US Army Corps of Engineers
Los Angeles District

Riparian Ecosystem Restoration Plan (2004)


Watershed Factors

The restoration potential of each riparian reach was classified in terms of the following three watershed factors:

  • Geomorphic Zones of the Watershed: The geomorphic zones reflect fundamental geomorphic characteristics of each reach under "equilibrium" conditions. Five geomorphic zones were identified for each riparian reach based on topographic maps, the maps and descriptions provided in the county soil survey, and geologic maps and reports on Orange County and the region.
  • Level of Restoration Effort: The level of effort designated for each reach represents the amount of work necessary to achieve conditions defined by each reach's restoration template. Level of effort was intended to serve as tool for planners based on the assumption that limited resources or potential sites would be available for restoration, or limited potential sites available to offset certain types of impacts. The level of restoration effort for each riparian reach was assigned using aerial photography, baseline assessment data, knowledge of each riparian reach acquired during baseline assessment field sampling, and field verification.
  • Restoration Templates: Restoration templates were developed to represent the best possible restoration target, given the potential natural patterns expected for the Geomorphic Zone. Restoration templates reflect the extent to which the fundamental equilibrium conditions could be re-established within each reach. These templates were developed by analyzing 50 riparian reach segments to establish specific restoration criteria in terms of channel cross section and form, the scale of terraces present, and characteristic vegetation types.
GIS datasets for each watershed factor defined above can be viewed using the map below (best viewed using Chrome or Firefox):