Contractor struck air release valve in working on Cattlemen Road project on Oct. 28, while pipeline failure in Prestancia resulted in second incident
In separate incidents over the past two weeks, approximately 20,000 gallons of raw sewage spilled onto a construction site on Cattlemen Road, and 30,000 gallons of fully treated sewage, for use as reclaimed water, spilled on the roadway and into a stormwater structure at the intersection of Prestancia Boulevard and Mirada Way, just west of McIntosh Road and northwest of Palmer Ranch Parkway, Sarasota County Public Utilities Department staff has reported.
Both incidents occurred in Sarasota, according to county staff reports filed with the Florida Department of Environmental Protection (FDEP).
In the first incident, reported early in the afternoon of Oct. 28, county workers responded to a report of a possible sewer spill at 6000 Palmer Blvd., the site of the county’s Cattlemen Road project. When the crew members arrived, the report said, they found that a private contractor’s employees had damaged an air release valve (ARV) inside a concrete vault.
County staff was able to isolate the ARV to stop the spill, the report explained, and then staff recovered about 18,000 gallons of sewage from the site. The clean-up work and notifications of affected property owners were proceeding according to county protocols, the report added.
The site of the spill was between Interstate 75 and South Packinghouse Road, just south of Palmer Boulevard, and FDEP graphic showed.
No water sampling was necessary, the report noted.
As county staff explains in its recent Construction — One Week Look Ahead reports, a contractor has been widening Cattlemen Road to four lanes from 600 feet north of Bahia Vista Street to Packinghouse Road, including the intersection at Palmer Boulevard. The initiative includes the reconstruction of South Packinghouse Road from south of Palmer Boulevard to Cattlemen Road. Sanitary sewer improvements are part of the undertaking, as well, the reports explain.
County workers have scheduled the replacement of the damaged ARV at the spill site “when parts are available,” the report said. Staff also planned to file an insurance claim to cover the expense of the response to the incident, the report pointed out. Further, the report said, if FDEP fines the county for the spill, county staff would seek to have the contractor cover that payment.
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.
That incident was reported at 12:40 p.m. on Oct. 28; it took the workers until 3 p.m. to complete their work at the site. The spill involved the service area of the county’s Bee Ridge Water Reclamation Facility (WRF), the report noted.
The second incident was reported at 11:45 a.m. on Nov. 2, that FDEP report said. In that situation, the Public Utilities Department sent a crew to the Prestancia subdivision in response to a report of a water leak, the document noted.
When the workers were investigating the situation, the report continued, they learned that an 8-inch reuse water main pipeline had failed. They were able to isolate the broken section of that pipeline to stop the leak until a permanent repair could be scheduled. However, the workers were able to recover only about 3,000 gallons of the 30,000 gallons of reuse water, the report said.
Initially, the workers believed that surface waters had been affected, which would have necessitated water sampling in accord with county protocols, the report noted. However, after further inspection, county crew members discovered that none of the effluent had entered any waterways; therefore, sampling was not required.
It took the county workers until 9 p.m. to resolve the issues at the site, the report added.
That spill involved equipment associated with the Central County Water Reclamation Facility, the report pointed out. That plant is located on Palmer Ranch.