May-June 2008

Money Down the Drain

A recent survey by the Golf Course Superintendents Association of America (GCSAA) reveals that 29% of 18-hole golf course facilities voluntarily participate in an environmental stewardship program.

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By Nikki Stiles

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Unaccounted-for water usage at water utilities is like throwing money down the drain. Aging water meters often lose accuracy in measuring water usage over time, which adds up to large revenue losses for water utilities. There are several types of water meters commonly used. Selection is based on different flow-measurement methods, the type of end user, the required flow rates, and accuracy requirements. In the US, standards for the manufacturing of water meters have been established by the American Water Works Association. There are three common types of flow measurement: displacement, velocity, and electromagnetic.

Displacement meters are the type of meters most often used in residential and small commercial applications. Displacement meters are commonly referred to as Positive Displacement (PD) meters. Two common methods of PD measuring are Oscillating Piston meters and Nutating Disk meters. Both methods require water to physically displace the moving, measuring element in direct relation to the amount of water that passes through the meter. The piston or disk moves a magnet that drives the register. PD meters are generally very accurate at low- to moderate-flow rates.

Velocity water meters measure the velocity of flow through a meter of a “known internal capacity.” The speed of the flow can be converted into volume of flow for usage. These types of meters include jet meters, turbine meters, propeller meters, and magnetic-flow meters.

Magnetic-flow meters commonly referred to as “mag meters” are technically a velocity-type water meter, except that they use electromagnetic properties to determine the water flow velocity rather than mechanical means, which jet and turbine meters use. Mag meters use the physics principal of Faraday’s law of induction for measurement, and require alternating current or direct current electricity from line or battery to operate the electromagnets.

There are several types of registers for water meters. A standard register normally has a dial similar to a clock with gradations around the perimeter, to indicate water usage measured by the meter, as well as a set of odometer wheels. Modern registers are normally driven by a magnetic coupling between the magnet in the measuring chamber attached to the measuring element, and another attached to the bottom of the register. Gears in the register convert the motion of the measuring element to the proper usage increment, for display on the sweep hand and the odometer.

Many towns and cities are now using automatic meter reading (AMR). There are also some specialized types of registers such as liquid crystal display, instead of mechanical odometers, and registers—to output data or pulses to a variety of recording and controller devices. This new technology also includes products developed, that have developed pulse or encoder registers to produce electronic output for radio transmitters, reading storage devices, and data-logging devices. Pulse meters send a digital or analog electronic pulse to a recording device.

Tyler, TX, Upgrades and Saves
“Water Meters are mechanical, and they have a mechanical chamber that measures and moves in the water meter,” says Steve Zip, Account Executive for Government Solutions, for Johnson Controls. “So, over time, with impurities in the water and ongoing usage of that meter, the meter will degrade and slow down.”

Upgrading these water meters can be costly, inconvenient, and time-consuming, but the end results can be very beneficial for utilities. Nobody knows this better than the City of Tyler, TX. The city hired Johnson Controls to test its existing 31,000 water meters, which had an average age of 10 years. Johnson Controls, headquartered in Milwaukee, WI, provides a wide-range of products and services to optimize energy use. The company found that the city was losing approximately a whooping $2.2 million a year, due to faulty water meters.

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The City decided to enter into a performance contract with Johnson Controls to upgrade their water meter system. Performance contracts have been around for decades, but are not typically used in the water industry. “A performance contract is something that has been traditionally done for energy usage for large buildings, cities, counties, school districts, or universities,” Zip says. “It is a contract where we do an audit and calculate savings, or find increases in billable usage.”

The performance contract guaranteed $29 million over a 10-year period from increased billable water usage and energy savings. The contract not only focused on water, but also included savings by upgrading HVAC at city facilities, and upgrading traffic signals. “When we put together a performance contract for a customer, we actually take a risk in the project, so that, if the customer does not achieve the results that were guaranteed to them in the contract, then we will make up the shortfall,” Zip says. Next Page >

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watergrrll

August 4th, 2008 11:38 AM PT

All golf courses should be required to conserve and reuse water.

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