Headcutting and Hungry Water

by Cynthia Andre

It is twilight on a July night. There is a mist lying in the bottom, made softly luminescent by a gibbous moon still low on the horizon. Fireflies blink and weave through the fog, completing the sometimes-ethereal experience of a warm, summer night on a creek in the Ozarks.

The pleasant, familiar sounds of katydids, Chuck-will’s-widows, and barred owls calling to one another through the summer night cannot be heard, however, over an all too familiar noise these days on creeks statewide – the jarring noise of a large dump truck in low gear making the last climb out of the valley for the night and the uneven, angry whine of a front-end loader down on the gravel bar.

That, some people would say, is the sound of money – $41 million dollars in Missouri alone in one recent year. In one weekend, working round-the-clock, an operator can mine as much as $80,000 worth of sand and gravel from one stream site. And there is an almost inconceivable amount of gravel being removed nationally from our rivers and streams – 1.1 billion tons in 1998, up from 800 million tons in 1980. That buys a lot of lobbying power.

It also buys legal representation. In a lawsuit ending in l997, the sand and gravel mining industry successfully challenged the regulation of their industry by the Army Corps of Engineers (except where gravel is moved about within the stream.) When the Corps’ appeal was lost in January 1999, regulation in our state reverted to the Missouri Department of Natural Resources (MDNR), Land Reclamation Program.

Although MDNR issued permits for gravel mining for three years prior to the Corp taking over that function, guidelines for the industry were not actually developed until that time. There were, therefore, no stream protection guidelines for this industry in Missouri when permitting reverted to DNR in 1999.

While it is old news that gravel mining can have negative effects on streams, research in the last few years has clarified some of these effects. Generally, these fall into two categories – physical changes in the channel and changes associated with increased sediment in the water.

Physical changes in the channel itself can be caused by removal of gravel from either within the stream or beside the stream. The removal of gravel from within the stream creates a “nick point”, which moves upstream during high water, a process called “headcutting”. This lowers the streambed (called “channel incision”) and destabilizes the banks, sometimes for miles. In such cases, operators who mine in one area over many years are actually mining gravel from some other landowners’ banks upstream, destabilized by their mining activity.

The channel, now deepened below the nick point, will cause the stream during high water to drop its gravel load, as the water in this area is moving more slowly. This creates what is known as “hungry” water below this point, i.e. water that is relieved of its gravel load. Moving faster and with more energy now in the normal channel downstream, “hungry” water has an increased capacity to scour and erode the streambed and banks.

The removal of gravel from beside the stream can also cause problems, most frequently resulting in a widening of the channel. This changes the water temperature, affecting the species of aquatic wildlife that can live there. Less frequently streamside gravel removal can change the stream channel itself when areas of excavation deeper than the water level within the stream “trap” the channel during flooding.

An increase of sediment in the stream, often associated with sand and gravel mining, has a number of harmful effects. Decreased visibility for aquatic wildlife interferes with reproduction and food gathering. Increased sediment can also decrease light levels for algae and aquatic plants, negatively affecting the aquatic food web and altering the environment for organisms dependent on the use of aquatic plants for reproduction and protection from predation.

Further, increased sediment in the stream can smother fish eggs and fry negatively affecting fish survival rates and can alter the streambed environment, eliminating habitat for some of the macroinvertebrate species on which many fish feed.

Finally, disturbance of the banks and streambeds can release old mine tailings and other pollutants, redistributing them in the stream.

Research has also shown that the industry can actually cost states more money than it generates when costs to society – lost farm revenue, real estate value, fishery productivity, and recreational spending – are factored in. Too, damage to infrastructure such as bridge piers, exposed buried pipelines, and utility lines caused by channel incision must be borne by the public as well.

In March 2000, with evidence mounting of environmental problems associated with sand and gravel mining, the Land Reclamation Commission requested staff to begin the process of establishing guidelines for gravel mining as a part of the state permitting process.

In September 2001, the same guidelines developed by all stakeholders for use by the Corps were published in the Missouri Register, but bowing the pressure from the industry, these rules were terminated and four public hearings were held.

The public hearings were attended predominately by operators, representatives of companies using gravel, and those who are currently statutorily exempted from the permitting process – government entities and private landowners. The comments were overwhelmingly negative, threatening to end the process. When those interested in protecting streams were finally alerted to the situation, however, the Commission received approximately 200 letters in favor of adopting the guidelines.

Seeking some consensus, the Commission then agreed that a workgroup consisting of representatives of all the stakeholders be formed to once again review the guidelines. On September 9th two representatives of the Sierra Club sat down with 31 other stakeholders to begin this process, which is scheduled to be completed by late November.

But once again sand and gravel operators are seeking to bypass regulation. State senators and representatives have reportedly responded to the industry’s entreaties by urging the Commission to abandon their attempt to develop guidelines for the industry.

ACTION: Please contact your state senator and state representative. Request that they support the adoption of the stream protection guidelines for sand and gravel mining in Missouri requested by the Land Reclamation Commission and being currently reviewed for their consideration. (Using your zip+4 code, you can e-mail or find the phone number or address of your state senator and representative at the following website: http://www.senate.state.mo.us/zipsrch.htm.)