Tag Archive for: sand mining

More About Sand Mining than You Ever Wanted to Know

Regular readers of this site will notice something new today – a top-level page that contains links to information about sand mining best practices.

The page features four categories of information about sand mining:

  • Best management practices from other states and countries
  • Academic articles and case studies
  • Texas laws and regulations
  • Observations

The material within each category ranges from easy-to-understand to for-experts-only. Descriptions beneath each link hint at the nature, content and authorship of the entry along with its degree of difficulty.

I hope to expand the page over time. If you know of additional valuable references, please send me links.

Knowledge: Your Best Defense

People who have closely followed the sand mining debate in the Lake Houston area know that the Texas Aggregate and Concrete Association and others have pushed back against this website.

Sand mine in Porter next to Caney Creek covers approximately 600 acres as of Hurricane Harvey. Kingwood’s East End Park, just downstream from here, had 30 acres covered with sand up to 10 feet high after Harvey.

I believe that such debate is healthy. I also believe that informed people can make better decisions about what’s in the public interest and their own self-interest.

Start with Louisiana

If you want to learn more, the Louisiana Best Management Practices represent a great place to start. Louisiana has geology, topology, weather, climate and vegetation much like ours. Beyond that, the document is clear, concise, well-illustrated and well researched…and balanced. It contains sections that explain why we need sand mining and how it’s done. It also contains good descriptions of the dangers. Then it describes best management practices and explains how they can help mitigate those dangers.

Similarities Around the World

As you explore best practices, notice their similarity throughout the world. Our problems are not unique.

Pay particular attention to recommendations pertaining to:

  • Setbacks from the river
  • Slopes of dikes
  • Location and protection of stockpiles
  • Vegetative ground cover
  • Buffer zones
  • Remediation
  • Erosion control

Huge Gaps Exist Between Desired, Required, and Actual Practices

Be mindful of the distinctions between desired, required and actual practices. Best practices lead to best outcomes. Required practices usually lead to minimally acceptable outcomes. Actual practices sometimes fall short of even those. That’s why I’ve also included the section on laws.

Statewide, sand mine operators received more than 600 fines for violations in the last five years.

After reviewing laws and best practices, browse through the aerial photos of sand mines on this site and ask yourself, “Are they complying with laws and observing the industry’s best management practices?”

If your answer is “No”, ask “Why?” And DEMAND answers.

Finding the Solution to Pollution

Sand comes at us from many sources, some natural and some man-made. We can’t stop nature, but we can stop harming ourselves.

  • Our lake and river are rapidly filling with sediment.
  • Drainage ditches are backing up into neighborhoods.
  • Water filtration costs are high.
  • Turbidity is high.
  • Oxygen in the water is low.
  • Recreation, boating and fishing are impaired.
  • Dredging will cost tens, if not hundreds, of millions of dollars.
  • Maintenance dredging will cost even more.

Demand Excellence, Not Just Compliance

We must hold the mines to the highest standards if they want a license to operate next to the source of drinking water for millions of people. Violations are simply not acceptable.

Also, any solution must acknowledge that this region is prone to repetitive flooding. We’ve had FIVE five-hundred year storms in the last 24 years (1994, 2001, 2015, 2016, 2017). During each, we also had huge releases from Lake Conroe that exacerbated flooding.

If mine design cannot withstand these types of events, we invite disaster. The most sediment transport happens during floods; it’s time we started planning for them.

How You Can Help

All of us are smarter than one of us. You may see things that I missed. Please review the aerial photos, best practices and laws. If you see opportunities for improvement, send them to me.

Example: Alaska, I noticed, discourages mining within 1000 feet of a public water source. Here, the sand mines operate right next to ours and even drive trucks through it.

Sand mines on the west fork of the San Jacinto adjacent to Kingwood. Note how close they are operating next to the source of our drinking water. Also note what appears to be a breach of the dike between the mine on the left and the river about two-third of the way up the left side of the photo. Photo taken after Harvey on 9/14/2017.

 

Sand mine on the West Fork of the San Jacinto adjacent to Kingwood. Industry best practices elsewhere discourage running vehicles through water sources. Here the operator built a road right through the river. Also notice the steepness of the dikes. Most best management practices recommend setting them back from the river, sloping them at 3:1 to 10:1 and planting them with vegetation such as grass to retard erosion. 

 

Fresh sand deposits after Harvey coming out of the sand mines on the west fork of the San Jacinto adjacent to Kingwood. Note that the height of the dune is engulfing several medium sized trees on the right. Also note the road leading to the river on the left and machinery at work in an area unprotected by dikes.

Let’s compile of list of such observations, then start a dialog with the sand mining industry to encourage voluntary compliance with best practices and improve disaster planning.

