This North Carolina Clean-Water Plant Operates in Keeping with Its Sharp Appearance

Beauty runs more than skin deep at the Rockfish Creek Water Reclamation Facility as meticulous housekeeping pairs up with excellent maintenance.

This North Carolina Clean-Water Plant Operates in Keeping with Its Sharp Appearance

Operator C.J. Hyatt uses the touch screen for the Rockfish Creek Water Reclamation Facility’s 500 hp aeration blower (Atlas Copco).

In this case appearances are not deceiving.

The Rockfish Creek Water Reclamation Facility looks sharp, from the landscaping outside to the walls, floors, pumps, motors and blowers inside.

The facility, in Fayetteville, North Carolina, operates in keeping with its appearance. The 10-member operations team and a centralized maintenance group keep effluent in compliance and all equipment running smoothly. Leading the operations side are Scott McCoy, facilities operations supervisor, and Chuck Baxley, water reclamation facilities treatment manager.

Housekeeping is part of each operator’s regular role. “Our guys are assigned areas of the facility that they have to maintain,” Baxley says. “That includes painting, sweeping and clearing out cobwebs; wiping down blowers, pumps and motors; and making sure the filters are kept clean.”

A landscaping crew takes care of the exterior. “Our grounds are just nice,” Baxley says. “We take a lot of pride in it. We also keep our exposed gate operators, motors, piping and other items painted.”

Proud tradition

Rockfish Creek is one of two water reclamation facilities (Cross Creek is the other) owned by the Fayetteville Public Work Commission, a century-old water utility and electric company. The drinking water side includes the P.O. Hoffer and Glenville Lake water treatment facilities with a combined 58 mgd capacity and 23.5 mgd average demand. The maintenance group takes care of all four plants and more than 80 wastewater lift stations.

Both water reclamation facilities use activated sludge processes. The main difference is that Rockfish Creek (21 mgd design, 17.2 mgd average) uses aerobic biosolids digestion while Cross Creek (25 mgd design, 15 mgd average) has anaerobic digesters. Class B liquid biosolids from both are applied to some 4,000 permitted acres of cropland, including a 750-acre farm that the commission owns and operates.

“We actually farm the land,” Baxley says. “We plant corn, soybeans, sorghum and hay. Ours is one of the largest liquid land application programs in the state, and having our own farm is very unique.”

Tertiary treatment

The Rockfish Creek facility receives flow through gravity lines and a force main. Archimedes-type influent screw pumps lift the influent to the headworks, which includes an automated quarter-inch bar screen (WesTech Engineering) and stirred vortex grit chambers (Smith & Loveless).

After grit removal, the flow moves to five aeration basins by way of a weir-controlled distribution box, where magnesium hydroxide is added for alkalinity to sustain the nitrification process. “Years ago, we used lime,” Baxley says. “We’re just providing the proper environment for our microorganisms to remove the ammonia in the water.”

In the basins, six blowers (Atlas Copco) supply oxygen and provide mixing via fine-bubble diffusers (Sanitaire, a Xylem brand). Dissolved oxygen in the basins is monitored in real time with supplemental daily manual checks by the operations team.

The secondary-treated water passes to three 140-foot-diameter secondary clarifiers (two Envirex, one Ovivo). A chlorine diffuser provides disinfection as the clarified water overflows the weirs. “It gives us more detention time, and it also controls the algae that typically wants to grow on the weirs and the concrete launder structure,” Baxley says.

Traveling bridge sand filters (Aqua-Aerobic Systems) provide tertiary treatment. Sodium hypochlorite provides final disinfection, followed by dechlorination with sodium bisulfite before discharge down aeration steps to the Cape Fear River. Some of the effluent is used as seal water for pumps, for washdown and for other in-plant purposes.

Waste activated sludge is sent to five aerobic digesters supplied with oxygen by five Gardner Denver blowers. The pH in the digesters and in all storage tanks is monitored in real time. The digested material goes through gravity belt thickeners (Ashbrook Simon-Hartley) to achieve 3.5% to 4% solids for land application.

A contractor delivers and applies the material and handles site permitting and reporting. “Our staff does the incorporating after land application,” Baxley says. “We also do anything else the farmers need — liming, potash or whatever.”

