Case Study: Elevate Homes on a Beach

Location: Private residences - Wells, ME

Problem: Houses located on or close to the beach are vulnerable to floods as sea levels rise and storm surges become more frequent.

Solution: Because flood risks change over time, flood zones are mapped by the Federal
Emergency Management Agency (FEMA), and made available to the public as Flood Insurance Rate Maps (FIRMS). These maps are used to identify flood insurance premiums in areas associated with different flooding events. As of 2014, FEMA is in the process of revising, digitizing, and proposing these maps for public review. As a result of these revisions, flood zone designations for some properties may be proposed to change. To review the most current maps, visit your local municipal office and consult with your Code Enforcement Officer, or find them online at FEMA's map service center.

New houses being built in these zones, or renovations that cost more than 50% of the home’s value, must meet coastal construction standards that limit the risks and subsequent damages from flooding. Depending on the zone, some houses may be required to use a foundation that allows water to flow through it during floods, or to be elevated on piers to a height above the 100-year flood level.

When new owners purchased a house at the north end of Wells Beach facing the Webhannet River, they decided to tear it down and rebuild rather than renovate the older structure. The new structure is elevated on 30-foot piers that also extend an average of six feet below grade, allowing flood water and storm surge to flow under the house, rather than through it. As is typical, the piers will be covered by lattice; the openings must be a certain size to permit adequate water flow.

Estimated cost: up to $100,000 or more.

Another home at Wells Beach has a flow-through foundation with water-sensitive panels or vents that break away under pressure, allowing water to escape. The base of the foundation is a concrete slab at grade. Sump pumps discharge any excess water after flooding. These openings cost $300-$500 per panel, and the total number of panels required depends on the overall square footage of the structure. They can work in new construction, and also could potentially be added to retrofit an existing structure, although property owners will need to consult with an engineer in either case.

Always consult with the local Code Enforcement Officer before beginning any work, and to learn about these zones and your building options.

“Flood zones are going to change, and more properties are going to be in hazard zones,” — David Johnson, Code Enforcement Officer for the Town of Wells.

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