Intense afternoon storms disrupted daily life across Tampa Bay this week, after rainfall deluged roads and overwhelmed drainage systems.
Daily thunderstorms are typical during the region’s summers, but a halted front and a boost of extra moisture in the atmosphere have led to strong, record-breaking rainfall. Over 3 inches of rain fell at Tampa International Airport in one hour on Tuesday, the most ever recorded during the time frame. The following day, nearly 5 inches of rain fell near Bear Creek in St. Petersburg in an hour.
“Quite simply, our stormwater system … is not prepared to instantaneously drain this amount of water in this short of a time,” Tampa Mobility Department Director Vik Bhide told members of the Tampa City Council on Thursday morning.
The rainfall, while anomalous, is likely a glimpse into the future. Climate change is expected to cause more frequent storms that will bring heavy rains. Officials say stormwater systems are not equipped to handle so much rain in such little time. And while infrastructure changes are planned in Tampa Bay’s major cities, they may be too costly, and not enough to manage these flooding rains.
How Tampa Bay has flooded
The first few days of this month have been the rainiest start in any recorded September in Tampa, according to the Southeast Regional Climate Center.
Robles Park, about 2 miles north of downtown Tampa, for example, experienced more than 5 inches of rainfall in two hours this week, according to Tampa data. That’s about 6% of the total rainfall the location has seen this year.
Nine full-time city employees worked into the night to vacuum drains, haul away debris and inspect neighborhoods for hazards. Leading the team was a 33-year veteran of the city who said he hadn’t seen this scale of flooding impact in “many, many years,” Bhide said.
In Hillsborough County, 16 staffers worked through the night battling floodwaters, said Kim Byer, assistant county administrator for Hillsborough’s Public Works.
Some parts of the county saw nearly 4 inches of water in a 30-minute window, she said.
“We had some folks sleep at some of the pump stations in order to make sure they were working properly,” she said.
Byer added that the county had received no reports of homes flooding, but that they were monitoring low-lying neighborhoods Thursday.
In St. Petersburg, nearly 5 inches of rain came down in just one hour Wednesday as measured by a rain gauge near Bear Creek. To compare, Hurricane Debby, which passed by the area as a tropical storm last month, poured 10 to 12 inches over 24 to 30 hours.
“We got half of that much rain in one single hour, and that unfortunately overwhelms our systems,” said Claude Tankersley, St. Petersburg’s public works administrator.
From storms on Tuesday, four manholes in northwest St. Petersburg were overflowing because too much water got into the wastewater system.
The city reported that 2,000 gallons of wastewater were discharged at 36th Avenue North and 66th Way North that flowed into Joe’s Creek. Tankersley said the overflows stopped around 3 p.m. Wednesday, but he said officials suspect they started overflowing again overnight.
Another overflow of 600 gallons on 52nd Avenue North near 11th Street was reported Thursday morning.
Infrastructure struggles
The rainfall that drenched St. Petersburg over the past few days was like “turning on a spigot” to “full blast,” Tankersley said.
Much of Tampa Bay’s stormwater infrastructure is not built to withstand such heavy downpours, officials said Thursday.
“The systems that we have in place that are not sufficient are not going to get improved anytime soon,” Bhide said of Tampa’s infrastructure. “It’s going to be many years.”
St. Petersburg’s systems are built like most others around the state: designed to handle 7.5 inches of rain in 24 hours. There are no plans to change that system, Tankersley said.
“We are not going to be designing our systems to handle 4 to 5 inches in one hour,” he said. “And the main reason we can’t do that is because it would be significantly expensive. … It’d be in the billions of dollars. And the cost to do that, I just don’t think that we’re prepared to commit ourselves to that kind of cost.”
Justin Tramble, executive director of Tampa Bay Waterkeeper, said high infrastructure expenses and adherence to statewide benchmarks shouldn’t be used as excuses for failing stormwater systems.
“We can’t just say, ‘Oh, well, that’s good enough for someone in Tallahassee,’” he said. “I would want my municipalities to take the lead in protecting our water quality.”
Tramble was on a seagrass research trip Thursday morning and noticed changes in salinity and color reflected in Tampa Bay after the rains. It’s a natural process of the estuary, he said. But stormwater and wastewater swept into the bay is not.
“Short term, everything seems to be OK, but, long term, who knows what that does?” Tramble said.
Sewage overflows, like the thousands of gallons spilled in St. Petersburg this week, likely contributed nutrient loads to local waterways, which can fuel harmful algae and deteriorate water quality.
“We can’t be OK with these dumps,” Tramble said. “We’re growing rapidly. We’re not the Tampa Bay region that we were in the 1980s, you know. So, we can’t have our infrastructure reflecting a 1980s population.”
Are stormwater changes coming?
As for long-term solutions in St. Petersburg, Tankersley said the city is following its stormwater master plan, which has identified over a billion dollars’ worth of work.
“St. Pete has experienced massive flooding events like this. It comes around once every 10 years or so,” he said. “There are times we’re going to get more rain than we can handle.”
Pinellas County plans to spend more than $250 million by 2030 on flood control and surface water projects and storm sewer rehabilitation, according to the county’s proposed budget for the fiscal year starting in October.
Among them are the restoration of Joe’s Creek in Lealman and Kenneth City, which is still being designed and expected to cost more than $60 million; major drainage improvement efforts in Crystal Beach and near Bay Pines; and the transformation of the former Baypointe Golf Course in Seminole into a 40-acre conservation and stormwater-management area.
Tampa is in the middle of the largest infrastructure project in its history: a 20-year push to fix its aging pipes and overhaul the city’s sewage and water plants. The $2.9 billion program, dubbed PIPES (Progressive Infrastructure Planning to Ensure Stability), dwarfs the $251 million stormwater fix during former Mayor Bob Buckhorn’s tenure, the Tampa Bay Times previously reported.
Still, residents across the city were immobilized Wednesday, as drains clogged and streets filled, water seeming to have nowhere to go.
Tampa has seen rapid growth in recent years. Once-sleepy neighborhoods are now awash in new construction.
Future development, Bhide said, needs to be focused in areas away from coastal high hazard areas and attentive to evacuation routes.
“There are strong headwinds,” he said, “but it’s not all doom and gloom.”
More rainfall is expected through Friday, according to Ali Davis, a meteorologist for the National Weather Service’s Tampa Bay office. However, the weekend could bring a break from the heavier storms. While thunderstorms are still expected next week, they likely won’t bring the same intense rains that have washed over Tampa Bay the past few days.
Times staff writers Colleen Wright, Jack Prator, Jack Evans and Olivia George contributed to this report.