This is the time of year when harvest begins, and farmers become aware of where erosion and gullying is under way in their fields and needs to be addressed.
The remedy is often installing grassed waterways — those green stripes located in the middle of certain fields.
Grassed waterways are like a natural Band-Aid, healing the land from the gully that was once there.
Grassed waterways are like nature’s reminder to us that tearing up the whole field should have been more carefully managed by the operator.
Grassed waterways are like interstate highways where field runoff water jumps on the grassed “on ramp” to the downhill one-way express to a larger highway of water flow.
(I have actually witnessed people canoe down their field’s grassed waterways after heavy rains. I guess that would be multiple use or value added agriculture!)
And I have also seen unmowed waterways sprouting grass clumps that force the water to go to the outside of the grassed waterway and flow downhill, cutting new gullies.
Waterways should be mowed and grasses kept relatively short for ease of water to remain within the grassy area.
Building grassed waterways should be done with care. Let’s start at the top end.
Is there additional flow coming from an upper field or from a woods or from across the road through a road culvert? If so, this flow needs to be accounted for and captured. The reason is, it will cause low flow wet conditions that can cause ruts when you cross it. Steering the water from the road ditch or culvert into a tile along the waterway is key.
How wide should the waterway be? Usually, they are designed to be 30- to 40-feet wide, depending on grade and length. The shape can be dish-shaped or trapezoidal. (I can’t believe I got to use that word in a sentence.)
How long should they waterway be? Long enough to solve the problem.
During construction, some type of in-channel check dams help slow water flow and help with seeding success.
Where do we end the waterway? Most often at the edge of the field.
But a common mistake is a waterway that ends at the edge of the field and water then flows down over an embankment to a ditch, ravine, or stream. When this happens a new gully will form without some sort of drop structure to lower the water gently into the receiving system.
Typical drop structures consist of rock chutes, weirs, wooden structures, catch basins, concrete block drops, concrete pillows. All have been installed to perform this needed function. When not utilized, a guaranteed erosion problem will begin and start the gullying process all over again.
Junk dumps are not recommended, as they are temporary at best. Stoned bottoms have been used in higher gradient waterways.
Funding can be available to supplement the cost of grassed waterways through two USDA programs.
EQIP is one. It stands for Environmental Quality Incentive Program administered through NRCS. CRP is also one. It stands for Conservation Reserve Program administered through the Farm Service Agency. Each program has eligibility requirements and each has different payment calculations.
Remember, if you participate in the USDA Farm Service Agency programs, they will take off the waterway acreage from the “cropable” acreage of a field unless the waterway is in a federal program like the Conservation Reserve Program.
The cost of installation of the grassed waterway maybe deductible from your farm tax situation since it is a conservation practice and part of a conservation plan. Check with your accountant for advice.
County auditors may vary as to their view of evaluating grassed waterway strips for property tax determinations. Your guess is as good as mine on this one.
Farmers who use grassed waterways should be thanked by society for solving a problem that normally would generate sediment in streams, culverts, ditches, ponds, or lakes.
The next time you are out driving around, watch for those big, green Band-Aids.