Sea Level Rise, Growing Flood Risks, and the Need for a Strong Federal Flood Risk Standard

By Rachel Cleetus, Senior Climate Economist, Union of Concerned Scientists

On January 30, 2015, President Obama issued an executive order to strengthen the Federal Flood Risk Management Standard (FFRMS) and create an extensive stakeholder process for implementing it. Tomorrow is the comment deadline for the implementation guidelines proposed by FEMA and UCS has weighed in with support for a strong FFRMS.

Science-based flood risk management standards

Under the new standard, when federal agencies build or rebuild in flood-prone areas, they must use more protective design standards to guard against flood risks. Agencies will have the flexibility to choose among three approaches:

  • Use the best-available climate science.
  • Build two feet above the 100-year (1 percent annual chance) flood elevation for standard projects and three feet above for critical buildings like hospitals and evacuation centers.
  • Build to the 500-year (0.2 percent annual chance) flood elevation.

(It’s important to note that these standards will not affect flood insurance rates under the National Flood Insurance Program and they do not regulate private development.)

We’ve voiced our overall support for these protective standards, and recommended that adhering to the best available climate science information, when possible, is the most effective way to ensure the standards remain protective as flood risks increase over time as a result of sea level rise and other factors. This is especially true for long-lived infrastructure.

It’s critical that the standard stay strong, and tied to science and common sense in decision making, as it is implemented by the relevant federal agencies.

Growing flood risks, largely because of sea level rise and increasing development

According to the 2014 Third National Climate Assessment, climate change and other factors may increase the risks of flooding in many U.S. regions. For example, the report says that “The risks from future floods are significant, given expanded development in coastal areas and floodplains, unabated urbanization, land-use changes, and human-induced climate change.”

Global sea level rose roughly eight inches from 1880 to 2009, with global warming as the main driver. Sea level rise is also accelerating, nearly doubling in recent years. The East and Gulf coasts of the U.S. are experiencing some of the highest and fastest rates of relative sea level rise globally, in part due to additional local factors like land subsidence, groundwater withdrawals, and changing ocean currents.

As UCS’ Encroaching Tides report pointed out, flooding during high tides is now common in many places on the East and Gulf coasts of the U.S., and is projected to worsen as sea level rises. In addition, rising seas are also contributing to worsening flood risks and damage from storm surge, and increasing coastal erosion. Simultaneously, growing development in the floodplain is increasing exposure to flood damages. Hurricane Sandy showed how devastating storm surge in a densely developed area can be. It is estimated that the storm caused $165 billion in damages and 159 deaths, damaged 650,000 homes and left 8.5 million customers without power.

Building resilient communities nationwide, spending taxpayer dollars wisely

A strong flood risk management standard can help communities in floodplains become more resilient. In fact, according to the Association of State Floodplain Managers, many communities have “freeboard” standards that meet or exceed the FFRMS. “Freeboard” is the height required, above base flood elevation, for the lowest level of a structure, and is used to provide a margin of safety to account for the many factors that contribute to flooding. At least 42 cities, towns and counties have already adopted a standard of 3 feet of freeboard, at least 190 have adopted a 2-foot freeboard standard and about 300 have adopted a freeboard standard consistent with the FFRMS. These include a number of communities in New Jersey, such as Avalon, Hoboken (in the V zone), Somers Point, and Monmouth Beach. Adopting strong, harmonized standards nationwide would boost protection across the floodplain.

We also recommended that special attention be paid to equity considerations in the implementation of the Executive Order. In particular, the implementation should not result in any undue burden on communities of color or low-income communities, and agencies should prioritize funding for building resilience in these communities that are often on the frontlines of climate impacts.

A robust process of stakeholder engagement

The strengthened FFRMS is informed by recommendations from the 2013 Hurricane Sandy Rebuilding Taskforce and the President’s State, Local, and Tribal Task Force on Climate Preparedness and Resilience, and an extensive interagency consultative process. It is now going through a robust stakeholder engagement and comment process. After this, an interagency group (the Mitigation Framework Leadership Group or MitFLG) will revise the draft Implementing Guidelines, and provide recommendations to the Water Resources Council (WRC). Once the WRC issues amended Guidelines, agencies can work on implementing the standard.

We commend the inclusive and rigorous stakeholder process, and look forward to an efficient way to get to the implementation phase when improved decision-making can begin. Communities are already facing growing flood risks and delay is costly.

Smart risk management and smart economics

It’s bad policy to build in ways that perpetuate our risk of flooding and to sink taxpayer dollars into risky rebuilding efforts. Federal funds should instead be spent on making coastal communities more resilient to sea level rise and coastal flooding. We need to manage our risks and our dollars smartly – and a strong FFRMS is a step in the right direction.

Originally posted here.