For the seventh year in a row, the Ohio River tops the charts as the most polluted body of water in the U.S., according to the Ohio River Valley Water Sanitation Commission. The removal of these chemicals can be a daunting task for those such as Brad Smith, program director at the Southwest Indiana Program Office of the Nature Conservancy.
Smith says no one practice is going to solve all the problems, but he hopes small practices incorporated by the Nature Conservancy will lead to solving the larger issues. In 2009, the nonprofit conservation organization Indiana chapter began promoting a new practice to address the chemicals impacting the waterways.
Originally developed by engineers at Ohio State University, the Nature Conservancy (the largest environmental nonprofit in the Americas in assets and revenue) is working with landowners to prevent polluted runoff from entering the area streams by using an innovative drainage ditch design called the two-stage ditch. By leveling the banks of conventional ditches to 2 to 3 feet above the bottom for a width of around 6 to 20 feet on each side, the two-stage ditch allows the water to spread and slows the velocity of water runoff.
“There is a lot of attention right now on water quality and excess nutrients in our waterways,” says Smith. “Last summer, Toledo, Ohio, had to shut down their water supply, and you had an entire city without water. There is a whole lot of attention on addressing these sources of pollution. This is a way to help identify how we can address these problems in a proactive way and not wait. This is a way for people to be proactive.”
It’s this kind of nightmarish situation that left nearly half a million people without drinking water last August in Northern Ohio that the Nature Conservancy is trying to prevent from happening in Evansville.
The two-stage ditch method mimics a more natural stream channel when compared to conventional ditches, says Smith. The ditches help slow water flow and reduces the amount of downstream flooding, which results in less harmful nutrients entering water sources. These excess nutrients such as nitrogen and phosphorus find their way into the Wabash River, which feeds into the Ohio and later the Mississippi, and then the Gulf of Mexico. Indiana’s state river, the Wabash River, is 503 miles long and flows southwest from Ohio near Fort Recovery across Northern Indiana to Southern Illinois where it drains into the Ohio River.
Both nitrogen and phosphorus are common in farmers’ fertilizers to increase crop yields or from power plant emissions. Research shows that a half-mile two-stage ditch reduces nitrogen by 53 tons per year — the weight of 17 elephants.
“Nitrogen is a big contributor for water quality problems all the way down to the Mississippi,” says Smith. “This kind of approach is trying to address that problem at its source. It comes from the Corn Belt of the Midwest. While a single two-stage ditch is not going to make a huge impact in itself, we want to promote the practice so people can incorporate clean practices.” In Toledo’s case, toxins produced by algae were found in the water supply and algae multiples from an overabundance of phosphorus.
Smith calls the practice “self-cleaning ditches,” after seeing a great improvement of aquatic life coming back to grow and live as well.
The Nature Conservancy began implementing the method in the northern part of Indiana and in the last two years, its work has brought the organization to Vanderburgh and Warrick counties. Although there are no two-stage ditches yet in Southern Indiana, one is scheduled in Posey County this spring and another is slated to be in Vanderburgh, Warrick, or Spencer counties by this summer.
“The focus has been on the Wabash River and started in the Wabash River Watershed, but in the northern part of the state. As we have grown and developed this program, we have moved down south,” says Smith.
Smith says the Nature Conservancy is looking for landowners who are interested in learning more — the problem is enough people don’t know about it yet. The Alcoa Foundation has provided the finances to help construct the two-stage ditch, which will go in the Vanderburgh, Warrick, or Spencer County area.
“One of the big hurdles for farmers is that it takes up more land,” says Smith. “The farmer will typically lose about half an acre of total land on either side of the half-mile-long ditch. That may be a bit hard for them to take.”
Smith says the ideal site is where a farmer is already losing that area because of erosion and the banks are failing. “The advantage is they get a stabilized ditch system and don’t have to worry about losing more and more land,” he says.
For more information about the Nature Conservancy’s Southwest Indiana Project, call 812-437-3092 or visit nature.org/indiana.