Competition Background

Over the past few years, the San Francisco Bay Conservation and Development Commission (BCDC) has become increasingly concerned that continued sea level rise from global warming will have profound impacts in the San Francisco Bay region.

The historic rate of sea level rise has been measured in San Francisco Bay for over 140 years. Between 1900 and 2000, the level of the Bay increased by seven inches. While some may view this as negligible, sea level rise has been predicted to accelerate significantly. Although we do not know how high the water will get, or how soon it will rise, current estimates are that sea level rise from warming oceans may be 1.4 meters (about four and a half feet) over the next 100 years, and possibly higher depending upon the rate at which glaciers and other ice sheets on land melt.

BCDC has prepared illustrative maps showing that a one-meter rise in the level of San Francisco Bay could flood over 200 square miles around the Bay. An estimated $100 billion or more worth of public and private development could be threatened with inundation.

Impacts from sea level rise are most likely to occur in concert with other forces that already contribute to coastal flooding, such as storm surge. When these forces are superimposed on higher sea levels, the result will be short-term, extremely high water levels that can inflict damage to areas that were not previously at risk.

As a result, there is a need to inspire creative thinking on how to integrate existing and future built environments with predicted coastal processes. The Rising Tides competition was intended to provide coastal communities worldwide with a suite of design concepts and ideas that create resilient shoreline communities that address coastal hazards and preserve and enhance coastal resources.

In the San Francisco Bay Area, the notion of designing resiliency into new shoreline projects has been compared with the region’s successful response to seismic activity through the design of structures that can withstand earthquakes. Rather than retreat from the shoreline, resiliency can attack the problem of sea level rise by using the economic engine of private development to provide flood protection both for new projects and existing inland development in low-lying areas.

Designing resilient habitats is equally as important as designing resilient human settlements. Continued stewardship of these habitats may involve building resilient development projects that accommodate the dynamic natural processes needed to sustain Bay habitats and fish, wildlife and other aquatic organisms dependent on these resources. For example, development projects that accommodate wetlands could benefit from the associated flood protection. Similarly, managed ponds that provide bird habitat may serve other purposes, including storm water retention or wastewater treatment.

The greatest threat to the San Francisco Bay Area over the next century is that climate change will make the Bay larger and lead to flooded communities, inundated transportation facilities, and submerged wetlands. BCDC hosted the Rising Tides ideas competition to generate and share design responses to these challenges that can be applicable in San Francisco Bay and elsewhere around the world.