At North Port, Nothing Is Wasted. The Clean-Water Plant Even Has a Garden Where Operators Grow Healthy Foods

An award-winning 7 mgd clean-water plant in North Port, Florida, epitomizes resource recovery by turning effluent and biosolids to beneficial uses.

At North Port, Nothing Is Wasted. The Clean-Water Plant Even Has a Garden Where Operators Grow Healthy Foods

Superintendent Marc Beauregard (right) has high praise for operators like Mark Garwood and the plant’s instrumentation and control team.

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Look up the word “efficient” and you’ll find it defined as “producing desired results without wasting materials, time or energy.”

That certainly describes the main wastewater treatment plant in North Port, Florida. This 7.0 mgd (design) plant recycles all of its biosolids and effluent as it serves this community of 75,000 in southern Sarasota County, just inland from Venice.

Biosolids are turned into Class AA compost for use in landscaping and gardening, some of it in the community’s Employee Garden. Effluent passes to a reclaim storage tank and then is recycled as irrigation water for area lawns, parks and golf courses, or is pumped into injection wells.

“A small portion, about 10,000 gpd, goes to a Tommy’s Car Wash in town,” says Marc Beauregard, wastewater superintendent. “That application recently won a David W. York Award for water recycling from the Florida Water Reuse Association.”

Nutrient removal

The North Port facility is the larger of two plants serving the community. The Southwest Water Reclamation Facility (2 mgd) is just a few miles away.

At North Port, wastewater enters through a headworks equipped with automatic bar screens (Parkson Corp.) Then it moves to a modified Ludzack-Ettinger process with eight basins containing two anoxic and six aeration zones, each 225,000 gallons capacity.

The process is designed to use the nitrate produced by the aeration zone as an oxygen source for bacteria breaking down the raw wastewater in the anoxic zones. The oxygen-depleted return flow then enables microorganisms to consume phosphorus. The basins are equipped with Turblex blowers and fine-bubble diffusers (EDI). Hoffman blowers serve as backups.

After biological nitrogen and phosphorus removal, the water settles in four circular clarifiers, then passes through four deep-bed sand filters (Severn Trent). Disinfection occurs in four contact basins using liquid sodium hypochlorite injected by peristaltic pumps (ProMinent).

The purified effluent flows to a 2.5 million-gallon recycled water storage tank, before being pumped to end users. BOD removal averages 99% and TSS removal 98%. Nitrogen is reduced to 6 mg/L and phosphorus to 2 mg/L.

Solids to compost

Biosolids are aerobically digested in four digesters with a combined 600,000-gallon capacity. The material is dewatered to 20% in a centrifuge (Hiller); Synagro trucks it to the company’s windrow composting operation. Monthly solids production is 45 to 50 dry tons — one or two truckloads per week.

The plant also accepts about 50,000 gallons a day of landfill leachate. It doesn’t harm plant operation and in fact improves it, says Beauregard: “It has a pH of 7 to 8. We add it to the digesters; it improves pH and helps with decanting the solids.”

A Wonderware SCADA system (AVEVA) provides the information and control operators need. Lucity provided the preventive maintenance package. Odors are well managed by a biological scrubber and carbon filter outside the headworks. 

Change for the better

The treatment plant dates back to 1960 and was modernized with a number of improvements in 2009. Still, when Beauregard arrived a few years later, there was more to do. He and Chad Nosbisch, water and wastewater operations manager, led a hardworking staff that made changes to bring the plant to the performance levels it is achieving today. The team includes James Bedford, chief operator, and operators Mark Garwood, Michael Stack, Ward Wright, Dakota Koontz and Nicholas Topolnycky.

“We came in with a new vision and put in a lot of blood, sweat and tears to make the plant what it is today,” Beauregard recalls. “Things basically needed sprucing up. There was equipment that hadn’t been replaced. In some areas, we needed to start all over again.”

The Turblex blowers made a big difference in how the plant’s aeration basins and aerobic digesters operate. In other areas, it was a matter of new paint and coatings. The SCADA system servers were upgraded, and new PLCs are scheduled to be added this year. The automated bar screens were new last year.

The biggest improvement came in the biosolids area. “We had two digesters and three mixing tanks,” Beauregard says. “We removed walls and converted the mixing tanks into one large storage tank. That gave us more daily solids capacity and a place to rotate our waste activated sludge, and it improved our ability to decant.” The upgrade also included two new digesters, and the addition of Hoffman blowers. 

Praise for the team

Beauregard takes his hat off to the operators, who are supported by an excellent instrumentation and control and field operations staff. They don’t rely solely on the city’s maintenance staff: “They do it themselves, be it picking up a paintbrush, shovel or wrench.

Bedford and Wright hold Class A licenses; the operators all hold Class C. “I have an exceptional staff,” Beauregard says. “After nearly 35 years in the business I don’t feel I’m here to supervise operators but to train future superintendents.”  

Finding new operators, along with adopting new technology and serving a growing community, remains the utility’s biggest challenges. The COVID pandemic, during which many people worked from home, made recruiting and hiring all the more challenging.  

Those same factors have made the application and certification processes slower than normal. “Operators are in demand everywhere,” Beauregard says. The slower hiring process can result in candidates taking jobs elsewhere, as open positions are abundant. 

Getting recognized

Still, Beauregard remains optimistic. “Nothing’s insurmountable,” he says. That attitude is no doubt one reason North Port has achieved first or second place four years running (first place for 2021) in the Florida WEA’s Earle B. Phelps Award competition. The honor recognizes plants for exceptional operations, maintenance, recordkeeping and effluent quality.

The judges were right on target about the effluent: It’s so clean the utility is seriously considering direct potable reuse, in which the effluent would go directly into the region’s potable water supply, after further treatment at the city’s water treatment facility.

An engineering firm is studying the science and the economic feasibility of the idea, but Beauregard is convinced it will work: “When we have public tours of the facility, I’ll offer to take a drink of our effluent. It is exceptional. There’s nothing in it I wouldn’t drink.”

Direct reuse would literally make the North Port treatment process a closed loop — extra efficient, you might say.  



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