Vegetating other areas of high erosion hazard Waterways Soils in areas of high erosion hazard such as waterways and sites subject to wind erosion need to be stabilized by vegetation and or mechanical structures Most areas can be successfully vegetated by using proper agronomic and engineering practices Vegetating other areas of high erosion hazard Good management is needed to maintain the vegetation Vegetating other areas of high erosion hazard Gullies are controlled by Diverting water from them Grading the banks to stable slopes 2 1 or 3 1 Establishing vegetation Fence out animals Vegetated waterways can prevent the formation of gullies if the are properly maintained 1 Vegetating other areas of high erosion hazard Diversion Terraces Diver water Size shape and length to handle 10 year 24 hour runoff Build waterway and vegetate before terraces V shape parabolic or trapezoidal Vegetating other areas of high erosion hazard Pond banks and stream banks need protection from waves and running water Wind breaks are established primarily to enhance the ecological environment for people and domestic livestock Shelterbelts are established for the purpose of reducing wind velocity and wind erosion on cropland Vegetating other areas of high erosion hazard Massive efforts have been expended to establish shelterbelts and windbreaks in the Great Plains where wind erosion and dust storms are a threat during every season of low rainfall Sand Dunes Occur around ocean and lake shorelines and in land in arid and sandy regions They can be stabilized with vegetation in several years Careful management is essential even after dunes have been stabilized 2 Design for a grassed waterway Circular 1225 Most farm plans include grassed waterways as part of their design The wide shallow sod lined channels safely dispose of surface water from heavy rains and prevent the formation of gullies or without eroding soil Design for a grassed waterway Circular 1225 Land used for water ways is not wasted The production of forage or the use of the land as a wildlife habitat should be secondary to the proper functioning of the waterway Design for a grassed waterway Circular 1225 Grassed waterway in Illinois Best time to establish in Illinois is mid summer Use area for small grain harvest the establish waterway From 1970 to 1980 800 miles of grassed waterways were built on Illinois farms each year How many removed 3 Establishment of Grass Seed Grassed Waterways Uses To drain terraces or as diversions Dispose of water collected in road ditches Stabilize a natural draw that is eroding Stabilize a natural draw to which additional runoff water is being added by contours or terraces Grassed Waterways Should be built as part of a total conservation program Requirements Must have enough soil to establish and maintain a stand of grass Stable outlet is essential Tile drainage may be required beneath the water waterway 4 Hydrologic Design Rainfall 24 hour maximum in 10 years Hydrologic soil group A sand B C and D clay Curve number Runoff Watershed slope total land Flat 0 2 moderate 3 to 7 steep 7 Peak flow Shape and dimension General layout Drainage area Shape Flow velocity Capacity Waterway design Construction Tile 5 6 7
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