins to flood. Low points in surrounding areas also begin to flood.
At 12:45 PM CDT Sunday, the river had risen to 49.2 feet.
Bankfull stage is 45.3 feet.
The river will crest at 49.7 feet just after midnight tonight. It will then fall below flood stage late tomorrow evening.
Flood stage is 49.3 feet.
This afternoon, the turnaround under US59 was just beginning to flood. The parking lots and part of the roadway were already underwater.
Far side of sandbar in middle is normally the river bank.
At 5 PM, the soccer fields, picnic area and boat launch at River Grove Park were also partially underwater. And water was rising quickly.
Picnic area and boat docks at River Grove underwater and going deepertonight.Soccer fields, also at around 5PMRiver still rising. Minor flooding expected through Tuesday.
Sand Mine Area Upstream
Farther upstream, the West Fork was still ripping a hole through an abandoned Hallett sand pit that the company sold to a real estate developer in January.
River is now flowing through the abandoned pit (right) instead of following the normal arc of the river (left) around the pit.Note trail of foam.It moved at around 5 mph.
This breach appears to have widened significantly in recent days. If it remains open and this pit becomes the new course of the river, it’s possible that the entire pit could become public property, just like the river is now.
On the other side of the river, Hallett filled in the trench that was releasing sludge from its settling pond last Friday afternoon.
Trench on perimeter of Hallett Mine that was releasing sludge into river on Friday afternoon has been filled in.
Lake Report
As of 7 PM, the SJRA is releasing 5,325 Cubic Feet per Second (CFS) from Lake Conroe. The lake is almost back to its normal level – within .67 feet of 201. And no rain is in sight. That’s good news. Releases should continue to go down.
Throughout this event, SJRA has balanced inflows and outflows to the degree that it can. The rate they show above is about half of what they released earlier in the weekend.
Lake Houston, however, is getting more, not less water. It is still about two feet above normal and discharging water via its gates and spillway. Total discharge is 34,015 CFS. Of that, the gates can release only 10,000 CFS. The other 24,000 CFS goes over the spillway.
Comparing the two numbers on the right, shows us that the flood risk is shifting to the Lake Houston Area now.
Of the 11 watersheds that send water into Lake Houston, SJRA controls only Lake Conroe. The East Fork has no flood control. But that’s a story for another time.
Posted by Bob Rehak on 5/19/24 at 8PM
2455 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.
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May 3, 2024 – As of 10 PM last night, the level of Lake Conroe had declined slightly for several hours. That indicates inflows are now less than outflows. Accordingly, San Jacinto River Authority Board Member Mark Micheletti worked out an agreement with the SJRA General Manager to start reducing the lake’s release rate.
By midnight the release rate was down from 69,585 cubic feet per second (CFS) to 64,797. And the lake level was down from 205.13 to 204.79.
This post contains information about the new release strategy, updated river and weather forecasts, plus a list of stunning rainfall totals from yesterday.
New Lake Conroe Release Strategy
During Harvey, many downstream residents felt the SJRA released too much for too long to return the lake to normal as quickly as possible.
The new agreement reached late tonight will have dam operators lowering the release rate in 2500 CFS increments. They will then wait two hours to see if the water level is increasing or decreasing, and adjust the next increment accordingly.
This strategy lets them delay additional decreases if necessary. For instance, if new heavy rainfalls increase inflows.
Dam operators still have the flexibility to release more if necessary. But it avoids leaving the release rate too high for too long when unnecessary.
All things considered, this strategy should protect downstream residents as much as possible. It also gives Lake Conroe operators a safety margin.
No Significant Changes to Flood Forecasts Since This Afternoon
As of 9:31 PM, Harris County Meteorologist Jeff Lindner had no changes to ongoing river forecasts. He emphasized that significant flood waves will continue moving down the East and West Forks of the San Jacinto into the weekend.
New Weather Forecast Reduces Rainfall Risk
Compared to yesterday’s weather forecast, however, Lindner also revised the expected overnight rainfall downward.
