“TIME TO BUILD” FLOOD RESILIENT INFRASTRUCTURE
Published by the Natural Resources Defense Fund
May 2017 flooding in Eureka Missouri. The second major flood to hit the town in less than 18 months. (U.S. Army National Guard photo by PFC Garrett Bradley)
The lower Midwest is still recovering after severe flooding swept through the region in early May. Cities and towns along the Meramec and Mississippi witnessed floods stages at historic or near historic levels. For places like Eureka, Missouri, this is the second time in less than 18 months that a major flood has occurred. Portions of I-55, a major thoroughfare for Missouri, have been inundated and shut down twice since Dec. 2015. While the chances of multiple major floods happening in a relative short time span is a possibility, climate change is loading the dice in favor of making such occurrences all too common. Bad news for infrastructure, like bridges, hospitals, and water treatment facilities, and the people who depend on it, in flood-prone regions.
As Infrastructure Week takes over Washington, D.C., one issue that must be at the forefront of discussion, is not only the pressing need to repair the nation’s failing infrastructure, but also the need to prepare it and future infrastructure projects for the coming impacts of climate change, like sea level rise and more extreme flooding. Accounting for these climate impacts in future infrastructure investment will better protect people and property, and save taxpayer dollars in the form of avoided disaster costs.
Fortunately, the Obama Administration took steps to prepare federally-funded infrastructure projects for a future of bigger and badder floods by issuing Executive Order 13690, which updated federal flood protection standards. The executive order directed federal agencies funding infrastructure projects in flood-prone areas to require the projects be designed with an additional margin of safety. Several federal agencies have moved forward with implementing the executive order, but more needs to be done to ensure that infrastructure built with taxpayer money lasts as long as intended in the face of a changing climate.
FUTURE OF EXTREME WEATHER
Climate change is exacerbating our nation’s susceptibility to disastrous flood events. As climate change raises sea levels and alters precipitation patterns, coastal areas and riverine communities will become increasingly susceptible to flooding. According to the National Climate Assessment, the heaviest rainfalls are becoming heavier and more frequent, paralleled by an increase in floods where the largest increases in heavy rain amounts have occurred.
Most significant are the increasing trend for floods in the Midwest and Northeast and the decreasing trend in the Southwest. (National Climate Assessment)
Sea levels are also projected to rise exponentially over the course of the century. By 2100, global mean sea level may rise as high as 6.6 feet. Even two feet of sea level rise will have serious ramifications, endangering more than 5,790 square miles of coastline and more than $1 trillion of current property and structures.
Sea level rise and an increase in heavy rain events are projected to continue for the foreseeable future. These climatic changes will have significant impacts on the reliability and operability of the nation’s infrastructure, with potential corresponding disruptions to the US economy. However, these climate impacts can be reduced through smart planning and adaptive actions. Executive Order 13690 is the type of climate smart policy that needs to be pursued.
FEDERAL FLOOD PROTECTION STANDARD
The Standard provides a pivotal framework for reducing our nation’s exposure to flood risk. Under the Standard, Federal agencies must use more protective design standards when making decisions about what and where to build, or in deciding which projects can receive federal funding. The Standard established flexible options for federal agencies to account for future flood risk when funding construction projects. One of the most important is the Climate-Informed Science Approach. Under this approach, federal agencies must use the best available climate science data to determine future flood conditions over the lifetime of the proposed structure, and elevate or flood-proof it above that future flood level.
The executive order also requires federal agencies, where practicable, to employ nature based approaches, like retaining wetlands to minimize flood risk. Not only does this approach preserve natural habitat, but natural infrastructure often can be more effective at mitigating risk than traditional gray infrastructure approaches because it is more capable of accommodating the unpredictability of weather events.
AGENCY IMPLEMENTATION
At present, federal agencies are moving to incorporate the federal flood protection standard into their regulations and operating procedures. FEMA, HUD, and EPA all have released draft rules outlining their approach for implementing the flood protection standard. For example, FEMA has proposed all critical infrastructure facilities for which it provides funding to be built or rebuilt after a major disaster account for future flood conditions, including sea level rise.
However, this is just the start. All federal agencies need to be moving forward with implementation of the executive order. And FEMA, HUD, and EPA need to finalize their proposed rules so that infrastructure projects built today include an additional margin of safety to account for the flooding of tomorrow.
INFRASTRUCTURE INVESMENT MUST ACCOUNT FOR FUTURE FLOODING
The flexibility of the federal flood protection standard for managing future flood risk allows infrastructure to account for the uncertainty of the future conditions. Traditionally, infrastructure was developed in a relatively stable climate. While we can’t be 100 percent certain what the climate will look like by the end of the century, we can be certain it will not be like the past. This calls for a new approach to how we design and build infrastructure projects. New projects should be built to accommodate for scenarios like more extreme flooding. You do not buy homeowners insurance because you are 100% certain your house will burn down, you buy it because of the possibility for such an event to occur. Well, a future of extreme flooding and sea level rise is a possibility. Building infrastructure to account for this possibility, such as the federal flood protection standard mandates, is an insurance policy for this future.
Read the full article at: https://www.nrdc.org/experts/joel-scata/time-build-flood-resilient-infrastructure
