John Purcell/Recorder staff

Amsterdam Water Treatment Chief Plant Operator Robert DiScenza on Thursday holds one of the new underdrains to be installed in a filtration tank at the city’s plant.

By JOHN PURCELL

Recorder News Staff

A project is progressing to rebuild the two most significantly damaged filtration tanks at the Amsterdam Water Treatment Plant, which is on track to be completed before the upcoming winter.

Koester, a Canastota-based company, began rebuilding the first filtration tank June 6 and to date has removed the damaged underdrain blocks, according to Amsterdam Water Treatment Chief Plant Operator Robert DiScenza. After tank No. 5 is rebuilt, contractors will begin rebuilding tank No. 6. DiScenza said the entire project would likely be completed late-September.

DiScenza said he will be “comfortable” running the plant through the next winter after these two tanks are replaced.

“In the winter, you have temperatures that are 2 degrees Celsius and it puts a lot strain on everything,” DiScenza said. “The warmer water is easier to treat, so we can do a larger amount without stressing the units.”

Not only is treating cold water more difficult, but the city’s plant generally experiences higher flows rates from January to February, according to DiScenza. He believes the influx is from residents concerned about their pipes freezing running their water, likely more than a steady drip, too.

“Generally, we don’t have the luxury of having a unit offline to get it repaired. We’re running all six units and one on standby,” DiScenza said.

Five filter tank units are running and another tank is on standby at the moment. Only one filter tank can be rebuilt at a time to ensure capacity needs are met.

City officials in February approved allocating $113,817 to replace two trident filter underdrains. Funds for the project were tapped from an unexpected savings Amsterdam realized after property reassessment deceased taxes on its 5,000 acres in the Town of Providence, which holds the city’s water reservoir.

Removing the underdrain blocks from the leveling grout holding it in place proved to be more difficult than contractors had expected, according to DiScenza. He said a hydraulic jack had to be used to remove the blocks from the bottom of the tank.

He hoped the new underdrain blocks and media could be installed by the end of next week.

DiScenza had described the seven filters as a key element of Water Treatment Plant operations and the rebuilds underway are considered to be an emergency project. Patchwork repairs over the years have sustained the two significantly damaged units, but they were nearing a potential total failure.

DiScenza said plant operators are not certain how badly damaged the other five filter units are at the moment, but these units have functioned better than the two being replaced. He said there is not an immediate concern for the other units.

Filtration tank No. 4 would be the first of the remaining units to be rebuilt, but whether other units must be rebuilt is unknown, according to DiScenza.

The remaining five filtration tanks are targeted to be rebuilt, if needed, through the city’s proposed $5.5 million water system improvement project. Local officials are hoping to secure $3 million of state aid for the project, which would reduce the city’s burden to $2.5 million.

Barton and Loguidice, an engineering firm, in March completed a report detailing its independent investigation of filter performance and damage at the Amsterdam Water Treatment Plant, which has experienced issues over the last six years. According to the firm’s report, a programming error when Siemens Water Technologies installed the new system was the key factor leading to filters being damaged.

Construction concluded on the upgraded water treatment plant in January 2011 and operations commenced with seven new mixed media Microfloc Trident water filters.

Soon after the new facility was operational, plant operators observed pressure irregularities during backwashing of the filters, which is the process used to clean the filters. The sequencing of filters valves were eventually discovered to be the culprit of pressure irregularities.

City officials are continuing to explore what action to take on the alleged programming error blamed for damaging filter units.