Many utilities, usually those with fewer than 500 customers, still collect meter readings manually. But those that can afford to amortize the cost of converting to automated systems are benefiting from more than lower labor costs. Depending on the technology they've chosen, they're finding and fixing leaks more quickly and enlisting ratepayers in conservation efforts.
There are three types of automated meter reading (AMR) methods:
- Walk-around. Meters are equipped to transmit readings to handheld devices; data are later downloaded to a central billing system.
- Mobile. Same as above, except that the data-collection units are located in vehicles, making the process of meter reading much faster.
- Fixed-network, or advanced metering infrastructure (AMI). Eliminates human intervention because readings are transmitted to collection points throughout a wireless network and then to a central data-collection point. AMI systems allow for robust water-system monitoring, largely because readings can be taken at shorter intervals and the higher volume of collected data allows for more in-depth analyses of water-system performance.
Since late last year, when the Consolidated Utility District of Rutherford County in Murfreesboro, Tenn., installed a radio frequency (RF) system on nearly 42,000 meters, Assistant General Manager William Dunnill, PE, has watched productivity and safety increase dramatically. The $6 million project used cash reserves that were repaid from a $20 million bond issue.
The meter-mounted RF signaling devices emit radio signals every few seconds to an RF receiver antenna connected to dedicated laptop computers via a serial port. The computers' GIS software shows all of the meters to be read on a given route. Employees return to the office and download the data from the laptops into the utility's billing system.
Previously, the utility sent out eight individuals per reading cycle, and each one required about six hours to complete a route. “A lot of our routes are rural with a lot of heavily traveled roads, but they're relatively narrow,” Dunnill says. “There wasn't a good spot to pull off and read a meter. And we had guys climbing fences and going through brush and wood to get to the meters.”
Now one employee reads all the meters in about four hours with few, if any, errors. “Our rereads have gone to virtually none,” says Dunnill. The conversion could free up about seven employees for other work, saving $390,000 — or almost 90% — annually.
Because the system records radio signals every few seconds and stores the data for two years, billing disputes are quickly settled. “When a customer says there's no way he used that much water, we pull his history and show his consumption every hour,” Dunnill says. “Customer service personnel discuss consumption intelligently instead of just saying, ‘Well, that's what our meter said; you've just got to accept it.'”
In Zachary, La., contracting out water and gas meter-reading for a 20-square-mile service area was costing more than $100,000 annually. Bills were being estimated, some meters hadn't been read for years, and city employees had to make rereads when more than one customer was tied into a meter.
Using $1.2 million from a bond provided by the state's Local Government Environmental Facilities and Community Development Authority, the city has retrofitted more than 12,000 commercial/industrial and residential meters since 2003. Master Meter Inc. RF signaling devices transmit signals to a data collector wirelessly using the provider's 3G technology.
In tests, one employee read 1,200 meters in two and a half hours by driving by — instead of walking up to — each one. The reader also uses Greentree Software Service's MasterLink software suite for route navigation.