
Farrell Owens shows one of the books of standard operating procedures that have been created for every area of the plant and every process.
If the operators at the Percy D. Miller Water Treatment Plant are experts at operating their systems, it’s because they wrote the standard operating procedures manuals themselves.
“We came up with the idea while talking about emergencies like the bird flu crisis,” says Farrell Owens, manager of the facility in Winchester, Virginia. “What would we do if we had 25% or 50% of our staff out? If we had good SOPs, could other people come in and do the work?
“So we went over every section of the plant — every building, every pump, every valve — and developed pictures, descriptions and procedures, by operators for operators. Plus, we rewrote the instructions so everybody could understand them.”
A new attitude
The original facility was built in 1957; it was upgraded in 2012. It is designed to process 10 mgd of water drawn from the North Fork Shenandoah River and deliver it to the distribution system. The plant uses conventional flocculation, sedimentation, filtration and disinfection stages. Fluoride is added to the finished water, as is AQUA MAG blended phosphate (Carus Corp.) for corrosion control.
The staff works 12-hour shifts, including one team member who floats and performs the lab work. Brian Broadstreet is chief operator; Wade Arnold, Zach Reinitz, Patric Cunningham and Brian Armel are lead operators; James Dowd and Brandon Linquist are operator trainees.
The 2012 upgrade made significant changes and coincides with the string of awards the plant has won from the Virginia Department of Health. A change in attitude helped make a difference, too. “We always knew we could make good water,” Owens says. “We got rid of the ‘that’s how we’ve always done it’ thing. The change in attitude helped a lot.” He credits Broadstreet for leading the effort.
Major improvements
A new chemical facility, an Automatrix SCADA system and a new two-meter belt press (Evoqua Water Technologies) were highlights of the plant improvements. Previously, sedimentation solids were placed in a lagoon and pumped out periodically.
“We paid a lot to have all that water hauled away,” Owens says. “We added the press, and now we pump solids from the settling basin to our gravity thickener and press them to 21% to 22% solids. Then we put them in a roll-off that a Maryland firm hauls away for us. It’s a lot less costly.”
At the same time, the plant team cleaned out and lined both lagoons with new plastic, changed its flocculators from horizontal to vertical, and replaced the old chain-and-scraper mechanism with new plastic components. “The horizontal flocculators required a penetration through a wall, with a very large sprocket attached to the smaller motor and gearbox,” Owens says. “We had constant leaks.”
With the vertical flocculators (Evoqua), there is no wall penetration and no sprocket, and operators can better adjust flocculator speed. The new plastic chain (also Evoqua) is lighter and uses a smaller motor and gearboxes.
The chemical feed system has changed, too. “We used to feed caustic soda to control pH,” Owens says. “But we’ve changed from ferric chloride for coagulation to polyaluminum chloride. Now, it’s rare to need a pH adjustment.”
The plant also added a new high-service pump station, equipped with 500 hp Flowserve pumps and a pair of 1.5 million-gallon storage tanks, increasing pumping and storage capacity and adding capability to expand with service area growth.
Excellent clarity
The filters (The Roberts Filter Group) have a mixed-media bed of sand, rock and anthracite coal. Backwashing typically occurs every 100 hours. “Since we started using polyaluminum chloride as our coagulant, we get 100 hours before backwashing every time,” Owens says. “Before, not only was ferric hard on the plant, but we’d get about 70 hours of filtration before backwashing, maybe 60 hours in winter.”
The treated water is chlorinated, then goes through the storage tanks for adequate contact time. Additional storage is provided by two ground tanks and one elevated tank. Total storage capacity is 7 million gallons.
The stored water is excellent quality. Turbidity is the critical measure, and the plant has an exceptional track record there. “We normally average 0.02 to 0.03 NTU,” Owens says. That’s despite wide variance in the turbidity of the source water, which usually runs about 10 NTU but can spike to 500 NTU if there’s rain in the nearby mountains.
“I’ve seen it get as high as 700 NTU,” Owens says. “But our plant is always capable of putting out good water, no matter what the river brings us.” The team constantly monitors turbidity using a Hach TU5300 meter. “We optimize the coagulant feed at the flash mix process before the water goes into the flocculators,” Owens says. “Ultimately, that will mean less work for the filters. That’s the key to low turbidity.”
The team does not have responsibility for the distribution system serving Winchester, a network that includes some of the first wooden pipes installed in the U.S. According to a video on the plant’s website, the pipes were fashioned out of 10-inch oak logs; a horse-driven boring machine made the holes down the centers.
