A new drinking water plant opened beside the Kentucky River a few years ago, but its main customer, the city of Lexington, is about 30 miles away.

The plant helps Kentucky American Water meet the city’s water demand, now and for many years. The team at Kentucky River Station II at Hardin’s Landing received a 2017 Award of Excellence in Water Plant Operations from the Kentucky/Tennessee Section American Water Works Association.

Kentucky American Water operates the drinking water system in Lexington. A 31-mile, 42-inch pipe connects Lexington and its 322,000 people to the Hardin’s Landing plant. A 20-mile, 16-inch pipe connects the plant to the city of Owenton, about 16 miles north.

Sustaining flow

The 20 mgd (design) Hardin’s Landing facility supplements Lexington’s own drinking water plants: the River Station plant built in the 1950s and the Richmond Road plant built in the late 1890s. The new plant offers many advantages, according to Nathan Clark, senior superintendent of operations for the northern division of Kentucky American Water. One relates to how Kentucky River water is divvied up among users.

There are 14 locks on the river, all installed for navigation. Four are in use, and the others are sealed. In a dry summer weather when no water flows over the dams, the pools between the locks essentially become reservoirs. “That was a problem for Lexington because when water stops flowing, they’re stuck with a fixed amount of water that they can draw from that pool,” Clark says. That has led to water shortages.

Pools between the locks are numbered, starting with Pool 1 at Carrollton on the Ohio River. Lexington draws from Pool 9; the Hardin’s Landing plant is the only one that draws from Pool 3. “We still are allowed through the Public Service Commission to draw only a certain amount of water from the river, but the plant gives us the option of pulling an additional 20 million gallons if Lexington is drawing the most it can,” Clark says.

Another customer

In 2013, Kentucky American Water acquired the Owenton water system, serving 1,500 people. The company decommissioned the city’s water plant. Owenton is now served by the Hardin’s Landing facility and can draw water from Lexington if needed by way of the interconnection.

Kentucky American Water is now replacing distribution pipes in Owenton. Low pressure has been a problem because some customers on side streets long ago installed their own pipes. “Customers installed what they thought would handle the demand, but now it isn’t enough to provide for the people who moved into the area,” Clark says. “The issue now is that people want water, but it isn’t as easy as expected to give them water service.”

New pipes are being installed where the most people are and where growth is occurring. Because of the cost, it’s a long-term project.  

Capable team

Clark was not supervising the Hardin’s Landing plant when the team won the operations award. “We knew this was a good plant,” he says. “Our operators are all well-qualified and well-trained, so we knew what they do would stand up to anyone else.”

Team members are Jason Case, production supervisor; Bill Allen, David Pittman and Jerry McKenzie, Class IV operators; and Brennan Browning, Class III operator. This group communicates regularly with the team in Lexington to keep the water moving.

The process at Hardin’s Landing begins at an intake structure in the Kentucky River. Four pumps (two Weir Floway and two Flowserve) run based on demand: two 700 hp pumps with variable-frequency drives and two 500 hp pumps with fixed-speed drives.

Under typical daily demand of 7.5 mgd, just one of the 700 hp pumps is sufficient. If demand rises to 10 or 15 mgd, operators can use one of the 500 hp pumps and fine-tune the raw water flow with one of the pumps with VFDs. All that power is needed to lift the water up a 400-foot bluff through a 42-inch pipe to the plant.

Potassium permanganate is fed at the intake. At the head of the plant, the water goes through a rapid mixer where polyaluminum chloride is added. Four settling basins with paddle mixers build the floc. The paddle in each basin spins slower than the paddle in the previous basin. Then water flows through plate settlers.

Sludge is pumped to a settling basin on the front lawn of the plant site. Two belt presses (Alfa Laval Ashbrook Simon-Hartley) and a conveyor dewater the material, which is spread on land to dry. The water removed flows to a pair of clarifiers and is returned to the river.

Drinking water flows through standard mixed-media sand and anthracite filters. It then flows into a clearwell or, if the turbidity is too high, into the clarifiers and then back through the process. Chlorine, fluoride, orthophosphate and ammonia are added before distribution.

Adding flexibility

The Hardin’s Landing plant provides insurance against prolonged dry spells. In 2016, almost all Kentucky counties experienced drought. With its interconnections and potential for expansion, Hardin’s Landing will take some of the sting out of the next drought.

Getting to that stage required significant time and effort before the plant began operating in 2010. The approval process before the Public Service Commission lasted more than a year, and once the commission gave its approval, people in the path of the pipeline mounted a court challenge that was ultimately unsuccessful. Officials in Louisville, about 60 miles northwest of Lexington, proposed supplying water from the Ohio River, but the Public Service Commission rejected that option.

There were small glitches when the plant started up, but those were soon solved and the plant has been running smoothly. “Since this plant was put in service, it has given us the ability to do periodic maintenance on the plants in Lexington and to pursue other capital projects,” Clark says.

In the past, there were times when Lexington could not shut down because demand required that it keep operating. Now the region is better prepared for an unpredictable future.

Building down

In addition to awards for operations, the drinking water plant at Hardin’s Landing in Kentucky won an award for its design. It’s what you don’t see that matters. What you don’t see makes work easier on team members because they don’t have to go outside.

“If you were to pull up the parking lot, there are two floors belowground, below the offices,” says Nathan Clark, senior superintendent of operations for the northern division of Kentucky American Water. “Instead of making our footprint real wide, we tried to condense the overall footprint of the plant.”

It’s easier for operators to be in one building instead of walking around a campus. “We do have more steps to climb,” Clark observes.

Bad weather reveals other advantages of the design: “If it’s pouring rain and lightning takes out a pump, everything is right here in this one building. It’s just a matter of going down and verifying that the pump did shut down. Run back up a flight of steps to the control room and you can do your other checks.”

The Grand Honor Award for design came from the American Council of Engineering Cos. of Kentucky for 2013. The judges also cited the plant’s raw water intake, a sump installed to a depth of 80 feet with jet grouting to strengthen the surrounding soils.