Staff Writer
Experts warn they could become hazardous
The shimmering stormwater ponds throughout Duval County may look inviting, but City leaders want to make sure citizens know not to jump in.
That’s for safety reasons, now and later.
Jacksonville Waterways Commission Chair Reginald Brown requested information at the commission’s June meeting about the safety requirements for stormwater ponds, but he also was made aware of the hazards that they may pose in the future.
The safety requirements can be found in a city ordinance that specifies slope and fencing requirements.
The potential future hazards of the stormwater ponds are a little murkier to explain.
“They could end up being hazardous waste dumps in the future,” said Quinton White, executive director of the Marine Science Research Institute at Jacksonville University and a consultant to the commission.
“Without a plan for treating them, it will be a problem left for our grandchildren to deal with.”
While a spokesperson for the St. Johns River Water Management District didn’t believe the ponds posed an immediate threat, he said the ponds are not recommended for many recreational purposes.
“While there hasn’t been any research to show that the sediment in the ponds is hazardous, we still don’t recommend people consume fish caught or swim in stormwater ponds,” said David Miracle, permitting director of the Jacksonville Service Center of the water management district. “Catch and release fishing is fine, as well as canoeing.”
Miracle also has reviewed research that revealed that there has been small, incremental buildup on the bottom of the ponds and considers White’s point valid in the next 20 to 30 years.
“I would partially agree with him on that statement,” said Miracle, referring to White’s statement that the ponds will be a problem for future generations to deal with if a plan is not developed to maintain them.
“We do want to recognize that they do need maintenance and possibly, many years down the road, there may be a need for some type of dredging to remove some of that accumulated sediment,” he said.
There are about 1,200 stormwater ponds in Jacksonville and that includes both city-maintained and privately maintained ponds. The city is responsible for maintaining about 195 ponds.
The ponds are used to prevent streets and neighborhoods from flooding and to reduce the amount of sediment and contaminants entering area rivers and tributaries.
Untreated stormwater runoff is now considered the state’s leading source of water pollution, according to the water management district. The increase in pollution has been attributed to rains that flow over roofs, roads and lawns and carry contaminants, including fertilizers, pesticides, motor oil and heavy metals.
According to the City’s Public Works Department, there are generally two types of stormwater ponds that serve to control stormwater:
• Detention (wet) ponds. A detention, or wet, pond is a pool of water into which rain (stormwater) is directed, held and eventually discharged into the local drainage systems. These ponds provide stormwater treatment, where contaminants are allowed to settle to the ground so the water that enters the drainage system is cleaner than when it entered the pond.
• Retention (dry) ponds. Conversely, a retention, or dry pond, does not permanently contain water nor is the water discharged into a greater drainage system. It remains in the pond until it either evaporates or is absorbed into the ground.
Stormwater ponds are considered a “Best Management Practice” by the Florida Legislature and are a part of stormwater management requirements for new developments. The City of Jacksonville encourages the construction of the ponds with its “Permitted Stormwater Pond Credit” that gives developers a 30 percent credit on stormwater fees.
Sources agreed that stormwater ponds do a good job of keeping contaminants out of area waterways.
“They serve a useful purpose,” said White, “but they are not and should not be considered maintenance-free forever. At some point, we are going to have to go in and take care of them. This may involve dredging out the bottom soil and putting it into a lined landfill where it won’t leech out.”
White would like Jacksonville to take a more proactive approach to managing the ponds, instead of waiting until sediment reaches critical mass.
“It will become a more noticeable problem in the future,” said White. “I suspect we, as a community, will develop testing procedures, but it’s not cheap to test for heavy metals.
“It’s a philosophical dilemma. You know it’s coming, but not to what extent,” he said.
The water management district may be charged with permitting and regulating the ponds, but it is the responsibility of the City for the public ponds and, mostly, homeowners associations for private ponds to maintain the bodies of water.
Council member Brown would like to see the entity that creates the pond contribute to its maintenance.
“A lot of these ponds are in my own backyard in District 10,” said Brown. “It would be irresponsible of us to not have a plan in place for the cleanup of these ponds. We need to have the developer contribute to that cleanup. We will be discussing how to go about that in upcoming meetings.”
The next Jacksonville Waterways Commission meeting is tentatively scheduled July 8, but that meeting depends on the availability of the new members of the commission who are appointed by new Council President Jack Webb.
He recently selected Council member John Crescimbeni to chair the Commission during the next term. Crescimbeni will replace Brown as chair at the July meeting.
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