BUTLER TOWNSHIP — Butler Area Sewer Authority customers will have a monthly increase of $1 to their bills starting July 1, with another projected increase next year as the authority looks to pay for a $10 million bond issue that will update sewage treatment infrastructure.

BASA board members Tuesday approved the $1 monthly increase.

The rate increase will bring the monthly bills of residential customers to $33, according to a budget narrative provided by BASA executive director Tom Rockovich

Industrial and commercial rates also will be increased, Rockovich said.

Because of the authority’s billing schedule, customers won’t see the rate hike on their bills until Oct. 1.

The rate hike will raise about $556,000 for the authority’s 2015-16 proposed $9.84 million budget, Rockovich said.

That budget projects an increase in expenditures of $483,450 from this year. Nearly half of that increase will go for an interest-only payment on new borrowing, according to authority officials. Other cost increases in the draft budget include more than $77,000 in new capital improvement spending and about $170,000 in increased operating costs.

The rate increase, Rockovich said, will be used to fund an interest payment on a $10 million bond issue that’s expected to be issued either in late 2015 or early 2016, as well as capital improvement and operating costs.

The new borrowing will pay for infrastructure upgrades at the authority’s treatment plant, where Rockovich said upgrades to pollution reduction and solids-handling equipment could reduce the number of man-hours spent manning the facility.

He said plant workers staff the facility 24-hours-a-day, five days a week. Rockovich hopes to trim that to eight hours a day, five days a week, though on-call procedures over the weekend would remain in place.

The authority serves more than 22,000 sewer hookups in Butler, Butler Township, Center Township, Oakland Township, Summit Township, East Butler and Connoquenessing Township.