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Accelerated soil erosion and the sedimentation caused by it pose serious problems for the construction industry and state and local agencies. Runoff from construction sites has high sediment loads which may contain various pollutants, including oil, chemicals, and soil wastes. Natural erosion in ditches and along roadways may result in sedimentation that may result in costly damage to water and land. Drainage channels, culverts, and storm sewers may be filled and plugged by sediment, resulting in frequent and costly maintenance. This report addresses those problems and outlines methods for controlling erosion both during and after construction. Structural and vegetative practices for reducing sedimentation are given, and turf establishment techniques for native grasses and wildflowers are discussed. Information regarding the National Pollution Discharge Elimination System (NPDES) Storm Water Permit Requirements is also given.

The goal of this project is to develop a sub-soiling regimen that will enhance and be compatible with existing erosion control measures. This project is important in minimizing the effect of construction-induced compaction on the urban and rural landscape. This activity, if successful, will become a building block for use in Best Management Practices (BMPs) that will ensure full vegetative growth post construction, and save on the cost of reapplication of erosion control measures. For a good comparative study, several sites were selected for typical slope and soil type. The study shows that there are low cost benefits to deep tillage of ROW. Heavy clay soils are problematic in that improvements in infiltration could not be detected after a single tillage operation. In lighter sandy soils, the benefits of tillage are such that significant increases in infiltration can be gained following a single pass tillage operation. The differences in tillage implement used could not be detected. The post-tillage aesthetic appeal when using a non-inverting plow (Kongskilde Paraplow) was apparent in this study. The vegetation was largely undisturbed following tillage, and this would be beneficial in preventing erosion on slopes. The ripper and the DMI inverted more soil, and therefore the tillage operation was less appealing to motorists. The relatively low cost of ownership and operation for the tillage is overshadowed by the high land cost when new roads are constructed. Tillage would be beneficial on lighter soils, however the "utility congestion" that is likely in such a scenario would make machinery management difficult.

Unsafe conditions exist on aggregate surfaced shoulders when material erodes either from vehicular means or from erosion caused by wind, rain, and other forces. Most of the material is unrecoverable and therefore wasted. This adds to the labor, equipment, and additional costs of maintaining the shoulder. The following results are from a study sponsored by the Mn/DOT Maintenance Operations Research Fund and the Mn/DOT Office of Materials Based upon input from maintenance supervisors; the project monitored the field performance of several aggregates and stabilization treatments during a 2-year evaluation period. Materials were evaluated along straight sections, vertical, and horizontal curves where AADT conditions varied from 3,000 to 25,000. Aggregate gradation, shoulder drop-off, and erosion were monitored. Measurements also included shoulder cross slope and photo documentation of shoulder condition.

While building highways, heavy machinery passes over the ground next to the road many times, severely compacting the soil. This results in poor drainage, inhibits the growth of vegetation and causes erosion. Managing the storm water runoff from highways and compacted rights of way may require the purchase of additional land, which is often a significant expense in construction projects. Holding ponds built to manage storm water runoff are also expensive and need regular maintenance.