NAVIGATING THE INEVITABLE

Why We Should Prepare Today for Tomorrow’s Rising Turquoise Sea

Living on Miami Beach has its advantages — endless summers, walks on the beach in January, access to some of the finest restaurants anywhere and the city’s world-famous culture scene among others.

But over the course of the last decade, people who own property on this urban resort island have witnessed increased flooding amid dire predictions by climatologists that the turquoise waters of the Atlantic will continue to inch upward.

“When I drive around this city on a sunny day — and it’s king tide — I’m seeing water just percolating up,” observed Miami Beach Assistant City Manager Alina T. Hudak, referring to the non-scientific term people often ascribe to exceptionally high tides. “It’s an incredible phenomenon. Everybody should come to Miami Beach to see that.”

Unlike their parents, grandparents and great-grandparents, Miami Beach children born in 2020 are likely to be among the first generations who grow up witnessing the effects of sea level rise firsthand from cradle to grave.

Some Miami Beach residents may have already gotten a glimpse of the future back in November 2016 when an octopus popped up out of a drainage pipe at a South Beach parking garage during a king tide. The sea creature is believed to have been scooped up by a security guard and released into Biscayne Bay.

Unfortunately, the future still holds much uncertainty for the children born in 2020 at Mount Sinai Medical Center and other places like it during a year unlike any other.

By the time these children reach their sophomore year of college, the Atlantic is expected to have risen between 10 inches and 1.4 feet over levels recorded in 2000.

What’s more, the water level is predicted to rise between 1.75 feet and 4.5 feet — roughly the height of a 10-year-old child — by the time he or she celebrates their 50th birthday.

Should they be blessed with a long life — living to age 90 or more — he or she will have probably witnessed a sea level change of between 3.3 feet and 11.3 feet — about the length of a Fiat 500. No one knows with absolute certainty what sea level rise will look like and what solutions will prove most effective.

“This is a complex issue. We’re examining different solutions from both global and local perspectives,” acknowledged Miami Beach Chief Resilience Officer Amy Knowles. “Planning for a future we can’t quite see can be hard on human nature. How many cities in past history, said ‘let’s go ahead and plan land use and infrastructure for the next 50 to 100 years, and incorporate climate science and sea level rise?’ Coastal cities like ours are now asking ‘how do we plan for a city of tomorrow enjoying today?’ We host cities frequently from Boston to Honolulu, to observe and learn from how we are planning for sea level rise.”

In a recent questionnaire of 416 Miami Beach residents, 50% said they already witnessed flooding on the roads in front of their homes, including 29% who said they experienced flooding on their lawns. Twenty-seven percent of the residents who responded to the survey at the end of 2020 reported flooding in their garages. Thirteen percent reported flooding inside habitable areas of their properties.

Of those residents who said they experienced flooding, 45% said the water drained without damage while 32% said the flooding required renovation or replacement of some sort.

David Martinez, who serves as the city’s director of Capital Improvement Projects, told MB that homeowners should begin making changes to protect their properties from the potential flooding events they have already seen and those yet to come. This not only includes single-family homes but also the luxury condominiums and high-rise hotels throughout Miami Beach.

“If you have an existing property, to me they have to let their green areas hold some water,” he suggested. “They need to understand that’s OK.”

Miami Beach has been among the most active communities anywhere in the United States in terms of preparing for sea level rise. Streets in the Sunset Harbour neighborhood were the first to be raised to protect residents from sea level rise back in 2016. Similar projects in Indian Creek, Palm Island and Hibiscus Island are nearly complete. A street-raising project along West Avenue is expected to get underway this year.

“One of our biggest challenges is people fear that if you raise the road it increases their flood risk,” the city’s director of Public Works, Roy Coley explained. “That’s simply not the case.”

While we can all see the rain as it falls from the sky, we can’t see the vast amount of water that lies below the surface of residential and commercial streets in the city.

As the ocean continues to rise, the water under the streets will have to find another place to go, which is the quintessential challenge facing Miami Beach and other coastal communities.

“Seawater is pushing up water. Our groundwater has a thin layer of fresh water on top of the seawater,” Coley explained, referring to the layer of water that sustains the city’s trees and lush landscaping. “We need to preserve the freshwater lens.”

Homeowners have a number of options to reduce risk from sea level rise. These include the installation of rain gardens designed to hold water on properties for a day or so, to keep them from flooding. The ultimate solution would be to raise the elevation of each home, but that can cost $1,000 or more per square foot. Home elevation, however, is one of the only techniques that can result in significant flood insurance savings.

“I would have to say elevation does more than anything,” Coley shared. “If you elevate a property, you eliminate all of the other concerns about wet proofing and dry proofing.”

