HARRISBURG — Residential customers of Pennsylvania American Water are now paying more for their water under a rate increase approved Thursday by the state Public Utility Commission.

The increase, which was effective Friday, will boost 16,500 Butler County customers' bills by about $2.70 per month.

About 700 customers in the Connoquenessing area can expect an extra charge of $11.16 per month for water, going from an average of $31.48 to $42.64.

That's a jump of 35.5 percent, while the rest of the customers' bills will increase by 6.8 percent.

This increase means about $36 million in additional revenue for the water company.

Joi Corrado, company's communication manager, said Friday the difference in price increases is the result of bringing Connoquenessing customers up to the same rate level as the rest of its customers in the county.

"When we acquire a system, like Connoquenessing, we try to bring the rates along gradually," Corrado said.

From now on, she said, increases in rates will be the same for all county customers.

The last increase the PUC approved for Pennsylvania American came in January 2004, and Corrado said the company has made about $490 million in improvements since then.

She said the company makes improvements to its systems, such as treatment plants and water lines, and then files for a rate increase to recoup those expenses.

Corrado said Pennsylvania American has made these improvements to the Butler system:

n Installed 47,690 feet of water main extensions, including a major main extension project in Center Township

n Replaced 21,750 feet of aging water main lines

n Installed or replaced 100 fire hydrants

n Upgraded filter controls at the water treatment plant

n Installed new radio telemetry system to improve data communications between treatment plant, tanks and booster stations

n Replaced the lower section of the spillway at Lake Oneida dam.

There was outcry from customers against Pennsylvania American's original April rate hike filing for a 14.7 percent increase. The company negotiated Thursday's settlement with the state Office of Consumer Advocate.

Corrado said the PUC is reporting the overall approved rate increase is 8.9 percent, but that it is really 6.8 percent when the distribution system improvement charge is removed from the formula.

This charge is added to customers' bills to help pay for new pipelines, hydrants and meters between rate increases, and is capped by the PUC.

In July, the PUC increased the cap from 5 percent of a customer's bill to 7.5 percent. Corrado said the charge was added incrementally to bills, with customers paying the full 7.5 percent on their October bills.