Untreated wastewater enters a body of water either by accident or by system design. An accidental release, or spill, is caused by human error or equipment failure. A designed release is due to the construction of the wastewater capture and treatment system and is permitted by the governing authority. Regardless of if by design or by accident, untreated wastewater entering a natural body of water is detrimental. Sewer systems designed to allow for releases of untreated wastewater are old technology and extremely harmful to the environment but still found in cities across Georgia (including Albany and Columbus) and the ACF Basin.
A Combined Sewer System (CSO) captures stormwater (rain) from storm drains and wastewater (sewage) from homes and businesses in the same pipe. Under dry conditions the pipe only contains wastewater and transports it to the treatment plant where it is then treated and released into a natural body of water as treated wastewater. The contents of this treated wastewater are controlled by the treatment plant's NPDES permit and any violation of this permit must be self-reported to the governing body.
Problems with CSO systems arise under wet conditions. Impervious surfaces such as sidewalks, parking lots, and paved streets cause stormwater to rapidly flow into storm drains and quickly fill the pipes of the CSO system with a large volume of water. This stormwater is already carrying a variety of harmful pollutants (trash, motor oil, animal feces, etc) from flowing across the urban landscape and upon entering the CSO system it is combined with whatever wastewater is already being collected from homes and business.
The sudden increase in volume of water is more than the sewage treatment plant can process so overflows, or outfalls, are built into the system to allow the excess stormwater (now intermixed with wastewater) to discharge from the combined system into the river. Control devices are built into the system to prevent solid matter (trash, feces, toilet paper) from exiting into the river but these devices are not fool proof. Regardless of wether or not solid matter escapes into the river, water discharged from a CSO outfall is heavily polluted.
The old saying of "The solution to pollution is dilution." is commonly used to justify CSO systems. Advocates for CSO's will say the river is already carrying enough water (due to the rain) to dilute the discharged water to a level it causes no measurable harm. Measurable being the key word. Like the city of Albany, the CSO outfalls of Columbus are located along the city's riverfront and as both cities shift their focus and base the rejuvenation of downtown on attraction to their respective rivers, more people are being impacted by these outdated sewer systems, adding to the necessity of system improvement. Unfortunately, replacing a sewer system is an expensive affair and with neither city having hundreds of millions of dollars to spare, the can has been repeatedly kicked down the road, so to speak.
Sewer spills are also problematic but generally on a much smaller scale and recent spills in Albany have been quickly responded to, and repaired, by the city. We hate to see a spill and Flint Riverkeeper works with a team of volunteers and concerned citizens to always be on the lookout for issues and once a problem is found, we stay on it until repairs are made.
Both Flint Riverkeeper and Chattahoochee Riverkeeper are working with Albany and Columbus (respectively) to see improvements to the systems and eliminations of CSO's. This is a difficult and long process for all parties involved but a process FRk and CRk deem to be absolutely necessary to improve the health of the Flint and Chattahoochee and to protect the people who recreate in each river. Most recently, Flint Riverkeeper submitted
comments regarding the renewal of Albany's permits and Chattahoochee Riverkeeper has been active in the ongoing renewal process in Columbus.