Press Releases

Water Quality Study Outlines Improvement Plan For Aliso Creek Watershed

County Executive Office - Press Release

FOR IMMEDIATE RELEASE
July 27, 2000

COUNTY OF ORANGE
WATER QUALITY STUDY OUTLINES
IMPROVEMENT PLAN FOR ALISO CREEK WATERSHED

Contacts: Larry Paul
County of Orange
Public Facilities &
Resources Department
(714) 834-5172
714.834.6203

Public Education Tops the List of Recommended Management Strategies

Santa Ana, CA (July 28, 2000) -- A comprehensive list of recommendations ranging from programs to educate the public about water quality and urban runoff to retrofitting existing drainage systems are among the management strategies proposed by the County to improve water quality within the Aliso Creek Watershed.

The recommendations are based on the findings of a two-year $152,000 study of the Aliso Creek area, a watershed that extends southwest from Portola Hills through Lake Forest, Mission Viejo, Laguna Hills, Laguna Niguel, Aliso Viejo and Laguna Beach.

The study, $114,000 of which was financed by a grant from the state, examined conditions within the 34.6-square-mile watershed and describes a creek -- and its associated features -- that is characterized by elevated bacteria counts, unstable aquatic life and ecological stress. High water temperatures were also noted downstream of developed portions of the watershed and may be a contributor to reduced plant life and animal species.

More than a dozen short- and long-term strategies for water-quality improvement are ranked within the study's recommendations and are proposed to be used by the County and affected cities in planning their future water quality efforts to restore the creek and protect the watershed's beneficial uses.

Study results and findings will also be incorporated into a larger watershed management study of Aliso Creek now being prepared by the U.S. Army Corps of Engineers.

"Of the management strategies identified, public education is of the highest priority and can provide the broadest and most immediate impact," said Vicki Wilson, director of the Public Facilities & Resources Department. "The County has taken several steps to improve water quality in the Aliso Creek area, including diverting urban runoff to a sewage-treatment plant. But we can only be successful in our efforts with the support of those who live in the watershed area as well as those who visit the local parks. Educating the public on the poor condition of the watershed and the steps they can take to help improve water quality is critical to our overall effort."

Other recommendations, including such long-term and costly approaches as constructing an on-site biofiltration facility and building one or more water-quality wetland areas in the lower Aliso Creek watershed, are also listed as management strategies in this scientific study.

The County began the Aliso Creek Water Quality Planning Study in late 1997 by examining existing resource materials and developing extensive maps of the watershed. The maps delineate the major tributaries, sub-basins and physical features in the watershed, general land uses, land ownership and the major water and sewer infrastructure in the area, all of which provided a base for experts to begin their detailed analysis.

An assessment of aquatic life at four sites in Aliso Creek and two in Sulfur Creek were also performed and all test-area habitats were found to be biologically unstable. Studies also showed evidence of ecological stress.

Elevated bacteria concentrations originating from several locations along the creek were also noted. In addition, higher water temperatures, like those found in more developed areas, were logged along Aliso Creek and may have a negative influence on water quality and creek biology. One of the recommended strategies is to restore shaded areas along the waterway.

As part of the study, the County also performed a recreational-use analysis and determined water quality improvements could possibly generate a benefit valued at $600,000 annually at the three major recreational parks within the watershed, Laguna Niguel Regional Park, Aliso and Wood Canyons Regional Park, and Aliso Beach Park.

Representatives from impacted cities, local and state agencies, and environmentalists participated in the two-year effort. As part of this outreach, a technical advisory committee was formed where results of the water-quality studies were discussed and input solicited on study direction.

The Aliso Creek Watershed has been identified by the San Diego Regional Water Quality Control Board as a target watershed for priority water-quality protection efforts, with the lower mile of the creek designated as "impaired" under the federal Clean Water Act due to elevated bacteria levels.

The Aliso Creek Watershed effort is the first of its kind in the County. Similar watershed restoration studies are underway for the San Juan Creek Watershed and the San Diego Creek/Newport Bay Watershed.