Nature-Based Climate Adaptation Opportunities

To help planners and citizens wrap their head around what to do next in terms of “nature-based” solutions (rather than seawalls) to sea level rise, scientists and planners came up with 30 places to focus around the Bay’s 400-mile shoreline.

cover of adaptation atlas

In this Adaptation Atlas, scientists and planners identify 30 distinct operational landscape units (or OLUs) that share common physical characteristics. It is in these places, say the experts, we should invest in natural resilience because the units make sense in terms nature’s boundaries, rather the jurisdictional boundaries crisscrossing them with county lines and zoning limits.


The atlas uses Operational Landscape Units (OLUs) as a practical way to manage the physical and jurisdictional complexity of the shore, where there is no one-size-fits-all solution to rising sea levels.

A key purpose of OLUs is identify where nature-based approaches (such as beaches, marshes or subtidal reefs) will work best and create multiple benefits.  The atlas explains its science-based framework, describes more than 25 possible adaptation measures suitable to be deployed around the Bay, and provides opportunity maps for 30 specific OLUs in places ranging from San Rafael to Pinole to Colma and the Santa Clara Valley.  The atlas also discusses some nitty gritty policy, regulatory and financial adaptation approaches.

30 Sites for Nature-Based Adaptation

Given the complex and varied nature of the Bay shore, a science-based framework is essential to identify effective adaptation strategies that are appropriate for their particular settings and take advantage of natural processes.

Mowry Slough OLU Near Newark

In this OLU, for example, baylands that were once part of Alameda Creek’s alluvial fan are now used for salt production or managed wetlands. They provide a rare buffer between the Bay and developed communities, where an ecotone levee could be built to bolster climate resilience and provide high tide or high water refugia for local wildlife. At the southeastern end of this OLU there are unique opportunities to protect and prepare open space for marsh migration inland as the Bay rises. In the upper watershed, more green infrastructure could help prevent flooding in developed areas around the creek.

San Rafael OLU in Marin County

In this OLU, for example, space is limited by the setting in a small valley surrounded by headlands, and by all the urban development around the San Rafael Canal. Most of the historic marshes have been filled but there are a few opportunities for enhancement and ecotone levees (such as Tiscornia). Nearshore reefs or submerged aquatic plants and vegetation could provide habitat and slow waves and resulting erosion of the shore. Another nature-based opportunity would be to replace some rip rap with coarse beaches.