Specifications include, but are not limited to: Minimize disturbance to the natural system and surrounding land and install sandbag dams in the stream and use a pump, with riprap placed at the discharge, to convey the water around the excavation, if necessary. Excavate the culvert area; remove and dispose of old culvert. The bottom width of the culvert trench should be twice the width of the culvert, with sidewalls no steeper than 1:1. Excavate 10 feet downstream of the culvert discharge to a depth of 18” for riprap. Use erosion control precautions. Lay pipe up slope, starting at outlet end. The longitudinal profile should be set at the same slope as the natural stream gradient. Where possible, a minimum of 18”-24” of fill over a culvert is recommended. Place 12 inch minus riprap in the excavated outlet area tamping it level with the stream bottom. Hydroseed or seed and mulch, all disturbed areas. The chosen Contractor will work under the direction of the Road Foreman. Invoicing shall be for work satisfactorily completed and paid per lump sum bid.