Posted on 6/15/18 by Bob Rehak

Day 290 since Hurricane Harvey

Where did all the sand come from?

Our San Jacinto River is clogged with sand that impedes the flow of water and contributes to flooding. Where did all the sand come from? When? Under what conditions? Are there ways to reduce the volume of sand coming downstream? As the U.S. Army Corps of Engineers prepares to dredge the San Jacinto for the first time, we should ask ourselves these questions.

The river has eight tributaries that affect the Lake Houston Area: Spring Creek, Cypress Creek, Lake Creek and the West Fork on the west; and Peach Creek, Caney Creek, Luce Bayou and the East Fork on the east. All produce sand naturally.

They send sand downstream at different rates at different times, depending on the location of rainfall within the watershed, the volume of flow, the speed of flow, and management of the flood gates at Lake Conroe.

San Jacinto River Watershed Map. Tributaries affecting the Humble/Kingwood area include: Cypress Creek, Spring Creek, Lake Creek, West Fork, Peach Creek, Caney Creek, East Fork, and Luce Bayou.

Other factors include the percentage of sand content in soil and the health of vegetation along stream banks. Vegetation retains and slows runoff, reducing erosion.

 

The Natural Resources Conservation Service of the USDA produced this soil map of Montgomery County. Blue colors indicate highest percentage of sand; red colors indicate the lowest. Note huge concentrations of sand on Spring Creek and West Fork.

The map above helps us understand why so many sand miners chose to locate along the West Fork – lots of sand. The West Fork is also sparsely populated compared to Spring Creek as you can see in the satellite image below. It shows the sand mines around the Humble/Kingwood area highlighted in red. One is located on Caney Creek (right); the rest are on the West Fork (left).

Satellite image from Google Earth with sand mines around Kingwood outlined in red. Image dated 10/28/2017.

While sand has been coming down the river and streams for thousands of years, rapid sedimentation in the West Fork between Humble and Kingwood didn’t become an issue until the growth of sand mining on the West Fork in the late 1980s.

Notice how most of the areas in red above are filled with natural vegetation in the 1985 image below.

Satellite photo of Kingwood area in 1985 before rapid growth of sand mining. Compare areas in red to previous image.

Today, mines expose approximately 20 square miles of loose sand on the West Fork alone between I-45 and US59.

Aerial photo taken on 9/14/18 of sand mining operation on West Fork.

Dikes around the mines are supposed to keep sand from being discharged into the river. However, Harvey inundated the mines.

Harvey’s floodwaters topped the dikes of sand mines. Image taken 8/30/2017.

An analysis of satellite images before, during and after Harvey shows massive loss of sand from stockpiles within many of these mines.

During floods like Harvey when the SJRA releases water from Lake Conroe, dikes are overtopped and broken. I suspect that sand then comes down the West Fork in tremendous volumes that dwarf Spring Creek’s contribution.

To test this hypothesis, I looked at USGS flow data for both tributaries. I also reviewed all my aerial photos and Google Earth’s historical images.

Under normal conditions, Spring Creek flows at 80 cubic feet per second (cfs) and the West Fork of the San Jacinto at 150 cfs. These are not sufficient flow rates to suspend sediment the size of sand. (For an excellent discussion of sedimentation, see Fundamentals of Sediment Transport at Fondriest.com.)

However, during Harvey, Sring Creek flowed at 78,200 cfs; and the West Fork at  55,000 cfs. Then the San Jacinto River Authority opened the gates at Lake Conroe. That flipped the ratio dramatically. With the flood gates open, Spring Creek still flowed at 78,200 cfs, but the West Fork increased to 130,000 cfs. Flow rates that high can (and did) move houses off their foundations.

Four hundred and fifty aerial photos in the gallery of this web site show a bright, white trail of sand between sand mines and the sand clogging the East and West Forks around Humble and Kingwood. Flood waters swept that sand from a to b. The giant sand deposits at River Grove Park and elsewhere grew exponentially during recent floods.

This tells me that when discussing the origins of the sand, we need to primarily evaluate the river during floods. More water is moving faster under greater pressure. That’s when erosion and deposition happen quickly. That’s when the river overtops and ruptures dikes. And that’s when twenty additional square miles of exposed sand surface on the West Fork make their major contribution to our sediment and flooding problems.

We can’t control sand coming down rivers naturally. However, with better sand mining practices, we may be able to reduce mankind’s contribution to our flooding problem, not to mention the related cleanup costs borne by taxpayers.

In upcoming posts, I will discuss my research into sand mining best practices.

Posted May 22, 2018 by Bob Rehak

266 Days since Hurricane Harvey