Bills for natural gas are going up in Lawrence, effective today.

Aquila Inc. said Thursday that it had received approval for collecting another $5.1 million a year from its 106,000 customers in Kansas, including about 33,000 in Lawrence.

The increase, approved by the Kansas Corporation Commission, means that the typical residential customer will pay another $3.64 a month, while small-commercial customers will spend another $4.99, the company said.

The increase is less than the company’s original request for an additional $7.2 million in revenue each year, which would have boosted a typical residential customer’s monthly bill by $4.40.

Aquila had argued that it needed the higher amount to offset its cost increases for health insurance, motor fuels and other products and services necessary for keeping the operation’s 4,000 miles of Kansas gas lines in service.

After the commission accepted public comment, conducted hearings and met with company officials, Aquila agreed to a settlement that allows for boosting annual revenues by $5.1 million.

“We respect and support the process that is in place to set rates for our customers while considering increasing operations and maintenance costs and our responsibility to continue providing safe, reliable service to our customers,” said Chuck Loomis, operating vice president for Aquila in Kansas.

The Citizens’ Utility Ratepayer Board, a state-mandated agency that studies utilities’ rate requests on behalf of residential and small-commercial customers, had argued that Aquila’s requested rate of return for company shareholders – 12 percent – would have outpaced the 11.2 percent previously sought by Kansas Gas Service and 10 percent previously granted to Westar Inc. for electric service.

Bills reflecting Aquila’s new rates will be sent to customers in July, said Curt Floerchinger, a company spokesman.

Aquila’s natural gas operations in Kansas are based in downtown Lawrence, at Ninth and New Hampshire streets.