“BiodiverCity” in San Francisco

I want to share what I learned during an afternoon at an event at the Exploratorium during the Global Climate Action Summit in California. The focus was the amazing array of biodiversity activities taking place all across San Francisco.

During the BiodiverCity Summit (get it?),  we heard from about from about twenty nonprofit and government agency presenters. They were physicians, scientists, educators, and researchers. Their stories were marvelous examples of creating opportunity for urban biodiversity with multiple benefits across the community.

Here are four (with links to valuable reports and resource sites) that illustrate policy alignment to encourage biodiversity, research that plans for it, and two implementation approaches that facilitate it — all in the face of a changing climate.


Peter Barstow of the city’s Department of the Environment described how San Francisco agencies collaborate to “operationalize biodiversity.” It took several years of planning for sixteen agencies to develop a resolution to propose to the Board of Supervisors for the City and County of San Francisco. The effort was worth it: the biodiversity plan for San Francisco was approved unanimously by the eleven supervisors. The vote made biodiversity equal in importance to other complex issues such as transportation and homelessness. The resolution provides a vision, sets goals, and identifies priority practices. It highlights the benefits of biodiversity to human health and well-being, and emphasizes the interconnectedness of solutions in addressing biodiversity and climate change.

It is a marvelous example of a powerful way forward for any area with a mix of entities with shared interests but without a clear working mechanism.  Their vision? All San Franciscans connect to nature daily and are inspired to participate in some form of ecological stewardship of the City’s natural heritage. San Francisco’s biodiverse, climate resilient, and verdant ecosystems are integrated throughout its natural and built environments.


Dan Gluesenkamp, Executive Director of the California Native Plant Society, introduced us to the biodiversity and distinctive climates in San Francisco. He named the three greatest threats to biodiversity, in reverse order: 3) greenhouse gases (global warming), 2) biological invasions – pests and diseases, and 1) bulldozers; “global paving” he called it.  The very recent publication of the California Biodiversity Initiative, a roadmap for protecting the State’s natural heritage, completed at the governor’s request, provides a comprehensive approach to current and planned biodiversity activities in the state. Specifically, the governor wanted to make the link between climate change and biodiversity, and set an example for the world. The report is divided into types of activities: understanding, managing and protecting. Among the activities to be begun, updated or completed:

  • Map every species in California all over CA to know what to save
  • Identify important/exceptional plant areas and make priority protection sites
  • Map the vegetation of California, first creating standards and training the public to collect data. So far they have mapped 50% of the state
  • Support the California Native Plant Society’s inventory, documenting that no plants have gone extinct since they created the inventory
  • Create the California Seed Bank as an insurance policy against catastrophe
  • Protect land: half of California is protected despite it being one of the most expensive markets in the world

Gluesenkamp concluded by emphasizing that this work ends extinction in California. He is serious. The state has lost populations but no species since biodiversity mapping and understanding began. Success starts with data and is ensured by a commitment to keeping extinction stopped.


Erica Spotswood of the Estuary Institute talked about “Re-Oaking” Silicon Valley, the plan to re-establish native oaks displaced over decades by the agricultural and, later,  urban expansion in the valley. She explained that since cities have not been developed with natural processes in mind, they will not easily weather coming changes, but native biodiversity can help them become more resilient.  She reminded us that “nature-based solutions provide services in a multi-benefit way, whereas engineering tends to give us a single solution” and that native biodiversity is already adapted for resilience, making it the smartest approach to resilience planning. To cope better with a changing climate, our built communities require heat island mitigation, carbon capture, flood risk mitigation, water conservation, and biophilia (access to nature for health but also to motivate stewardship). Re-Oaking addresses all those in some fashion.

The report describes how “re-integrating components of oak woodlands into developed landscapes — ‘re-oaking’ — can provide an array of valuable functions for both wildlife and people.” Native species tend to remove pollution, sequester carbon, and hold water better than non-natives and are more drought-tolerant. They create shade and wildlife habitats, too while supporting food webs that foster biodiversity. The research and recommendations in this report are excellent, and the format is perfect guide for other communities re-examining how to improve design for a healthier urban future.


Polly Perkins of the San Francisco Utilities Commission described the city’s Waste Water Enterprise, an approach that seemed to me to be the most enlightened, consumer-aware, fine-design approach to waste and stormwater systems and infrastructure management you are ever likely to meet.  Her examples of how to slow down, clean and route stormwater so that it does not overwhelm the combined waste and stormwater sewer system was impressive.

The utility has the advantage of a 2010 Stormwater Management Ordinance (and 2016 update) requiring green infrastructure installation and lifetime maintenance in large developments. For city-owned properties the utilities’ Sewer System Improvement Program requires green infrastructure in the streets from “green bulb outs” (see link), and permeable paving, rain gardens and bioswales. The work proscribes planning for repair as utilities age out, and provides for biodiversity and nature in the city alongside waste water management.  Check out the Waste Water Enterprise website for great examples.


These four examples demonstrate complex work on behalf of biodiversity and a healthy, climate-ready city. There were many more success stories shared that day. Like every summit meeting I attended, the host even had too may examples to fit the time allotted. That is a good sign – our situation is dire and yet the solutions are coming fast and furious.

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