Contractors from ABCO Enterprises replace old lead water supply pipes, below, from the main line to the curb, with new copper lines for Providence Water along Broad Street in Providence. Joe Girardi, left, and Dante DelGiudice of ABCO repair the lines.

The Providence Journal / John Freidah

Thousands of Rhode Islanders are seeing higher water bills as the Providence Water Supply Board is increasing its rates by about 6 percent. The rate hike applies to water usage since Oct. 5.

For the average household, which uses about 75,000 gallons of water a year, the water bill will go from $276.32 to $293.16 per year, an increase of $16.84. The average commercial customer would see an annual increase from $4,282.92 to $4,544.20, an increase of $261.28.

Providence Water supplies water directly to 73,800 customers, including homes and businesses, in Providence, North Providence, Johnston and Cranston, and also sells water wholesale to other water systems in the state. It provides approximately 60 percent of the drinking water in the state.

Pamela M. Marchand, Providence Water’s chief engineer and general manager, said the rate increase is necessary to help pay for two major infrastructure projects, renovating the water treatment plant in Scituate and replacing lead water pipes throughout the system.

Under an order from the Environmental Protection Agency, Providence Water must replace at least 7 percent of its lead service lines each year. Marchand said that’s a 15-year project that costs $10 million per year. Providence Water is also working to either renovate or replace its larger water mains, a quarter of which were installed before 1900.

At the water treatment plant in Scituate, Marchand said, Providence Water is beginning a five-year, $40-million upgrade that includes a renovation of the filtration system, parts of which date to 1926. The work will boost plant capacity from 144 million gallons a day to 180 million gallons per day.

The current rate increase is not as high as originally proposed. In late April, Providence Water went to the state’s Public Utilities Commission to ask for a 10-percent rate hike. The 6-percent increase was agreed to after a series of negotiations between Providence Water and the state. Providence Water’s last rate hike, a 13.6-percent increase, took effect in November 2007.

Marchand said the original request was based on expenditures from 2008, and that several elements had changed since then, among them lower chemical costs and savings in salary and benefit costs as a result of negotiations between Providence and Local 1033 of the Laborer’s International Union of North America.

The Providence Water Supply Board also negotiated a tax settlement with the Town of Scituate that reduces the amount of property tax Providence Water must pay in 2010 by $694,933. Providence Water owns 42 percent of the acreage in Scituate, home to the largest of the six reservoirs in the water system.

The water board sells about 10.2 billion gallons of water each year. Aside from government use, Rhode Island Hospital is Providence Water’s largest single customer.

About 60 percent of the water sold by the board goes to its direct-sale customers in Providence, Cranston, North Providence and Johnston. Providence Water also supplies water at wholesale rates to water systems in Kent County, Greenville, Smithfield, East Smithfield, Lincoln, East Providence, Warwick and Bristol. Those rates are also going up by about 6 percent.

asmith@projo.com