Minnesota MNDOT Erosion Control Products

Solmax DOT Standard Specification Product Chart (click image to expand)

Minnesota MNDOT - Erosion Control Methods

Minnesota job sites span glacial tills, lakebed clays, sandy outwash, peat pockets, and steep river bluffs, plus the wave-exposed North Shore of Lake Superior. Layer on deep frost, long freeze–thaw seasons, spring snowmelt and ice-out, and gully-washing summer thunderstorms, and freshly graded slopes can ravel fast while ditches cut and deliver sediment to culverts and streams. MnDOT’s playbook stacks controls that (1) protect bare soil, (2) slow and spread runoff, and (3) capture sediment until vegetation takes over.

Rolled erosion control products (RECPs). On new embankments, slope repairs, and roadside swales, crews install straw, excelsior, coconut/coir, or blended blankets to shield soil and seed from rain splash, wind, and meltwater. Straw blankets suit short, gentle slopes and low-velocity swales; heavier coir or straw-coir mats handle longer grades and higher shear common during snowmelt and summer downpours. Blankets are trenched at the crest and toe, overlapped shingle-style, and stapled per manufacturer patterns—with extra anchoring on windy prairie corridors and the North Shore. Along lakes and streams, coir logs toe-in blanket edges and hold the line until vegetation roots.

Turf-reinforcement mats (TRMs). Where velocities exceed temporary blanket limits—steep ditch sections, culvert outlets, sharp bends, and drawdown areas—synthetic TRMs provide a long-life scaffold. Once grass roots knit through, the vegetated composite resists repeated storm events and ice-out better than bare soil and can reduce reliance on continuous riprap in constrained rights-of-way.

Hydraulic mulches and soil binders. Irregular cuts, rocky sections, and broad slopes are treated with hydraulic applications: hydroseed with hydromulch, bonded fiber matrix (BFM), or flexible growth media (FGM). BFMs form a breathable crust that resists sheet flow yet allows germination—ideal for quick cover between storm windows. Where straw mulch is used, it’s crimped into the surface and locked with tackifier or polymer binder so it won’t blow or float during spring thaw.

Slope interrupters and perimeter controls. Fiber rolls (wattles) and compost filter socks, placed on contour, break long slope lengths into short runs, slowing water and trapping sediment before rills form. At the disturbance boundary, silt fence excels in fine-grained tills when trenched and backfilled correctly; on stony shoulders or tight urban footprints, heavier filter socks provide stability and easy maintenance. The goal is to intercept sheet flow high on the slope so water never gains erosive energy.

Check structures and channels. Temporary rock or wattle check dams in construction ditches cut velocities and drop out sediment. Spacing is set so each crest ponds to the toe of the next, creating stair-step energy dissipation. At outfalls and aprons, crews pair RECPs or TRMs with riprap over an appropriate filter layer; coir logs at the toe keep edges tight until vegetation takes hold. In very high-shear zones or where water levels swing, articulated concrete block mats add durability while allowing vegetation in the cells.

Inlet protection and track-out control. Curb socks, drop-inlet inserts, and gravel rings around grates keep sediment out of storm systems during grading and paving. Stabilized construction exits—coarse stone over geotextile—limit mud tracked onto public roads; street sweeping backs them up where sticky clays cling to tires.

Basins, traps, stockpiles, and drains. Sediment basins or traps intercept runoff from disturbed areas and provide settling time before discharge; temporary slope drains safely convey water down steep fills during early phases. Topsoil stockpiles are promptly seeded and mulched or covered, with perimeter wattles or fence to contain fines.

Seasonal strategy and upkeep. With short growing windows, dormant seeding in late fall and early-spring seeding windows are common. Cold-hardy, region-appropriate mixes are matched to aspect and moisture; coir-rich blankets and higher mulch rates help on sunny, wind-exposed slopes. After storms, melt, or ice-out, crews repair tears, reset stakes, clean inlet devices, remove accumulated sediment (often at half-height), and reseed bare spots. Temporary controls come out once vegetation is dense and slopes and channels are stable.

Bottom line: on MnDOT projects, erosion control isn’t a single product—it’s a layered system. Blankets, TRMs, hydraulic mulches, wattles, silt fence, check dams, inlet protection, basins, and stabilized exits work together to tame snowmelt and thunderstorms, protect waterways, and give vegetation the foothold it needs to lock Minnesota’s soils in place.

Minnesota MNDOT