Those who live in communities where flooding is considered a high-risk factor have a one-in-four chance of flooding over the course of a 30-year mortgage. It isn’t just the high-risk areas that need to be concerned with rising waters and potential storm floods; nearly 25 percent of all flood claims are in low-to-moderate risk areas.
As many have been forced to rebuild after major hurricanes such as Irma, Sandy, and Andrew, both communities and homeowners are looking for ways to protect themselves from disastrous floods. Take a look at these eight out-of-the-box ways cities, communities, and homeowners are exploring to better manage flood risk.
Flood Risk Management: New Ways to Manage Old Problems
1. Sea Walls
A sea wall is an onshore structure designed to prevent water from flooding the coastline’s roads, promenades, houses, and other structures. Typically, sea walls are built parallel to the coastline and maintain a safe elevation from expected floodwaters during storms.
A sea wall proposed for New York City’s coastline involves man-made islands with retractable gates that attach to create a six-mile wall to guard against massive storm waters. Opponents say the solution is not enough – that a 20 to 30 foot wall wouldn’t solve the growing problems and could trap runoff and pollution within the wall. With a $119 billion price tag, it’s certainly not an immediate solution.
While most sea walls are viewed as a community endeavor, coastal homeowners can look into building their own barrier on their property line.
2. Fortify Beaches
The US Geological Survey predicts that 31 to 67 percent of Southern California beaches will be completely eroded without proper intervention. Beaches are a natural barrier to coastal waters, giving leeway from the shoreline to streets, homes, and other structures. The diminishing shoreline makes it easier for waves to overtake communities.
Even without a sea wall, there are ways to fortify a beach to manage floods:
- Sand dunes: Rolling hills of sand that create elevated peaks with valleys where water can pool to protect structures inland of the dunes.
- Vegetation: Holds sand in place, keeping it from being pulled out into the ocean with waves or blown away by the wind.
- Sand fences: Forces windblown and drifting sand to accumulate in a desired location.
While major beach fortification is often a community endeavor, homeowners living on the coastline can plant vegetation or build a sand fence to help maintain the beach adjacent to their home.
3. Pier and Beam Foundations
Hoisting a home above anticipated floodwaters has been used for decades in places like Hawaii. Instead of using a standard concrete slab foundation, the pier and beam foundation model raises the house with a crawl space under it. Water can flow through the crawlspace rather than pool directly in the home.
In the aftermath of Hurricane Harvey, Houston approved new building regulations requiring pier and beam foundations. The ruling came after a study found 80 percent of homes damaged during Harvey could have been prevented with pier and beam foundations.
This construction has benefits beyond flood prevention. All electrical and plumbing components under the home are accessible through the crawlspace. When a pipe leaks under traditional cement slab foundation, it’s difficult (and costly) to reach the pipe. But with pier and beam foundations, pipes are easier to access, which can help mitigate thousands of dollars in damage and repairs.
4. Floating Homes
US coastal communities are looking to European models of floating homes. In Finland, people are already lining up to buy amphibious homes – that is, homes produced at a manufacturing site, floated to the homeowner’s location, and anchored to the seabed with enough leeway to rise and fall with the ocean tides.
While it’s a creative solution to address both housing shortages and flooding issues, there are some drawbacks that impact its widespread viability. For starters, floating homes cost 8 to 16 percent more than traditional land-built homes. Plus, there’s the potential for more risk – emergency response may struggle to reach a home, and children may be at greater risk for drowning.
5. Breakaway Walls
The real ordeal with floods is getting water out fast enough to reduce damage. When water can’t drain from the home quickly, it continues to rise and damage secondary floors. A breakaway wall could solve this problem for multi-level homes.
The breakaway wall is a constructed wall that doesn’t support the structural needs of the home. As floodwaters hit the wall, it is designed to literally break away, preventing water from pooling on lower levels of the home. This protects the elevated levels of the home.
6. Flood Flaps
A flood flap is a vent structure installed in crawlspaces. It enables proper ventilation and potential flood drainage while completely sealing the crawlspace to reduce the chance of rodent infestation. As pressure builds from water entering the crawlspace, the flap opens to allow it to drain out.
When water drains from a crawlspace faster, it prevents the foundation from being saturated, which can cause substantial damage. It also helps keep crawlspace walls from breaking.
7. Residential Flood Barriers
If you live in a flood zone, you probably already know that sandbags are used as residential flood barriers to protect a home from incoming floodwaters. There are a few techniques beyond the sandbag method that create residential flood barriers:
- Door barriers. These prevent water from seeping in under the door or through the door jam.
- Portable dams. These expand with water absorption or inflate to build a barrier for more water to enter (often stackable to build a wall).
- Water walls. This is a soft or hard structure several feet high that surrounds a structure and diverts water.
If you live in a flood-risk area, you may want to consider some of these approaches to keep your home protected.
8. Private Flood Insurance
The benefit of private flood insurance is that it provides more coverage and is often more affordable than National Flood Insurance Program (NFIP) coverage.
For example, our flood insurance is available as an endorsement to your home insurance policy. That means you just add it on – no need to buy a separate policy, pay multiple premiums, and manage multiple deductibles. Plus, your coverage is effective immediately, and your home and personal belongings are covered to your homeowners limits.
That’s a stark contrast to the $250,000 limit from the NFIP for your dwelling and $100,000 limit on belongings.
Whatever route you choose, just remember: even the best mitigation efforts won’t prevent all damage. That’s why flood risk management isn’t complete without flood insurance.