Dana Point Treats Urban Runoff to Clean Up Beaches

The City of Dana Point won the Grand Prize for this project in the Planning and Environmental Quality category of the 2007 Helen Putnam Award for Excellence program. For more information about the award program, visit www.cacities.org/helenputnam.

For several years, the coastal community of Dana Point has implemented comprehensive and aggressive programs to prevent polluted water runoff from reaching storm drains, creeks, waterways and beaches. These programs, referred to as “source control” because they are undertaken at the pollution’s source, include weekly street sweeping, education and outreach, inspections, inlet filters and requirements for developers. Now the City of Dana Point has also become a leader in implementing progressive water quality programs that address urban runoff issues.

Source control programs, while essential to a successful urban runoff program, take time to achieve measurable improvements at the receiving waters. So despite Dana Point’s ongoing source control efforts, its Monarch and Salt Creek beaches continued to issue a high number of health warnings (beach postings) due to high levels of bacteria in the water. However, more than 1.8 million people visit these beaches annually, and this tourism is vital to the local economy. So the city set out to find a solution that would provide near-term improvements in water quality.

The city examined its options carefully. Diverting flows to a treatment plant and chlorination were deemed infeasible for a variety of reasons; however, two revolutionary methods of “disinfecting” urban runoff — ozone and ultraviolet light — showed potential to meet the project’s goals. A comprehensive evaluation of both methods that addressed feasibility, capital and long-term operating costs, reliability and performance proved ozone treatment to be the most viable, cost-effective option to meet the city’s goals.

Ozonation Offers an Innovative Solution

The Salt Creek Ozone Treatment Plant is an advanced stormwater treatment facility that uses a combination of filtration and ozonation to reduce bacteria levels during dry-weather flows. The 1,700-square-foot facility can treat up to 1,000 gallons per minute of urban runoff. The Salt Creek Treatment Plant is the only facility in California that utilizes ozonation as the primary method of treatment for urban runoff — an innovative application of this technology that disinfects stormwater by infusing ozone. The overall treatment process also reduces trash and debris, sediment and associated pollutants.

The city contracts with South Coast Water District (SCWD) to operate and maintain the facility. SCWD’s expertise with traditional water and sewer facilities has contributed significantly to the facility’s success, and SCWD continues to adjust operational protocols to optimize the system.

Involving the Community

Engaging the community early in the planning process, a priority for Dana Point , was central to the project’s success because the treatment plant is located in a politically and environmentally sensitive area within Monarch Beach Golf Course and adjacent to affluent residential areas. To garner support for the project, the city proactively initiated an extensive campaign to involve the community, regulatory agency and other stakeholders. The city held several outreach meetings to allow stakeholders to voice their key concerns regarding facility location, aesthetics, visual obtrusiveness, noise and construction-related issues. Dana Point ultimately developed a facility that was not only functional and effective, but also aesthetically pleasing with a Spanish-style building that blends well with the sur rounding architecture. The facility, which is partially hidden within the golf course, also meets all noise and air regulations.

Financing and Building the Plant

To help fund the $6.7 million project, the State Water Resources Control Board awarded $4 million to the city for the project. Named Showcase Project of the Year, the Dana Point facility received the single largest grant awarded in California’s Clean Beaches Initiative. MiOcean Foundation, a local private organization that helps support and implement programs that protect California’s beaches and coastal waters, took an interest in the project and contributed $150,000. The city funded the balance.

Measures of Success

Strategic construction phasing was instru mental in successfully completing this project, which faced significant chal lenges, including a heavy rain season and building in an environmentally sensitive area with limited access. Using trenchless technology (pipe jacking) allowed the golf course to remain open, and enhanced best management practices eliminated construction stormwater concerns. Extensive community input continued throughout the project’s duration.

The Salt Creek Ozone Treatment Plant is entering its third season of operation, and the city has achieved significant success in improving water quality at the beaches. Monarch Beach water quality improved from a D grade prior to the project to an A in the most recent Heal the Bay 2008 Beach Report Card. The beach has not been posted with a health warning since 2006. South Coast Water District continues to operate the facility under contract with Dana Point. The city and South Coast Water District are exploring the feasibility of using the treated water for landscape irrigation.

The most significant achievement, however, is demonstrated by the beach data, which conclude that the Salt Creek Beaches meet the state’s de-listing criteria. This means that these beaches can be removed from the state’s 303(d) List of Impaired Water bodies for bacteria limits at sites used for recreation.

The treatment plant’s success has positively benefited tourism and the city’s economy. In addition, positive citizen feedback points to the facility’s success, including comments received from local lifeguards and surfers who have an intimate and long-term knowledge of the beach water conditions.

Another beneficial outcome of this project is technology transfer. Several technology and trade publications have featured this award-winning project, and experts have presented the project at a number of water-related conferences. The city has used the facility as a method of outreach and education for a variety of audiences beyond industry professionals, including students, residents, and colleagues in various disciplines.

The process of developing and operating the facility has helped city employees to inform the public about the local causes and effects of urban runoff. And the facility is a successful model for aggressive urban runoff management, offering another solution for cities grappling with similar issues.

Contact: Lisa Zawaski, senior water quality engineer, Department of Public Works & Engineering Services, City of Dana Point; phone: (949) 248-3584; e-mail: Lzawaski@danapoint.org.

This article appears in the August 2008 issue of Western City
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