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Completed and Ongoing Work in Oregon
The City of Oregon has started work associated with the I/I Reduction Program.  Here are some of the completed and ongoing projects associated with reducing I/I impacts:

GPS/GIS Sewer Network and Manhole Inspection/Maintenance

Beginning in 2007, the Department of Public Service started to inspect and tag sanitary and storm sewer manhole locations with a Geographic Positioning System (GPS).  These locations were entered into the City’s Geographic Information System (GIS) database.  Any faulty sanitary manholes or leaky sanitary manhole covers were noted and were added to a list for correction.  To date, the City has inspected and GPS collected over 4,500 structures in the sewer network.  Corrections have been made on over 300 manholes.  Typical work includes raising low-lying manholes, changing manhole lids with holes to solid lids, replacing broken manhole castings, cleaning plugged manholes, and bolting lids shut to prevent inflow.  This work is ongoing. 

Closed Circuit Television (CCTV) Sewer Inspection

The Street Department has been videoing sanitary sewers checking for faulty and/or deteriorated pipes, pipe blockages, and broken lateral connections to homes.  This work is part of an ongoing sewer maintenance program, required by the Ohio EPA.            

Flow Monitoring and Rain Data

Jones and Henry Engineers Ltd. was hired by the City to perform sanitary sewer flow monitoring
services during the fall of 2008 and spring/summer of 2009.  Flow monitors were placed into the sanitary sewers in various locations and wet weather flows were compared with dry weather flows.  Areas where the flows increased the most during wet weather are targets to reduce I/I. 
 
Figure 2 from the Jones and Henry final report shows the effects of wet weather on the WWTP.  This graph combines both the rain gauge data as well as the WWTP effluent (treated water discharging from the plant) to show how much storm water actually flows into plant.  This storm water flow is then unnecessarily treated as wastewater at a high cost. 

 Jones and Henry, Final Flow Monitoring Report, Figure 2

The red and blue bars are the rain data in inches per day from both the Willow Cemetery and the Municipal Complex rain gauges. The pink line on the graph is the WWTP effluent leaving the plant.  Immediately after rain events, the WWTP effluent skyrockets to levels far above the normal base flow of 4.0 million gallons per day(MGD).  In the case of the mid April 2009 rain event (1.6 inches in 24 hours) the flow rose to over 21 MGD, which is 5 times the normal base flow seen at the plant.  That’s over 17 MGD in excess flow that the WWTP had to treat due to the rain event.                 

 

To view the final Flow Monitoring Report Executive Summary, click the following link:

Jones and Henry Flow Monitoring Executive Summary

Sanitary Sewer Rehabilitation Project, Phase I

In the Fall of 2009, the City began a $740,000 sanitary sewer and manhole lining project that covered nearly 9,000 linear feet of sewer pipe and 51 sanitary sewer manholes.  This project was funded through the Ohio Public Works Commission. 

Rehabilitation work consisted of cleaning and videoing sanitary sewers and lining sewers that were leaking.  Infiltration target areas, such as sewers running underneath creeks, were chosen to be part of this project.  Also, 51 sanitary manholes were lined to prevent infiltration.  Based on current influent data, the normal dry weather flow seen at the WWTP was reduced by approximately 500,000 gallons per day (GPD) following this project.  This decrease was attributed to the elimination of groundwater infiltration into sewer pipes at creek crossings.  A Phase II is planned in the near future.  

Sanitary Sewer Rehabilitation Project, Phase II

The City of Oregon Sanitary Sewer Rehabilitation Project, Phase II consists of replacing existing sanitary sewer lines located within the right of way of Cresceus Road, Mambrino Road, and Grasser Street (between Pickle Roadn and Dearborn Avenue).  The project also includes sanitary sewer lining on Wheeling Street (between Navarre Avenue and Bleeker Street) and Pickle Road (between Grasser Street and Wheeling Street). 

The new sanitary sewer replacement has the same alignment as the existing santiary sewer within the public right of way.  A new sanitary sewer was installed on Fink Street, between Patchen Road and Cresceus Road, in order to reduce the depth of the sewer replacement on Cresceus Road.  All existing sanitary sewer lateral connections within the public right of way have also been replaced as part of the project. 

Existing storm sewers that were within the construction limits of the new sanitary sewers have also been replaced. 

In order to provide stormwater flood relief, a new storm sewer was installed within the right of way of Fink Street (from the dead end east of Mambrino Road to the dead end west of Patchen Road).  A new detention area was also created at the east end of Fink Street to provide temporary stormwater flood storage, and eventually drain properties between Grasser Street and Mambrino Road.

The City received $900,000.00 in grant/loan funding from the Ohio Public Works Commission (OPWC) and a low interest loan from the Ohio EPA Water Pollution Control Loan Fund to pay the estimated $2,337,289.00 project cost.  The said loans will be paid through the City's general income tax and there will be no new assessments to the property owners for the project. 

Construction has been completed for this project.   

System Evaluation and Capacity Assurance Plan (SECAP)

Civil engineering firm ARCADIS has been hired by the City to conduct a sanitary sewer system evaluation using computer modeling.  The OEPA is requiring this work to be completed by July 1, 2012.  The modeling will consist of simulating sewage flows in both the sanitary sewers as well as at the wastewater treatment plant and will help to identify any bottlenecks in the system.  Computer modeling of the sewer system will help the City plan for future improvement projects, including WWTP expansion.
 

Sanitary Sewer Manhole Rehabilitation Project, Phase I

This project consists of rehabilitating leaking/defective sanitary sewer manholes via various trenchless repair technologies, including lining and chemical grouting.  A total of 66 manholes were rehabilitated as part of this project.  These manholes were discovered and priority listed during GPS inspections of the structures.  This work was completed in Spring 2013.        

Storm Drainage Improvements

An aggressive storm drainage improvement program has been implemented along with I/I reduction.  Over 30,000 linear feet of creek/ditch bank have been debrushed and over 65 blockages have been removed to allow for better flows during rain events.  All three major drainage systems (Wolf Creek, Otter Creek, Amolsch/Driftmeyer Ditch) have been surveyed for storm water flow modeling and future drainage improvements.  Modeling helps identify flow constraints such as inadequately sized bridges and road crossings.  Preliminary design has also begun for relief storm sewers in these watersheds.
 

Sanitary Sewer Smoke Testing

The City of Oregon has completed sanitary sewer smoke testing in many parts of the city, concentrating in areas with sanitary sewers constructed before 1970.  Please refer to the Sanitary Sewer Smoke Testing web page for more information. 
 
 
 
 
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