June 18, 2010 By Karen Wilkinson
San Francisco started replacing its 175,000-plus water meters in June with high-tech devices that will eventually allow customers to view their water use online and eliminate the need for manual meter readers.
The San Francisco Public Utilities Commission (SFPUC) on June 7 began its automated water meter program, a two-year effort to replace all residential and commercial water meters in the city. The new meters use low-frequency radio signals to collect hourly water use and transmits that data four times a day to the SFPUC billing system. The $50 million program is being funded by a 91-cent fee that's being tacked onto ratepayers' monthly bills.
"It's a great tool in looking for potential spikes in usage and leaks," said Heather Pohl, SFPUC automated water meter program project manager. "So we can, in real time, help people monitor and manage their water use more effectively."
While San Francisco's utility commission is the first major California water utility to install the technology, according to the SFPUC. The utility is following a nationwide trend of other cities that have deployed similar technologies. Boston; Washington, D.C.; and Kansas City, Mo., use the same meter-reading system, and New York City and Toronto are starting extensive projects with the same technology, according to a SFPUC frequently asked questions page.
Public utilities across the country have also started installing smart electricity meters with similar functionality in millions of homes and businesses.
Currently most residential water meters are read by meter readers once every two months, and commercial meters are read every month. But this "intensive and infrequent" process can result in bill estimations when the readers can't be accessed due to parked cars and other obstructions. It also doesn't allow for water leaks to be quickly detected, which can result in more expensive monthly bills. The automated water meter system will nix both issues by collecting more frequent consumption data and flagging water consumption surges.
Eventually the commission hopes to send e-mail alerts to customers if there's an unusual amount of water being used, which may allay undetected leaks.
"If they've got a leak now, and toilet leaks happen every day, they can result in a lot of water loss, and right now they won't know," Pohl said. "It gives them tools to understand what they're paying for."
The automated water meter system -- brand name Aclara Fixed Network AMI STAR System -- uses a wireless fixed network system with three components. The meter transmission unit, connected to the water meter, "reads" the meter every hour and sends its information to the data collection unit every six hours.
There will be about 70 data collection units throughout the city on SFPUC facilities and city-owned poles and rooftops, which will transmit meter readings to the SFPUC's network control computer. The network control computer feeds into the SFPUC's billing system and calculates the amount of water used, creating statements.
The meter readings are transmitted via the automated network using a private radio frequency channel, from the meter box to data collectors, and using a cellular data network from the data collectors to the network control computer.
Due to public safety concerns about radio frequency exposure levels, the SFPUC partnered with the Department of Public Health to evaluate the automated water meters' transmission levels. The signals turned out to be "well below" government limits with respect to radio frequency exposure levels, according to the SFPUC.
The technology has proven itself effective, and has been in use for more than 13 years, the SFPUC assures. Privacy concerns -- that personal customer