In 1999 the City of Huntington Beach in effect canceled summer by posting signs warning that the beach was contaminated with fecal bacteria. Three years later, the problem continues, although postings are now less frequent. The major source of the bacteria remains elusive. Although those of us who have studied the problem can offer many ideas as to what the source—or sources—might be, no clear cause has been identified. Meanwhile, the city continues to weather the economic impact of fewer visitors.

The absence of a single cause, of a single villain polluter, is frustrating to experts, managers, and beachgoers alike. But the search for that cause has laid the foundation for a new understanding of coastal waters. We have acquired valuable information about the ways bacteria and viruses can be transported and how long they may pose a danger to human health. We have also identified critical knowledge gaps that must be filled if we are to deal effectively with the public health threat of beach water pollution.

That bacterial contamination is a widespread problem became clear—or at least official—in spring 1999, when state legislation (AB 411) went into effect requiring local authorities to test popular ocean swimming waters regularly and to post a warning if any of three indicator bacteria concentrations exceed prescribed levels. Excessive levels of these bacteria, which signal the presence of human and other fecal matter, are interpreted as indicating the presence of pathogens and the risk of getting ill.

The monitoring and posting that resulted from AB 411 drew attention to an alarming number of beaches where contamination was systemic, including Huntington Beach, Imperial Beach near the Mexican border, and beaches in enclosed bays, such as Mission Bay and Newport Bay, that are popular with families.

Although the incidence of illness associated with high levels of these fecal indicator bacteria is not well quantified, the mere idea of fecal wastes polluting our beaches was enough to spur public outcry and political action. The identification and elimination of sources of fecal pollution have become major priorities statewide. After all, California’s beaches receive more visitors than the beaches of all other states combined. In addition to the reality of pollution and illness, the intermittent presence of signs warning of bacterial hazards in the water creates a perception among beachgoers (and potential beachgoers) that the posted beaches are always polluted. A flurry of local and state actions, including the Governor’s Clean Beach Initiative, followed AB 411 and, during the past two years, resulted in many improvements. Numerous beaches were spared from contamination events as leaking sewers were repaired and rogue storm drain flows were diverted to treatment plants. At other beaches, however, the sources were not obvious, so managers and researchers started looking at populations of birds and seals, river outflows, and wastewater discharge from ocean outfalls as possible sources.

Alarming Responses

The impact of beach pollution on local economies and communities has led to a strong push to lower fecal indicator bacteria levels. With this comes the possibility that drastic measures are taken—measures that could significantly harm living coastal systems (and, in turn, humans) while providing an equivocal public health benefit. In many coastal cities, “nuisance” birds are being chased away from some beaches, but already the idea has been raised that we could improve coastal bacteria levels by chasing all birds away from the coastal waters where we want to swim, and from nearby wetlands. While the focus is on “nuisance” birds, there is no clear line between keeping these birds at bay and chasing away birds or seals that play key roles in coastal ecosystems. Further, the idea of disinfecting streams of bacteria is being implemented through an ultraviolet-treatment facility on Cottonwood Creek in Encinitas, San Diego County. While this process will render fecal bacteria harmless, thereby reducing contamination of beach waters, it undoubtedly kills other microbes and planktonic organisms as well; and more generally, it interrupts the ecological continuum of the ecosystem from stream to estuary to ocean. These approaches are in addition to the commonly accepted practice of removing water from creeks (diverting polluted flows to treatment plants) or of capturing urban runoff before it enters creeks. While very effective in lowering fecal bacteria levels in streams, estuaries, and along beaches, the water and other water-borne material is also removed from the downstream aquatic environments with little knowledge of the environmental impact.

Coastal environments are complex interwoven systems and, as history has repeatedly proven, drastic actions taken to remedy problems before they are fully understood often do more harm than good. As a society, we cannot make informed decisions about gains and losses, nor develop smart strategies, without improved knowledge of coastal oceanography, coastal and wetland ecology, microbial ecology, epidemiology, and detection technology.

AB 411 is an important step toward our acquisition of that knowledge. Now we need to move forward: We need to know much more precisely than current monitoring can tell us when and where swimming waters are polluted; where and how contaminants enter the ocean and by what routes they arrive at beaches where people swim and surf; how the presence of fecal bacteria actually relates to human health; what specific pathogens are found in polluted water; and how to reduce both the discharge of and people’s exposure to contaminants that endanger human health.

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It is sensible to recognize two kinds of coastal pollution: that which threatens the integrity and health of the coastal ocean ecosystem, and thus many ocean-based resources; and that which directly threatens human health. Nationwide, the single biggest threat to ecosystem health is nutrient pollution—the overfertilization of the coastal ocean due to human activities, leading to algal blooms and oxygen deficiencies. Other threats are due to discarded organic compounds, including pesticides and other poisons, detergents, and industrial chemicals. Thirty years ago, the Clean Water Act sharply reduced the flow of pollutants through wastewater systems and pipes, but that flow continues from “non-point” sources, via rivers, storm drains, and other routes. While the importance of non-point pollution for the ocean has been recognized for some time, and much work is under way in coastal watersheds to reduce this flow, only now are we beginning to seriously examine the destination of these pollutants in the coastal ocean itself.

Detective Work

This is where oceanography enters the stage and where we encounter major gaps in knowledge. One can think of pollution as being the story of the S and the 3 T’s: Source, Transport, Transformation, and Target—there are more conventional technical terms, but this is how I tell the story. S is the baddie and our ultimate game plan is to get rid of him. However, realism indicates that with population density and economic development being what they are, we will always have some pollution sources, be they intentional or accidental. In recognition of this, and in concert with our efforts to reduce pollution sources, we need to give attention to the 3 T’s. Where are pollutants being transported? How are they being transformed en route? Which targets are susceptible

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Attempts at cleanup must be based on solid knowledge: decisions have to be made regarding not only which problems are real, but also which problems can be fixed and how best to fix them. We do know that coastal waters are contaminated, and we know that there is a possibility of contracting illness from swimming and surfing in contaminated waters, but the detection of fecal bacteria and the causative link between concentration and illness needs to be better grasped before we adopt drastic strategies that may do more harm than good.

Further, the strategies need to be smart. They must protect nearshore ecosystems as well as public health. As we build our capacity to devise such strategies—through research in coastal oceanography, detection technology, coastal and microbial ecology, and epidemiology—our focus should remain on stopping pollution where it is generated, up in the watershed, along the shore, and in the water as well. It is still a safe bet that we can do the environment and ourselves no better service than to stop pollution where it begins, at its source.

John Largier, faculty member of Scripps Institution of Oceanography since 1988, conducts research in coastal oceanography, focusing on nearshore water movement and its importance to ecological issues.

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