“Expect a mostly calm night with a low-end chance of a few showers toward morning. With heating on Friday and the approach of another thunderstorm complex from North Texas, there will be an increasing chance of rainfall during the day,” he said. “At this time. this complex of storms looks fairly progressive during the afternoon hours, but there is some uncertainty on how the storms evolve and how fast they cross the area.”
He says that additional rainfall amounts of 1-2 inches with slightly higher isolated totals can be expected on Friday. This additional rainfall is included in the river forecast models and should not greatly alter the current river forecast.
See river forecast summaries below.
East Fork San Jacinto River at New Caney (FM 1485)
Mandatory evacuation is still in effect for the eastern side of the river from FM 1485 to Lake Houston.
“Forecasted water levels will rise 7 feet higher than earlier this week. Structures on the ground will be flooded to rooftops levels,” says Lindner. “Elevated structures will be flooded. For reference, the forecasted water level is 4 ft below Harvey.” Similar to earlier this week, the rapid rise of several feet is expected late Friday into Saturday.
Impacted subdivisions:
Idle Wilde
Idle Glen
Cypress Point
River Terrace
Magnolia Point
Northwood Country Ests
Low-lying eastern portions of Kingwood, such as:
Riverchase
Woodstream
Woodspring Forest
As of Thursday at 9 PM
West Fork San Jacinto River at Humble (US 59)
The river will rapidly rise from upstream inflows. It will reach major flood levels and peak near 62 ft on Saturday. Widespread low-land flooding will occur. It will likely impact lower areas in West Fork subdivisions such as:
Belleau Woods
Rivercrest
Northshore
Forest Cove
Kings River Estates
Atascocita Shores
Kings Point
Kings Harbor
Kings River
Kingwood Greens
Fosters Mill
Kingwood Lakes
Barrington
Trailwood
Deer Ridge Estates
Kingwood residents should expect flooding of streets and structures near the East Fork, West Fork, and their tributaries.
Harris County is revising a potential inundation map that circulated Thursday on Facebook. Lindner says to expect the type of flooding we saw during the Memorial Days storm in 2016.
The following areas will be completely flooded with several feet of water: Deerwood Country Club, Deer Ridge Park, River Grove Park, Kingwood Country Club.
Elevated residents near the river should be prepared to be cut-off through the weekend if they don’t evacuate.
As of Thursday at 9 PM
West Fork of the San Jacinto River at I-45
Major flooding is imminent upstream and downstream of I-45 including large portions of River Plantation and portions of Woodloch downstream to SH 242 and SH 99. Flows may approach the I-45 bridge deck. The current forecast is about 1 ft below Harvey recorded levels.
As of Thursday at 9 PM
San Jacinto River Below Lake Houston
Major flooding is expected at all locations along the lower portions of the river.
Rio Villa will be completely inundated and cut-off and well as low lying in the river bottom around Highlands and HWY 90.
High velocity flows may damage vessels and barges near I-10 and result in loss of mooring.
Flow may approach the I-10 river bridge west of the river crossing. Additionally, high flows will result in the suspension of Ferry service.
As of Thursday at 9 PM
Spring Creek
According to Lindner, the creek is rising on the upper end due to flows from Waller and Montgomery Counties. Minor flooding is in progress along the upper portions of Spring Creek at Hegar Rd. Water levels along the creek are high, but any flooding is minor and to rural areas near the creek.
Willow Creek
Willow Creek has crested and is slowly falling.
Yesterday’s Storm: Gage Readings
The storm that swept through southern Montgomery and northern Harris Counties yesterday dropped impressive amounts of rainfall.
Harris County Flood Control District released the following totals at 7 PM Thursday.
8.24 in. – 1050 Spring Creek @ I-45
8.2 in. – 1320 Willow Creek @ Kuykendahl Road
7.76 in. – 755 San Jacinto River @ Lake Houston Pkwy
7.2 in. – 785 Peach Creek @ FM 2090
7.12 in. – 790 East Fork San Jacinto @ FM 1485
6.92 in. – 795 East Fork San Jacinto @ FM 2090
6.8 in. – 765 San Jacinto River @ SH 99
6.64 in. – 1745 Cedar Bayou @ FM 1960
6.6 in. – 1960 Luce Bayou @ SH 321
6.12 in. – 770 San Jacinto River @ SH 242
5.88 in. – 780 Caney Creek @ FM 2090
5.76 in. – 1040 Spring Creek @ FM 2978
5.64 in. – 1940 Luce Bayou @ FM 2100
5.48 in. – 1340 Willow Creek @ SH 249
5.12 in. – 1056 Mill Creek @ FM 1774
5.04 in. – 1950 Luce Bayou @ SH 99
5.0 in. – 1080 Spring Creek @ Decker Prairie-Rosehill Road
4.96 in. – 760 San Jacinto River @ US 59
Locations Out of Banks, Flooding Likely
HCFCD also reported that the following streams/channels were out of their banks and flooding was likely.
