Waterways – Agriculture

A grassed waterway is a shaped, graded channel planted with grass that carries runoff across a field at a speed that will not cut gullies, then releases it at a stable outlet. Jordan Excavating LLC installs and repairs grassed waterways for farms across central and southeast Indiana, from Decatur and Rush counties to Shelby, Bartholomew and Jennings.

Key Takeaways

• A grassed waterway is a broad, shallow, vegetated channel that moves concentrated runoff to a stable outlet without eroding the field. NRCS lists it as conservation practice 412.
• Indiana NRCS sizes waterways for the peak runoff of a 10-year, 24-hour storm, which brings about 3.7 to 4.7 inches of rain across the state.
• Most Indiana waterways are about 20 to 60 feet wide or more, depending on soils, slope and how much water the draw carries.
• Seed and temporary cover, such as straw mulch or erosion control netting, need to go in right after construction.
• NRCS EQIP may offer cost-share, and your local USDA Service Center can tell you whether your field qualifies.

How Do You Know If a Field Needs a Grassed Waterway?

The clearest sign is concentrated flow. If water gathers in the same draw every time it rains hard, and you keep seeing washed-out rows, rills that turn into gullies, or residue piled up at the bottom of the field, that is the kind of spot a waterway is built for. Indiana NRCS points to concentrated flow that keeps causing erosion, even with temporary cover, as the deciding factor. Common places we see this around Greensburg, Rushville and Shelbyville include:

• Draws between two hills that carry water every spring
• Low spots in crop fields that stay wet or flood after storms
• Ditch banks and tile outlets that have washed out
• Outlets for terraces, diversions and other conservation practices

If you have to slow down or steer around an eroded channel at planting or harvest, you are losing time and topsoil. A waterway fixes the channel so equipment can cross it.

How Is a Grassed Waterway Designed and Built?

Every waterway starts with the water. The channel has to carry the runoff from its drainage area without overtopping or cutting. Indiana NRCS designs for the peak runoff of a 10-year, 24-hour storm, and roughly 2 to 3 inches of that rain can run off depending on soils, cover and land use. Here is how we approach a typical job:

1. Walk the field to find where water enters, where it concentrates and where it can safely leave.
2. Shape a broad, shallow parabolic or trapezoidal channel to the planned width and grade with GPS-guided equipment.
3. Tie the waterway into a stable outlet such as a ditch, tile outlet or grade stabilization structure.
4. Smooth the side slopes so tractors, planters and combines can cross.
5. Seed right away and cover with straw mulch or erosion control netting until the grass takes hold.

When a waterway is part of an NRCS contract, the design follows the local Field Office Technical Guide, and we build to that plan.

What Does It Take to Maintain a Grassed Waterway?

NRCS lists a minimum expected life of 10 years for a grassed waterway, but only if the sod stays healthy. Most damage comes from equipment and herbicides, not from the water itself. A few habits keep a waterway working:

• Inspect after big storms and repair washouts or thin spots quickly.
• Mow to keep brush and trees out of the channel, but Indiana NRCS advises no mowing between April 1 and August 15 to protect nesting wildlife.
• Cross only when ground conditions allow, and avoid spraying the grass.
• Do not plant end rows along the sides of the waterway.
• Use reduced tillage, no-till or cover crops on the field above it to cut the sediment coming in.

When an older waterway fills with sediment or a gully starts cutting through it, we can reshape and reseed the channel instead of starting from scratch.

Is There Cost-Share for Grassed Waterways in Indiana?

Often there is help available. Grassed waterways are NRCS conservation practice 412, and conservation practices may be eligible for financial assistance through the Environmental Quality Incentives Program, or EQIP. According to Indiana NRCS, EQIP applications are accepted year-round, but funding is competitive and applications are ranked, with cutoff dates for each funding cycle. To start, contact your local USDA Service Center, where NRCS and FSA staff can check eligibility. You will need:

• An official tax ID
• A deed or lease showing you control the land
• An FSA farm number

If you are selected, you sign a contract, the practice is installed to NRCS standards, and payment is made after it is inspected. Your county soil and water conservation district is another good place to ask. We are glad to build from an NRCS design.

Frequently Asked Questions

What is a grassed waterway?
A grassed waterway is a shaped or graded channel planted with grass and other perennial plants. It carries concentrated runoff across a field at a speed that will not erode the soil and delivers it to a stable outlet. NRCS calls it conservation practice 412, and it is one of the oldest conservation practices used in Indiana.

How wide is a grassed waterway?
Most grassed waterways in Indiana are about 20 to 60 feet wide or more. Width depends on how much water the drainage area produces, how steep the field is, how stable the soil is and how dense the grass will be. Erodible soils and sparse vegetation call for a wider, larger channel to handle the same storm.

Can I drive farm equipment across a grassed waterway?
Yes. Waterways are built with broad, shallow parabolic or trapezoidal shapes so tractors, planters and combines can cross them. Cross when ground conditions allow, avoid making ruts and keep herbicide off the grass. Equipment and herbicide damage are the most common causes of waterway problems, and damaged areas should be repaired promptly.

When should a grassed waterway not be mowed?
Indiana NRCS recommends no mowing between April 1 and August 15 so nesting wildlife is not disturbed. Mowing outside that window keeps the grass healthy and stops brush and trees from moving in, which would reduce how much water the channel can carry. If your waterway was cost-shared, also check your contract terms.

Who installs grassed waterways in southeast Indiana?
Jordan Excavating LLC is based in Greensburg in Decatur County and installs grassed waterways across 20 central and southeast Indiana counties, including Bartholomew, Rush, Shelby, Franklin, Jennings, Ripley and Johnson. We are licensed and insured, use GPS-guided equipment, and can build from an NRCS design or help you plan the job.

Get A Free Estimate

If water is cutting through your fields, we will walk the site with you and lay out a waterway plan that fits your ground. Request a free estimate online or call us at (812) 371-6999.

Related services: Farm Pond Building | Fence Line Clearing | Commercial Drainage

Written by Cameron Jordan, owner of Jordan Excavating LLC, serving central and southeast Indiana for 10+ years. Last updated: October 22, 2026.

Sources: Indiana NRCS: Ask the Expert, Grassed Waterways | NRCS Grassed Waterway (412) Overview | Indiana NRCS EQIP