Urban canyons or urban beaches: What's the choice?
A white paper by Elaine R. Brooks, MS, MSW
he Natural Resources and Culture Committee of the City of San Diego is going to consider the recommendations of the City Manager and the City Wide Canyon Sewer Maintenance Task Force regarding the urban canyon system, and the need for city crews to access them to monitor and repair the old sewage pipes in the bottoms of the canyons. It is widely acknowledged that sewage spills, sometimes in the millions of gallons, create public health problems for residents in neighboring areas and also result in large amounts of sewage-laden water ending up on our beaches. Human pathogens in the waters result in the closure of popular swimming and surfing areas a clear problem for our tourist economy.
Dig the canyons
Engineers who maintain our sewer and water systems see the problem of access as no more complicated than building an access road into each canyon, covering it with asphalt and putting up a gate. It is a simple engineering problem to them, easily solved with a bulldozer.
It is the same point of view that accepts the city as a place dominated by the needs of human activity: the only requirement is to maintain the urban infrastructure to safely support high population densities. Arguments about conserving or preserving native topography and biology mostly have been promoted out to the leading edge of urban sprawl, which continues to cover undeveloped raw land at the edge of the city. There, the squabble is noisy and visible. Developers with their bulldozers and the acknowledged need to create housing for a growing region have conducted ongoing battles with environmentalists. It's a morality play, not unlike old movies about western range wars that have become a cliche.
Wild by accident
Unfortunately, the urban canyons are an afterthought in popular thinking about protecting the environment. The urban canyon system is a kind of leftover in the city. It remains as it does today primarily because it was difficult and expensive to develop housing on the steep slopes in the early history of the city. So, these areas were bypassed as the city built out during the first part of the 20th century. The canyons were also a partial solution to the region's growing needs for a sewage system, as well as for management of the watersheds to prevent flooding. The canyons allow gravity-flow to the ocean, offsetting the expense of pumping sewage to treatment plants, and building flood control channels to control damage from rainfall runnoff.
The primary historical consideration given to open space within the city was entirely an urban cultural perspective. The city's showpiece, Balboa Park, and other similar but smaller spaces, were carefully designed for human activities and accented with vegetation from all over the world. There was and is a rich business in private landscaping, with individual gardens in private residences greatly enhanced by a reliable water supply coming from the state's water projects and nearly perfect mild climate conditions for importing and growing exotic plants from all over the world.
The idea of preserving wild landscape in the heart of the city is a new consideration. People saved wild things. The fabled horticulturist Kate Sessions created museum-quality living exhibits of odd and exotic native plants in demonstration gardens. But these natural objects were offered as a living sculpture, removed from their natural contexts, and exhibited much like a collection of postage stamps the places they came from rarely were valued.
It wasn't until the 1960s that urban planners and others began to recognize that the steep slopes in the city, whether canyons or mountains, were rapidly becoming the only places left containing some native vegetation and remnants of the original ecosystems. When Clairemont was built after WWII, the canyon system became obvious once again as the tops of the mountains were leveled and houses built, covering them to the canyon rims. As it spread out into the county, the city surrounded the natural canyons, one by one. The Hillside Ordinance was passed to protect the city's steep slopes. Since then, except for minor encroachment by creative developers, they have remained largely natural, given the enormous development pressures.
Wild by design
The 1990s habitat conservation program originated in the wake of a federal lawsuit concerning the treatment of sewage by the City of San Diego. Brought into court in the early 1990s, the lawsuit drew new attention to what remained of the urban canyons. The federal action asked the courts to look at the potential land damage associated with building a $12-billion dollar sewage system to protect the ocean, an enhancement being planned by consultants the city hired to help them respond to the lawsuit. Out of this legal requirement, the Multiple Species Conservation Program (MSCP) emerged. For a number of years, a wide variety of organizations in the region came together to try to answer the question of which lands should be set aside and never developed.
As an afterthought, really, a number of the canyons were included in the city's habitat conservation planning in the 1990s but only as opportunities to preserve open space, with no real commitment to do so which is really the status of the land identified during the MSCP planning. During that time, residents living around some of these canyons began to form groups to help conserve the canyons in their neighborhoods. So there are now Friends of Switzer Canyon, for instance. In once case, Florida Canyon in Balboa Park, the city took special steps after local activists took up the cause in the 1970s to set aside Florida Canyon as an official nature reserve. This canyon is now widely used by local educational institutions to introduce students to natural ecosystems.
There are nearly 40 such canyons within the city, ranging in size from a tiny one- acre site near 32nd street, to Florida Canyon's nearly 250 acres (the reserve is a much smaller part of this). Some of these canyons, such as Laurel Canyon, have been entirely surrounded by the city for nearly 100 years. Others have been surrounded only more recently, such as Rice and Sundown canyons. In these neighborhoods, generations of children born and raised in San Diego and have played in the canyons. Today, these canyon form an informal destination for joggers, bicyclists, walkers, people walking their dogs, or folks just out for an evening's stroll.
Canyons are really just neglected spaces in the city, as far as their management is concerned. They have informal recognition as a natural asset. Yet they have never been managed as official open space, except for fire control and sewage and flood control purposes.
Some of the canyons those that were isolated many years ago are nearly entirely vegetated with a whole suite of naturalized, exotic invasive species that dominate the urban environment, such as eucalyptus, palms, pepper trees, castor beans and mustard. If they were to ever represent the native ecosystems, they would require major restoration, something that is still more an idea and an art than anything we know how to do. Many are invaded by the creeping seas of ice plant that protect houses on the rims above from the natural wildfires. Others, such as Florida Canyon, still contain patches and fragments of the native coastal sage and chaparral communities, as well as clusters of native oaks.