710 San Jacinto River @ Rio Villa
720 San Jacinto River @ US 90
740 Lake Houston @ FM 1960
760 San Jacinto River @ US 59
780 Caney Creek @ FM 2090
785 Peach Creek @ FM 2090
790 East Fork San Jacinto @ FM 1485
795 East Fork San Jacinto @ FM 2090
1054 Mill Creek @ FM 1486
1074 Walnut Creek @ Joseph Road
1084 Threemile Creek @ Joseph Road
1090 Spring Creek @ Hegar Road
1195 Mound Creek @ FM 362
1950 Luce Bayou @ SH 99
Flooding Possible
The following streams were still in banks, but flooding was possible.
The elevation of a home, business or street, visit the USGS National Map.
If in doubt about whether you will flood, remember. Better safe than sorry. If you evacuate needlessly, the most you lose is a day or two. But if you don’t and you flood, you could lose everything.
Posted by Bob Rehak on 5/3/24
2439 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2024/05/WF-Thurs-59-9pm.png?fit=899%2C693&ssl=1693899adminadmin2024-05-03 00:56:532024-05-03 00:56:55SJRA Reducing Lake Conroe Release Rate
Harris County Precinct 3 Commissioner Tom Ramsey’s Office will host a meeting about local infrastructure at Kingwood High School tonight. The meeting will include representatives from the City of Houston, San Jacinto River Authority, Congressman Dan Crenshaw’s office, and Harris County Flood Control District.
6:30-8:00 PM
The infrastructure meeting will follow an open-house format. After brief remarks, residents will be free to mingle with representatives from the various organizations at tables set up throughout the room. So you can come and go as you please.
This will give everyone a chance to discuss issues in depth. See details below.
Focus on Infrastructure
Infrastructure covers a lot of territory. Drainage. Roads. Parks. Water. And more.
What are upstream watersheds’ relative contributions to Lake Houston Area flooding? During a flood, where does all the water come from? Of course, it depends on how much rain falls where and when, and how long it takes to concentrate downstream. Rainfall is rarely uniform across an entire region.
But still, when considering hundreds of events over time, variations tend to average out. So, considering a hypothetical scenario that assumes a uniform distribution of rain can yield useful insights for planning flood-mitigation and conservation efforts.
Revisiting the January Flood
During late January 2024, the north and west Houston areas experienced widespread flooding. Even though most of the rain didn’t fall around Lake Houston, excess stormwater worked its way downstream over several days and wound up flooding the area. This caused widespread confusion.
During the event, many people put all the blame for downstream flooding on the 19,500 cubic-foot-per-second release from Lake Conroe. However, river gages showed upstream flooding in other watersheds as well. They included Lake Creek, Cypress Creek, Spring Creek and the West Fork below Lake Conroe.
Rainfall is rarely uniformly distributed across a region as large as Houston. But it’s not just how much falls where. The size of a watershed and how it converges with others also affect downstream flooding.
That prompted an interesting question that I asked Jeff Lindner, Harris County’s meteorologist.
Given uniform rainfall throughout the region, how much would each upstream watershed contribute to Lake Houston Area flooding during a 100-year rain?
Lindner worked with engineers at the San Jacinto River Authority (SJRA) to calculate the volumes below. Eleven different watersheds from seven counties feed into Lake Houston.
The table below summarizes their size in square miles, calculates the acre-feet of runoff in a 100-year event, and then determines each watershed’s percentage of the total passing through Lake Houston.
Upstream watersheds’ relative contributions to Lake Houston Area flooding.Assumes uniform distribution of rainfall throughout region.
