Big Tree Creek Stormwater Compliance Project (Lake or Streambed Alteration Agreement No. 1600-2015-0218-R2)

Big Tree Creek Stormwater Compliance Project (Lake or Streambed Alteration Agreement No. 1600-2015-0218-R2)

The project will widen the existing roadway on both sides to provide 8-foot paved shoulders, a 10-foot paved gutter on the left side of the hwy and a 3-foot paved gutter on the right side of the hwy to accommodate storage area for snow removal. The scope of work includes construction of approx. 800 linear feet of retaining walls and 2,400 linear feet of concrete barrier located on he south side of the hwy within the riparian area of Big Tree Creek. Temporary reinforced silt fence along the entire length of the project to assure will be installed to avoid additional impacts to the Creek. The new embankment will be keyed into the existing slope and compacted in layers to ensure stability. The existing pavement will be overlaid with asphalt concrete. Existing drainage facilities will be modified along with the addition of new drainage facilities. The drainage facilities will be constructed as traction sand traps. The traction sand traps will temporarily detain runoff and allow traction sand that was previously applied to snowy or icy roads to settle out. These traction sand traps are the storm water management plan approved permanent treatment best management plans for statewide application to address sand which is the non-storm water discharge of concern. Overhead power and underground telephone facilities will require relocation. There are also sewer facilities in the area but relocation is not anticipated. The project will upgrade the existing 18-inch diameter corrugated steel pipe (CSP) or concrete. The existing drainage inlets located in the existing drainage ditch that parallels the hwy on the north side will be removed and replaced with sand trap type drainage inlets in the new ditch line.

Calaveras