Mud Doesn't Just Happen
by Dr. Ben Dysart

Dr. Ben Dysart delivered the keynote address at Upstate Forever’s Dealing With Dirt Conference last fall. Because of space limitations, this article is a highly condensed version of his speech. The entire speech is available upon request. Dr. Dysart, who earned his doctorate in environmental engineering at Georgia Tech, was on the Clemson faculty for over 20 years, is the former chairman of the National Wildlife Foundation, and now is the president of Dysart’s Associates, an environmental consulting firm.

     My mission this morning is to help you shift from an “obstacles” or “barriers” perspective vis-à-vis erosion and water quality to a perspective that focuses on possibilities. I want to debunk in the most forceful and specific terms possible the myth that “mud just happens”–that you can’t protect both in-stream water quality and the bottom line.

Among the features that kept sediment on site at the Big Creek project were a diversion berm and two rows of silt fences.

I’ll use the landmark “Dirt 2 Project” from the Atlanta metro area as a real-world case study that demonstrated that a real win-win-win was attainable. Dirt 2 was a follow-up to “Dirt 1,” which was a panel appointed by then Lt. Governor Howard and the Georgia Senate Erosion Special Committee. Dirt 1 had recommended a rigorous in-stream turbidity standard – 25 or 50 NTU – but had left open the question of how or even whether such a standard could be attained. Dirt 2’s focus was to be how to meet a rigorous performance standard, and meet it in a cost-effective manner.

From the start, most people said it simply couldn’t be done technically. The general consensus was that effective erosion control was unattainable, at least at anything approaching a reasonable cost. But technical issues weren’t the real problem.

The real problem was that nobody expected erosion control to work. Plans typically weren’t installed and maintained properly. Designers weren’t necessarily even expected by anyone to produce designs that performed. And everybody knew it. There was lots of finger pointing and looking away; lots of rolling eyes and lots of denial. And as a consequence, the Chattahoochee River and its tributaries still ran red – too red – whenever it rained.

Dirt 2 introduced into this dead-end dynamic the notion of the need for a real paradigm change. We believed that incremental tinkering would not help. We were not content with a plan that simply placed a series of components around a site as indicated on a piece of paper that had been stamped “Approved.” As such, our focus was on performance of erosion control systems – actual results – not just on finding new ways to install silt fences.

So Dirt 2 embarked on a demonstration project at Big Creek Elementary School in Fulton County, a new school on a site that bordered a tributary to the Chattahoochee.

This was no academic exercise, where researchers had plenty of time and money to run endless experiments. This was the real world – a school had to be built on time and within budget.

Now surely you haven’t seen any “rocket science” in this new paradigm. It is certainly a huge departure from the status quo. But rocket science it is not.

So what did this new paradigm look like on the ground? First of all, perimeter controls had the whole site zipped up tight before site clearing began. Second, the creation and maintenance of effective systems of stormwater collection and detention were integrated into the construction management plan. And finally, clean, treated effluent was released to functional vegetated buffer areas where it soaked back into the ground.

The result was drastic reduction in total suspended solids and turbidity in Big Creek – despite the fact that this was a major construction project that required extensive site preparation. In other words, the waters of the state were unharmed.

The resulting bottom line was strongly positive on a number of fronts. First, the very demanding and diligent neighbors and community were happy. Second, the owner – who simply couldn’t afford interventions and delays – stayed on schedule and was very happy with the way the project unfolded. And third, the constructor trained a lot of their staff company-wide on the new paradigm, and gained a bottom-line competitive advantage as a result.

An unfortunate but common scene in the Upstate: A collapsed silt fence allowing the escape of massive quantities of sediment. It doesn’t have to be this way.

What’s more, not only did we accomplish very effective erosion prevention and sediment control during the project, but many of these same controls are now being used for reducing runoff by infiltrating water and recharging the groundwater. Despite the addition of a substantial amount of impervious cover to the landscape, runoff in both peak and volume terms remains largely the same. As a consequence, the entire fluvial system – fish, aquatic invertebrates, the stream’s transport capacity, and stream banks – remains in equilibrium.

And the cost? According to the construction manager, this project was within standard parameters for projects of this type. Developers typically expect erosion-control work to account for about three to five percent of site work costs. At Big Creek, the tab for erosion control was six percent. Not bad for the very first time the Dirt 2 paradigm was implemented.

So the upshot is this: without rocket science or busting the budget, you can produce clear water – if you want to.It’s up to you –it’s a conscious choice.