Slope & Erosion Control in Kansas City, MO

Slope and erosion control is the work we do where a plain lawn seeding would wash away. Builders call us as erosion control contractors for permit work, and homeowners call when a bank keeps sliding into the yard; our erosion control services cover both. In Kansas City, that means a lot of ground. The city sits on bluffs above the Missouri and Kansas rivers, its center is bowl-shaped, and limestone and bedrock cliffs ring it to the north and south. Older neighborhoods back onto wooded ravines, and newer subdivisions are cut into rolling loess hills with long side slopes, swales and detention basins. When those surfaces are bare and a spring thunderstorm rolls through, soil moves.

Why local slopes wash

Kansas City's rainiest months are May and June, each averaging more than five inches at the airport, and precipitation stays high through August. The silty loess soils that cover much of the upland are easy to dig and easy to wash. The USDA rates Sibley soils, a typical local series, as having medium to moderately rapid runoff even on slopes of 2 to 14 percent. Once the grass and dark topsoil are gone, rain hits the silty clay loam subsoil, seals the surface and runs off, carrying fine silt with it. Small rills turn into gullies within a season.

Choosing the right cover

Every slope gets matched to a material based on its steepness, its length, and how much water flows across it:

• Standard hydromulch: wood fiber mulch with seed and tackifier for gentle banks and the edges of lawns.
• Heavier hydromulch and bonded fiber matrix (BFM): a thicker spray with stronger binders that sets into a crust-like mat. It holds on steeper banks where a blanket would be hard to anchor, and it goes on without anyone walking the slope.
• Straw erosion control blankets: straw stitched into netting, rolled down the slope and stapled in place over the seed. Good for moderate slopes and swales.
• Straw-coir and coir blankets: longer-lasting coconut fiber for steeper banks, channels and spots where grass will take more than one season to fill in.

In ditches and swales, where water concentrates, we roll blankets in the direction of flow, overlap them shingle-style and trench the top edge in so water cannot get underneath.

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Seed that holds

On mowed slopes we use the same tall fescue blends as our lawns. On banks that will not be mowed, we can use a lower-maintenance mix with deeper-rooted grasses. Many local soils, Sibley included, formed under tall prairie grasses, and native warm-season grasses can do well on a sunny bank where mowing is unsafe. We discuss the tradeoffs with you: native stands are slower to establish and look rougher in the first year.

Creek banks and drainage problems

If your slope runs down to a creek, be aware of the rules. The City of Liberty, for example, notes that most drainage problems on private property are the owner's responsibility under Missouri's modified common enemy doctrine, and that the U.S. Army Corps of Engineers has jurisdiction over waterways, so owners should check permit requirements before any creek stabilization. We handle the upland slope, grading, seeding and blankets. Work in the channel itself may need permits and an engineer, and we will tell you when a job crosses that line.

Fix the water first

No blanket survives a downspout aimed at it. Before we cover a slope, we track down every source of runoff that reaches it: roofs, driveways, a neighbor's yard, a street inlet that overflows. Sometimes the fix is a swale at the top of the slope, a buried downspout extension, or regrading so water spreads out instead of concentrating. That part of the job is handled by our grading crew and shows up as its own line on the estimate.

What to expect afterward

Blankets and BFM look rough at first. Grass comes up through the netting over a few weeks, and the material breaks down over one or more seasons depending on the product. Keep people and mowers off until the grass is established. After big storms in the first few months, walk the slope and call us if you see a rill starting. Small repairs early prevent a bigger one later.