Waste Water Treatment Plant Upgrades

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The City of Kingston received a renewed Individual State Pollutant Discharge Elimination System (SPDES) permit in late 2016 for the wastewater treatment plant (WWTP).

The new SPDES permit limits included an effluent ammonia nitrogen (NH3-N) summer concentration limit of 5.9 mg/l, and a winter concentration limit of 9.0 mg/l, requiring that the City treat wastewater to a much higher level of quality.

The SPDES permit also included an interim ammonia (as N) effluent limit of 25 mg/l, which was in effect while the City evaluated and upgraded the treatment system to meet the ammonia limit.

As a result, the City will modify the plant’s outfall, which is at the mean high water mark (MHWM) of the Rondout Creek, by constructing a new outfall discharging at a minimum of 20 feet below the water surface.

The site is located at 124-134 East Strand Street, Kingston, NY 12401. Existing conditions consist of a headwall structure with side‐wings and a concrete apron base, rip rap, and square timber piles held in place with rounded timber piles as the bulkhead. The existing outfall system consists of dual 20‐inch PVC outfalls installed through a headwall that also includes an 18‐inch diameter stormwater outfall; the outfall system consists of “Low” and “High” outfalls based on discharge elevation at the WWTP. The WWTP is north of the headwall structure and Rondout Creek. The headwall has side‐wings and a concrete apron base and was installed in 2001. The project’s original compliance schedule was June 1, 2018 with final plans and specification due within 12 months of NYSDEC approval of the Engineering Report.

The New York State Department of Conservation (NYSDEC) offered an interim extension period to implement the upgrade, and construction is scheduled to be in 2022. The WWTP alternatives were evaluated by Tighe & Bond, whose services in New York are provided by T&B Engineering & Landscape Architecture, PC (Tighe & Bond). The Main‐Stream Seasonal Treatment alternative had the best outcome for meeting limit levels and cost. This alternative evaluates seasonal ammonia removal in mainstream flows to meet the revised ammonia limits with a minimum of twenty feet of water above the outfall terminus. The proposed ammonia limits are 18 mg/L from June 1 to October 31, and 29 mg/L from November 1 to May 31.

The project will install the water-side portion of the outfall extension at a location to allow discharge of the WWTP effluent into the Rondout Creek in an area with a minimum of twenty feet of water above it. To accommodate this, the outfall will be reconfigured from the existing conditions, and discharge piping with restraint and protective structural systems will be installed. The proposed work consists of installing two new 28” diameter pipes to extend 62 feet 3 inches into Rondout Creek from the proposed bulkhead structure.

Due to the location within an Environmental Justice area (EJ), the city has prepared this Public Participation Plan. The map below depicts the project area and area of possible impact.



The City of Kingston received a renewed Individual State Pollutant Discharge Elimination System (SPDES) permit in late 2016 for the wastewater treatment plant (WWTP).

The new SPDES permit limits included an effluent ammonia nitrogen (NH3-N) summer concentration limit of 5.9 mg/l, and a winter concentration limit of 9.0 mg/l, requiring that the City treat wastewater to a much higher level of quality.

The SPDES permit also included an interim ammonia (as N) effluent limit of 25 mg/l, which was in effect while the City evaluated and upgraded the treatment system to meet the ammonia limit.

As a result, the City will modify the plant’s outfall, which is at the mean high water mark (MHWM) of the Rondout Creek, by constructing a new outfall discharging at a minimum of 20 feet below the water surface.

The site is located at 124-134 East Strand Street, Kingston, NY 12401. Existing conditions consist of a headwall structure with side‐wings and a concrete apron base, rip rap, and square timber piles held in place with rounded timber piles as the bulkhead. The existing outfall system consists of dual 20‐inch PVC outfalls installed through a headwall that also includes an 18‐inch diameter stormwater outfall; the outfall system consists of “Low” and “High” outfalls based on discharge elevation at the WWTP. The WWTP is north of the headwall structure and Rondout Creek. The headwall has side‐wings and a concrete apron base and was installed in 2001. The project’s original compliance schedule was June 1, 2018 with final plans and specification due within 12 months of NYSDEC approval of the Engineering Report.

The New York State Department of Conservation (NYSDEC) offered an interim extension period to implement the upgrade, and construction is scheduled to be in 2022. The WWTP alternatives were evaluated by Tighe & Bond, whose services in New York are provided by T&B Engineering & Landscape Architecture, PC (Tighe & Bond). The Main‐Stream Seasonal Treatment alternative had the best outcome for meeting limit levels and cost. This alternative evaluates seasonal ammonia removal in mainstream flows to meet the revised ammonia limits with a minimum of twenty feet of water above the outfall terminus. The proposed ammonia limits are 18 mg/L from June 1 to October 31, and 29 mg/L from November 1 to May 31.

The project will install the water-side portion of the outfall extension at a location to allow discharge of the WWTP effluent into the Rondout Creek in an area with a minimum of twenty feet of water above it. To accommodate this, the outfall will be reconfigured from the existing conditions, and discharge piping with restraint and protective structural systems will be installed. The proposed work consists of installing two new 28” diameter pipes to extend 62 feet 3 inches into Rondout Creek from the proposed bulkhead structure.

Due to the location within an Environmental Justice area (EJ), the city has prepared this Public Participation Plan. The map below depicts the project area and area of possible impact.



Page last updated: 04 May 2022, 10:07 AM