When you start a remote pump, you expect to know right away whether it actually turned on. In the Genesee County Drain Commissioner Division of Water & Waste Services’ (GCDC-WWS) legacy radio polling system, that confirmation could take four to five minutes.
Across 180 remote water sites in mid-Michigan’s Genesee County, communication slowdowns and concentrator failures repeatedly cut off or delayed visibility to critical equipment. With delays measured in minutes and frequent communication dropouts, operators could not reliably fine-tune pumping stations. Short pump cycles often went completely unrecorded, and communication alarms became so common that distinguishing real failures from network noise grew increasingly difficult.
The Genesee County Drain Commissioner, Jeff Wright, Division of Water & Waste Services (GCDC-WWS) operates 180 remote sites across 600 square miles in the state of Michigan.
The Limits of Radio Polling
The GCDC-WWS operates drinking water distribution and wastewater collection systems across more than 600 square miles. Dozens of water and wastewater remote pump stations are spread throughout the county, each relying on consistent communication back to the central SCADA system.
For years, remote site communication depended on a multi-hop licensed radio network. Field sites transmitted over 200 MHz radios to local concentrator stations, which then forwarded data over 900 MHz links back to the central office. While the radios were solid line-of-sight systems, the architecture created built-in latency and multiple points where a single concentrator failure could disconnect numerous downstream sites at once.
Communication followed a traditional polling model. The master station requested data from concentrator sites, which in turn polled individual field locations before sending responses back up the same chain.
“You’d send a command and just wait,” says Terry Biederman, P.E., Assistant Director of Water for the GCDC-WWS. “This was an unacceptable situation. Communication failures were also so numerous that staff didn't know if they should respond and unnecessary overtime cost was increasing as a result.”
Even when functioning normally, the sequential polling process limited real-time control and visibility.
Rethinking Remote Sites
Communication delays were only part of the challenge. The existing approach depended on traditional PLC-based systems that needed dedicated controller hardware, separate communication equipment, costly programming software, and a SCADA platform with costly, per-seat licensing agreements.
Even small, unmanned, two-pump lift stations had to carry the weight of that full stack, creating capital and lifecycle costs that did not scale well across hundreds of diverse and geographically dispersed sites.
“A small lift station SCADA system could easily run $15,000 to $20,000 using the traditional approach,” Biederman explains. “For small sites, that just wasn’t cost effective.”
As the GCDC-WWS began upgrading aging remote sites and their SCADA systems, the team faced a choice: they could replace older hardware with newer versions of the same architecture, or they could shift and take advantage of newer technologies that addressed their problems directly.
Legacy systems in remote water and wastewater stations operated reliably with established controls, but using legacy communication methods made system-wide visibility difficult.
From Polling to Publishing
The GCDC-WWS began evaluating a different model built around Sparkplug® B MQTT publish/subscribe communication versus the legacy polling model.
“We knew from our experience, and from other utility examples, that MQTT was the way to go,” Biederman says.
Instead of waiting to be polled, Sparkplug B MQTT publish/subscribe architecture allows remote sites to publish data as changes occur. Because data is transmitted by exception instead of constant polling, bandwidth drops significantly, making cellular data plans practical at sites that previously relied on radio.
And since Sparkplug B MQTT uses a purely outbound, client-initiated connection model, there are no unsolicited inbound communications, making networking and firewall management much simpler, and reducing the attack surface.
SCADA Transition
Modernizing communications also meant modernizing the SCADA layer.
For years, the GCDC-WWS relied on iFIX®, a SCADA and HMI platform developed by GE Digital®, for visualization and historical data archiving. The system had served the county reliably, but it was built around traditional client/server polling architectures.
As the team evaluated Sparkplug B MQTT, they also began looking for a SCADA platform that supported publish/subscribe communication and reduced reliance on tightly coupled polling structures. That search led them to Ignition®, a modern SCADA and industrial development platform developed by Inductive Automation®.
“There’s a lot of legacy built into older SCADA systems,” Biederman says. “We wanted a platform architected for how we’re communicating now, not how we were communicating 20 years ago.”
Bringing Sparkplug B MQTT to the Edge
The other part of the problem was figuring out how to extend this new Sparkplug B MQTT communication model to all the remote sites.
“We had aging PLC infrastructure and a communications network that needed an update,” Biederman says. “Instead of replacing expensive PLCs at remote sites, we looked for a more cost-effective way to move forward.”
The GCDC-WWS selected Opto 22
groov EPIC (
Edge
Programmable
Industrial
Controller) processors for larger water and sewer pumping stations, where control and I/O could run locally while publishing data via Sparkplug B MQTT. Smaller sewer pumping stations and sites like meter-pits (underground enclosures protecting water meters) were outfitted with Opto 22
groov RIO edge I/O devices to modernize communications first, with plans to expand I/O as sites are upgraded.
“Ignition Edge® is built in, so we get Sparkplug B MQTT publishing out of the box,” Biederman explains. “It also lets us connect downstream to legacy PLCs over OPC UA® and bring that data into the same architecture.”
Cost was equally important. A traditional small lift station could approach $15,000 to $20,000 under the previous model. A
groov RIO with a cellular modem could be deployed for under $2,000, making SCADA visibility realistic at sites that previously had none.