By Patricia Houser
For Nature’s Sake
Patricia Houser
Flooding is the most frequent and widespread natural hazard impacting Connecticut, according to the state Department of Energy and Environmental Protection. It’s also becoming more complicated today as patterns of rain and wind continue to shift with climate change. That’s all the more reason, say experts, to encourage more local residents to help community resilience by equipping themselves with some basic facts on flooding.
A first stop for residents beginning to explore the topic of flooding is to look up their home address, workplace or school in the online, searchable map at fema.gov created by the Federal Emergency Management Agency. A look at the FEMA maps for Orange and Milford show several districts within those places outlined in blue and labeled as high risk or prone to a one-in-100-year flood. That seemingly modest likelihood translates to a 26 percent chance of flood over a 30-year period, which is serious enough to make flood insurance a requirement in those areas.
At the same time, residents should know that areas outside of the high-risk zones on those maps are not necessarily risk free. FEMA’s website makes it clear that flooding can happen anywhere. By way of example, roughly 90 percent of damages from deadly rainstorms in southwestern Connecticut last August occurred in areas that were not designated as flood zones.
The National Oceanographic and Atmospheric Administration defines flooding, most simply, as an overflowing of water onto land that is normally dry. The three most common types of flooding are coastal flooding; fluvial flooding, which is associated with overflow of rivers and streams; and pluvial flooding, which happens when rainfall falls on a surface that can be overwhelmed by the amount or intensity of what is falling. Pluvial flooding can be a source of flash floods, according to experts, especially in times of increasing and concentrated “dumps” of rain falling on extensive impervious, paved surfaces at volumes that can overwhelm outdated stormwater infrastructure.
Tidal flooding near Milford Point. Photo by Steven Johnson.
The quiz below reveals more facts about flooding:
Questions:
- True/False: Creating greenways, or leaving open space with trees and other natural foliage, next to a river can protect property and save lives during heavy rain events.
- True/False: According to FEMA maps, close to one third of the property in Milford is categorized as a flood zone.
- True/False: Flooding only happens when it rains.
- True/False: It takes just 12 inches of rushing water to carry away most cars.
- True/False: One third of the flood insurance claims received by the National Flood Insurance Program are for damages occurring outside of high-risk flood areas.
- Choose the right word: Between 1996 and 2014, extreme precipitation events (increased/decreased) by 50 percent, according to research out of Dartmouth.
- True/False: High tide flooding is twice as frequent as it was 20 years ago.
- True/False: Across the US, the few states that do not experience floods are mountainous and more arid, like Wyoming and Utah.
Answers:
- True. Research shows a series of benefits to creating green spaces next to streams and rivers as conservation or “riparian” buffers. Among other things, such spaces can become urban amenities and recreation places.
- True, according to Milford’s city website.
- False. Tidal flooding, sometimes referred to as nuisance flooding, sunny-day flooding or king tide flooding, according to NOAA, can in the absence of rain inundate roads or flood the basements of shoreline residences, depending on the timing of the local tides and coincidence of a new moon or full moon. Some local residents check the height and timing of tides the way most of us check the weather forecast.
- True, according to a recommended NOAA webpage titled, “Turn around don’t drown.” In addition, according to that research, only 6 inches of rushing water can carry away an adult trying to cross a flood and 2 feet of rushing water can carry away an SUV or truck. The key is to stay out of floodwaters, whether walking or driving.
- True, according to floodsmart.gov. And those claims are only based on people who already have flood insurance; the actual percentage of damaged properties in the non-flood zones is certainly higher.
- Increased. That 2021 research also definitively tied the increases to climate change.
- True, according to NOAA. Factors contributing to tidal flooding include sea level rise due to global warming, land subsidence and loss of natural barriers like wetlands.
- False, according to NOAA and others. Every state experiences flooding. It turns out 99 percent of counties in the US have experienced a flood in the past 20 years, according to floodsmart.gov.
For essentials in preparing for floods and more, recommended sites include: Milford’s webpage on floods and hurricanes, offering disaster preparedness kits, emergency preparedness plans and protecting property from flood damage; the Trumbull’s, “Flood Response for Homeowners” a slight variation with a user-friendly layout; Consumer Reports’s “Plan Now for Potential Flooding” and the CDC’s “Preparing for Floods.”
Three local officials, also flood experts, who informed this column are acknowledged with thanks: Emmeline Harrigan, Fairfield Plan and Zoning director; Steven Johnson, Milford’s assistant public works director; and Mary Rose Palumbo, Milford inland wetlands officer.
Patricia Houser, PhD, AICP is a freelance writer and researcher focused on environment and sustainability.