8/12/2026 – On 8/11/26 in a two-part meeting, the Lone Star Groundwater Conservation District (LSGCD) voted to increase groundwater pumping and ignore subsidence…at least for now. The first part of the meeting included a discussion of how they arrived at their recommendations and public comments on “Desired Future Conditions” (DFCs). The second part included formal ratification of the DFCs by the LSGCD Board.

To those unfamiliar with LSGCD politics, it was an afternoon/evening filled with bizarre, unexplained contradictions.

Bizarre, Unexplained Contradictions

For instance, the LSGCD:

1. Reviewed a presentation which stated their legislatively defined mission is striking a balance between “the highest practicable level of groundwater production” and other factors, such as recharging of aquifers and “control of subsidence.” They then decided to:
   • Adopt a production rate three times higher than the recharge rate of aquifers
   • Ignore subsidence, without explaining why.
2. Left their DFC unchanged because new modeling showed they could double groundwater production without endangering future supplies. But then they failed to explain how they tweaked a USGS model to obtain those results.
3. Claimed to welcome public comment. But then they attacked the qualifications of the commenters including people with PhDs and MUD directors.
4. Received a grand total of six public comments in 90 days, but acted as though they were sick and tired of hearing the same old stuff.
5. Claimed the Harris-Galveston Subsidence District chose not to work with them, when they limited subsidence districts to making three minutes of public comments.
6. Read a high level summary of public comments submitted earlier without addressing any of the concerns those comments expressed.
7. Said no other groundwater conservation districts adopted a subsidence metric…without addressing the reasons why.
8. Claimed they were no longer “averaging” well declines. But then they adopted a DFC based on a closely related word “median.”

Adopted DFC Contains Huge Loophole

In the end, the LSGCD board adopted a DFC that says, “In Montgomery County, no less than 70 percent median available drawdown remaining in 2080 in the Gulf Coast Aquifer between 2018 and 2080.” See below.

What does that mean? LSGCD wants to manage groundwater pumping so that, in the median well used in their calculations, at least 70% of the aquifers’ usable vertical water column remains available compared to the baseline determined in 2018.

It implies that they plan to pump no more than 30% of the water out of the aquifer(s). But the word “median” means that not every well must adhere to the 70% limit. Half of the 12,000+ wells that LSGCD tracks will draw more…sometimes far more. And half will draw less. That’s what “median” means.

And that’s important in a county where the southern half is growing quickly and the northern half remains largely rural. The DFC by itself doesn’t tell you how many feet groundwater levels could fall in The Woodlands, Conroe, Magnolia, Porter, etc.

Nor does it tell you how over-pumping in those areas could affect subsidence. That is a major change in policy emphasis. Lone Star says it has spent millions on drilling, coring and laboratory work since 2023. But it does not support adopting a subsidence metric at this time. Instead, it simply intends to continue monitoring subsidence. But once subsidence happens, it’s impossible to reverse.

Meanwhile, a 2022 report (which LSGCD participated in) anticipated 3-4 feet of subsidence by 2080 in southern MoCo…and that’s at the old pumping limit which LSGCD hopes to increase dramatically.

Impacts on San Jacinto Watershed

For the San Jacinto watershed, even relatively small amounts of differential subsidence matter more than they would in a steeply sloped watershed.

Kingwood, Spring Creek, the West Fork, Lake Houston and much of northern Harris County have an extremely flat slope. Subsidence doesn’t necessarily cause flooding by itself, but differential subsidence can alter:

• Channel and overbank gradients
• Drainage-system slopes
• Floodplain elevations relative to river stages
• Detention outfall elevations
• Bridge and culvert relationships
• Relative elevation of homes versus floodwaters.

A few tenths of a foot may be immaterial in some settings. But…

And this creates a governance problem. LSGCD can authorize groundwater pumping in Montgomery County whose hydraulic and subsidence effects do not necessarily stop at Spring Creek, while Harris County bears some of the downstream flood-risk consequences.

The regional aquifer system is interconnected. A county-by-county median statistic can conceal substantial regional drawdown. A DFC based on countywide median remaining well drawdown contains no explicit constraint on resulting land subsidence.

Before concluding that the recommended 200,000 acre-feet-per year is benign, LSGCD should produce maps of modeled 2018–2080 drawdown and modeled subsidence in feet for southern Montgomery County and northern Harris County, ideally centered on Spring Creek/Kingwood. That would turn this somewhat abstract “% remaining” statistic into something much more meaningful. But Lone Star didn’t show that yesterday.

However, a new interactive map produced by Harris-Galveston Subsidence District this year is based on new satellite data. It averages subsidence in the last four years and computes a centimeter/year rate. It’s amazingly detailed and corroborates the 2022 blueish map above. See below.

The colored map shows that large parts of southern Montgomery County and northern Harris County bordering Spring Creek are subsiding at a rate greater than 2 centimeters/year. By the end of the planning period in 2080, that translates into approximately 3.5 feet.

Much of Kingwood and Humble are also subsiding at rates that could negate the safety margin (feet above floodplain) for many homes built close to floodplains. That’s because the Lake Houston Dam is sinking at a tiny fraction of rates upstream. Therefore, subsidence is essentially tilting the lake upstream toward homes that were once above the floodplain.

Note that these subsidence rates were determined under LSGCD’s old pumping rates. The proposed new rates would accelerate subsidence even more.

Impacts on Future Growth/New Development

Notice the big white area (not subsiding) north of the county line near the middle of the colored map above. That’s the 5,300 acres where Scarborough hopes to build 7,000 homes. They would all be on well water. And that would dramatically increase subsidence in the areas around them.

So, if you haven’t already signed the petition against this development, please do so now.

For More Information

To view videos of yesterday’s meetings, visit the LSGCD Meetings Page. Also see public comments submitted by:

• Mike Turco, general manager, Harris-Galveston Subsidence District
• Benjamin Slotnik, PhD, MoCo resident
• Paul Cote, former MUD president for 10 years (also submitted to TWDB)
• Neil Gaynor, MoCo resident
• Bill Beran
• Laura Norton, M|UD 47 President

Note: this is a step in a process. LSGCD recommendations must still be approved by the TWDB. And thankfully, LSGCD has elections coming up soon.

Posted by Bob Rehak on 8/12/2026

3270 Days since Hurricane Harvey