The map below shows the location of each of the eleven contributing watersheds with the percentages above superimposed.
Map courtesy of SJRA. Percentages courtesy of Jeff Lindner and SJRA. Only watersheds draining through Lake Houston were considered for this exercise.
Observations
What can we conclude from these numbers? If rainfall is evenly distributed across the region:
Lake Conroe releases aren’t the only thing contributing to Lake Houston Area floods. SJRA controls only 13% of the runoff. That’s because the Lake Conroe Dam is the only dam in the eleven watersheds draining into Lake Houston.
Watersheds vary radically in their size – 7.5X. So we need to be careful when generalizing about the contribution of different areas to flooding.
37% of the runoff coming into Lake Houston comes via the East Fork San Jacinto and its sub-watersheds.
63% comes under the I-69 bridge into the West Fork between Humble and Kingwood.
35% of the region’s drainage comes down the West Fork and passes through an area between I-45 and I-69 with 20 square miles of sand mines.
In total, almost 2 million acre feet will drain into Lake Houston during a 100-year rain.
The implications of that last fact for flood mitigation are enormous.
One hydrologist I consulted for this post said, “I don’t know the exact amount of detention storage needed to significantly reduce flooding risks in Kingwood, but it will probably be at least another Lake Conroe’s worth of storage. That may help drive home the challenge facing HCFCD, SJRA, COH, and Montgomery County.”
And the money to accomplish that will likely take State and Federal backing.
Reviewing watersheds’ relative contributions to Lake Houston Area flooding may also be helpful in:
Visualizing where water comes from in a flood.
Determining the optimal locations for potential, regional, stormwater-detention basins/dams, such as those proposed along tributaries of Spring Creek.
Focusing conservation efforts, such as the Bayou Land Conservancy’s recent dedication of a preserve along Lake Creek.
Controlling sedimentation, i.e., planning for the retirement of West Fork sand mines, which have become leaky sieves.
As always, nothing clears brain fog faster than clean data, well summarized and presented. My thanks to Jeff Lindner and the SJRA for their help with this post.
Posted by Bob Rehak on 3/10/27
2385 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2024/03/image002.png?fit=330%2C326&ssl=1326330adminadmin2024-03-10 14:53:302024-03-11 11:43:35Upstream Watersheds’ Relative Contributions to Lake Houston Area Flooding
1/28/24, 2PM – After a week of near-constant rain and flooding, all river and lake gauges in the area show floodwaters receding, even if they aren’t below flood stage yet.
Whew! If you didn’t flood, you can stop worrying.
Nevertheless, the National Weather Service (NWS) still has flood warnings in effect for the areas:
Near the San Jacinto East Fork at FM1485 in New Caney. The warning affects people in Montgomery, Harris and Liberty Counties. Expect moderate flooding, primarily in low lying areas through Tuesday. The river is currently at 62′; flood stage is 58′ at that location.
West Fork around US59 until Monday afternoon. The river was at 51.4 feet, but bankfull is 45.3 feet.
Around Sheldon, below the Lake Houston Dam until tomorrow morning.
Photos Before, During, After Flood Crests
Below are 18 pictures I and a reader (who prefers to remain anonymous) took this week shortly before and after flood crests arrived. Each is dated and appears in chronological order. Together, they give you an idea of the extent of flooding. People who live in low-lying areas near major rivers were most affected.
But others, still suffering PTSD from previous floods, watched and waited with a sense of impending doom, wondering whether the water would claim their homes. It was a week of high anxiety and sleepless nights for many.
East Fork at Plum Grove
FM2090 over East Fork San Jacinto at Plum Grove. Thursday, 1/25/24.
It was hard to tell where the East Fork was at times. The river had penetrated an adjacent sand mine in multiple places and was flowing through it.
East Fork (upper left) broke through dike of abandoned sand mine and started flowing through it.Thursday, 1/25/24.Rising water flooded the sand mine and isolated an adjacent house. Thursday, 1/25/24.Looking west toward West Fork across Northpark South. Despite the ditch that contractors dug to drain the wetlands,a lot of water is still ponding. Thursday, 1/25/24.
