City of Troy, MO

As with many cities and towns across the United States, aging infrastructure, including antiquated sewer systems, are posing inflow and infiltration issues. Such is the case for the City of Troy, Missouri. Nationwide, these deteriorating sewer systems are responsible for billions of gallons of untreated wastewater escaping the treatment system.

Established in 1819, the City of Troy has an estimated population of 11,000 and in recent years has experienced rapid growth. The City’s Public Works Department consists of 15 staff members that are responsible for the city owned utilities and infrastructure including storm water, sanitary sewers, and the water distribution systems as well as many other municipal tasks. The Water and Sewer Department is responsible for both the water and sewer system including the operation of their wastewater treatment plant. The 75-mile sewer system is comprised of clay tile, brick and concrete open channel sewers.

According to Jeff Burkemper, Assistant Public Works Superintendent for the City of Troy, “Unfortunately we have a lot of inflow and infiltration (I&I) into our system. Flow meters were needed to determine to what extent. We are doing an in-house study utilizing portable flow meters to find out which areas to concentrate on first. We are isolating these ‘bad spots’ and then determining what we can do to remedy these problems.”

In 2006, the City made a decision to rent Hach’s Marsh-McBirney Flo-Dar flow meters for a short term I&I study. The meters performed well and a decision was made to purchase two portable Flo-Dar meters for their continued studies.

The Flo-Dar Area/Velocity Radar Flow Meter provides a revolutionary approach to open channel flow monitoring. Flo-Dar combines advanced Digital Doppler Radar velocity sensing technology with ultrasonic pulse echo depth sensing to remotely measure open channel flow.

“We can train people to install, move the units around quickly, and use the Flo-Ware software and they are up to speed in no time.” Jeff Burkemper, Assistant Public Works Superintendent - City of Troy, MO

Combined with the Flo-Logger, users have a portable solution for flow their measurement needs. Flo-Dar provides the user with highly accurate flow measurements under a wide range of flows and site conditions. By measuring the velocity of the fluid from above, Flo-Dar eliminates accuracy problems inherent with submerged sensors including sensor disturbances, high solids content and distribution of reflectors. You can be assured that you will experience ‘no lost data’ with Flo-Dar’s non-contact, above the flow sensor that is unaffected by fouling due to debris and grease.

As the sensor is mounted above the flow, personnel have little or no contact with the flow during installation. Future sensor removal can be done without the need for confined space entry. The meter operates in the most difficult conditions including flows with high solids content, high temperature, shallow and caustic flows, large man-made channels, and high velocities up to 20 ft/s. During surcharge events Flo-Dar’s optional electromagnetic sensor will continue to provide uninterrupted and accurate flow monitoring through dry and wet weather flows without the need for routine sensor cleaning or maintenance. Additional Flo-Dar models are available for permanent monitoring and remote communications.

Meter selection at Troy was based on the elimination of down-hole site visits and meter reliability they experienced with their Flo-Dar rentals. Burkemper adds, “That we don’t have to enter some of these manholes is definitely a plus and the reason we continue to use them is reliability.” Another important factor in meter selection for the City was ‘meter friendliness’. Burkemper adds, “We can train people to install, move the units around quickly, and use the software and they are up to speed in no time.”

Flo-Dar Sensor utilized in I&I Study in Troy, Missouri The meters have been installed for over four years and according to Burkemper, “Are overall performing well. If our guys ever have a question or concern, the Hach Flow Meter Customer Service Group in Frederick, Maryland has been very helpful and appreciated.”

For the foreseeable future, the City of Troy will continue their I&I work to isolate problems within their sewer system utilizing the Flo-Dar meters. The accurate data gathered by the meters will enable them to determine the need for system upgrades and/or maintenance issues that require prioritization. Burkemper adds, “I think this is something that we will continue to do for a long time. Down the road, as budgets allow, we have plans to upgrade our current flow monitoring system.” Local Hach Flow Meter rep, Tim Curtis of Heartland Controls, looks forward to the City upgrading to Flo-Dar flow meters with wireless communication so they can see data in ‘real time’ and eliminate the need for visit sites to collect their flow data.