Derby WPCA Engineers Say Connecting To Ansonia Isn’t So Simple

Pumping Derby sewage to Ansonia is anything but a “no-brainer,” engineers working for Derby’s Water Pollution Control Authority told elected officials last month.

“Eventually this may be a possibility. Right now, it’s not,” said Chris Wester, a vice president with Weston and Sampson, the engineering company Derby uses as a consultant on sewer issues.

Wester and Anthony DeSimone, another engineer from Weston and Sampson, appeared with WPCA chairman John Saccu at the Derby Board of Aldermen meeting Feb. 27 to talk about connecting to Ansonia’s recently upgraded sewage treatment plant.

According to minutes from the Ansonia Water Pollution Control Authority (posted below), Derby Mayor Anita Dugatto and Ansonia Mayor David Cassetti have requested that the state Department of Energy and Environmental Protection conduct a study to see whether connecting the two cities is feasible.

The mayors were also scheduled to meet with elected officials in Middletown, where a sewer regionalization project is underway with Cromwell, according to the same meeting minutes.

However, last month Derby’s WPCA engineers stressed — repeatedly — that tons of work has to be done on Derby’s infrastructure regardless of whether the city starts pumping sewage to Ansonia’s treatment plant.

In addition, Wester cast doubts on whether Ansonia’s treatment plant can actually handle Derby’s flow.

Millions And Millions Of Sewage

Wester gave Derby Aldermen data showing Derby’s sewage treatment plant handles 1.6 million gallons of waste water a day.

Ansonia handles about 1.8 million gallons on a normal day, Wester said. So, that’s a combined 3.4 million gallons a day between Ansonia and Derby.

But Wester said Ansonia’s treatment plant can only handle 3.5 million gallons a day.

There’s not much wiggle room there, Wester said, and the limitations could have an impact on economic development in Derby.

“We are going to create 3.4 million combined. They can only treat 3.5 million,” he said. “That means the City of Derby, the way it is set up today, will not have the ability to expand, will not be able to add flow into the system. Development in the city stops at that point because you no longer have the ability to push flow into the other community.”

In 20 years, Derby predicts the city’s sewage plant will see 2.4 million gallons per day.

“We need more capacity. Ansonia’s plant probably does not have it,” Wester said.

Derby’s Treatment Plant Is Drowning In Storm Water

But there’s an even bigger hurdle for Derby to overcome, Wester said. It’s something the waste water experts call “i and i,” or “inflow and infiltration.”

It is a term describing stuff that gets into the sewer system, but isn’t supposed to be there.

Infiltration is a major problem in Derby’s aging and neglected sewer system. Tons of storm water goes into the sewer system during heavy rains, overwhelming the city’s pump stations and main treatment plant.

During a heavy rain, 13 million gallons can flow into Derby’s sewage treatment plant — one that was designed to handle just 1.6 million.

Before connecting to Ansonia, Derby has to get all that extra liquid out of its sewer system.

The WPCA is working on it. Last year they did “smoke testing” to identify places where storm water seeps in. The smoke testing alone identified 360 potential trouble spots.

In the next few weeks there will be dye testing and, perhaps in the summer, in-home visits to pinpoint problem areas.

The WPCA suspects many homes been built over the years simply connected downspouts and sump pumps to the sewage system, which is a no-no. Getting those corrected is a big job.

Reducing the “i and i” is a process that will take seven to 10 years, the Derby WPCA engineers said, and it must be done before the city connects to the Ansonia treatment plant.

“Getting the flows down to where we need them to connect to Ansonia cannot happen overnight,” Wester said.

The engineer also said there has been “confusion” in Ansonia and Derby about connecting the two systems.

Generally, Ansonia officials have been in favor of it over the years, while Derby officials have not been clamoring to get it done as fast as humanly possible.

Wester said Ansonia last year circulated a document severely underestimating the amount of infiltration that enters into Derby’s sewers during a heavy rain.

Wester believes Ansonia was citing a 2007 document from Derby that applied to only a fraction of the city’s population.

“We think they are using numbers that aren’t actually representative of the numbers we are seeing here,” Wester said.

And, While We Have Your Attention

The Derby WPCA and the engineers stressed two other points to the Aldermen back in February.

Even if Derby starts pumping sewage to the Ansonia treatment station, that sewage will still have to pass through Derby’s plant, and Derby’s sewer system still needs $24 million worth of repairs, they said.

The repairs need to be done even if the city decides tomorrow it wants to connect to Ansonia’s treatment plant, the engineers stressed.

Saccu said the WPCA hopes to put the matter to voters within the next five months. It’s an issue that has been kicking around the city for two years.

Click here to watch videos from 2013 in which WPCA officials and representatives discuss why the repairs are needed.

The $24 million in repairs breaks down like this:

  • $6.8 million for upgrades to the Roosevelt Drive waste water pumping station
  • $751,000 for upgrades to the South Division Street waste water pumping station
  • $958,000 for upgrades to the Burtville Avenue pump station
  • $9 million in upgrades and repairs to the city’s waste water treatment plant
  • $3.4 million to replace a force main from the Roosevelt Drive pump station
  • $3.3 million to replace a stretch of sewer at Route 34

DeSimone, another Weston and Sampson engineer, noted the project does not involve building a new waste water treatment plant, something that apparently gets lost in stories and conversations on this topic.

The $9 million is to replace equipment that met its life expectancy 10 years ago.

“We are not rebuilding our plant. It does not need to rebuilt. We’re replacing the equipment that the guys use every day. It is 30 years old. It has a design life of 20 years. It’s at the end,” DeSimone said.

Ansonia WPCA March 2014


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