West Fork in Humble/Kingwood Area
On Friday, 1/26/24, rising West Fork floodwaters near US59 invaded the neighborhood north of the bridge.West Fork at US59 on Friday, 1/26/24. Rising water flooded turnarounds under the freeway on both sides of the river.Friday, 1/26/24. Confluence of West Fork (right) and Spring Creek (left). Contrast enhanced to show that flow came predominantly from West Fork at this time.Saturday 1/27/24. Homes isolated by floodwaters just south of New Caney ISD’s New West Fork High School (upper right).Looking west, farther downstream on the West Fork at homes along Lake Point and North Shore Drives.Saturday 1/27/24. KSA River Grove Park parking lot, boardwalk, and bridge to soccer fields were all under water.Saturday 1/27/24. Golf course near Barrington subdivision flooded.Saturday 1/27/24. Edgewater Park at US59 and West Fork partially underwater.Kingwood County Club’s Forest Course becomes a Water Course south of Kingwood Greens subdivision.At Kings Harbor on Saturday 1/27/24, water topped the pier, and the riverwalk, but didn’t get into businesses.Sunday, 1/28/24. Looking at West Fork and adjacent sand mines from Northpark Woods. Note multiple breaches in dikes of two abandoned sand mines.Photo courtesy of reader.Sunday 1/28/24. Courtesy of reader. Looking west past Northpark Woods (lower right). Note level of water in ditch. Google Earth measurement shows the water extends more than 3,000 feet up the ditch. That’s more than half a mile.Farther up the ditch, you can see silty water from the mines on left and right mixing with water in the ditch.Photo courtesy of same reader.
Takeaways from Flood
I took several things away from this experience.
Sediment mainly moves during floods. It’s too early to tell how much moved and whether it will be enough to impair the conveyance of rivers, bayous, creeks and ditches. But this flood represents a major opportunity for the engineers conducting the SJRA’s sedimentation study.
Even relatively small amounts of rain (a couple inches per day) caused some major heartburn.
The SJRA’s modeling nailed the flood peak on the West Fork. Even when the National Weather Service was predicting a peak in the 52′ range at US59, the SJRA said it would be 53.5′. The actual peak was 53.71, within tens of an inch.
SJRA claimed the rainfall in the Lake Creek watershed was a major contributor. They don’t control that. It joins the West Fork downstream from the Lake Conroe Dam. A gage on Lake Creek showed 9.8 inches fell there in five days – among the highest totals for the region.
The recent freeze killed a lot of vegetation that would normally have slowed runoff. That contributed to faster, higher peaks, according to testimony given during the SJRA board meeting last week.
The SJRA did a much better job of communicating its gate operations to the public during this storm than ever before. It sent out a stream of press releases explaining what it was doing and why. I even received a personal call from an SJRA board member at 9pm before they increased their release rate to 19,500 cfs.
The timing of the calls to news media got the news of the release on the 10 o’clock news before people went to bed. During Harvey, that didn’t happen. Many people were caught sleeping in bed by rising flood waters and had to evacuate by boat. Lesson learned.
We need to do a damage assessment both upstream and downstream from the Lake Conroe dam to see where damage was concentrated. Did the SJRA do a good job of balancing upstream and downstream interests? Could gate operations have been improved?
The SJRA says it waited to release water until it got within 6 inches of the top of its tainter gates. Had the water gone over the top of the tainter gates, they could have lost control. The gates would have become inoperable and the dam could have been placed in jeopardy.
One leading hydrologist told me, “Understanding watershed hydrology is difficult. It rained quite a bit over a very large area. Watersheds all respond differently. The timing of the runoff reaching channels is crucial. How it combines with all of the other runoff from different places is key.”
We need more floodgates on Lake Houston.
The worst of this event is behind us. Now comes the hard part. Cleaning up.
I wasn’t able to cover every area that flooded during this event. So, if you have photos of the flood or its impact that you would like to share, please submit them through the contact page of this website. Understand that all photos used here are in the public domain and may be shared by others. Finally, please indicate whether you would like a picture credit, and if so, how it should read.
Posted by Bob Rehak on 1/28/2024
2343 Days since Hurricane Harvey
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