OCWD Prado Basin Sediment Management Project
Focus:
Restoration Services
Challenges
OCWD owns 2,150 acres behind Prado Dam in Riverside County, known as the Prado Basin. They manage 465 acres of wetlands within this area. To address the problem of sediment buildup behind Prado Dam, which was reducing water storage capacity, OCWD and the US Army Corps of Engineers (LA District) worked together to temporarily hold back water at the dam. This led to the creation of the Prado Basin Sediment Management Demonstration Project (SMDP).
As part of an agreement with the California Department of Fish and Wildlife, OCWD started a Sediment Demonstration Project on a 14-acre site along the Santa Ana River, about 1.3 miles upstream of Prado Dam. This project included a 20-acre area for dewatering and storage, with four acres planted with native riparian habitat to offset any impacts from the ongoing operations of the Prado Wetlands.
The project was divided into two sections: Site 1 and Site 2. Site 1, a four-acre plot in the northeast corner of Pheasant Field, where vegetation was cleared, and native plants were added with an irrigation system, and Site 2, which contained existing habitat patches.
Innovative Solutions
Endemic Environmental Services carried out a native plant restoration project in the Prado Basin.
At Site 1, we planted around 4,000 container plants and installed a drip irrigation system connected to a large water storage tank provided by OCWD. Endemic purchased all the plants and irrigation materials for this site. We also placed deep pole cuttings of Fremont’s cottonwood, black willow, and mule fat throughout the area.
We designed and installed an above-ground filtered drip irrigation system at Site 1 to ensure that each of the 4,000 plants gets 1 gallon of water within a 2-hour period. The system includes cam locks at the tank for a small trash pump to run, brass ball valves to control the flow, and two in-line filters to prevent clogging. Endemic was responsible for all the irrigation system materials.
We also provided a 90-day maintenance period for Site 1, which included weeding, repairing the irrigation system, and watering for the first 30 days.
At Site 2, Endemic oversaw the planting of 500 long pole cuttings of mule fat, willows, and cottonwoods. The cuttings, provided by OCWD, were planted at a depth of about 5 to 7 feet, reaching groundwater and watered in. They were scattered across the site, with the final placement approved by OCWD staff.
Project Details
Location
Riverside County
Status
Complete - 2021