When earth is moved during construction, it can more easily wash away to areas it doesn’t belong and adversely affect farmland and wildlife.
Not only is erosion a problem for the environment, but minimizing its negative effects is the law—Iowa state and federal laws require erosion and sediment control (E&SC) measures to protect the delicate natural balance.
Iowa DOT has a variety of time-tested E&SC practices in place, but it wasn’t clear whether these were the most effective or whether there were other approaches that could be undertaken to achieve better or cheaper results.
Over two construction seasons, researchers studied a range of E&SC methods and determined which worked best and what needed improvement.
Highlights of the findings include cost-effective new techniques for building wattles (low-lying barrier rolls, pictured) and fabric fences to maximize stability and erosion control.
Research also showed that water retention ponds might not be as effective as had been previously thought, leading to important new areas of inquiry.