 Keeping it running

The central maintenance staff is always available to the operations team. A computerized asset management program (Oracle) helps track tasks scheduled according to manufacturers’ planned maintenance recommendations. “Whenever we’re requesting work, we submit a work order to the maintenance group,” Baxley says. “The work is then assigned to a technician. Whether it’s a mechanical task or an instrumentation, electronics and control task, the proper person will go to the facility or lift station and perform that work.

“For our large equipment, like our aeration blowers, we have service agreements in place with a contractor who comes in to do the annual maintenance,” Baxley says. “We have hundreds of pumps and motors between the plants, and most of that preventive work we do in-house.”

Among their proudest accomplishments, Baxley and McCoy cite an apprenticeship program launched in the late 1990s in conjunction with the state Department of Labor. Baxley recalls, “The goal was to get every operator to Grade 4 certification and to land application certification if they so chose. There were monetary gains for those who completed the program.

“When it was all said and done, all of our operators were Grade 4. Right now, we don’t have that just because of turnover due to retirement. If you go back to five years ago, I was one of the younger guys, and I have 29 years. We’ve had a rash of retirements, and so we have some younger staff. We’re pushing those people through regional schools to get them eligible to continue with their certifications, but we’re no longer doing anything as structured as the apprenticeship program.”

Besides Baxley and McCoy, the Rockfish Creek team includes Thomas Urbanek, facility maintenance coordinator; Charles Autry, senior treatment plant operator; and Jeff Corder, Norman Johnson, Drew Scruggins, Darrick Hunt, Adrian Furr, Shawn Clark and C.J. Hyatt, treatment plant operators. 

Stepping up

Experienced or not, team members have proven their willingness to pitch in during emergencies. Among the biggest recent challenges were Hurricane Matthew in 2016 and Hurricane Florence in 2018. “We were just slammed at the facilities with really high flows and the corresponding high receiving stream levels,” Baxley recalls.

“The river was flooded, so our outfall was completely submerged. We had issues getting flow out of the plant. It was like having the flood gates open on one end, and then a roadblock on the other end. We just weren’t able to get the flow out as quickly as normal. All of our basins were at the tippy-top. That was pretty stressful. We were here for a week plus at a time. Our guys gave us everything they had.”

During the storms, the water reclamation facilities ran on 2 MW emergency diesel generators. A Detroit Diesel unit serves the Cross Creek plant; as of last spring, Rockfish Creek had a rental unit (Power Secure) while awaiting a replacement for its fixed generator.

Baxley noted that the water reclamation facility operations are electricity intensive. The staff has looked at options to reduce cost, including biogas-fueled combined heat and power at Cross Creek, but the projected payback was not acceptable. Some savings have come from a coincident peak rate that reflects the power supply costs from Duke Energy Progress, the power supplier for the commission.

Expansion ahead

The future holds challenges for the Rockfish Creek facility: “We are beginning the design of an expansion that’s going to take us to 28 mgd design capacity,” Baxley says. “Hydraulically we have reached 80% of capacity, at which point we’re required to be in the design phase, and we’re getting close to the 90% level where we would have to be under construction.

“Beyond that, I really feel like the next time we expand, or at our next permit cycle, we’re going to end up with nutrient limits. I foresee that happening in the next five years at both facilities. That is going to be a challenge.” It likely means creating zones within the aeration basins and adding more chemical treatment.

Meanwhile, staffing challenges continue. As openings occur at the treatment facilities, the commission places job listings on the North Carolina Rural Water Association websites and puts the word out to leaders of other area treatment facilities and to the North Carolina Eastern Region Operators Association.

“We advertise internally as well,” Baxley says. “We try to give folks an opportunity who are in other areas of our organization if they’re interested in this type of work. Our goal is to find somebody who has some experience, has certifications in their pocket and can hit the ground running. But that doesn’t always work out.”

In that event, good candidates include those who have taken technical school or college courses in related fields or who have field experience in water system or collection system construction or maintenance.

Operations supervisor McCoy is pleased with the team members, both veterans and newcomers. “We have a lot of new folks due to retirements and aging out,” he says. “I’m proud of the guys we have coming in. They’ve taken the initiative pursue all their certifications. They are motivated, and I’m proud of what they do on a day-in, day-out basis.”   



Discussion

Comments on this site are submitted by users and are not endorsed by nor do they reflect the views or opinions of COLE Publishing, Inc. Comments are moderated before being posted.