Regulating Construction Norms:Limits and Capabilities in Addressing Floods

In an effort to mitigate the impact of floods in flood-prone areas, several initiatives are being implemented. These measures encompass preventive flood protection strategies such as upgrading infrastructure to resist water damage, reinforcing and sealing buildings, installing flood barriers, and improving drainage systems. The costs associated with these efforts can vary significantly, taking into account material, labor, and long-term maintenance expenses. Often, public funding and insurance incentives support these projects.

The building codes implemented in these areas meet or exceed the minimum construction standards established under the National Flood Insurance Program (NFIP). In regions like the Hill Country along the Guadeloupe River, the Asheville region in North Carolina, and the Appalachian areas of eastern Kentucky, where mountain valleys and river channels make fast-moving waters and flash flooding common, these measures are crucial.

In the built environment, shallow urban flooding can occur when storm drains get overloaded. To address this issue, homeowners have the option to build their homes to above-code standards for an additional cost. It is worth noting that buildings constructed according to current codes withstand flooding far better than older structures.

The Flood Insurance Rate Maps (FIRMs) developed by FEMA identify specific flood hazard areas around water based on the probability of flooding. These mapped flood hazard areas include the traditional 1% annual chance (100-year) floodplains, known as special flood hazard areas, floodways, and on some maps, the 0.2% annual chance (500-year) floodplain.

Construction in floodways is heavily restricted. A number of home building strategies and techniques can be used to prevent flooding, such as elevating buildings above the flood level. The cost of 1 foot of elevation above grade for a typical slab-on-grade home ranges from $4,800 to $12,200 depending on the method used and climate zone.

Recent tragedies, such as the flash floods in Central Texas in July, underscore the importance of these measures. In response, the National Green Building Standard (NGBS) is set to be published with an updated standard that includes topics such as resiliency from water events.

Moreover, Home Innovation Research Labs and NAHB recently developed a series of guidelines published by HUD for designing homes for natural hazards, one of which is for water risks. Enhanced building codes required in flood zones, as specified by the International Residential Code (IRC) Section R306 and International Building Codes (IBC) Section 1612, further emphasize the importance of flood-resistant construction.

However, the housing affordability crisis in America is a significant concern when considering the costs associated with flood prevention measures. Efforts are underway to make these measures more affordable, ensuring that everyone can live safely in flood-prone areas.

Floodplains come in various shapes and sizes, including deep river valleys, broad floodplains adjacent to lakes, and coastal areas subject to ocean waves and storm surge. Areas of the Great Plains along the Missouri and Mississippi rivers often have broad floodplains where floodwaters can be shallower and slower moving.

In conclusion, while the costs associated with flood prevention measures can be substantial, the benefits in terms of safety and property protection make these initiatives worthwhile. As we continue to develop and implement these measures, it is essential to consider the affordability aspect to ensure that everyone can live safely in flood-prone areas.