Tag Archive for: Dupré

UH Geology Professor Weighs in with TCEQ on BMPs Related to Sand Mining

Professor Emeritus William Dupré, Ph.D., of the University of Houston’s Department of Earth and Atmospheric Sciences filed a 36-page report with the TCEQ on sand mining in the San Jacinto River Basin. Dupré has broard experience with geologic hazards and risk assessment. He submitted his report in support of the petition filed with the TCEQ by the Lake Houston Area Grassroots Flood Prevention Initiative to establish best management practices (BMPs) for sand mining.

The first issue that Dupré identified is flooding. “With one exception, all sand mines in the San Jacinto River Watershed are located partially or completely within the regulatory floodway, an area delineated by FEMA as having the highest potential for flooding (and erosion) along major waterways. “[T]he floodway is an extremely hazardous area due to the velocity of flood waters which carry debris, potential projectiles and erosion potential…”. (Montgomery County Flood Plain Management Regulations, 2014, p.25)

Floodway Constriction

Dupré notes that partitioning large areas of the floodway from rising floodwaters by levees and dikes can result in increased flooding of adjacent areas.

A good example: sand mines on the north side the San Jacinto West Fork and I-45 have walled off half the floodplain, forcing floodwaters onto neighboring property on the south side.

Sand mines have walled off more than 200 acres west of I-45 and north of the San Jacinto West Fork. See below.
The high dikes force floodwater to the other side of the river rather than allowing it to spread out on both sides. The concentration of water in a smaller area also increases the velocity and erosion. For close-up of area inside red circle, see image below.
This shows how high the dike around the sand mine is.

Levee Failure Can Flush Pollutants into Waterways

“Flood-induced breaches in levees can also add to the problems of flooding, erosion, and sedimentation downstream,” Dupré says, flushing sediment and other pollutants into adjacent land, wetlands, and waterways. See two examples below.

In the top row, river migration eroded the pit wall which allowed the contents to drain into the West Fork near North Park Drive. In the bottom row, the entire contents of a mine pit drained into the West Fork near Bennett Estates.

In-Stream Mining Disrupts River Habitat

A. Google Earth image of point bar on the west Fork of the San Jacinto River; B. Same bar 5 months later showing un-permitted (i.e. illegal) In-stream “bar-scalping.”

“Since the passage of Section 404 of the Clean Water Act Amendments of 1977, some states have heavily restricted or banned in-stream mining, as have many countries,” writes Dupré. “These restrictions are mainly based on the significant environmental problems associated with this type of mining.”

Such mining can create major disruptions of riparian habitats by increasing the amount of sediment put into suspension. “Major channel modifications can also occur, including upstream incision (headcutting) and downstream erosion and deposition.”

BMPs Can Make Compliance with Regulations More Efficient

In his paper, Dupré next examines applicable regulations and suggests several BMPs to supplement them. He recommends that:

  • All APO’s should develop and make available to regulators and the public a Comprehensive Mine Plan and an Environmental Assessment Report on potential impacts before permits are issued.
  • Likewise, all APO’s should develop and make available to regulators and the public a Reclamation Plan before permits are issued and file a performance bond ensuring reclamation before a production permit is granted. Such permits should have significant civil and criminal penalties for non-compliance.
  • New mining should be minimized or restricted in delineated floodplains and floodways and channel migration zones (areas most like to be eroded by lateral migration and river avulsion).
  • Mines should be “prohibited within the adopted regulatory floodway unless it has been demonstrated through hydrologic and hydraulic analyses that the proposed encroachment would not result in any increase in flood levels…. A development permit must be secured from the Flood Plain Administrator prior to the placement of fill or other encroachment in the floodway….” (Montgomery County Flood Plain Management Regulations, 2014).
  • Stockpiles should be located outside the floodway, because of the high potential for erosion (and resultant sediment pollution) during frequent flooding.


Dupré acknowledges that aggregate mining clearly provides valuable material and employment to the state and nation.

Nonetheless, Texas is one of the few states where sand and gravel mines remain largely unregulated. Issues related to flooding, erosion, and sedimentation create many unintended (and undesirable) environmental and economic impacts associated with sand and gravel mines – especially in the San Jacinto River watershed. “I believe there is a clear need for the requirement for BMP’s to better protect the public and the environment,” says Dupré.

TCEQ Public Comment Period Rapidly Coming to a Close For Sand Mining BMPs

On November 11, the TCEQ held a public hearing on a joint proposal between TACA and the Lake Houston Area Grassroots Flood Prevention Initiative to establish best management practices for sand mining in the San Jacinto watershed. The public comment period closes on December 11, 2020 – in just 12 days.

If you want to weigh in on the subject, you can review presentations from the hearing here. TACA and the Lake Houston Area people are in substantial agreement on most points. However, they still differ on four key issues.

  • Where should the BMPs be enforced? On the main stems of the East and West Forks or on the smaller tributaries, too?
  • Should there be performance bonds for reclamation?
  • How far from rivers should the sand mines be set back for safety reasons?
  • Should compliance with best practices should be voluntary or mandatory?

If you have comments or questions for the TCEQ, please e-mail Outreach@tceq.texas.gov. Make sure to include “Sand Mining Rulemaking” in the subject line of your e-mail.

Posted by Bob Rehak on 11/29/2020

1188 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.