›› Imperial Beach Ocean Water Quality and Community Health

Imperial Beach, California is the most southwesterly city in the continental United States. It has 3.5 miles of beautiful southern California coastline, used for swimming, surfing, fishing, and beach recreation.

In July 2008, Imperial Beach Health Center received a grant from the Networking for Community Health program of the Community Clinics Initiative, which is a joint project of the TIDES Foundation and the California Endowment. The program goals are to address community and environmental health issues and strengthen community partnerships. The three primary partners of this Networking for Community Health project are Imperial Beach Health Center, a community health center; WiLDCOAST, a grassroots environmental organization; and Dr. Rick Gersberg (Graduate School of Public Health at San Diego State University) a specialist in ocean water quality off Imperial Beach.

Forces Behind the Issue

For decades, sewage from the city of Tijuana, Mexico has flowed into the Tijuana River and across the international border into the Tijuana Estuary and then out into the ocean just south of city of Imperial Beach, CA.  Such cross-border pollution is a result of the lack of a proper sewage infrastructure in the city of Tijuana, Mexico, and its inability to keep up with rapid population growth and industrialization. During rain events particularly, such sewage contamination moves north along the coast. As a result the beaches of Imperial Beach can be heavily impacted, so that water quality at these beaches is extremely poor after rains, or when the Tijuana River is flowing. Such pollution of the Tijuana River not only affects people in Mexico, but also adversely impacts ocean water quality for those living in the United States (particularly in Imperial Beach), where many people have regular contact with the ocean either through recreational uses such as swimming and surfing, or by eating fish caught in the area.

A recent study by SDSU public health professor Rick Gersberg showed that within 72 hours after rainfall, coastal waters near the U.S.-Mexico border almost always harbor harmful viruses, in addition to the bacteria that are usually measured to detect health threats.  Gersberg et al. (2006) detected both hepatitis A virus (HAV) and a variety of enteroviruses that can cause human disease. At the Tijuana River mouth, HAV was detected 86 percent of the time, and enteroviruses were found in 100 percent of the samples, while at Imperial Beach (near the pier), HAV and enteroviruses were detected 79 and 93 percent of the time, respectively during rain events.

Aside from sewage, contamination by chemicals has also worsened in recent years with intensive industrial development associated with the maquiladora (in-bond manufacturing and assembly plants) program in Mexico. Unfortunately, an industrial pretreatment program similar to one implemented in the U.S. has not been initiated in Mexico. Moreover, in Mexico there is no program equivalent to the U.S. EPA’s National Pollutant Discharge Elimination System (NPDES) permitting program, so the threat of contamination of the nearshore coastal waters to Imperial Beach by toxic industrial chemicals is particularly pronounced. Indeed, although discharges from the Tijuana River account for only a small percentage of total gauged runoff into the Southern California coastal ocean, it contains the highest concentrations of the toxic metals - cadmium, copper, nickel, lead, zinc, and the toxic organic compound PCB,  among the eight largest creeks and rivers in Southern California (SCCWRP, 1992). Moreover, it remains the single greatest source of lead loading to the coastal ocean of the Southern California region.  The shoreline pollution is a multidimensional problem impacting the health, economy and well-being of Imperial Beach and adjacent coastal communities.
  

Project Activities

This project has:

1. Investigated the human health risks of exposure to contaminated ocean water at Imperial Beach from the Imperial Beach-Tijuana Slough area (where ocean users surf and swim in winter rainy periods when contamination from the Tijuana River is highest) to the north end of Imperial Beach. Wilcoast volunteers surveyed beach and pier users to determine ocean use and exposure patterns, and samples of fish caught at Imperial Beach Pier were analyzed for chemical contamination under Dr. Gersberg's direction.
2. Vaccinated Imperial Beach ocean users who were at risk for Hepatitis and treated Imperial Beach Health Center patients who suffered other problems as a result of exposure.

The project will continue to:

1. Educate the public, and especially ocean users and fishers, about the risks of contact with ocean water, and consuming fish caught at the Imperial Beach Pier, and about strategies for enjoying the ocean safely.
   

Project Partners

Imperial Beach Health Center is a Federally Qualified Community Health Center that has been serving Imperial Beach and surrounding areas of southwest San Diego County for 37 years. Federally qualified health centers are community-based and patient-driven organizations that serve populations with limited access to health care. Imperial Beach Health Center serves primarily low-income, uninsured or underinsured, and limited English proficient patients.

Imperial Beach Health Center (IBHC) is located in and serves a high need community. IBHC provides comprehensive primary health care services as well as supportive services (education, translation and transportation, etc.) that promote access to health care; provides services available to all with fees adjusted based on ability to pay; and meets other federal performance and accountability requirements regarding administrative, clinical, and financial operation.

Professor Rick Gersberg, Division of Occupational & Environmental Health of the Graduate School of Public Health at San Diego State University, has been studying the Tijuana River Estuary and sewage pollution since 1990. In 2002-2003 Dr. Gersberg was the principal investigator of a human health risk assessment for enteroviruses and Hepatitis A virus in runoff from the Tijuana River and in bathing waters of nearby Imperial Beach.

 Dr. Gersberg has extensive knowledge about human health risks in waters off Imperial Beach, and the resources and knowledge to develop research-based evidence. This research–based evidence will be used to inform the public and influence health policy about the ocean waters near Imperial Beach. If public health policy can be influenced to improve public health in Imperial Beach, the precedent may be used to promote positive policy changes for environmental health at other beach locations nearby.

WiLDCOAST is an Imperial Beach based non-profit organization addressing environmental health threats posed by Tijuana River pollution. With support from the California Endowment, Alliance Healthcare Foundation and The California Wellness Foundation, WiLDCOAST has made significant progress in documenting the health risks to area ocean users, carrying out environmental health education, and building the capacity of community leaders to advocate for clean water solutions.

WiLDCOAST has an active volunteer base in Imperial Beach, experience conducting media campaigns, has political strength, and an extensive and practical understanding of our local ocean water quality, ocean water users, and community dynamics surrounding ocean water policies.