Federal agencies address increasing flood risks with new rules

New floodplain rules implement the Federal Flood Risk Management Standard to address the risks of climate change.

The Federal Emergency Management Agency (FEMA) issued a new floodplain rule in July, requiring construction projects that receive agency funding to be elevated above current and anticipated future flood levels. The rule came as catastrophic flooding hit communities in Texas, Iowa and Vermont, in the latest round of extreme weather events that are posing increasing risks to people and property across the country while also driving up insurance costs.

With this new rule, FEMA will account for the impacts of climate change on increased flood risk and require enhanced resilience for FEMA-funded buildings and other construction projects in at-risk areas. FEMA joins the U.S. Department of Housing and Urban Development (HUD), which adopted a similar rule in April expanding its floodplain definition and increasing elevation requirements for HUD-assisted new housing.

These new flood rules are a critically important step to improve the preparedness of our nation's infrastructure in the face of growing climate risks and to use taxpayer dollars more prudently in building and rebuilding projects.

The Federal Flood Risk Management Standard

The FEMA and HUD rules both implement the Federal Flood Risk Management Standard (FFRMS). FFRMS is a flexible framework designed to address current and future flood risks and increase the resilience of federally funded infrastructure. Federal agencies are required to select one of three approaches to identify the FFRMS floodplain used for project siting, design and construction:

• Climate Informed Science Approach (CISA): The flood elevation and hazard area that result from using the best-available data and methods integrating current and future changes based on climate science.
• Freeboard Value Approach (FVA): The area that results from adding 2 feet to the base flood elevation (flood event with 1% annual probability) for noncritical facilities and adding 3 feet for critical facilities such as hospitals, power plants and water treatment facilities.
• 500-year floodplain: The area subject to flooding by a 500-year flood (an event with 0.2% annual probability).

FEMA and HUD have prioritized the use of CISA, where data is available and actionable, in their FFRMS implementation. Where data is not available, both agencies will generally defer to the higher result of the FVA or 500-year floodplain approach.

Affected federally funded projects

The HUD rule went into effect on May 23, with full compliance required by Jan. 1, 2025. The rule applies to all new or substantially repaired homes, including single-family and multifamily, that receive HUD funding. Homes receiving mortgage insurance from HUD's Federal Housing Administration will also be required to meet the new 2 foot elevation requirement above local flood levels.

FEMA's rule goes into effect on Sept. 9. The rule applies to any new construction, substantial improvement or repair of substantial damage under FEMA programs such as the Hazard Mitigation Assistance Grants program and recovery programs.

What other agencies can do

Under Executive Order 13690 from 2015, which was revoked in 2017 and then subsequently reinstated in 2021 by President Joe Biden, all federal agencies are required to implement FFRMS in their policies and procedures to manage flood risk. HUD and FEMA are the most recent agencies to do so, joining others such as the General Services Administration (GSA). The actions by HUD and FEMA are especially important, as these agencies have roles in providing funds for state, local and private sector construction and rebuilding.

Other agencies can follow suit to implement FFRMS and ensure all federally funded building projects account for flood risks. In fact, USGBC has championed federal legislation (the GREEN Building Jobs Act, introduced in the 116th and 117th Congresses), which would codify FFRMS for GSA to increase flood resilience across the federal buildings portfolio.

How LEED is addressing flood risk

USGBC recognizes the need to reduce the risk of damage from catastrophic natural events through improved building resilience, and the latest published draft of USGBC's rating system, LEED v5, would require all projects, both new construction and existing buildings, to complete a Climate Resilience Assessment that identifies current and anticipated future natural hazards, including flooding.

Further, LEED v5, which is undergoing revision following a public comment period, would require new construction projects to meet a prerequisite focused on flood avoidance and mitigation. The Resilient Site Design prerequisite would require projects' critical utilities to be designed to withstand flood events up to the 500-year floodplain level based on science-based projections. Additional resilience measures would be optional and rewarded through credits.

The second public draft of LEED v5 is expected in early fall 2024.

Learn more about FFRMS

Comments

Related articles