The cost of the rising tide will be “painful” and “sobering.”
Half of Holmes Beach will be inundated by coastal waters by the year 2040 if nothing is done to stem the tide through improved stormwater management and other solutions, according to city engineer Lynn Burnett.
Storm evacuation routes would be swallowed up, too, Burnett told city commissioners at their April 10 work session.
Since 1984, the water level surrounding Holmes Beach has risen 8 inches, according to Burnett, and it’s not expected to recede.
“This isn’t a fallacy,” said Burnett, a Holmes Beach native. “This isn’t some theory. This has nothing to do with the global-warming dispute. It has to do with the reality of times that I’ve watched high tide come over our existing seawalls and flood our evacuation routes.”
Commissioner Jim Kihm asked how much water will be in his yard by the year 2060.
“Is it all dry land?” Kihm asked. “Do we still have wet streets?”
Holmes Beach is a coastal community bounded on the west by the Gulf of Mexico and the east by Anna Maria Sound and Sarasota Bay. Yet its antiquated stormwater system is inadequate to handle runoff within the incorporated limits, said Burnett.
Making the problem more acute, the three Anna Maria Island cities are millions of dollars short of implementing needed defenses. You need revenue sources to pay for solutions, she said.
“The goal is to establish a framework for a system that will last for 100 years and that will not be a burden on taxpayers,” Burnett said.
The Holmes Beach defense system against sea-level rise includes a 7-foot dune system on the Gulf of Mexico, interconnected valves in storm drains and seawalls.
An estimated $111,000 worth of WaStop valves, which prevent backflow, flooding and sewage odor in pipes, were just installed along Marina Drive, Burnett said, and more are on the way.
“We’re on a good track if we stay the course,” she said.
All seawalls will require a 1-foot cap addition as they are replaced or repaired. It’s an expense looming for every island property owner, said city attorney Patricia Petruff.
“Any seawall in place on this island will need to be replaced within the next 15 years,” said Petruff.
Most importantly, Holmes Beach must improve its handling of stormwater runoff, Burnett warned, or risk catastrophic flooding in the future.
“If we continue to let all the water run down the hill to Sarasota Bay, we will never solve the problem with sea-level rise,” Burnett said. “And our flood-insurance rates will go up. So we have to do something upstream at each property so we can capture the water running off that roof at its source.”
The plan is to remove the impervious materials that impede drainage and contribute to flooding, and replace them with pervious French-drains that replenish local water tables and alleviate flooding, she said.
“All three cities have come together and are moving forward in this same fashion,” Burnett said. “There’s a measurable benefit to every property owner for these efforts we’re undertaking.”
Benefits of the strategy include dry roads, safe evacuation routes and improved walking, biking and driving conditions, Burnett said. But it will only buy a respite of about 20 years before an islandwide process of incremental elevation of roadways, driveways and sidewalks will be required, she said.
The city stormwater utility assessment fee will help pay for improvements. It is budgeted to accrue $216,000 this year.
A Southwest Florida Water Management District grant matches every dollar Holmes Beach spends on stormwater improvements.
Commission Chair Judy Titsworth said the “flood tax” may need to be increased.
Private property rights will be trumped by the city’s responsibility to protect the citizenry, Burnett said. The city reserves the right to undertake changes or terminate permitted activities without risk or liability of any kind, particularly involving driveways.
“There are some painful things in the process,” she said. “There are people we need to patiently work with one-on-one. It’s a delicate process.”
Kihm said he wants to ensure residents are not faced with confrontational city ultimatums.
“There’s some flexibility in doing that,” Kihm said. “I think that was something that was missed the last time we had a discussion about driveways. It sounded like it was ‘my way or the highway.’”
Burnett said she would bring comprehensive plan amendments to the commissioners soon in order to start implementing short-term solutions with funding already in place.
“I know it’s a little bit sobering, but we have a responsibility, a huge responsibility,” Burnett said.
The commission will next meet at 6 p.m. Tuesday, April 24, at city hall, 5801 Marina Drive.