Standardizing operations
While Owens and his team have figured out how to operate the plant efficiently and effectively, their jobs don’t end there. Owens makes a big point about the plant’s complete manual of SOPs, how they were developed and their reader-friendly style.
He made a presentation on the SOP program at the 2017 Virginia American Water Works Association meeting, stressing the need for operator involvement and plain language. “Sit down with key personnel and write out a list of all the components that make up your facility,” he says. “Don’t leave anything out, no matter how small it may seem. You can take things out later if needed.”
He also talked about the scope of the SOPS, starting at the beginning of the plant. “Start where the water enters the plant and follow the flow pattern all the way to the end,” he advises. “That keeps the project on track.”
At Winchester, that meant starting at the river dam and continuing to the river rake, the raw water pumping station, the flash mix operation, flocculators, sedimentation, sludge withdrawal, chain-and-flight mechanism, and chemical feed and disinfection, as well as instrumentation and controls.
Step by step
At each process step, Owens and his team made a list of items to include in each SOP. They include the equipment name, manufacturer, serial and model numbers; the purpose of the equipment; operating instructions; maintenance procedures; safety precautions; and contact information. The information is straightforward and understandable.
For example, a section about the dewatering system states: “It is very important to remember that there are a lot of moving parts on the belt press and to stay clear of these parts when in motion.” Then comes a series of clearly written steps:
- Step One: The operating station is a touch screen and will likely be off when you approach it. Simply touch the screen and the startup screen will appear.
- The Auto Cycle Status screen will appear and show “Ready” outlined in black toward the top middle of the screen, to the right of that in the top right corner.
- There is a blue box that reads “Belt Press Auto Mode.” This means that the press is in the auto mode and not in manual. To switch to manual, simply touch the blue box and it will turn yellow.
- Emergency procedures are also straightforward:
- In the event you need to stop the belt press in an emergency, simply pull on the emergency E-Stop red wire, which runs the length of the belt press on both sides, or hit the E-Stops, which are also located on both sides of the belt press.
- Returning back to the start is simply doing everything you just did, only in reverse.
The instructions are accompanied by clear graphics that show the equipment components and use arrows and captions to point out key features, including on and off buttons.
Language lesson
One of Owens’ presentation slides is titled “Watch Your Language, Young Man.” By this he means that instead of using the jargon and techno-talk that has grown up around the water and wastewater field, write in plain, understandable language. And call something by the same name throughout.
For example he points out that the blended phosphate used at the Winchester plant can be referred to as blended phosphate, PO4, AQUA MAG or corrosion inhibitor. Likewise, the plant’s disinfectant can be referred to as hypo, chlorine, bleach or disinfectant.
“Every facility has language that applies specifically to its environment, and this industry has language specific to the water and wastewater fields,” Owens says. “Every SOP should have language and details as if the person reading it has never worked in this field. Maybe they have never been to your facility. They may not even be interested in doing the work.
“In emergencies, you might be using existing personnel from other departments. You should stick to the most common name in the plant, preferably what it is on the SCADA screens or paperwork.”
As in all water utilities, Owens and the Winchester team are always on the lookout for new employees. “We advertise with the city,” Owens says. But finding and training employees are two different sides of the street. That’s where the SOPs come in handy, written by operators, from one end of the plant to the other.
“They’re just about the best training tool we have,” Owens says. Process improvements, a change in attitude and clear SOPs written by staff members — it’s a winning combination.
Finally, the top
The Gold Award from the Virginia Department of Health culminated a long climb toward perfection at the Percy D. Miller Water Treatment Plant.
“For 12 years, we’d been waiting for this,” says Farrell Owens, facility manager. “We won the Silver Award seven times and the Bronze Award twice since 2007. We were always capable of producing good water.”
Indeed. According to the award recognition, the plant met strict standards for turbidity at least 95% of the time in tests taken at 15-minute intervals at all hours of the day during a one-year period. The plant’s average turbidity is in the range of 0.02 to 0.03 NTU, from surface water that averages about 100 NTU and that can reach several hundred NTU in rainy weather.
“Our goal every day is to provide our customers with the best and safest drinking water possible,” says Perry Eisenach, director of Winchester Public Services. “We were very proud to receive the award, as it is recognition of the water treatment plant team’s hard work, dedication to detail and excellent customer service.”
The award is administered by Health Department’s Office of Drinking Water. The program’s performance goals for water clarity and filtration were developed using studies and research by the U.S. EPA, the American Water Works Association and the waterworks industry.