Conservation is the battle cry in municipal water departments across the country as more and more people begin to understand how important clean water is to everyone in the community. This truth becomes apparent most often when water service is interrupted. Add to that the real possibility of drought conditions and water table shift changing the free-flowing nature of the water supply, and suddenly everyone is concerned, and rightly so, about wasting this important resource.

How bad is it? Many municipalities around the country have chosen to stop conducting their longstanding flushing programs, as they have seen their water sources become less dependable. By eliminating the waste of water in the flushing process, the hope is, they will not have a shortage and need to restrict customer usage. Unfortunately, this plan is flawed by its very nature: By eliminating regular flushing of mains, the quality of the water becomes less reliable as deposits and bio-contamination grow unchecked.

"Most municipalities have decided to stop flushing because the lack of supply, and cost of the water supply," says Chris Wilkinson, president and founder of NO-DES, Inc. "The utilities must provide safe drinking water at the lowest possible cost, and as environmental stewards, the message we send our customers must be clear and concise: We'll never have enough water to waste."

The NO-DES System offers a range of solutions to many municipal water challenges, designed into one system mounted on a truck or trailer. By using the NO-DES Zero-Discharge Flushing System to conduct the water-main maintenance that should happen on a regularly scheduled basis, a municipal water utility can solve many of its problems at once, and even extend the time between required maintenance. And as you'll see, the NO-DES Zero-Discharge Flushing System dramatically reduces water waste.

NO-DES Turns the System Around

How does it work? The NO-DES System uses a pump system connected to hydrants to circulate the water through the mains in the opposite direction than they usually flow. This helps to loosen any mineral or biological deposits that have built up since the last time they were flushed.

Because the NO-DES system reuses the water in the mains for zero-discharge flushing, rather than releasing it from the hydrant, the water is circulated through the mains repeatedly, passing through the filtration system. As the main is flushed, the water's turbidity is monitored, and the zero-discharge flushing continues until the desired standard is achieved.

Out with the Bad

Why is zero-discharge flushing important? Flushing a water-delivery distribution system cleans water mains by creating high flows of water, which helps to scour deposits from the main, allowing clean water to flow freely. "The mains need to be cleaned to eliminate biofilm, improve water quality, eliminate free ammonia, chlorinate systems, eliminate nitrification problems, and improve residuals," says Wilkinson. "If you cut the flushing program, customers get a buildup of dirty water coming out of their faucets."

Water managers don't want poor quality water to get delivered to the customer, but eliminating the flushing program increases the likelihood of this happening. Even worse, the most complaints the water utilities receive is when this conventional flushing is happening, since this process is likely to dislodge pieces of a water main occlusion, and customers see discoloration in their tap and lavatory water as a result.

Reducing Water Waste with NO-DES

The conventional method of opening a hydrant to flush the mains can result in the loss of around 22,500 gallons of water for each hydrant opened: 1,500 gallons per minute for 15 minutes. By contrast, the NO-DES Zero-Discharge Flushing System only loses a couple of hundred gallons held in the hoses that connect it to the hydrants. Perhaps best of all for the crew conducting the flushing, the NO-DES Zero-Discharge Flushing System can often flush an entire network of mains from the one connection, by using the valves of the system to redirect the flushing flow to additional mains. This means even less water is wasted since the hoses only need to be hooked up once and saves work for the crew as they can keep the truck where it is and run a large area of the flushing operation from that single location.

Flushing a water-delivery system using the NO-DES Zero-Discharge Flushing System eliminates the problems of the old hydrant wasting method, while the filtration system and pressure pumps make the labor and time investment money well spent.

NO-DES, Inc. provides cutting-edge water management and treatment solutions to municipalities around the country. To learn more, contact a team member today.