Aging corrugated metal pipes are being replaced throughout the unincorporated area with appropriately sized pipes, arches or other structures. New pipes are outfitted with erosion-reducing concrete headwalls and outlet energy dissipation. 

New culverts on fish-bearing streams are designed and permitted in accordance with Department of Fish and Game and National Marine Fisheries Service guidelines to ensure fish passage.

new culvert
This new culvert drains onto large rip rap that was already on the slope. Rice straw was immediately applied as mulch for the backfill to prevent surface erosion and help native plants re-establish.
new culvert
This is a new 18" plastic pipe with a Pacheco flume attached to the outlet. The flume prevents splash erosion from occurring below the pipe outlet. The flumes are custom-made by the Road Maintenance Division to fit any culvert.