Like it or not, a new era comes to Fresno on Monday. Workers will begin installing the first of more than 100,000 residential water meters in a city that for decades has charged flat rates for unlimited water use.

Metered water bills, however, may not begin arriving in mailboxes for months as the city completes a major overhaul of its billing system.

City officials said Monday is a historic day in Fresno, where some residents have fiercely opposed meters, even writing a prohibition into the city's charter. State law and a federal water contract finally forced the issue.

"Meters are coming, whether people want them or not," said Public Utilities Department assistant director Robert Andersen, who is overseeing the installation project.

Once in operation, the electronic meters will transmit readings every six hours to city computers. Andersen said the meters are accurate and won't generate the controversy that has plagued PG&E's efforts to electronically read its electric meters.

"These are meters that have been used and tested for years," Andersen said.

Two neighborhoods -- one near the Tower District, the other in central Fresno -- will be part of a pilot project to see if the meters work as advertised. Each neighborhood, a half-mile square in size, has about 500 single-family houses.

Ten houses in each pilot area already have meters, installed recently by two companies hired by the city. City officials wanted to make sure the companies did quality work.

City officials said it should take several weeks to install the meters and test their accuracy. If the meters pass, crews from the two companies will get the green light to install meters elsewhere.

Crews will begin work in central Fresno and, moving clockwise, follow a schedule that culminates in late 2012 in the northeast.

A 2013 deadline

City officials said installing the meters is the easy part. The more time-consuming task is installing the meter box, usually in front of the house. City officials said all Fresno homes should have water meter boxes -- installed by two companies, one of them also doing meter installations -- by fall 2011.

About 24,000 single-family houses already have water meters, most installed over the past 18 years by state law in newer homes. These meters are not currently being read. City officials said all of these meters must be replaced because they are too old or aren't compatible with the city's new meter-reading system.

If all goes according to plan, each single-family house in Fresno will have an operating water meter within 30 months.

But nothing has been easy in the city's rocky journey toward the pay-for-what-you-use world of water consumption, and these next steps are no exception.

City officials are confident their contracted crews will finish work by January 2013. That is the federally mandated deadline if the city wants to continue receiving 60,000 acre feet of Central Valley Project water every year -- about 40% of the city's annual need.

But behind the scenes, city officials are hustling to overhaul a seemingly mundane yet pivotal piece of the transformation -- billing.

Revamping water bills

Residential customers currently receive a utility bill every two months that includes a flat-rate charge for water based on lot size. The billing cycle is based on when a customer begins service. This means next-door neighbors may receive utility bills in separate months. City officials said they want to reform billing at the same time they reform how residential water is priced, going to uniform monthly billing.