Flooding on the Dock of the Bay

Flooding on the Dock of the Bay

Astrid Caldas
Union of Concerned Scientists
Time Slot: 
Concurrent Sessions 2
Session Type: 

How can historic waterfront districts adapt to rising seas? While these irreplaceable resources safeguard stories of our nation’s past and are often valued by locals and visitors alike, at the water’s edge they are first in line for storms and waves. With piers, docks, and bulkheads constantly exposed to saline conditions, and aging seawalls not designed to withstand accelerating climate change impacts, these sites are particularly vulnerable. Furthermore, integrity considerations add to resiliency challenges, with rigid design standards that limit elevation and other adaptation strategies for historic resources.

This session will showcase efforts underway in three historic bayside communities. Annapolis, Maryland recently completed the nation’s first Cultural Resource Local Hazard Mitigation Plan under the partnership-based Weather it Together program to identify adaptation measures for the Annapolis National Historic Landmark District abuting Cheaspeake Bay. Financing options are being explored to retrofit San Francisco’s Embarcadero, threatened by both earthquakes and sea level rise, including an infrastructure financing district and community facilities districts. Miami Beach, lying at ground zero of the nation’s sea level rise challenges is developing design guidelines to adapt their vulnerable historic districts.

With few existing precedents of historic resource flood hazard mitigation, this session will overview tools to minimize catastrophic losses to our nation’s coastal landmark communities.


Weather It Together: A Model for Community-Based Adaptation Planning
Lisa Craig, Michael Baker International
The San Francisco Seawall: Strengthening Our Past, Adapting to Our Present and Envisioning Our Future
Lindy Lowe, Port of San Francisco
Miami Beach Rising Above – Strategies for the Long Term Stability of the City’s Historic Districts
Thomas Mooney, Miami Beach Planning Department
The Tide is Getting Higher But We're Getting Ready
Astrid Caldas, Union of Concerned Scientists
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With sea level rise, high tides are capable of altering the landscape and changing the shape of usable space. Many cities along the coast will start seeing a lot more tidal flooding in the very near and eventually some areas are going to be permanently inundated.
But people aren’t going to wait until their homes, cultural and historical landmarks are flooded every day to respond to sea level rise. When does inundation due to high tides alone become so frequent and disruptive that business as usual becomes impossible? That is what we call chronic inundation, and is defined by inundation that occurs at least 26x/year over at least 10% of a community’s usable land. We sought to identify where and when that inundation will drive big changes in our communities. We wanted to help people and communities see this problem coming, get a sense of the time they have before things get out of hand.
Nationally, our report “Landmarks at Risk” highlighted sites in 15 states, from early American native sites in Alaska and Florida, through colonial settlements and civil war forts. Many of the historic sites we looked at were coastal. As an introduction to this session, I will give an overview of projected chronic inundation along the US coast, and highlight a few examples of historic locations at risk.