Study will tackle nitrogen output

City’s wastewater treatment plant faces upgrade to meet new pollution standards

City officials are preparing to finalize a contract with a consultant to determine how to reduce nitrogen content in treated sewage at the city’s wastewater treatment plant on East Strand.

Too much nitrogen in a water body encourages the growth of algae, which robs the body of oxygen and can lead to fish kills. Treated sewage from the city’s plant empties into the Rondout Creek, which flows into the nearby Hudson River.

City Engineer Ralph Swenson said he has recommended to Mayor Steve Noble that Tighe & Bond, a Rhinebeck engineering firm, be hired as a consultant on the project. The same firm was recently hired by the city to conduct a $50,000 study of the Twaalfskill Creek, which will include identifying stormwater flows along the entire waterway. Swenson said that study is not yet complete.

Swenson said the latest contract will not be finalized until Noble signs off on it.

Six consulting firms had submitted proposals to draw up an “options plan” as part of an effort to treat nitrogen at the wastewater treatment plant. Swenson said the city is looking for options to reduce the cost — currently es-

timated at $7.9 million — to meet new state requirements.

The report will also examine the possibility that the nitrogen work be done in conjunction with other

required projects to separate the city’s stormwater and sewage flows, Swenson has said.

In July, the Common Council approved borrowing $1.2 million for engineering, design and administrative services to upgrade the wastewater treatment plant so that it meets the state Department of Environmental

Conservation’s more stringent effluent standards.

Swenson said that the cost of developing the report may decrease as it progresses.

“It will be a work in progress,” Swenson said. “It may cost close to ($1.2 million) or it may be a fraction of that.”

Swenson has said the

treatment plant improvements are necessary due to a change in the city’s State Pollutant Discharge Elimination System (SPDES) permit from the state Department of Environmental Conservation.

The city was notified of the change in late October 2017. The new discharge parameters go into effect in

about three and a half years, Swenson said in a letter to Common Council President James Noble.

Swenson said the state is requiring the city to treat for nitrogen above and beyond what it currently does, which will require changes in some of the processes at the treatment plant.

The city currently is involved

in an unrelated repair and upgrade project at the wastewater treatment plant, costing about $3.3 million.

Much of the cost for that work is expected to be reimbursed by the Federal Emergency Management Agency because some of the repairs and upgrades were due to flooding during Superstorm Sandy in October 2012.