Authority plans water treatment plant upgrades

Renovation projects to take place at six of seven facilities

The Altoona Water Authority has begun planning for major upgrades at all but one of its seven water treatment plants -- two of them in conjunction with renovations of their associated dams.

The projects, slated to be complete by the end of 2027, could cost close to $48 million, not counting the dam renovations.

The main elements of the upgrades will be replacement of "traveling bridge" sand filter systems in five plants with membrane systems that can trap smaller pathogens and the replacement of obsolete ozone preliminary disinfection systems in six plants with liquid-oxygen-fed ozonation.

The plans call for financing the work through Pennvest.

The authority applied in December for permits from the state Department of Environmental Protection for replacement of the ozonation systems at Tipton, Mill Run and Plane Nine, according to a project timeline provided by staff engineer Mike Sinisi.

The authority expects to receive permits in the second quarter of this year, at which time it will apply to Pennvest for funding, according to the chart.

The ozonation replacements could cost about $1.3 million each, Sinisi estimated.

Construction could begin at Tipton in the fourth quarter of this year, according to the chart. Tipton is where the need is most urgent, because of a problem in the ozone system that requires it to be operated manually. A replacement part is no longer available for the old equipment, Sinisi said.

Construction at that plant could be complete in the first quarter of 2021, about the time construction could begin on replacement of the ozonation system at Mill Run. That construction would end in the second quarter of 2021, when construction would begin at Plane Nine.

That project would end in the third quarter of 2021, according to the chart.

Engineering work has been underway for years on the simultaneous renovation of the Bellwood treatment plant and the dam that creates the reservoir that provides the water processed in the plant.

The authority expects to receive a permit for the plant upgrade in the first quarter of this year and for the dam renovations in the second quarter, after which it would apply for Pennvest funding for both projects.

The plant project, which will include re-roofing, could cost $8.5 million, including the $3.2 million cost of the filtration system, according to Sinisi.

The dam project could cost $12 million, according to previous estimates from the authority's consulting engineer, Gwin Dobson & Foreman.

Construction on the plant and the dam could begin in the second quarter of 2021 and be complete two years later, according to the chart.

Engineering could begin on ozonation replacement at the Horseshoe Curve and Kettle treatment plants in the third quarter of 2022. Construction could begin in the third quarter of 2023 and be complete toward the end of that year.

Engineering could begin on the Mill Run plant and its dam renovations in the fourth quarter of 2022. Construction on both projects could begin near the end of 2025 and end around the close of 2027, according to the chart.

Engineering on membrane filtration for the Kettle plant could begin in the fourth quarter of 2024. Construction could begin near the end of 2025 and end in the second quarter of 2027.

The authority has seven water treatment plants, but the one at Homers Gap is "mothballed," Sinisi said.

The membrane systems will replace sand filters at all the other plants, except the plant at the Curve, which has a regular filtration system.

Membrane filtration employs a more definitive barrier against contaminants. It uses perforations to remove impurities rather than the trapping effect of granular media, after contaminants have been enlarged by "flocculation" -- combining with chemical additives.

The membrane perforations or pores will be from 0.1 to 0.01 microns across, as stated previously by a Gwin engineer.

For the treatment plant projects, the authority hopes to take advantage of an "innovative financing vehicle" recently adopted by Pennvest. It replaces funding allocated for single projects with a package that matches a local agency's capital improvement plan, provided each of the projects is eligible according to Pennvest standards, stated authority controller Gina DeRubeis and a Pennvest "guidance" sheet that she provided.

Mirror Staff Writer William Kibler is at 949-7038.