Please excuse the staff at the Palm Coast Wastewater Treatment Plant No. 1 for complaining about lousy weather.

Hurricane Irma was just the latest in a series of storms and wet-weather events that have kept them busy managing high flows in the plant and collections system. “In my 36 years in the profession, it seems like this has been one of the most unusual as far as rainfall is concerned,” observes Danny Ashburn, manager of wastewater operations. “It started raining in July. On top of that, we got a hurricane and then two nor’easters that funneled rain on us for 36 hours.”

The 15 inches of rain on already saturated ground doubled the plant flow and made it challenging to keep the system operating. “It affected us pretty heavily,” Ashburn says. “The longer it goes on, the more susceptible we are to failures.”

But Ashburn, chief operator Pat Henderson, lead operator Marco Pubill and their team have been up to the task. The 6.8 mgd (design) plant has maintained compliance despite the weather. It received a 2016 Plant Operations Excellence Award from the Florida Department of Environmental Protection and Florida Rural Water Association.

Advanced treatment

The plant serves 82,000 residents plus commercial accounts in Palm Coast, which stretches for several miles between St. Augustine and Daytona Beach. Built in 1972 and expanded four times since, the facility uses biological nutrient removal and advanced filtration to achieve a high-quality effluent that is mostly reused for irrigation and groundwater recharge.

From the influent wet well, raw wastewater passes through a pair of vertical mechanical bar screens (Parkson) and then to a grit removal system that consists of a cyclone section and a screw compactor section (Waste Tech). Three 15-foot-deep racetrack oxidation ditches follow, measuring 125 by 55 feet, with surface aerators and mixers.

The ditches, two supplied by Lakeside Equipment and one from Kruger USA, provide biological treatment including nitrification and operate in a phased single-ditch mode of the BIO-DENITRO process (Veolia Water North America). Team members monitor dissolved oxygen as the main operating parameter and plug the data into the plant’s SCADA system, supplied by Kruger USA with Square D control centers (Schneider Electric) and programmable logic controllers.

Treated water settles in six 65-foot-diameter clarifiers (Ovivo USA). Four Hydrotech Discfilters (Kruger USA) polish the effluent before it is chlorinated with liquid sodium hypochlorite and dechlorinated with liquid sodium bisulfite. Filtered water, meeting a reuse quality standard of less than 5 mg/L total solids, is pumped to a 6-million-gallon storage tank before reuse or discharge to the Intracoastal Waterway, about three miles away.

Biosolids are aerobically digested, thickened, dewatered in centrifuges (Andritz Separation), and stored in a dump trailer. A private hauler takes about five loads per week, at 18-percent solids, to a local composting site.

Henderson notes that to meet future treatment needs and to serve the far north end of the community, Palm Coast is constructing a second 5 mgd plant. “The new plant will take care of the growth of the community for at least the next five years,” he says. The community stretches a long way from north to south, and the new plant will take pressure off collections system pumps, which now must move water long distances.

Recycling and reuse

For decades, the state of Florida drained land areas and pumped water to the ocean. Today, however, the state practices water reuse to replenish the aquifer and extend potable water supplies. Palm Coast is doing its part.

“Most of the year, we supply treated effluent to area golf courses, highway median strips, and about 400 homeowners for spray irrigation,” Ashburn says. “We also sell recycled water to Hammock Dunes, an oceanfront resort development, which doesn’t have enough irrigation water to supply its golf courses and residential community.”

The Palm Coast reuse system dates from the installation of the plant’s filtration system in 2006 and reuse pumping facilities in 2008. The pumping stations keep the water constantly pressurized; usage is based on demand. Excess water is recycled to the groundwater through rapid infiltration basins in sandy areas around the community. During summer, essentially all effluent is reused for irrigation. In winter, more water is pumped to the infiltration basins. When they are fully charged, the excess is discharged to the Waterway.

Shared duties

The plant operators have diverse skills. “We don’t have a separate maintenance department,” Henderson says. That means the plant’s 10 operators fill both operational and maintenance roles. One staff member is assigned to enforcement of the utility’s FOG ordinance and works outside the plant inspecting grease traps.

In addition to Ashburn, Henderson, and Pubill, the team includes operators Tipo Toomalatai, Eric Stodola, Keith Jones, and Robin Cathey; operator trainees Chris DeBattista, Chris Sleep, John Bryl, and Dan Niemann; and Pat Garrett, pretreatment inspector.

