DESERT KNOLLS WASH INTERCEPTOR SUSTAINABLE RELOCATION

摘要

The South Apple Valley Interceptor was constructed in 1981 and crosses the Desert Knolls Wash several times in the vicinity of the Lewis Center for Educational Research (Lewis Center) in Apple Valley, CA. The original interceptor design within the wash area was inadequate to protect the pipe from major storm events with scour. On December 24, 2017 a portion of one crossing (15-inch PVC) was totally exposed and floated during a significant rain event. An emergency condition assessment was performed on the existing interceptor with the following recommendations:1. Develop a new alignment that removes the South Apple Valley Interceptor from the Desert Knolls Wash and minimizes conflict with the future San Bernardino County Flood Control District Desert Knolls Wash Phase III Project in this area.2. Explore options to remove grit (sand and rocks) from entering the new 16-inch double barrel siphon beneath the Mojave River.3. Provide for relocated flow monitoring and sampling.This paper covers the emergency condition assessment, design, and construction practices that will help ensure a minimum of 100-year design life and long term sustainability including:1. Corrosion resistant precast polymer manholes and bases.2. Innovative grit collection facility constructed with precast polymer manholes with stainless steel slide gates and bypass system. The grit facility protects a relatively new HDD 16-inch double barrel crossing of the Mojave River in Apple Valley, California from rocks, sand, and debris.3. PVC pipe.