SCH Number 2021030428

Project Info

Title

Vallecitos Channel Maintenance Project

Description

The Vallecitos Channel is a critical component of ACWD's water supply system. The channel is an engineered, unlined, earthen trapezoidal channel that extends nearly 12,000 linear feet from the California Department of Water Resources (DWR) South Bay Aqueduct (SBA) turnout in the upper watershed to Vallecitos Creek near Vallecitos Lane in the lower watershed. The Project area extends from the head of the channel where the SBA emergency culvert outlet is located and extends downstream 7,980 feet. Under existing conditions, the channel requires maintenance. Several locations have experienced severe streambank erosion and bank sheering, thereby reducing the right-of-way width and rendering ACWD's maintenance road impassable. In addition, dense emergent vegetation obstructs flow in several portions of the channel, deflecting flow horizontally, exacerbating bank erosion and resulting in localized flooding. The Project will address bank erosion along Vallecitos Channel by implementing the following treatments: vegetation and sediment management, bioengineering treatments, partial bank rock slope protection (RSP), full bank RSP, and in-kind grouted RSP replacement at drop structures. The Project also includes upland drainage improvements and riparian/wetland habitat enhancement in portions of the channel. Project construction is anticipated to occur between July 2021 and October 2021 and require approximately 13 weeks for construction activities.

5 documents in project