The Altoona Water Authority Thursday awarded a pair of contracts totaling $4.8 million for replacement of the ozone disinfection systems at its Horseshoe Curve and Kettle water treatment plants.

The authority will pay low bidder HRI Inc. of State College $3.8 million for general-mechanical work and low bidder Bettwy Electric of Newry $960,000 for electrical work, according to Mark Glenn of engineering consultant Gwin Dobson & Foreman.

Adding the $3.4 million cost of equipment brings the total construction cost for the project to $8.2 million — $111,000 over the pre-bid cost estimate, Glenn said.

The contingency fund of $813,000 built into the cost of the project will cover that 1.4% overrun, Glenn said.

Both companies have done many projects for the authority and have the capacity to do the ozonation work, Glenn said.

The project could take about a year.

Because the Horseshoe Curve plant has redundant ozone systems, it will continue to operate during the project, according to Jim Balliet of Gwin.

Because the Kettle plant doesn’t have redundant ozonation capacity, it will need to be shut down for three or four months, Balliet said.

The authority will pay for the project with a $9.5 million low-interest loan that it received from PENNVEST in July.

That money will also pay for some additional work at the Curve plant.

The authority had initially hoped that some of the PENNVEST money would be in the form of a grant, based on PENNVEST adjustments a couple years ago to its affordability index, coupled with increases in the authority’s water rates.

The work at the Curve and Kettle plants will complete the ozone systems’ renewal at the authority’s set of six active water treatment plants.

The other active plants are Tipton, Mill Run, Plane 9 and Bellwood.

A plant in Homers Gap has been inactive for years.

Mirror Staff Writer William Kibler is at 814-949-7038.