Floodproofing

Diagram of 100 Year Flood Plain Line at Olmsted Center.

OVERVIEW
Floodproofing is any combination of structural and non-structural additions or adjustments to a building, which collectively reduce or eliminate damage from flooding.

Flood-resistant material is any building product capable of withstanding direct and prolonged contact with floodwaters, for at least 72 hours, without sustaining any damage requiring more than cosmetic repair.

The Base Flood Elevation (BFE) is the elevation to which floodwater is anticipated to rise during the base flood. The BFE describes the elevation requirement for the floodproofing of structures.

BENEFITS
+ Increases building safety and resiliency
+ Reduces risk of costly flood damage

CHALLENGES AND OPPORTUNITIES
+ Limited applicability for existing buildings

PROCESS
Wet floodproofing entails the modification of a building’s lower structure to allow floodwaters to enter and exit.

Dry floodproofing entails the use of waterproof coatings, impermeable membranes, and/or supplementary layers of masonry or concrete to seal the walls below the floodline.

CASE STUDIES
Olmsted Center – Phase I
BKSK Architects
Queens, NY
9,350 square feet

ADDITIONAL RESOURCES
Designing for Flood Risk [PDF]
NYC Department of City Planning

Post-Sandy Initiative
Spearheaded by the American Institute of Architects New York

Building Resilience Database: Wet Floodproofing
NYC Department of Design & Construction

Building Resilience Database: Dry Floodproofing
NYC Department of Design & Construction