CSO Notification System

The EPA has mandated that the City of Clyde address the issue of CSO’s within the community since 2004. This appears to be a continually evolving program with the EPA. In 2005 the City of Clyde submitted the Long Term Control Plan (LTCP) for the Combined Sewer System (CSS). Over the intervening years (to present day) the city has separated several storm/sanitary sewer lines in the city and constructed a 1,000,000 gallon basin to capture overflowed wastewater before it enters Raccoon Creek.

The City of Clyde has a Combined Sewer System (CSS). It was originally designed to carry Sanitary Wastewater (consisting of domestic sewage, commercial and industrial wastewater) and storm water (surface drainage from rainfall and snow melt) in a single pipe to a treatment facility. During dry weather CSS's convey Sanitary Wastewater. In periods of rainfall or snowmelt, total wastewater flow may exceed the capacity of the CSS's. When this occurs, the CSS was designed to overflow directly to surface water bodies. In Clyde there were CSO’s that flowed into Raccoon Creek. These over flows, called combined sewer overflows (CSO’s) may have been a source of water pollution in our community.

As part of the sanitary/storm sewer separation projects here, these CSO’s have been permanently removed, closed and/or sealed. This created a hydraulic overload on the entire collection and treatment systems. Due to the need to alleviate hydraulic stress on these systems a CSO screening facility along with flow redirection modifications were constructed. When it becomes necessary, the CSO facility provides the collection system with hydraulic relief while at the same time providing protection to the community and environment by screening out potentially harmful debris. Because CSOs contain untreated domestic, commercial and industrial wastes, as well as surface runoff, many different types of contaminants may be present: pathogens, suspended solids, nutrients, toxins, and floatable matter. CSO's have been shown to be a major contributor to use impairment and aesthetic degradation of receiving surface waters (Raccoon Creek), and may contribute to adverse health effects when the population has contacts with this water after a period of overflow or discharge.

It is for this reason that the EPA mandated, and the City of Clyde has complied, that the CSS be separated and sealed to eliminate any unregulated overflow discharges to Raccoon Creek.

Since 2004, as the City rebuilds existing streets and new streets are added, many of the storm and sanitary sewer systems are separated. The storm water will flow to the Creek and the Sanitary wastewater will flow to the treatment plant.

With the knowledge that this action would hydraulically overload the sewers the EPA, in 2004, approved the construction and installation of one CSO screening device located on the main sewer line entering the Wastewater Treatment Plant. This screening device will remove debris and solid material larger than a kernel of corn from any CSO discharge to Raccoon Creek. Additionally, in 2015, the EPA approved of the construction of a Storm Water Flow Equalization Basin that will capture the first 1,000,000 gallons of the CSO screened wastewater before discharging to Raccoon Creek. One of the main objectives of Clyde's LTCP is to ensure that no more than four (4) CSO events occur per year.