HILLSBORO BEACH, Fla. – In Hillsboro Beach, Mayor Irene Kirdahy explains a familiar problem faced by municipalities across South Florida.
“When there are King Tides, the intercoastal would actually top the walls,” says the former facilities engineer.
Hillsboro Beach is small and linear, stretching along A1A, the only road through the town.
“And one of the biggest things everybody asked is, ‘can we do something about the flooding?’ "
Kirdahy is also a representative with Broward Metropolitan Planning Organization (MPO). She submitted a proposal to fund MPO. The project also included new sewer lines. Her advice to other municipalities, if they want to consider a similar project, is to get moving.
She said it takes years working with the Florida Department of Transportation to secure the funding and begin the project.
Impassable surface flooding was becoming the norm. The town, working with FDOT, decided to raise the road. She said state engineers recommend it be raised six inches, but the town wanted more.
“We wanted a 30-year-old plan (to plan for sea level rise),” she said.
“It is now approximately two feet above where it was before and the years-long project is at the tail end of completion,” said Kirdahy.
When this week’s storms hit, the mayor said it was a major test for the road and it worked.
Miami Beach has been a regional leader in leveraging roadway elevation to alleviate chronic flooding; most notably in the Sunset Harbour area.
“In terms of success, the last King Tide when we are the most vulnerable because of sea level rise, we had 50 days that we were able to protect Sunset Harbor and the Indian Creek Drive area from getting flooded because of the rising tides,” said Joe Gomez, public works director, “because the roads were raised as a result of our projects.” Gomez said another important flood mitigation tool in the city’s arsenal was investing in robust drainage systems, which, he added “is incredibly helpful to counteract storm events.”
Ken Russell, who championed environmental policies when he was a Miami commissioner and now works in the private sector in sustainability consulting, says that it’s the municipalities that are “on the front lines of dealing with flooding issues. The reason why a storm drain ceases to function due to sea level rise is that it is not getting the headway to flush the water out of the pipes. Meaning that the outfall is not low enough anymore because water is already covering it. The water table has already risen, so by raising the roads, you add a little more gravity push to the water and it can get out.”
But, he said, there is a downside to this approach.
“You are doing massive construction on the public roads which may or may not be affecting private roads, the driveways, the homes, the businesses, so you need to take that all into account that you are not causing flooding where you don’t want it.”
Russell said there are short, medium, and long-term fixes for flooding:
Short: “Keep the pipes clean.”
Medium: “Raise the roads.”
But, Russell says, that for the long-term, “we have to think holistically, we have to think about the causes of the problem. Climate change and sea level rise is why our roads are failing, it is also why the storms are getting stronger and more frequent.”
He commented on the “once in 1,000 years” headlines that were prevalent this week.
“... It will be back, in much less, maybe even this year or less, so municipalities have to look at how they are addressing climate change, what they are doing for their built environment, not just the public roads, but the private buildings as well that are contributing to greenhouse gas emissions, our carbon footprint and making our situation worse.”
Monroe County ranks among the highest areas in the country impacted by tidal flooding.
Climate change, including but not limited to extreme weather conditions and sea level rise has prompted planners and officials to focus on strategies that, they say, “support a more resilient system.” The county maintains an estimated 311 miles of roads distributed among more than 1200 roadway segments throughout the county.
County officials say they are taking a proactive sustainability approach by merging climate change science and modeling, with transportation engineering and planning to develop a long-term roads adaptation plan based on design criteria, SLR projections, adaptation methodology, policy/financing evaluation, and public/stakeholder outreach.