The ditches are a major component of the state's overall drainage system. As many as 20,000 miles of man-made ditches carry water runoff from farm fields into rivers and streams.
They also carry soil and agricultural chemicals from the fields. Some ditches are so polluted they're included on the state's impaired waters list. The study, scheduled to be released soon, surveyed a variety of governmental units with jurisdiction over ditches.
Mark Ten Eyck with the Minnesota Center for Environmental Advocacy was part of the group which put the report together. He points to one particular problem.
"A significant amount of the drainage ditches built in Minnesota since 1977 do not have the buffer strips required by law," says Ten Eyck.
“We are seeing from the reporting that there are probably some areas where there's supposed to be a buffer that isn't there.”State Representative Rick Hansen
Ten Eyck says state law requires a 16 1/2 foot grass buffer on both sides of certain ditches. He says it helps trap air and water borne soil, preventing the particles from moving downstream. He says buffers also make good wildlife habitat.
The study found that just over 2100 miles of ditch in the state should have the buffer. It found more than a quarter of that total, about 600 miles, doesn't have the strip.
State Representative Rick Hansen sponsored the legislation which funded the study. He says the number of non-compliant ditches was higher than expected.
"We are seeing from the reporting that there are probably some areas where there's supposed to be a buffer that isn't there," says Hansen. "How do we get the buffer there to meet the law and to start getting the benefits of having vegetative buffer strips along public drainage ditches?"
Some people want the state to force local jurisdictions to install the buffers. Hansen disagrees.
"They may say let's just go out there right now and go in with the hammer," says Hansen. "But I don't think that we have the capacity to do that right now, and I'm not sure if it would be the most effective way of dealing with some complex issues."
Hansen says the voluntary approach is working. The number of ditches without buffers is falling. A 1987 study found fewer than half met the standard. Study group member Thom Petersen of the Minnesota Farmer's Union also says the voluntary approach is best.
"I think in general farmers want to do the right thing," says Petersen. "They just want to also make sure they're getting compensated for it or they're getting some help in doing the project."
Petersen says buffers means less revenue for farmers since they take crop land out of production. He believes more farmers would install them if they knew about various state and federal programs which help pay for conservation work.
Some people believe the state may be forced to abandon it's cooperative approach. Greg Roiger was part of the study, he's a soil and water conservation district supervisor from Brown County. Roiger says he wouldn't be surprised if some environmental group takes legal action to force government to make sure the buffers are built.
"The law still states that there are a number of ditches that require buffers to have them on them and they're not there," says Roiger. "And that certainly could be a decision by some people to talk about and to take that next step."
The study group plans to continue working on the issue in the months ahead. There are several things they'd like to see done. Among them, educational programs for local drainage officials on exactly what state law requires and how best to accomplish it.