10-1Q490: Markleeville Storm Emergency Repairs

10-1Q490: Markleeville Storm Emergency Repairs

The California Department of Transportation (Caltrans) proposes an emergency Director’s Order project to immediately repair damages near the community of Markleeville, along State Route (SR) 89, from post mile (PM) 14.9 to 17.3, in Alpine County. On August 3, 2022, an extreme storm event inundated Millberry Creek that runs adjacent to SR-89, and the surrounding areas, causing severe damages to the roadway, roadside ditches, and drainage facilities. Debris and sediment were deposited approximately 2-6 feet thick at various locations along the creek, roadway, and drainages. Several headwalls and culvert pipes were severely damaged. The culvert at PM 15.21 washed downstream, leaving SR-89 unsupported, and one of the main access routes for the Markleeville community, unsafe for travel. The scope of work includes installing a temporary creek crossing, clearing debris and sediment, reestablishing drainage ditches, pavement repairs, placing shoulder backing, placing Rock Slope Protection, and replacing culverts and headwalls. At PMs 14.91, 14.99, 15.05, and 15.15 the existing 18” Corrugated Steel Pipes (CSP) will be replaced with 24” CSPs and new concrete headwalls will be installed at the inlets. At PM 15.21 the washed out 48” CSP will be replaced with a 96” CSP. At PM 15.22 the existing 24” CSP will be replaced with a new 24” CSP and a new concrete headwall will be installed. The purpose of this project is to immediately rectify structural and drainage damages caused by the extreme storm event and to re-open SR-89 to the traveling public. The project is needed to prevent the loss or impairment of life, property, or essential public services.

Markleeville

Alpine

Northern California

Alpine