A Vested Interest

Despite a tight budget, the team in Jamestown, R.I., steps up to deal with droughts and high wet-weather flows, earning praise for efficiency
A Vested Interest
David Green, assistant superintendent, opens a mud valve to supply flow to the 63,000-gallon secondary clarifier (Ovivo).

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A team of three does it all at the Jamestown (R.I.) Wastewater Treatment Facility, from dealing with I&I and droughts to operating on a limited budget.

Jamestown is a picturesque island community on Narragansett Bay with 5,400 year-round residents. The treatment plant, established in 1979, has always been in compliance, but now operates much more efficiently, thanks to its close-knit and dedicated crew, led by plant superintendent Doug Ouellette.

“When I became superintendent in 2000, we began operating the plant by the O&M manual as designed, and we reduced our electric bill by almost half,” Ouellette says. “We started matching the number of process units online to the amount of influent, whereas before, we sometimes had more units online than we needed.”

A process equipment upgrade in 2007 helped make the plant even more energy efficient. “We upgraded the aerators, waste pumps, blowers and process unit that operates the clarifiers,” says Ouellette. “From 2004 to 2007, we lined more than 18,000 feet of collection system pipe and replaced 6,000 feet with new PVC. We also replaced more than two-thirds of the manholes. But it’s not done yet. Money is tight.”

Still, he and the team persevere. The facility has won several awards, including the Most Efficient Secondary Treatment Facility award from the Narragansett Water Pollution Control Association (NWPCA) in 2009 and 2012. “We all live in town and are part of the community, so we have a vested interest in how the plant is run, and we take pride in it,” says Ouellette. “We just want to do a good job.”

Small plant, big results

The plant’s effluent is outstanding. In 2012, BOD removal efficiency averaged 98 percent, and TSS removal 97.6 percent. Treatment consists of coarse screening, a grit chamber, fine screening, extended aeration, clarification and chlorination. Biosolids are sent to contractor Waste Water Services for incineration.

Equipment includes secondary clarifiers (Ovivo), waste pumps (Penn Valley), RAS and pump station pumps (Flygt — a Xylem Brand), aerator drives (Infilco Degremont), Olympian plant and pump station generator sets (Caterpillar), septage/sludge pumps (Hayward Gordon) and chlorine system pumps (LMI Milton Roy).

The collection system upgrade ending in 2007 was long overdue. “It was built in the late 1800s of vitrified clay, with 2 foot sections and a lot of joints,” says Ouellette. “The upgrade has reduced our I&I and the number of blockages we get, and it just keeps the collection system running better.”

In the mid-1990s, the plant began recycling treated effluent to the town’s golf course. “The town got a $1 million grant to build a retaining pond on the course, and we pump the effluent half a mile via high-density polyethylene piping,” says Ouellette. “The effluent waters the entire course and flushes the toilets in the bathroom at the fifth hole.”

In 2007, the plant installed a multiple-disk membrane filter (Aqua-Aerobic Systems) to help meet its reclaim requirements for the golf course. The filter polishes about 300,000 gpd of secondary effluent. This effluent is pumped from the final contact tank to the filter, then flows by gravity to the golf course. The rest of the secondary effluent flows out of the contact tank to the outfall in Narragansett Bay.

Meeting challenges

Ouellette, a Grade 3 operator, started with the plant in 1989, and Dave Greene, also Grade 3, joined him in 1992. When Ouellette was promoted to superintendent, Greene was promoted to assistant superintendent. Paul Robertson, Grade 2, joined the team as an operator in 2004.

“You have no idea what you’re in for when you take this job,” says Ouellette. “It’s a baptism of fire. You can read the O&M manuals and learn how the plant is supposed to operate, vendors can teach you about the process in the classroom, but you really have to learn by doing.”

Robertson observes, “Our greatest challenge is I&I and an occasional drought. We either get too much water or not enough. The collection system upgrade has helped reduce I&I. We switched to bigger pumps, which helped stop sanitary sewer overflows caused by I&I. The pumps can handle the increased flow entering the collection system.”

During heavy rains, the team protects the biological process by isolating the aeration basins. “We have four 170,000-gallon basins, and we operate only the ones needed to handle current flows, which is typically two,” says Ouellette. “When we see a rain event on the horizon, we plan accordingly by monitoring the flows. When the slug of I&I starts to affect the facility, we isolate the basins with the mixed liquor in them, and open the empty basins. This prevents a washout and loss of biomass.”

Robertson adds, “The facility operates like a primary plant for awhile. When the rain stops and the flow slows down, we open the isolated aerators with the biomass intact, and the plant snaps right back.”

Several years ago, the plant experienced a drought for most of the summer. “The flow dropped below 200,000 gpd and we were operating with one aerator and one clarifier,” says Robertson. “We had to monitor our process, since we could have had too much detention time.”

The team was especially creative in resolving an issue with a chlorine alarm. “While pumping to the golf course, especially during low flow, the chlorine contact tank would pump down below the chlorine probe, setting off the low-chlorine alarm,” says Ouellette.

To solve the problem, the operators placed a sump pump in the contact tank about 4 feet below the effluent level. They took a recycling bin, drilled some drain holes and attached the bin to the tank’s catwalk. “The chlorine probe hangs in the bin, the pump delivers chlorinated effluent into the bin, and the effluent passes over the probe,” says Ouellette. “The drain holes allow the effluent to drain from the bin as the pump continues to pump new effluent in. This keeps the probe wet regardless of the tank level.”

Typical day

When not dealing with I&I or droughts, the operators’ days are routine. They work 7 a.m. to 3:30 p.m. and are on call after hours. They sample for BOD, TSS, coliform (MPN), total nitrogen, nitrite, nitrate, and oil and grease, and send the samples to an outside laboratory. They perform routine maintenance and, when time permits, take outside classes.

“We’re limited in local offerings, but the NWPCA and Atlantic States Rural Water and Wastewater Association offer classes,” says Ouellette. “In Rhode Island, we’re not required to get CEUs like on the water side.”

Influent quality doesn’t pose a huge challenge: “It’s all residential and boatyards, and they generally don’t dump bad stuff down the drain. The population doesn’t increase much in the summer, so we don’t have to deal with a population influx like they do on Block Island.”

Future improvements

Ouellette has a wish list for future upgrades that includes a SCADA system: “We like being hands on, though, since we want to make sure that what we intended to do got done. We’re kind of old fashioned that way.

“I would like to do more pipe lining and replacement if we can get the funds. I’d also like to expand our reuse program beyond the golf course, perhaps for the school’s ballfield or other areas in town where they could use the water.

“We’ve talked about putting solar panels on the south side of the plant if we can get a grant to fund it. We were looking at a wind generator, but the people on the island weren’t all that receptive.”

In the meantime, Ouellette and his team are content: “We have the support of the town as well as the Rhode Island Department of Environmental Management. We enjoy doing what we do. It’s a very positive thing for the community.”



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