From Flo-Tote to Flo-Dar at Chesterfield County Sewer Flow Monitoring Freedom

Recently ranked one of the fastest growing counties in the nation, Chesterfield County, Virginia, is bound by the James and Appomattox rivers and is known for its miles of historic picturesque landscapes. Residents and governmental agencies alike realize the importance of their natural resources and have set forth plans to keep it that way for future generations. Their dedication has garnered them multiple awards and esteemed recognition amongst both governmental agencies as well as major industry associations, including the Environmental Protection Agency (EPA) and the Association of Metropolitan Sewerage Agencies (AMSA). AMSA spokesperson states, 'They are among the best-operated, most efficient water systems in the nation and are a credit to their communities.ä Additionally, the County is one of two water and wastewater utilities in the nation to earn a AAA bond rating for their well-managed financial operations.

A major force within the Countyâs Utilities Department is their steadfast commitment to utilize only innovative technology to maintain their water and wastewater systems. Providing outstanding wastewater services to over 75,800 customers in their service area, they are also responsible for the maintenance and operation of 23 pump stations, 1,690 miles of sewer line and two wastewater treatment plants including the Proctors Creek Wastewater Treatment Plant and the Falling Creek Wastewater Treatment Plant. Together the two plants treat 21.87 million gallons of wastewater per day (MGD) with a total combined capacity of 37.10 MGD.

For over 20 years the County has utilized Marsh-McBirney Flo-Tote Open Channel Flowmeters to capture flow data necessary for their continual Inflow and Infiltration (I&I) studies as well as long-term monitoring projects. Wayne Riggins, Utilities Supervisor, states, 'When I joined the county 19 years ago they were already using the Flo-Tote meters. We have 15 Flo-Totes today and we are still using the meters in various locations. The person who had my position prior to me, Kenny Swann, had budgeted for five flowmeters from Marsh-McBirney. The meters used a new technology and he thought they would be a good fit.ä

Kenny Swann adds, 'I was looking for new flowmeters for our I&I monitoring work. We saw that Marsh-McBirneyâs new meter, the Flo-Dar, had a non-contact sensor. The non-contact nature would cut down on the number of times we actually have to go out and clean submerged sensors due to fouling or sedimentation.ä

Since its introduction in 1996, thousands of Flo-Dar Radar Velocity/Area meters have been installed worldwide to accurately monitor open channel flows. Marsh-McBirneyâs new generation of flowmeters utilizes highly accurate radar technology to remotely monitor open channel flows. Sensor fouling is totally eliminated savings thousands of dollars at each monitoring site usually required for sensor maintenance and confined space entry when using submerged style sensors. The Flo-Dar sensor can easily be removed or re-installed from street level. Additional benefits include field replaceable/interchangeable sensors and monitors ensuring no lost data in the field, especially during critical monitoring periods. Sensors can be installed with either a permanent mount (affixed to wall) or a portable mount (jack-bar tension rod) dependent upon the specific application.

Flo-Dar applications that challenge traditional flowmeters include:

Both portable and temporary mounts were purchased for use in their monitoring program. Currently, a manhole located nearby a railroad track was being monitored with one of the Flo-Dar meters. Due to the vibration from passing trains the permanent mount was installed and has been working flawlessly.

One of Chesterfield County's Flo-Dar sensors shown installed above
the sewer flow (left) and the Flo-Logger and Pocket PC (at right).

Two County field crews responsible for data collection are using Marsh-McBirneyâs Flo-Ware FX software installed on their Pocket PCâs to retrieve data from the meters. Flo-Ware FX is a flowmeter data management tool that operates on the Pocket PC operating system. The convenient hand-held Pocket PC features a touch screen, zero boot-up time, and extended battery life (up to 20 hours of use), making this system ideal for field use versus cumbersome lap-top computers. In the office, the Pocket PC automatically synchronizes with a desktop PC allowing the seamless transfer of files to and from your Pocket PC to desktop PC for data analysis and reporting.

The importance of top-notch, award winning water and wastewater practices displayed by Chesterfield Countyâs Utilities Department will serve their social and economic future well. Their continued use of state-of-the-art technologies, like those used in the Flo-Dar Flowmeter, will ensure that their commitment thrives while providing safe, efficient and cost-effective flow monitoring practices.