311 RIPRAP DITCHES
From MDOT Policy Manual
- Construct riprap ditches and riprap ditches with capping.
- 311.03.01 Excavation. Excavate to the specified line and grade. Ensure that ditch sides and bottom are smooth and firm, free from protruding objects that would damage the geotextile, and constructed in an acceptable manner. For excavated material, refer to 402.03.01.
- 311.03.02 Geotextile Placement. Place geotextile on the prepared subgrade with the adjacent edges overlapped at least 2 ft. Replace or repair damaged geotextile as directed.
- 311.03.03 Riprap Placement. Place stones by mechanical or other acceptable methods to produce a reasonably graded mass of stone. Methods that cause extensive segregation are unacceptable. Place the riprap to the specified depth.
- 311.03.04 Backfill. Backfill any excavation voids existing along the edges and ends of the placed riprap. Use suitable material to blend in with contiguous slopes, ditch lines, and existing ground. Cap riprap placed in the clear recovery area with a layer of 2 to 4 in. stone.
311.04 MEASUREMENT AND PAYMENT.
- The payment will be full compensation for all excavation, geotextile, stone, backfill, disposal of excess material, and for all material, labor, equipment, tools, and incidentals necessary to complete the work.
- 311.04.01 Riprap Ditches and Riprap Ditches with Capping will be measured and paid for at the Contract unit price per square yard of finished surface.
- 311.04.02 Bottom Cutoff Walls and Side Cutoff Walls will be measured and paid for at the Contract unit price per linear foot.