Combined Sewer Overflow: Challenges & Solutions

City of Poughkeepsie Mayor Robert Rolison, City Engineer Greg Bolner and Commissioner of Public Works Chris Gent, as well as Riverkeeper Director of Water Quality, Dan Shapley, appear in a newly produced video to explain how the City is addressing challenges posed by increased rain and snowfall that saturates the ground and contributes to some diluted sewage being discharged into the Hudson River.

New video explains the challenges and solutions the City of Poughkeepsie is using to address recent publicity about sewer discharge into the Hudson River

Sewage Going Into the Hudson River

Much of the City of Poughkeepsie's sewer system is almost a century old. At the time it was built the best practice method of collecting sanitary sewage, rainwater runoff and industrial wastewater was to combine all of them in one pipe and bring it to the Water Pollution Control facility. As is common with many waterfront cities around the world, this Combined Sewer method is still used in the older parts of the City. Areas such as the residential neighborhoods south of the eastbound arterial and along Hooker Avenue are served by combined sewers.

In newer sections of the City, the system is already designed to separate sanitary sewage from storm water. That enables the sanitary sewage to be treated without overwhelming the system.

There are certain locations within the system that are called Combined Sewer Overflows or CSOs. These include:

  • The Water Pollution Control Plant
  • Riverview CSO
  • Albany Street CSO
  • Mill Street CSO
  • Pine Street Pump Station CSO
  • Pine Street CSO

Although these locations are called Combined Sewage Overflows, most of them rarely actually overflow. These locations are entirely in compliance and permitted under the coverage of the State Pollution Discharge Elimination System or SPEDS permit, issued by the New York State Department of Environmental Conservation.

The times when actual overflows occur is when there is a great deal of snowmelt, or the ground in the City is completely saturated, when the system exceeds capacity. If there is so much volume hitting the CSO locations, it can only be relieved with a discharge through a pipe that takes some sewage which is heavily diluted by stormwater and discharges it into the river.

There are 800 permitted CSO locations in the whole of New York State and Poughkeepsie has only six of them. Almost every waterfront city from Poughkeepsie, NY to London, England are working to modernize their systems to prevent any sewage overflow ending up in any body of water. Poughkeepsie is not alone and it is in compliance with all regulations.

Media Coverage

In the past year, a new state law came into force called the Sewage Pollution Right to Know act. All sewer overflow locations are posted on the Department of Environmental Conservation's website and each permit holder - such as the City of Poughkeepsie - are required to post signs when there's an outfall. The media sees the postings and covers the story. Here are the facts the public needs to know:

  • An overflow it is never only sewage
  • The sanitary sewage is always heavily diluted before it ever reaches the river
  • What triggers the permitted overflow event is a rain or snow event, and so the runoff further dilutes the sewage
  • When this happens Poughkeepsie is not out of regulation or compliance

Media Coverage Benefiting Poughkeepsie

According to Dan Shapley, Water Quality Director for Riverkeeper, The Sewage Right to Know law has made the public and state and federal officials more aware that money needs to be invested by cities like Poughkeepsie to stop these sewage overflows. The publicity got money flowing from the State and even the Federal Government to help communities like Poughkeepsie make these investments. The allocation of $2 ½ billion to the Clean Water Infrastructure Act in 2017 was the first step and that investment has since been doubled.

These grants have helped make a lot of the necessary work possible. Mayor Rolison commented "We have already spent millions of dollars making things better in our clean water and Water Pollution Control Systems and will continue to do so for years to come. We are incredibly grateful to Governor Cuomo for the funding that he and the state have made available through the Environmental Facilities Corporation which is helping to advance our long term plan.

Collaborations Are Key to Success

Poughkeepsie has been able to join with the other 46 New York communities that are facing these issues through collaborations with Riverkeeper and the Environmental Facilities Corporation (EFC). Mayor Rolison said, "the EFC gives us the opportunity to apply for monies that we couldn't fiscally do on our own. They've been great partners for the City of Poughkeepsie." This program of improvements is already showing success. According to Dan Shapley, "At the Poughkeepsie Launch Ramp, Riverkeeper's water quality sampling shows water quality that would meet federal criteria for safe swimming." The Mayor pointed out that swimming in the Hudson was unimaginable in the past.

Long Term Care Plan

Since 2008 the City of Poughkeepsie has had in place a Long Term Control Plan (LTCP) as part of its DEC permit that allows the city a period of time to start doing separation work and it is a schedule with milestones. Mayor Rolison and City Engineer Bolner explained that the City has already spent millions of dollars improving clean water and Water Pollution Control Systems and will continue to do so for years to come.

Funding for Improvements

The City of Poughkeepsie has already received:

  • $10 million to design improvements to the City's Wastewater Collection system
  • $11.2 million through Environmental Facilities corporation funding in the form of 0% interest loans and grants
  • $2 million is budgeted for design and construction of improvements to the city's sewer collection system, with the goal of eliminating the need for the Riverview CSO location
  • $700,000 dollars are budgeted towards improvements at the Pine Street Pump Station CSO
  • $1.4 million to investigate sources of inflow and infiltration - cracks and leaks
  • $650,000 dollars for a new roof on the pollution control plant building to protect this vital city asset
  • Approximately $1 million for porous paving for the Liberty Street Parking lot

Future Plans to Eliminate Sewage Discharge

Mayor Rolison said that the City of Poughkeepsie is committed to improving operations at the City's Waste Pollution Control Plant. He said, "Over time we want to limit the discharge of combined sewer into the Hudson River completely. The LTCP lasts until 2029 and we will probably not have completed all the work to modernize our system, but we will be well on the way."

Key Facts About Combined Sewer Overflow (CSO)

  • This is a permitted use regulated by a State Pollution Discharge Elimination System Permit, which is issued by the New York State Department of Environmental Conservation
  • This permit regulates the discharge of wastewater from the Water Pollution Control Plant, as well as the discharge of Combined Sewer Overflow (CSO)
  • Under the Sewage Pollution Right to Know, the permit holder (the City of Poughkeepsie) is required to report to the NY Alert System each time a CSO or Sanitary Sewer Overflow (SSO) occurs within the city's sewer collection system
  • The City of Poughkeepsie provides constant vigilance to protect the Hudson River