Waco City Council on Tuesday authorized $90 million in certificates of obligation, setting the stage to start a large-scale overhaul of its sewer and water systems.

The bonds, which are expected to be sold in early 2016 in tandem with a utility rate hike, will allow the city to replace miles of decades-old water and sewer mains, mostly in the older parts of town. The city would spend $36 million to relocate a failing sewer transfer station near the Brazos River and $15.7 million to replace the 1920s-era ground storage tank near the Waco Police Department tower.

In all, the city will use the bonds for $54.9 million of sewer improvements, $29.7 million of water improvements and $4 million of building renovations and street improvements.

Mayor Malcolm Duncan Jr. said the city can’t afford to put off these costly projects any longer.

“We have to do it,” Duncan said. “Look at all the (utility) failures we’ve had this year.”

He pointed to the sewer main collapse that shut down Martin Luther King Jr. Boulevard for weeks this summer.

“All that was the result of deferred maintenance,” Duncan said.

Other infrastructure emergencies this year included a broken raw waterline at the Mount Carmel Treatment Plant and the collapse of a concrete sewer line near La Salle Avenue that carried most of the area’s waste.

The first of several annual rate increases to fund the utility improvements begins in January.

The typical combined sewer and water bill for customers using 8,000 gallons of water a month will increase by $4.66 a month, rising from $62.77 to $67.43. That bill could gradually increase to $92.35 by 2025 as part of the proposed 10-year plan for $245 million in utility improvements.

Duncan said the improvements are an investment in the city’s future.

“It’s the ability to handle growth when we get it,” he said.

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