Aliso Creek Mainstem Riparian Restoration

Location: Orange County

Project Type: Restoration

Status: Current

Habitat Type: Erosion/Sedimentation, Exotics Control, Freshwater Wetland, Riparian, Water Quality

Cost: $45,000,000

Acres: 4236

Stream Miles: 7

Assembly District: 74

Senate District: 37

Congressional District: 48

Project Lead/Grantee: County of Orange (Marilyn Thoms, 714-834-2352)

Project Lead Website:

This project involves ecosystem restoration in a seven-mile reach of Aliso Creek and 1,000 feet of the Wood Canyon tributary, located in southern Orange County. The lower reaches of Aliso Creek and its tributary, Wood Canyon Creek, are located within a County-owned Wilderness Park and support high quality riparian habitat.

The Aliso Creek watershed suffers from a number of problems related to urbanization of the watershed, including creek instability, degraded water quality, loss of fish and wildlife habitat, and flooding damages. Continued degradation of the creek threatens to degrade or destroy the riparian habitat in Aliso and Wood Canyon Creeks. This project’s restoration activities will focus on revitalization of the riparian vegetation community; restoration of natural processes, channel stabilization, and reduction of erosion and flood risk. All non-native species, with the exception of about 1 acre at the mouth of the creek, have been removed and are in maintenance. The Corps Feasibility Study should be completed in 2016, and design of the selected alternative to follow shortly thereafter.