County’s Public Utilities Department at work on means of providing extra protection to air release valves to prevent sewage spills

Commissioner Ziegler voices concerns about preventable incidents leading to state fines

Mike Mylett is director of the Sarasota County Public Utilities Department. Photo courtesy Sarasota County

The director of Sarasota County’s Public Utilities Department has told the County Commission that his staff is working on extra measures to protect air release valves (ARVs) that are vulnerable to being struck by vehicles, leading to sewage spills.

Commissioner Christian Ziegler raised the issue during his board’s regular meeting on Sept. 9. He voiced frustration with recent reports the county has had to file with the Florida Department of Environmental Protection (FDEP) regarding such incidents.

As he read those reports, Ziegler said, it seemed to him that “all of a sudden, boom!” the ARVs were hit, resulting in “a massive spill that is totally preventable.”

An incident report county staff filed with FDEP on Sept. 7 noted that a car appeared to have run over an ARV near Sun Bonnet Boulevard on Honore Avenue that evening, resulting in approximately “1,000 gallons of fully treated reclaimed water” spilling onto the street and into a stormwater structure connected to a nearby pond. The report added that crews recovered about 300 gallons of reclaimed water mixed with stormwater from the stormwater structure and ditches.

An FDEP map shows the location of the Sept. 7 sewage spill associated with damage to an ARV. Image courtesy FDEP
This aerial view shows the location of the stormwater pond affected by the spill on Sept. 7. Image from Google Maps

As per county protocol, the report noted, clean-up efforts were underway, notifications of the incident would go out to the surrounding properties, and samples of the pond water would be taken.

That incident was reported at 5:45 p.m. on Sept 7, with the county crew’s initial response ending at 7:45 p.m.

The ARV in that situation is part of the system associated with the Central County Water Reclamation Facility on Palmer Ranch.

In a blog, Crane Engineering explains, “Air release valves are installed at the highest points in a pipeline where air naturally collects. Air bubbles enter the valve and displace the liquid inside, lowering the liquid level. When the level drops to where it no longer buoys the float, the float drops. This motion pulls the seat away from the orifice, triggering the valve to open and vent the accumulated air into the atmosphere. As the air is vented, liquid re-enters the valve, once again buoying the float, lifting it until the seat presses against the orifice, closing the valve. This cycle automatically repeats as often as necessary to maintain an air-free system.”

Crane Engineering has offices in Wisconsin and Minnesota, its website says.

This diagram illustrates how an ARV works. Image from Burgess & Niple, presented to an Ohio Water Environment Association conference

During the Sept. 9 County Commission meeting, Ziegler also mentioned a recent report regarding an incident in which a mower hit an ARV. “I don’t know how that happens,” he said.

His primary concern, Ziegler continued, is the potential for the county to have to pay fines for the resulting sewage spills, as a result of a new state law Gov. Ron DeSantis recently signed.

As The Sarasota News Leader reported last week, state Sen. Joe Gruters of Sarasota and Rep. Randy Fine of south Brevard County sponsored House Bill 1091, which includes a 100% increase in penalties for sanitary sewer overflows and an across-the-board 50% increase for all other environmental fines. The measure allows for a daily fine until an issue has been remediated or until a Consent Order with the Florida Department of Environmental Protection (FDEP) has been put in place to address the violation.

“I would like to see a plan to protect those [ARVs]” that seem most vulnerable to damage, Ziegler told Public Utilities Director Mike Mylett on Sept. 9. “Some things in Publix parking lots are protected more than these ARV valves. … Maybe it’s dropping a cement block in front of them, so cars don’t hit ’em and mowers don’t hit ’em.”

Commissioner Christian Ziegler. File image

Ziegler added, “I think we need some sort of county comprehensive plan” to prevent such incidents, because “we get blamed for the spill …”

County Administrator Jonathan Lewis responded that he had spoken with Mylett just that morning about those concerns.

Approximately 5% of the county’s ARVs have redundant protection, Mylett explained. Those are structures that have been hit multiple times in the past, he added.

Staff has compiled a list of others in rights of way, which have high potential for damage, Mylett continued.

As for a lawn mower striking an ARV: Mylett pointed out, “These are the big tractors you see driving down the sides of the roads. So it’s something significant that takes these ARVs out.”

His proposal, Mylett told the commissioners, is to use rocks or bollards around the vulnerable ARVs.

Lewis added of Mylett, “He’s also assigned a point person” in the department to work on measures to protect the devices.

“A good portion of [the county ARVs] are already underground,” Lewis noted.

“I love hearing that,” Ziegler replied. “I’m not a sewer/water guy,” he added. Whatever staff can do to prevent damage to ARVs would be appreciated, Ziegler said.

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