California Department of Fish and Wildlife, Bay Delta Region 3
State Route 29 Culvert Permanent Restoration Project (EA 04-0Q820) (Notification of Lake or Streambed Alteration, No. EPIMS-NAP-26858-R3)
NOE - Notice of Exemption
The Project is limited to the SR-29 Permanent Culvert Restoration Project. Caltrans will rehabilitate and repair an existing 42-inch alternative pipe culvert (APC) along SR 29 from PM 11.6 to PM 13.0. The repair/rehabilitation will include replacement of the existing APC and other damaged drainage structures. The existing 42-inch APC drains stormwater runoff from the SR-29 and Trancas Street interchange south toward Napa Creek. Open trench excavations will remove and replace the existing culvert north of Napa Creek, initiating at the existing headwall and extending approximately 35 feet to the north and upslope. The existing headwall will remain in place, the culvert will be excavated, replaced, and backfilled. Open trench excavations will include complete removal of the existing culvert and 7.5-foot wide trenching up to 15 feet deep where necessary. Shoring will be used at locations where trench depth is more than 5 feet. Tree removal will be performed where open trenching or pit excavations interfere with roots systems or trees occur within the direct path of the trench. Three riparian trees located within the path of the planned trench excavation will be removed.