Defying gravity: the art of getting water to flow uphill

Feb. 1—With every faucet we turn, shower we take, or toilet flushed, water miraculously appears from our pipes. But how it gets there is no small feat for water systems in the mountains.

The ebb and flow of water through Waynesville's pipes is a never ending cycle, and it doesn't happen by itself. A network of tanks and pump houses shuttles water from its source up the mountainsides to homes that can't be served by gravity.

All the water in Waynesville — the cleanest in North Carolina mind you — flows from the Allen's Creek reservoir, fed by the creeks and streams in the protected 8,000-acre watershed.

"The bulk of our customers are just on a gravity system, which means it just free flows from the water plant," said Jeff Stines, public services director of the Town of Waynesville. "The higher elevations are where we get into the pump houses and reservoirs."

Waynesville has a network of nine pump stations and 11 tanks to move water uphill. Most are on Eagle's Nest Mountain. The pump stations act like a series of stairsteps, moving water from one tank to the next.

"It works its way up the mountain, all the way to the very top," said Brandon Worley, pump technician for the Town of Waynesville public services. "We're having to push that water uphill so it will roll down the hill and that's where your pump stations come in."

Water passes through six pump stations en route to the very highest tank at Eagle's Nest.

"The pump houses are placed kind of strategically based on pressure. So you will place a pump house where you're starting to lose pressure. And that's where you'll grab that existing pressure and send it to a tank. And then there's a lot of other things involved in that with the engineering side," Stines said.

The water begins its climb up Eagle's Nest at 2,500 feet in elevation. The top of Eagles Nest is 5,500 feet — so the water gains nearly half a mile in elevation.

"You're pushing water 2,500 feet straight up," Worley said. "That's a long way up. That's why you have to do it in stages."

Water towers in flat places follow the same principle.

"Their tanks are high because they're wanting to achieve something we're achieving with a mountain, and that's elevation," Worley said.

But it's easier to pump water up a tower once than through a whole series of pumps.

The pumps are 75 horsepower pumps, with motors inside that sling the water out of slots — imagine a boosted gristmill — moving the water to Laurel Ridge then to High Ridge and upward, climbing the stairway of tanks until the top.

There are tanks along the way to serve homes at that elevation, to save the cost and energy of pumping more water uphill than needed.

"It wouldn't be feasible to do one tank at the top that feeds everybody," Stines said.

Each pump station water passes through adds an expense — from the maintenance of equipment to cost of electricity to power the pump. Residents served by the pump-and-tank network pay more for their water.

"If someone live at the top of Eagle's Nest you will pay 'x' additional dollars each time it goes through a pump," Stines said.

But what signals the uphill motion?

The answer — the time of day. Every day from 11 p.m. to 6 a.m. is when water is pumped from the water plant to maintain water levels into the heartbeat, Big Cove.

"That's off peak hours, that's when we get the best rate for our electricity," Worley said. The per kilowatt cost of electricity is cheaper at night, when demand is less.

Also, it takes less electricity to pump water at night when the water lines aren't in active use and constantly losing pressure in the pipes.

Of course, the mobility of water can be unpredictable.

There are times like fires, when more water is used, or heavy rainfalls, when the water levels rapidly rise. In those instances a low level and high level alarm will alert someone at the water plant — where someone is on duty 24/7 — to inform public works about the situation and what tank to go to.

"It's all connected together. It's all one big giant spider web," Worley explained.

Worley can check these water levels via an iPad that displays the times and levels at the plant.

And thanks to the data system — supervisory control and data acquisition — or SCADA, the public works team can supervise water levels in the pump station and switch off the pumps when the water level reaches the maximum.

"You can see it in those tank levels. Even though it's a 100,000 gallon tank, you can still see it, because you're having to pump more," Stines explained. "Like Laurel Ridge may pump three and a half hours from the pump station. If the homeowner has a leak that they don't know about, our pump hours are going to jump from three and a half to four hours."

The best way to prevent big leaks, Worley said, is to winterize homes that are going to be vacant. In other words, shut off water at the street and house's main inlet.

If not, without the water flowing through the system from flushing and other mechanisms. The stagnant water is more likely to freeze and burst the pipes.

"People don't think that the temps could lead to a pipe burst and water coming out of the tank faster," Worley said. "It don't take long to drain 100,000 gallons."