Achieving Phase IV in the Partnership for Safe Water Program - Treatment Optimization Program means more than peer recognition at the Crown Water Filtration Plant in Westlake, Ohio.

It’s the guidebook for process improvements, and it serves as an ideal training template for new operators joining the plant team.

“With retirements and new people coming on board, Phase IV is an excellent way to explain the operation of the plant to new operators,” says Mark Petrie, plant manager. “It helps them get a better understanding of our operation.”

The Crown plant achieved Phase III Directors Award status in the Partnership program in 2004 and has maintained that distinction for 11 years. Now the Phase IV award has recognized the plant’s continuing efforts to optimize its treatment processes, including chlorination, automation and turbidity control, while meeting and surpassing all federal standards for water quality. It’s just the 15th water treatment plant in the nation to achieve the Phase IV status.

The Crown plant, owned by Cleveland Water, is one of four large water treatment plants serving metropolitan Cleveland. It provides water to about one-fourth of the metro area’s 1.3 million people. Commissioned in 1958, the plant treats an average of 41.5 mgd, drawing from Lake Erie through a crib 2.5 miles offshore.

An 8-foot main brings the lake water by gravity to the raw water well, where vertical pumps (Peerless and Layne/Verti-Line) lift it to two 54-inch mains that feed the plant. Under normal demand, only one main is in use, but when demand rises above 60 mgd, both mains operate. The plant capacity is 130 mgd.

Conventional process

Treatment begins with addition of potassium permanganate and later powdered activated carbon to the raw water mains upstream of the rapid mixers and coagulant. Two raw water basket screens (Evoqua) remove large debris before the water passes through inline rapid mixers in the north and south raw mains. The plant uses alum blended with 5 percent polymer (USALCO, LLC) as a flocculant.

The plant is designed with 25 multistage flocculators; tube settlers are positioned near the top of each of the 10 sedimentation basins. Settled water flows to a dozen 72-inch-deep, anthracite-filled mono-media filters equipped with Leopold - a Xylem Brand underdrains. Sodium hypochlorite provides disinfection, and orthophosphate is added for corrosion control.

The plant also feeds fluoride into the process water. Finished water is stored in a 36.5-million-gallon inground reservoir before distribution to customers through a 650-mile piping network that consists of four zones. “We pump directly to two of the zones,” says Maggie Rodgers, plant operations manager. “Secondary pump stations supply the remaining two zones.”

Two Perrin plate presses (Evoqua) dewater the residuals to a dry cake distributed to farmers who value the lime content, which is added to aid in press plate operation. Petrie says the plant is studying alternative residuals management options.

The existing control system was upgraded to Allen Bradley ControlLogix (Rockwell Automation) during a $10 million plant renovation project from 2010 to 2013. The Hach Water Information Management Solution and Laboratory Informational Management System are used daily for plant operations and Partnership IV requirements.

Substantial renovation

The Phase IV designation recognizes plant programs to improve and optimize operations. At the Crown plant, the renovation included upgrades to disinfection and filtration. “In 2013, we switched from gaseous chlorine to sodium hypochlorite at 6.5 percent solution,” says Petrie. “It costs a bit more but improves the safety of our operations and makes us a better neighbor.”

The plant also installed a water softening system to reduce the sodium hypochlorite concentration to 6.5 percent from the 12 percent delivered by semi-tanker. That also reduced the mineral content of the solution and helped prevent scaling in the pipe delivery system.

As with any surface water, turbidity is often an issue, and a major target of the optimization program. The Crown plant has optimized pretreatment to enhance filter performance.

For one thing, the plant now uses Hach Solitax monitoring equipment in each sedimentation basin to monitor turbidity. Petrie says that since the automation, operators no longer need to take grab samples every four hours. “We monitor turbidity in the basins, with the goal of keeping turbidity down so we can optimize our filter operation,” he says. “We have found the most efficient filtering rate to be 5 to 7 mgd per filter.”

Raw water turbidity normally runs between 10 and 20 NTU; it averages 0.40 NTU in the sedimentation basins. The plant team aims to keep filter influent at about 0.30 NTU. “Our operators are instructed to implement the filter-to-waste sequence if turbidity is above 0.09 NTU at filter effluent,” says Petrie. “Normally, we record turbidities of 0.02 to 0.03 NTU at the filter effluent, and our combined filter effluent at 0.03 to 0.05 NTU entering the reservoir.”

