Mishawaka CSO News

Combined Sewer Overflow Update March 2011

Dear Friends and Neighbors:

In these times of economic uncertainty, getting the most out of every dollar is more important than ever. Just like individuals, cities face expenses that cannot be avoided. One such expense is the federal requirement to address combined sewer overflows. Combined sewer systems carry storm water and raw sewage in the same pipes. Combined sewer systems were built prior to the 1950’s, and can discharge untreated sewage and stormwater into the river at structures called combined sewer overflows (CSOs) when there are heavy rains. These overflow points protect houses from basement flooding and prevent sewage from backing up onto streets and yards, and were considered a cost effective way of dealing with the overflow of storm waters.

Today, however, the systems do not meet with standards for environmental sustainability. There are 770 CSO communities in the United States which serve about 40 million people. Mishawaka is one of more that 100 Indiana communities with combined sewers and CSOs. As a result of the negative environmental impacts they create, Federal law requires all cities with combined sewers to develop long-term control plans to reduce or eliminate CSOs.

The elimination of combined sewer overflows is difficult and expensive. It is not simply a matter of fixing something that is broken. Correcting CSOs requires redesigning large parts of our sewer system, including expanding the wastewater treatment plant, increasing sewer sizes, building storage tanks and tunnels, and building new separate storm and sanitary sewers.

The water quality in the Saint Joseph River is better than at any time in our lifetimes. The reduction of CSO to the river during wet weather is required by federal law and continues to be one of the City’s top priorities. Since 1990 Mishawaka has reduced annual CSO volume approximately 86% from 300 million gallons per year to less than 50 million. These significant reductions have been achieved by a combination of treatment plant expansions, sewer separation projects, and sewer system capacity upgrades. Mishawaka has developed a long term plan to address the remaining combined sewer overflows.

During 2010 the City continued negotiation with EPA, IDEM, and the Department of Justice over language in the Long Term Control Plan (LTCP) consent decree. The City submitted its final draft in October for review by the agencies. The proposed plan will vastly reduce the occurrence of CSO from the current 50 overflows per year to zero overflows in years with typical rainfall.

Funding the LTCP will require periodic rate increases. A 2008 cost of service study recommended adjustments to the City’s sewer rate structure to ensure fair allocation of cost among the different user classes. The first rate increase was implemented in 2009 and the second in 2010. A third rate increase occurred in 2011. These rate adjustments will provide revenue to fund approximately $50 million of LTCP improvements.

Final approval of the LTCP from the EPA should occur in 2011. The plan is estimated to cost between $140 and $160 million and the City is requesting a 20 year implementation schedule. Consistent with EPA policy, once the LTCP is approved it will be enforced in a federal consent decree. The decree will require implementation of the Long Term Control Plan or the City will face penalties.

Although Mishawaka’s CSO control plan has not been formally approved, the City is proactively addressing the problem. In 2010 the Milburn Blvd. area underwent extensive sewer separation work which removes rainwater runoff from the sanitary sewer system. Getting stormwater out of the sanitary sewer system reduces the frequency and volume of combined sewer overflows.

In December a $37 million Sewage Works revenue bond was sold to complete the sewer improvements in the Milburn Blvd. area and to fund the next phases of CSO long term control measures.


Combined Sewer Overflow (CSO) Update October 2008

The reduction of CSO that flows into the river during wet weather continues to be one of the City’s top priorities. The expansion of the wastewater treatment plant reduced our existing CSO volume by 60%, but much work remains. In 1990 there were approximately 350 million gallons of CSO that flowed into the river. A combination of sewer separation projects and treatment plant upgrades has reduced this annual volume by over 300 million gallons per year.

During 2008 the City of Mishawaka continued negotiation with the EPA, the Indiana Department of Environmental Management, and the Department of Justice over its CSO Long Term Control Plan (LTCP). The City is preparing to submit its final draft of the LTCP to the above mentioned agencies by the end of October. The plan will vastly reduce the occurrence of CSO, from the current 50 overflows per year to less than one overflow per year. This plan takes into account the expansion of the treatment plant and future modifications to the collection system that include increasing existing sewer capacities, additional sewer separation, and storage in underground basins and tunnels. During wet weather these storage facilities will hold back excess flows until the rain subsides. These stored flows will then be put back into the sewer system for treatment at the wastewater plant.

Our goal was to have an approved LTCP by the end of 2008. Once the LTCP is approved, the Department of Justice will incorporate it into a federal consent decree, and mandate the City of Mishawaka to comply to this standard. Because of the high cost of further CSO reductions, it is expected that the implementation of the LTCP will take 20 years to complete. The LTCP implementation schedule will be dictated by our ability to pay for the needed improvements. The cost for meeting the future CSO reduction requirements could exceed $140 million.

The City of Mishawaka knows its future relies on a clean and healthy St. Joseph River. The Mishawaka Riverwalk, now in its final phases of construction, is a cornerstone of the city’s economic development efforts. When completed in 2009, the Riverwalk will connect downtown Mishawaka to many neighborhoods and parks along the river. Protecting the water quality in the river makes good economic and environmental sense. Mishawaka’s economy also benefits from hundreds of sport fishermen who visit each year to catch migratory salmon and trout. Recent surveys of fish populations in the river have found over 80 species of fish in the Saint Joseph River. Because of our continuing efforts to improve water quality the fishing is so good that the Department of natural Resources has nicknamed the city “Fishawaka”. Visit the Mishawaka Utilities web site and click on CSO INFO to learn more about CSOs and projects we are implementing to reduce combined sewer overflows.

Combined Sewer Overflow Update 2007

Treatment of wastewater isn’t something we think much about. As long as the sink drains and the toilet flushes, we give it no further thought. However, wastewater treatment is one of the vital services provided by our city. The British Medical Journal recently asked experts to list the greatest medical advance from the past 150 years. The final outcome of the survey might shock you. The winner was sanitation – including wastewater treatment and clean drinking water. Mishawaka is proud to provide both to our citizens.

We completed the upgrade and expansion of our wastewater treatment plant project which began in late 2004, located in the former Lincoln Park. The expansion was needed to provide treatment capacity for our growing community and to reduce combined sewer overflows (CSOs) into the river during large rainstorms. The average capacity of the treatment plant is being increased from 12 million gallons per day to 20 million gallons. The peak capacity, to treat increased flow during wet weather and reduce CSOs, increased from 24 to 42 mgd. Combined sewers carry sanitary sewage and storm water in the same pipes. Combined sewers were built in the first half of the last century; the practice is no longer allowed. There are still over 90 combined sewer communities in Indiana and over 900 nationwide.

During large rainstorms, there is not enough capacity in the combined sewers and treatment plant to handle all the flow. When this happens, excess flow is discharged to the river from combined sewer overflow points (CSOs). These relief points are necessary to prevent basement back-ups and street flooding. The wastewater plant expansion reduced the current combined sewer overflow volume by about 50%. Since 1990 Mishawaka has reduced CSO discharges by over 85% by sewer separation projects and plant expansions. All new sewer construction is separated. Sanitary sewers send sewage to the wastewater treatment plant; storm sewers send storm water to the river. Still, about 30% of Mishawaka’s sewer system remains combined.

EPA is mandating Mishawaka and all other CSO communities to address our remaining overflows. We are developing a long term control plan to reduce overflows, through further sewer separation, upgrade of sewer capacity, and building underground storage tanks to hold wet weather flow until it can be sent to the treatment plant for processing. The positive impact of the changes we have already made will be felt for generations; but, there is still much to do so that we will have capacity for continued growth and development, and the reduction in CSO volume as we continue our progress in protecting the Saint Joseph River.