In 2020, picturesque coastal towns across the US faced an adversary like no other: unprecedented high-tide flooding that left thousands displaced and homes swallowed by the sea. But what exactly is behind this watery onslaught? And how can you stand prepared against it? Dive with us into these murky depths: what is coastal flooding? What is the warning system to help you prepare? And what are the life-saving steps you should take when the waves come a lapping?

Unraveling the Mystery: What is Coastal Flooding really?

Imagine your familiar streets turning into muddy rivers, the relentless sound of rushing water echoing in your ears. This is the reality of coastal flooding. It occurs when dry, low-lying areas are submerged by sea water, a phenomenon triggered by:

• Storm Surges: Think of it as a tidal wave, an abnormal rise in sea level accompanying fierce storms or hurricanes.
• High Tides: Nature’s rhythm, especially pronounced during ‘king tides’.
• Tsunamis: Massive sea waves birthed by underwater disturbances like earthquakes.
• Rising Sea Levels: Our planet’s silent alarm, linked to global warming and melting polar ice caps.

What Causes of Coastal Flooding in the U.S.?

Let’s dive into the tempestuous combination of factors causing coastal flooding in the U.S.:

1. The Silent Stalker: Rising Sea Levels: As our planet warms, ice caps weep, pouring their millennia-old tears into the oceans. This slow, steady rise in sea levels stealthily inches water closer to our doorsteps.
2. The Fury of Storm Surges: Picture a hurricane, its winds howling with rage, pushing walls of water towards our shores. This sudden onslaught, this storm surge, is a prime culprit of coastal flooding.
3. The Drama of King Tides: The moon and sun create tides. Sometimes, they pull the strings a tad too hard, giving birth to ‘king tides’—nature’s own high-water spectacle that can flood our coasts.
4. The Deluge from Above: When the heavens open up with relentless rain, rivers swell, and their waters, with nowhere else to go, rush to the embrace of the sea, causing coastal areas to drown in the process.
5. Tsunamis: The Ocean’s Thunderous Charge: Birthed by the Earth’s restless movements, tsunamis are colossal waves charging towards the coast, bringing with them the might and fury of the deep blue.
6. The Sinking Lands: In some places, the very ground beneath our feet is betraying us, sinking slowly, making it easier for the sea to claim its prize.
7. Man’s Ambition: Our quest to be closer to the sea, building homes and cities, often weakens nature’s own barriers, leaving our coasts exposed and vulnerable.

In the grand theater of nature, the U.S.’s Gulf Coast and Eastern Seaboard often find themselves on the front row, witnessing the full spectacle of coastal flooding’s causes.

Is coastal flooding getting worse?

Flooding along the U.S. coastline is happening more often. There is a long list of coastal towns now that have seen more flooding since the 1950s. And flooding is happening even faster now, especially on the East and Gulf Coasts.

Here’s something particularly interesting.

The East Coast of the US gets flooded the most. The number of times it floods has gone up significantly.

Since 2011, Boston, Massachusetts, has had the most flood days, with water going over the usual level about 13 times a year. Bar Harbor, Maine, and Sandy Hook, New Jersey, are next on the list. In many of these places, flooding is now happening five times more than it did in the 1950s.

High-tide flooding

High-tide or ‘sunny day’ flooding is also predicted to get a lot worse by 2030.

High-tide flooding is when the sea level rises higher than usual, even on sunny days without any rain. It’s coastal flooding from sea level rises.

Think of it like the ocean having too much water and spilling some of it onto our streets or coming up from drains. This kind of flooding is happening more often because the sea level has been rising for years.

A recent study found that U.S. coastal areas are seeing this kind of flooding way more than they did 20 years ago. In fact, it’s doubled! And this is expected to keep happening in the future. Some places along the Southeast Atlantic and Gulf coasts have even set new records for this kind of flooding.

NOAA has been keeping track of water levels. They found that some places in Texas and Florida are seeing a lot more flooding than usual. South Carolina and Georgia’s coasts are also facing this problem.

Between May 2020 and April 2021, three places – Galveston and Corpus Christi in Texas, and Bay Waveland in Mississippi – had over 20 days when the tides were super high and caused flooding. This is crazy because, 20 years ago, these places would only flood like this for 2-3 days in a whole year!

Other places like Dauphin Island in Alabama, Grand Isle in Louisiana, Pensacola and Trident Pier in Florida, Charleston in South Carolina, and Port Isabel, Rockport, and Panama City Beach in Texas also had more flooding. They saw 10 to 20 days of high tides causing floods. Back in 2000, these places would usually only have this kind of flooding for 0-2 days in a year.

But not everywhere is seeing this big jump in flooding.

In places where the sea level hasn’t risen as much, like Hawaii and the West Coast, the increase in flooding isn’t as big.

What does this mean for you?

If you’re located on the East Coast of the US, it’s time you learn about coastal flooding – what to expect, the warnings and what to do. Before it comes lapping at your doorstep.

So let’s do that in a 5 minute read.

Coastal Flood Hotspots: Is Your Home at Risk?