Pretreatment enhancement using Partnership IV guidelines also reduces filter-to-waste occurrences. The new SCADA instrumentation automatically monitors produced water turbidity and returns the filtered water to the head of the plant if the NTU standards aren’t being met.

Spikes in raw turbidity can occur, especially during stormy weather. “During Hurricane Sandy, which hit the East Coast but created high winds and rain across the Midwest, we saw turbidities as high as 370 NTU,” says Petrie. Despite that, the plant stayed within Partnership guidelines.

To keep the filters operating at peak efficiency, the Crown plant maintains a 0.20 mg/L chlorine dosage at the filter effluent. “We’ve been using hypochlorite for a couple of years — just enough to keep our filters where they should be,” says Petrie. The main plant chlorination occurs to the filter effluent water before it enters the reservoir.

In control

Turbidity is just one of the many operating parameters monitored and analyzed by the plant’s new data systems. The upgrade gives the staff instant snapshots of a range of parameters, helping them analyze and control water quality more precisely and easily than in the old days. “Plant optimization is the key to producing high-quality safe drinking water,” states Petrie.

The WIMS provides a complete picture of the water treatment, including secure data collection, reporting, user-defined alerts, and charting, graphing and mapping tools. It also interfaces with the SCADA and LIMS. While tying all the new systems together, the Crown management team, along with Paul Simundza, chief system analyst, incorporated new operational procedures and safeguards.

“The Partnership for Safe Water’s Level IV calls for optimized data collection and analysis,” says Franco Noce, assistant plant manager. “With our new systems, we’re able to compile a complete data history that can be analyzed every month. It’s a good system, and it has helped us in our work.”

Petrie adds that hands-on control is also vital as a backup: “It’s great to have SCADA, but it’s important that our operators understand how to do the math and feed the correct amount of chemicals manually. We need to understand both methods.”

Team approach

Entrusted with millions of dollars’ worth of resources and responsible for supplying high-quality drinking water and adequate fire flow for more than 300,000 people in 15 communities, the Crown plant staff works as a team. In a union operation, the crew works closely toward common goals. “Communications are vital, and management is hands-on as we all work together to solve problems,” Petrie says.

Muhammad Hague, assistant plant manager, stresses the importance of daily staff meetings and the use of a Microsoft SharePoint system to log data digitally on all shifts, including nights and weekends. “All of us have access: managers, analysts, laborers, the maintenance crew,” he says. “If issues arise, we address them immediately.”

With the assistance of Scott Naelitz, assistant plant manager, cross-training with an emphasis on safety has been instrumental in facilitating the cooperation and understanding. “They’ve enabled us to overcome any interdepartmental barriers and work hand in hand,” says Petrie.

While the Crown plant team is deservedly proud of the Level IV status in the Partnership for Safe Water, the true test of the facility and its staff is in the quality of the water it produces.

As Petrie puts it, “We don’t put water into our reservoir that we wouldn’t drink ourselves.”

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Lake Erie water

As a raw water source, Lake Erie has received a fair bit of attention because of toxic algae blooms in the far west end, attributed to agricultural runoff. Cities like Toledo have had to take special precautions to guard against algae-based toxicity in their drinking water systems.

Cleveland, however, draws its water from the central basin of the lake. According to Maggie Rodgers, operations manager of the Crown Water Filtration Plant, that section of the lake is deeper and has not experienced toxic algae.

The plant adds powdered activated carbon and permanganate for taste and odor control. “We produce good-tasting, safe water,” Rodgers says. “Even in winter, we keep adding PAC and permanganate. We want to produce the best water around.” Besides Rodgers, the team at the Crown plant includes:

• Mark Petrie, plant manager
• Muhammad Hague, Scott Naelitz and Franco Noce, assistant plant managers
• Victor Ervin, Bernard Branner, Mark Mittelstaedt and Darby Svoboda, water plant operator II; Jason Laboda, George Dunne, Adrian Lamb, Ernest Lee, Ralph Pasterak, Richard Readinger and Kimberly Smith, water plant operator I
• Fidel Rodriguez, machinist unit leader; Shirleter Bryant, Gene Greenawalt, Michael Pearcy and Stephen Woyma, machinists; Frederick Anderson, machinist helper
• Ken Criss and Richelle Gmys, electricians
• David DiMauro, labor foreman; Donald Gates and Emerson Young, laborers
• Jonathon Sedely, senior chemist
• Paul Simundza, chief system analyst
• Mary Bangert, store keeper