Knowles recommends homeowners begin the process of shoring up their homes by obtaining an elevation certificate to understand where their property lies with respect to sea level. Miami Beach neighborhoods sit — on average — at 4.5 feet above sea level.

“I think every case is unique, and every property is unique. It really depends on whether you have an older home, a newer home and the specific elevation of ground and home,” Knowles said. “The good news is there is a menu of options based on where you are at in life, and how long you see yourself living in the home.”

One measure that can be taken by all homeowners — and also one of the most affordable in comparison to changing the elevation — is dry floodproofing.

“This is where you take a very specific approach to keep water out of a low-lying property, and it’s something that can also be done to older properties. According to FEMA, a dry floodproofed structure is made watertight below the level that needs flood protection to prevent floodwaters from entering,” Knowles said. “Making the structure watertight requires sealing the walls with waterproof coatings, impermeable membranes, or a supplemental layer of masonry or concrete. It can include wall treatments and flood panels for doors.”

She said it is similar to installing hurricane shutters ahead of a big storm.

“You can put in rain gardens and bioswales to better contain ponding,” she said. “You can actually elevate your outside appliances — and even in your garage as well — to avoid damage.”

Residents might also consider regrading their yards and driveways to change the water flow.

“Private properties generally have to seek private funding to help make improvements,” she said. “In the same way that you are putting in your new kitchen or a new roof, you can absolutely go to your bank and take out a home equity loan, or other ways to finance these home improvements.”

A study by a leading climate consulting firm commissioned by the city of Miami Beach found that property values are higher in areas of higher elevation.

For example, in applying the peer reviewed model, the value of condominium units within 0.1 miles of Sunset Harbour rose in total value by about $41 million — or 12% — from before the project began until after the project’s completion in 2017 when holding all other variables constant.

The neighborhood has also avoided potential damage from tidal flooding due to road elevation.

“We have had more than 100 avoided flood events since January 2017,” Coley said in mid-November. “One hundred seventeen times as of today, the sea level has been higher than the old elevation that would have flooded those properties.”

Such street-raising projects take about two years to complete. They include new water and sewer lines as well as new street lights, according to Coley.

“We just do a complete rebuild when we undertake these projects,” he said. “There’s no way to avoid this pain. We have a situation where the sea is rising, and the climate is changing. The weather patterns are changing. It’s going to cost money, and it is going to be painful adapting. In 50 years, it may have to be done again.”

The same questionnaire of Miami Beach residents at the end of 2020 found that 77% would apply for a matching grant if available. The top items on their wish list appeared to be engineering assessments to learn how to reduce risk (49%), green infrastructure such as bioswales, retention areas and rain gardens (46%), yard and/or driveway grading (32%), dry floodproofing measures to make structures watertight (29%) and garage floor and/or yard elevation (28%).

It doesn’t matter whether everyone believes in the science behind climate change, or whether they simply get weary of cleaning up after one too many floods on their property.

“Anyone who is in denial, just has to come on a beautiful sunny day to Miami Beach during king tide, and see what’s happening,” Hudak added. “It’s very real.”

Questionnaire of Miami Beach residents at the end of 2020 found that the top items on their wish list appeared to be:

49%: Engineering assessments to learn how to reduce risk

46%: Green infrastructure such as bioswales, retention areas and rain gardens

32%: Yard and/or driveway grading

29%: Dry floodproofing measures to make structures watertight

28%: Garage floor and/or yard elevation

November 2020 photo taken at Alton Road & 56 Street

One Dozen Ways to Prepare Your Property for Sea Level Rise

1. Elevation certificates and flood mitigation assessments can help property owners determine the type of improvements needed.

2. Green infrastructure incorporates the natural environment, including rain gardens and bioswales to manage stormwater and increase biodiversity.

3. Cisterns and rain barrels capture water to reduce flooding and hold for later uses, including irrigation.

4. Replacing impermeable surfaces (like concrete) with permeable materials (E.g. grass and Florida-friendly landscaping) reduces the sheet flow of water and allows water to percolate naturally into the ground.

5. Appliance and equipment elevation helps avoid expensive water damage.

6. Dry floodproofing makes buildings watertight.

7. Garage floor and yard elevation can redirect water along the property away from the building.

8. Interior first floor elevation can prevent homes from flooding while preserving a home’s exterior.

9. Wet floodproofing can make uninhabited areas of properties resistant to flood damage.

10. Blue roofs can capture rainwater in a tank-like structure for later reuse.

11. Green roofs can capture rainwater and slowly release it through evaporation and plant use.

12. Flood barriers can prevent water from entering homes.