From the sun-kissed beaches of Florida to the bustling streets of New York City, coastal flooding is an indiscriminate visitor. Especially vulnerable are:

• Florida: Those breathtaking sunsets come with a price, especially in the Keys.
• Louisiana: The Mississippi Delta region, a dance floor for the waves.
• Eastern Seaboard: The Carolinas, Virginia, and Maryland are regulars on flooding’s guest list.
• Northeast: New York City and New Jersey, where skyscrapers meet rising tides.
• West Coast: California’s golden coast, occasionally silvered by floodwaters during El Niño events.
• Barrier Islands and Estuaries: Nature’s frontline, bearing the brunt of the onslaught.

If you live in one of these areas or are moving to one, make sure you understand the flood zone systems and which flood zone requires flood insurance.

You can also help reduce your risk of loss by preparing yourself and your home for flooding and packing a Flood Emergency Kit.

Navigating the US Coastal Flood Warning System

The National Weather Service (NWS) plays sentinel when it comes to coastal flood advisories, ensuring you’re never caught off-guard. Here’s your map to their alerts:

• Coastal Flood Watch: Think of this as your yellow traffic light, signaling potential flooding in the next 12 to 48 hours.
• Coastal Flood Warning: The red light. Flooding is either knocking at the door or has already barged in. Act now!
• Coastal Flood Advisory: A gentle nudge about short-term, minor flooding threats. Not life-threatening, but certainly toe-wetting.
• Flash Flood Warning: The unexpected deluge, usually from torrential rainfall or a dam’s breach. Immediate action is paramount.

You can check if there is a coastal flood warning for your area at this NWS weather alerts webpage.

When the Waves Come Ashore: The Reality of Coastal Flooding

As the tide creeps in, a series of dominoes topple:

• Rising Waters: A slow invasion, as waters inch inland.
• Inundation: Roads become rivers, homes turn into islands.
• Erosion: Beaches and dunes, nature’s barriers, are nibbled away.
• Saltwater Intrusion: That refreshing glass of water? It might just get a salty twist as saltwater sneaks into freshwater sources.
• Infrastructure Crumbles: Roads fracture, bridges wobble, and buildings bear scars.
• Nature’s Balance Tips: Delicate coastal ecosystems, like marshlands, are thrown into chaos.

The Coastal Flood Alarm Sounds: What’s Your Next Move?

When the NWS sounds the alarm, it’s game time. Here’s your 6-step playbook:

1. Stay Informed: Keep one ear to the ground and one eye on the NWS website.
2. Evacuation: When the call comes, heed it. Your belongings aren’t worth your life.
3. Safety First: If it looks like a flood, don’t walk or drive through it. Cars aren’t boats, and 12 inches of water can set them afloat.
4. Fortify Your Fortress: Lift those electricals, turn off utilities and lock up safe.
5. Emergency Kit: Your lifeline. Stock it with water, food, meds, and critical documents.
6. When the water recedes: Return when the coast is clear, literally. Wait for authorities to give you the go ahead. Here’s how to clean up after a flood safely, if your home is inundated.

Where to go in a coastal flood evacuation

If you’re faced with a coastal flood advisory, what is your path to safety? Your beacon in the storm? Here are 9 top tips to navigating and escaping rising flood waters:

1. Journey to the Heartland: Leave the roaring coast behind and embrace the calm of the inland. The further you venture from the ocean’s grasp, the safer you’ll be.
2. Go up for Safety: Seek the sanctuary of higher ground. Rise above the flood’s reach.
3. Safe Havens Await: Towns and cities have thrown open the doors of schools and community centers, transforming them into bastions of safety. Listen to the local sirens and emergency broadcasts for guidance.
4. The Comfort of Familiar Faces: Seek refuge with loved ones living away from the coast. Their homes could be your safe harbor.
5. A Night Away: Consider a hotel or motel further inland to retreat from the raging waters.
6. Deceptive Roads: The path may seem clear, but remember: even a gentle stream on the road can hide a torrent beneath. Heed the age-old wisdom: “Turn around, don’t drown.”
7. Follow the Guiding Stars: Trust in the routes set by local heroes and officials. They’ve charted the safest course through the storm.
8. Whispers in the Wind: Keep your ears tuned to the radio’s hum or your smartphone’s chime. They bring tales of safe passages and updates on the flood’s dance.
9. Arm Yourself with Knowledge: Chart your escape, pack your evacuation kit, and know the way out before the first wave crashes.

In a nutshell

Coastal flooding, a rising concern along U.S. shores, happens when the ocean’s waters surge onto land, often due to high tides, storms, or long-term sea level rise. From advisories that give a gentle heads-up about minor flooding to urgent warnings about significant flooding, meteorologists use a range of alerts to keep us informed. As the ocean’s creeps further onto our streets and homes, it’s crucial if you live in coastal areas to stay updated with local weather reports and advisories. If you live near the coast, always be prepared: know your evacuation routes, have flood emergency kit ready, and remember—when in doubt, seek higher ground.

FAQs