Combined Sewer Overflows (CSO)
- Live map showing current overflow discharge conditions (Quick Link)
- Canoe Creek Levels (24-Hour Graph) (Quick Link)
- Ohio River Levels and Rain Gauge (Quick Link)
- NWS Advanced Hydrologic Prediction Service (Quick Link)
What is the difference between a “Combined” sewer system and “Separated” sewer system?
- In a “Combined” sewer system, a single pipe conveys both SANITARY flow and rainwater.
- In a “Separated” sewer system, two different pipes are used: one for the SANITARY flow and different pipe for rainwater.
When it rains, combined sewers are sometimes overwhelmed and cannot hold all of the rainwater and raw sewage that is trying to flow through the pipes. The combined sewer then “overflows” excess raw sewage and rainwater to nearby waterways. In Henderson, our combined sewers overflow to Canoe Creek and to the Ohio River.
Click on the Combined sewer system image below to view a Flash animation of how that kind of sewer system functions. In the animation, click on both the “Dry” tab and the “Wet” tab to see how a Combined sewer system transitions between different weather conditions. The animation will open in a new browser window.
Click on the Separated sewer system image below to view a Flash animation of how that kind of sewer system functions. In the animation, click on both the “Dry” tab and the “Wet” tab to see how a Separated sewer system transitions between different weather conditions. The animation will open in a new browser window.
Henderson has 16 permitted CSO discharge points, but only 11 of them are “active”. Five of the discharge points have been permanently sealed or completely removed from the system. In addition, the first permitted discharge point is designated as the place where our treated water is returned to the Ohio River.
The discharge points are permitted by KPDES, the Kentucky Pollutant Discharge Elimination System.
Click on the link to each discharge point to see photos and detailed information about that location, including photos of each outfall location, receiving body of overflow discharges, size of discharge pipe or conduit, and historical discharge summaries.
KPDES 001 – North Wastewater Treatment Plant (NOT a CSO point)
- KPDES 002 – Janalee Drive Pump Station
- KPDES 003 – Ragan Street
- KPDES 004 – Jackson Street
- KPDES 005 – Towles Street
- KPDES 006 – Clay Street Diversion
- KPDES 007 – Powell Street
- KPDES 008 – Washington Street
- KPDES 009 – First Street
- KPDES 010 – Second Street
- KPDES 011 – Fourth Street (CLOSED)
- KPDES 012 – Fifth Street (CLOSED)
- KPDES 013 – Eighth Street (CLOSED)
- KPDES 014 – Second Street Pump Station
- KPDES 015 – Third Street Basin
- KPDES 016 – Cooper Park Pump Station (CLOSED)
- KPDES 017 – Outer Fifth Street (CLOSED)
An overview of Henderson’s CSO area is shown below.
Henderson’s Combined Sewer System
The oldest sewer lines in the City of Henderson were constructed between 1880 and 1960. Most of these sewer lines were built as a combined sewer system. These combined sewers were designed to collect both sanitary sewage and stormwater runoff in the same pipe. During periods of heavy rainfall, the capacity of the combined sewer system is often exceeded due to large amounts of stormwater runoff that enters the combined sewers. There are several combined sewer overflows (CSOs) in the sewer system that discharge this mixture of wastewater and stormwater into receiving waters of the City during heavy rainfall events. Specifically, these outfalls are located along the Ohio River and on Canoe Creek at Second Street.
Henderson Water Utility (HWU) has completed many sewer separation projects over the past decade to eliminate areas of the combined sewer system. Additional projects are planned to continue eliminating areas of the combined sewer system and CSOs. HWU has posted CSO warning signs at all locations where overflows occur during these periods of heavy rainfall. The receiving streams can become polluted during and after rain events due to high bacteria levels found in combined sewage. Residents should be aware of this potential health hazard in the Ohio River and Canoe Creek during and after periods of heavy rainfall.
Rainfall amounts and Ohio River elevations can be found at the following link from USGS, the U.S. Geological Survey:
USGS 03322190 OHIO RIVER AT HENDERSON, KY
(River elevation and rainfall amounts)
For more information on CSOs and their effect on the water quality of the Ohio River and Canoe Creek, please call HWU at (270) 826-2824.