Technological advances propel St. Pete’s stormwater plan
Communities across the state and nation now follow St. Petersburg’s lead as officials incorporate new technology into the Stormwater Master Plan to mitigate flooding.
However, new modeling software requires additional funding, bringing the project cost to nearly $3 million. City council unanimously approved a $599,773 appropriation during its May 4 meeting.
The money supports new database development new after the Environmental Protection Agency (EPA) updated its software. Brejesh Prayman, director of engineering and capital improvements, said St. Petersburg is among the first to utilize the new tech, which could also save residents money on flood insurance.
“The level of detail and the best practices we’ve developed in this is leading a lot of industries and public agencies,” Prayman said. “There have been numerous technical papers already published on the work we’re doing so far.
“Our model is within 1/100th of a foot of elevation – we’ve already utilized this.”
He explained that a resident reported an intersection inundated with water. The city’s models stated that the location shouldn’t flood and, “sure enough,” something had obstructed the drainage system.
Prayman noted city staff has leveraged in-house data collection to receive over $11 million in grants. He said, “Essentially, the project is already paying for itself with the investment that we’ve made.”
In 1994, St. Petersburg’s original stormwater plan recommended 338 projects with an estimated cost of $610 million, adjusted for inflation in 2019. City officials have completed about a third of those for $211 million.
City officials began using detailed data gathering and analysis using 3-D laser scanning, or LiDAR, in 2018. They are now increasing community involvement and coordination with the Southwest Florida Water Management District (SWFWMD) and accounting for sea level rise.
Prayman said he has met with the Tampa Bay Regional Planning Council, Florida Flood Hub and Tampa Bay Estuary Program’s leadership while establishing the latest updates. “So I feel very comfortable with what we are providing here,” he added.
“This master plan is being looked at regionally and nationally … as the best management practice as how to develop a master plan.”
Prayman relayed that the city operates 555 miles of pipes, roughly the distance to Myrtle Beach, South Carolina. St. Petersburg’s stormwater sub-basins have increased from 1,186 in 1994 to 12,628.
He said that allows officials to focus on a two or three-block section when a resident reports an issue rather than checking everything within a 20-block radius. Prayman explained that this leads to development and cost efficiencies.
The Stormwater Master Plan is also an element of the Community Rating System, which provides resident insurance benefits. With a current rating of 5, those living in a floodplain can save 25% on market rates.
Prayman relayed that if the city successfully implements the new plan in coordination with SWFMD, it could achieve a rating of 4 and provide a 30% discount. In addition, he said the latest modeling software would enable better storm forecasting and help improve water quality throughout the area.
“It’s like going from a dot-matrix printer to a laser printer,” Prayman said.
However, Councilmember Ed Montanari noted the “tremendous” amount of money spent on the plan since 2016. The latest funding request is part of a seventh amendment.
Project officials continue gathering public input and will present their final service recommendations to the council this summer. Montanari called it “illogical” to make that decision without seeing a draft plan after six years of development.
“I have a feeling this is going to be an extremely expensive infrastructure program,” he added. “This is going to be a 30-year look into the future, and that is why I want some more information.”
Prayman said gathering the new modeling data and presenting corresponding options to council members according to cost is more efficient. He also relayed that the pandemic and an issue receiving mandated LiDAR data from SWFMD caused separate eight-month process delays.
The delays necessitated another public engagement round, and Prayman said those elements “add up.” While he agreed that the project “has taken a while,” he noted the city received nearly three times its $3.5 million investment in grant funding.
“I’m voting for this amendment that’s before us today,” Montanari said. “I’m just saying we have a huge decision on May 25, and we don’t have data.”
Prayman relayed that he would extract new information from the “intricate” models and present it to council members during the May 25 Committee of the Whole meeting. The goal is to have a final plan ready for implementation by the winter.