Oregon will install, operate and monitor temporary flow meters at five locations in the sanitary sewer system to reduce or eliminate excessive storm water from getting into the wastewater collection system.

Flow monitoring, video detection, and smoke testing will help identify inflow and infiltration (I&I) sources.

Some residents, in neighborhoods off Seaman Road, complained about flooding in their homes following heavy rainfall on July 3. They told council at a meeting last month that they were overwhelmed with cleaning bills and threats of cancelled homeowners insurance policies.

Some residents on Chardonnay Lane, in particular, had backed up sewage in their homes.

“Flow monitoring is really the first step in trying to get a good handle on inflow and infiltration reduction,” said Public Service Director Paul Roman at a council meeting last Monday.

The flow meters, which look like “giant rings,” said Roman, will be installed into the sanitary sewer interceptors for a period of four months.

The sanitary sewer locations where the meters will be installed include south of Brown Road, which will help get a handle on I&I coming from the northwest sewer district, a Seaman Road interceptor just west of Lallendorf Road, the new Seaman Road interceptor east of Lallendorf Road, and on Lallendorf Road, just before Seaman Road. Another one will be installed in the north Oregon sanitary across Wynn Road from the Eagles Landing area.

Flow monitoring is considered the first phase in an I&I reduction program to help identify and prioritize areas in the wastewater collection system that have the greatest amount of I&I.

“Those are the areas you really want to do more in-depth I&I investigation work, such as smoke testing and videotaping of sewers. There are a lot of things that can be done with this data. The hope is that we put them out there for about four months, and we get a couple heavy rain amounts in that time. If we don’t, we would extend the time we have them out there. Hopefully, we will get those rain events in that amount of time. If we don’t, I’ll be coming back to council for an extension so we can get that data,” said Roman.

Council approved a contract with Jones & Henry Engineers, Ltd., Toledo, to provide engineering services to install the flow meters for $23,600 for four months.

“They are very knowledgeable with this work. They have done a lot of flow monitoring for a lot of cities, and been involved in a lot of I&I reduction programs for a lot of cities,” Roman said of Jones & Henry. “I think they will do a good job getting them installed quickly.”

The city’s first task is to meter flows from the major branches in the sanitary sewer system and compare the maximum to average flows from the various major branches. It will help identify and prioritize areas in the city that have the greatest amount of I&I and the most likely areas where more detailed investigations should be done. It will also help to determine if peak wet weather flows exceed the capacity of the various interceptors.

A final report will be prepared to compare metered flows from the five study areas considering average dry weather flow, wet weather flow, and rainfall occurrence and intensity.

Pump flow data from the Reno Beach-Howard Farms area are available from Lucas County, said Roman.

“But from the northwest sewer district, it comes by gravity. I think the idea is to go to them with this data and discuss I&I reduction with them and see all the steps they are taking as well as what steps we might take,” said Roman.

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