“Our staff is critical for cleaning and maintaining the equipment,” Henderson says. “They take care of all mechanical repairs and all maintenance activities, in addition to operating the plant and making sure everything is running correctly.”

Safety is paramount. “We provide our operators with all equipment necessary to do the job safely,” Henderson says. Safety meetings are held at the plant twice a month. Operators also take part in the city’s safe driving program.

It’s working. In 2016, the plant recorded zero lost-time accidents; it received a 2017 Safety Award from the Florida Water Environment Association for Class B facilities. “We’re proud of our excellent safety record,” Ashburn says. “It ultimately benefits our overall operation to give the best service possible to our citizens.”

Emergency response

The Palm Coast staff also deserves praise for storm-proofing the wastewater operation.

As hurricanes and rainstorms pass through, the plant’s flow can double, the collections system can become overwhelmed, and pipes can break. “We get some solids loss, but it’s mainly a hydrological event, and the plant can handle it pretty well,” Henderson says. “We also get a lot of sand in the influent.”

The community has a number of on-site tanks that serve individual homes. The utility owns the tanks, which act like septic systems but discharge to the plant, adding to the overflows during storms.

Preparation is the key. Palm Coast maintains standing contracts with a number of vacuum truck firms. They can be called in during storms to relieve pressure on pump stations and overflowing manholes. “It’s also important to have your emergency generators ready to go and get them out into the field as quickly as possible,” Henderson says.

The plant has hurricane shutters for all windows. Team members keep loose equipment tied down and all electrical systems and pump stations in good shape. In anticipation of bad weather, vehicles are kept fully fueled and chemicals topped off. “That way, when events come through, we don’t have failures that hinder operations,” Henderson says.

Battling Irma

Hurricane Irma, which raced through the Florida peninsula in late August and early September, is a case in point. Palm Coast was hit by winds at 75 to 90 mph and more than 10 inches of rain in two days. About 80 percent of the electric utility customers lost power, including all 156 Palm Coast lift stations.

While the treatment plant itself is built on higher ground and did not flood, the heavy rains and flooding elsewhere produced flows from 10 to 12 mgd, as well as flooding in the collections system. Using an emergency plan it has had in place since the 1990s, the Palm Coast team made it through.

“We usually know about these storms before they hit us,” Henderson says. “We have a protocol we go through. Our systems have been able to recover once they pass.” The hurricane protocol is detailed and assigns roles to all staff members.

“Prestorm, we get a minimum of two volunteers to stay with the plant from the beginning (sustained winds of at least 35 mph) through the duration of the event,” Henderson says. “The A and B shifts for the poststorm period are scheduled with the rally point being the treatment plant. When the storm hits, the operators on duty monitor the SCADA system and, if possible, make corrections to the operation.

“The key is that employees not put themselves in a situation where they can get hurt. They should just monitor and keep track of repairs that will need to be made once the all-clear is given by the emergency management team.” Once that happens, calls are placed to all employees letting them know that A shift is starting (12 hours) and B shift should be ready in 12 hours.

“Operators who were on duty during the storm are placed on B shift and relieved from duty and are able to go home and assess their own damage,” Henderson says. After the storm, the A shift evaluates the plant and begins making repairs and cleaning up debris. If not all personnel are needed, the extra staff members are assigned to the collections system to help with tank truck pumping, work orders, cleanup or any other needed function.

By this time, all wastewater employees are working 12-hour shifts and continue to do so until all systems are back to normal. “We have a good action plan,” Henderson says. “Everyone knows what to do. It’s better to be prepared than sorry.”

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Stretching for safety

While most treatment plant operators might head for the coffee pot first thing in the morning, the routine is a little different at Palm Coast. The first shift spends at least 15 minutes in the lunchroom in group Exercise, stretching out the muscles while mentally focusing on safety.

“Every morning, we stretch together,” says Marco Pubill, lead operator. The staff began the routine about a year ago, starting with training sessions led by an expert from a local gym. The stretching exercises correlate well with safety: “By stretching your body, you help eliminate back injuries,” Pubill says. “It’s a safety-minded start to every day.”

Pat Henderson, chief operator, adds, “It’s a primer. It gets your mind set to do your work properly and safely.”