About 40,000 gallons of sewage spills in two incidents related to air release valves

Events occurred in Bee Ridge and Central County water reclamation facility service areas

This map shows the location of the Camphor Avenue sewage spill in Sarasota. Image courtesy FDEP

On back-to-back days early this week, Sarasota County workers responded to two sewage spills, with a July 26 incident involving about 35,000 gallons that overflowed into a stormwater ditch leading to Red Bug Slough Lake, staff reported to the Florida Department of Environmental Protection (FDEP).

Altogether, that report said, approximately 10,000 gallons of the effluent was recovered.

In the other incident, which occurred on July 25, approximately 5,000 gallons of raw wastewater flowed into a roadside swale, according to the county’s notification to FDEP. About 3,000 gallons of sewage was recovered, that report pointed out.

Both situations were linked to air release valves, the FDEP notices said.

In the July 26 incident, staff reported that utility crews received a call about 8:30 a.m. regarding a sanitary sewer overflow at a manhole in front of the residence standing at 4938 Camphor Ave., which is east of Swift Road and Riverview High School.

As workers investigated that situation, the FDEP notice explained, they found that an air release valve (ARV) had suffered a mechanical failure, which led to the sewage spill.

“Sampling has already begun,” the report noted. The clean-up process and notifications of surrounding property owners and residents were “proceeding per protocol,” the report added.

This is an aerial map showing the location of the Camphor Avenue incident, marked by the red balloon. Image from Google Maps

“The ARV will be scheduled for replacement,” the report also pointed out. The type of mechanical failure identified in this incident had been documented in another recent event involving an ARV, the report noted. “County staff is working with the manufacturer to determine a possible solution to prevent future incidents,” the report said.

The spill was halted at 11 a.m., the report added.

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.

The county facility associated with the Camphor Avenue incident is the Bee Ridge Water Reclamation Facility, which is located at 5550 Lorraine Road in Sarasota.

County utility crews were alerted to the July 25 situation at 12:30 a.m., that report noted. A caller reported that water was “bubbling up out of the ground” between U.S. 41 and Settlers Drive in Nokomis. The area is northwest of Lake Village and southwest of the Bellacina by Casey Key residential development.

This map shows the location of the spill in Nokomis. Image courtesy FDEP

“Upon investigation, staff discovered that an underground ARV had a mechanical failure and was leaking sanitary sewage,” that report also pointed out. “County crews were able to quickly isolate the ARV, stopping the incident [at 2:15 a.m.],” the report added.

“A new ARV will be scheduled for installation this week,” the report continued. “No surface waters were impacted,” the report said, so no sampling was required. As in the Camphor Avenue incident, the clean-up and notifications were proceeding per protocol, the report added.

That incident occurred in the Central County WRF service area, the report noted.

The Central County facility is located on Palmer Ranch.