Fishbeck was responsible for the evaluation of the existing culvert crossing under the Nichols Arb service road. It was determined that a small box culvert was the best option for replacement, providing enough hydraulic capacity for a 100-year storm event, reducing outlet velocities, and ensure additional capacity should sediment collection continue from erosion within the ravine.
The existing 24-inch culvert and headwall were removed and replaced with a 30-foot long 8-foot by 3-foot precast concrete box culvert with a headwall and wingwall. An existing concrete weir was stabilized and a fieldstone spillway was constructed upstream of the culvert. A cascading rock channel was also added upstream of the culvert. Downstream of the culvert, a plunge pool with riprap was constructed to preserve the existing channel from erosion. These measures were taken to remove the existing erosion problem adjacent to the river.
The scope of services included a topographical survey, EGLE permitting, coordination of geotechnical investigation, and the preparation of construction drawings and specifications.