But canyons serve important needs that are perhaps less exciting or obvious than that offered by theme parks or by the commercial possibilities of coastal development. They provide, to the countless thousands of people who live in and around them, a respite from the asphalt, stucco and concrete in a life dominated by automobiles, traffic, and by a city that is now nearly entirely engineered for cars. When they were children, they played in the canyons. Now, the canyons fulfill unheralded roles in refreshing the lives of thousands of people who jog through them, or who walk their dogs, or who simply stop for a glimpse from the end of a street.
Most residents of the city are also unaware that many research ecologists have used the canyon system as a natural laboratory to study the ecological theories related to habitat fragmentation and the preservation of native species that remain on these sites. Dr. Michael Soule, the renowned ecologist and widely recognized father of modern conservation biology, studied the San Diego urban canyon system and its native bird populations in the 1980s. A recent graduate student of Dr. Soule's at UC Santa Cruz did field work on native mammal populations in San Diego's urban canyons.
Dr. Ted Case from UCSD and his students, looking at insect and mammal populations, have followed in the footsteps Dr. Soule. Dr. Case and his students recently completed looking at the invasion of the Argentine ant populations into Southern California, using these canyons as some of their study sites. The research literature in terrestrial ecology contains many papers published by these scientists using the natural laboratory of San Diego's urban canyons. The diverse sizes of the canyons, the variation in ages determined by when they were isolated by development, their wide distribution over the landscape and their numbers represent a natural laboratory for looking at the effects of habitat fragmentation on populations. Research ecologists worldwide are aware that many of these important studies were carried out in San Diego's urban canyons.
Decisions made by the City Council about the engineering solutions to sewage spills may determine the ultimate fate of the urban canyons in the city. Will the urban canyon system only be seen as an engineering project to protect the recreational opportunities of beach-goers, millions of tourists who come to San Diego yearly, and the businesses that serve them? Will these canyons one day be opened up for development for condominium projects as a result of further degradation from these engineering projects? Or, perhaps, will the less tangible benefits of a wild and vanishing ecosystem, accessible and free in most neighorhoods in the city, be recognized? Will they become an important resource for area schools, an important accessible destination for walks and for picnics or children to play?
We are an urban population whose children's view of nature today exists mostly in two-dimensional images found on computer screens or nature documentaries. We are an urban population whose intimate experiences with wild nature are now relegated to vacations a yearly trip to a national park, or a packaged tour to Patagonia or Peru. The rest of the year, we live in our houses, in our automobiles on the freeways and roads of the city, seeing nature only in the bathroom calendar.
San Diego has the attraction of a mild Mediterranean climate with startling topography, and exciting tourist destinations with nature themes, such as Balboa Park, the Wild Animal Park, Torrey Pines State Park, the Birch Aquarium, the Zoo, and the Ocean Beach fishing pier. We now have a unique opportunity to develop a powerful new vision of our city: one that understands that providing natural open spaces the design of wild nature back into the city could be done as thoughtfully and completely as we provide roads and utilities. This would provide a powerful new dimension in the way we live and in the aesthetics of our city.
We don't have to put gates around nature and charge admission and pave over the rest of it. We can design it into our lives carefully, rationally and ecologically as we think about how to redevelop downtown, or how to design a network of bicycle paths, or create the roads that connect us.
Years ago, famous landscape architect Ian McHarg laid out a basic plea to planners: design nature back into the places we live; understand the basic rhythms and components of the natural ecosystems that exist in a place; rather than obliterating them, incorporate them into the design of human settlements. We are a long way from that in San Diego. But it could become just as important an engineering solution to our quality of life as are the engineering solutions to our to our sewer and water needs.
The urban canyons should be preserved as a system, managed as part of the open space in the city. They should be available to our schools for teaching children about a living nature, not one that only exists in textbooks and in television documentaries. We should be as protective of the urban canyons as we are of our beaches. We are a coastal city, and our natural heritage includes both the water and the land: our responsibilities lie in both places. We need to see both of them, not as mutually exclusive choices, but as essential parts of our urban lives.
If we do, nature as an element of domestic life can be a powerful amenity, not only for tourists who are teased by the photographs of San Diego from their armchairs in Des Moines or Dallas, but in our everyday lives as well if only we catch glimpses of it on the way to work in the morning, or see it for a moment as we look out a window, or stroll through it with a friend in the evening. We have an opportunity to recognize the importance of these urban canyons as intimate, living nature, as a real possibility in our everyday lives, to revolutionize the way we understand life in cities, which is increasingly the only place most of us will ever be. We can leave a powerful legacy by saving the urban canyon system as the true nature of this place, which will include both the ocean and the native landscape.
We have a choice. We can make decisions about our sewage system in such a way that the land is irrelevant, simply part of the construction material, in the name of expediency. Or, we can make a decision to have it all. It may cost more to do the engineering so that we can protect our beaches and also preserve the canyons. But if we don't do it that way, the opportunity will never reappear. If we send in the bulldozers and carve out the roads, once the roads are there, the condominiums are sure to follow.
Elaine Brooks, MS, MSW, is an Adjunct Professor of Biology at San Diego City College. Formerly, she was a plankton biologist at Scripps Institute of Oceanography, and was also very involved with Scripps scientists on the secondary sewage treatment issue in San Diego from 1988 to 1992. Ms Brooks developed one of the first college courses in urban ecology in the country, which was taught for the first time last year. Email: 74472.2677compuserve.com