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Although sea-level rise might seem to be a problem for only coastal residents, it is a danger that comes with stunning views and easy access the beach.
However, the Atlantic Ocean's higher altitude makes it more difficult for drainage canals that keep them dry in areas 20 miles away. Floodwaters remained in the southwest Broward areas for days after Tropical Storm Eta last year, partly due to the obstruction of drainage canals.
Barb Besteni, a resident of Miramar's far west Miramar said that it was quite scary. "I stepped out of my house into ankle-deep waters. It reached three-fourths of the driveway. It was the highest water level I had ever seen. It was frightening because I wasn't sure if the water would continue rising."
Her Sunset Lakes home is located at the Everglades' edge, but the Atlantic's higher elevation made it less efficient to drain.
She said, "It took very, very long to recede." It took two to three weeks for normal levels to return."
The South Florida Water Management District is responsible for the operation of the large canals that carry water into the ocean. This week, the district submitted a funding request for the state to fix the system. Its preliminary list of projects had a cost of over $1.5 billion. The pumps and other improvements will help to restore efficiency in a system that was built after World War II, but has become increasingly difficult to manage due to rising sea levels.
Carolina Maran, the district resilience officer for South Florida Water Management District, stated that ocean water can be more high than normal and so the gates are closed to prevent ocean water from entering. It was higher than usual during Eta. This means that we can't discharge to the sea, which has reduced our ability to prevent and address flooding."
Flood-control systems are overwhelmed by storms
Even though it's not a good time to suffer 15-plus inches rain, Tropical Storm Eta made South Florida a difficult place.
The ground was already saturated from previous storms. The king tide was also affecting the coast waters. This is a phenomenon where the sun and moon align to create the highest tides for the year. As sea levels rise, king tides get higher.
Gravitation is partly responsible for the wide canals that run through Broward County and Miami-Dade counties. They carry rainwater to oceans. Rainwater raises the canal's level on its inland side. Water managers then lift the gate that divides it from the ocean side. The water flows away and eventually reaches the Atlantic.
The Atlantic side may be higher than the Atlantic side, and the water won't move when it's lifted. Worse, the Atlantic side may be higher than the Atlantic side, which would mean that lifting the gate could allow ocean water to flow inland.
Staff at the South Broward Drainage District used tide charts to figure when they could open the gates or discharge water during Tropical Storm Eta.
Kevin Hart, the district director of South Broward Drainage District said that the downstream becomes equal to the upstream. Hart also oversees the canal system that feeds into larger canals that drain into ocean. We don't want the water to drain in, but we do want it to drain out. We have to close our gate.
"We looked at tide charts. Low tides will be at 2 o’clock, and at 5 or 6, we can see that the levels are dropping. We then open our gate once more."
Sea-level rise threatens the aging system
South Florida's drainage system was built largely in 1950s and 1940s. It has helped keep a once-swampy area of Florida dry.
It contributed to the Everglades' decline by flooding the area and drying it out at other times. It did what it was meant to, keeping the land dry for cities like Miramar and Pembroke Pines by moving swiftly rainwater through a network of canals to reach the ocean.
However, water doesn't move as fast and it sometimes doesn't happen all the time. People living in cities with no ocean views are discovering that the Atlantic Ocean's water level can have an impact on their homes.
Although flood-control devices are being installed in cities, they still need to be able to drain the water from the canals.
Angelo Castillo, Pembroke Pines commissioner, stated that no matter how much they do, if the canals aren't lowered so water can escape, then there is nothing we can do. "We can spend all the money we want on drainage, but they won't be able to access the canals because the canals don't have that capacity. Nothing we do will help them get water faster to the canals."
The rise in sea levels is largely due climate change, which has been caused by the pollution of cars, power plants, and other sources heat-trapping gases. According to a NOAA study, global sea levels have increased by 3.4 inches between 1993 and 2019.
According to the Southeast Florida Regional Climate Change Compact (representing local governments), sea levels will rise by 10-17 inches in South Florida by 2040, according to estimates.
The water management district proposed improvements to 23 drainage structures in Broward, Miami-Dade and Palm Beach counties. This is in an effort to modernize the system in the face of rising sea levels. They run from south Miami-Dade County up to the Hillsboro Canal which divides Broward and Palm Beach Counties.
Major projects include the installation of pumps that allow water to flow to the ocean side. This is necessary because the ocean is too high for gravity to move water. These projects can be costly.
If they are approved, the improvements could help homeowners pay their flood insurance bills. Better drainage could lower flood insurance rates and make it easier for more properties to obtain flood insurance.
The water management district seeks federal and state funding for the project. The district will begin designing the pumps and other improvements for the water-control structures along the canals that drain south Broward and northeast Miami-Dade as soon as funding is available.
Jennifer Jurado is responsible for climate-change planning in Broward County. She said that the improvements will help prevent residents from flooding in future storms. However, the region must find ways to preserve as much water as possible, rather than simply pumping it away.
She stated, "It's trying ensure that the system works at minimum as well as was intended." It's an important part of the solution. It can't be just pumped out. Because the rain that falls is what we use to supply water, we need to be able store as much as possible. It is important to store and capture that water in order to provide flood relief.
To learn more about the Major Everglades restoration projects that will be completed this year, click here
2021 South Florida Sun-Sentinel.
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