Articles & Case Studies

Madison County gets a lift

Posted: Wednesday 9th September 2020

“I used to dread coming here”, said Mitch Puckett, Director of the City’s Water & Sewer Department.

And no wonder. Despite the installation of two pumps that were sold as being able to cope with typical lift station debris, the chore of having to unblock rags became an all too regular occurrence – in less than 12 months from when they were installed.

Then, there was the grease.

‘Layer of grease more than seven feet thick’

Even with all the grease traps that are in use at food establishments as per code enforcements, it seems that almost every town in America has at least one lift station that its sewer department dreads – and at Madisonville, the layer of grease – for all the hard work to keep it at bay – would at times build up to more than seven feet thick!

“It was unreal”, commented Kevin Story, Director of Public Works for the City of Madisonville.

“It was also ridiculous that so soon after the installation, the problems at this, our most recently built lift station, meant Mitch and I having to spend so much time trying to put it right. Pulling these pumps out isn’t easy – and as any small water and sewer team will tell you, we already have more than enough to do with taking care of the City. Coming back time and time again to Lift Station #8 had to change”.

Kevin and Mitch acknowledge that the opening of a major new retailer just across the street – complete with 40 restrooms - was certainly going to create challenges for the existing sewer system. Together with grease and rags that inevitably find their way into the sewer from Madisonville’s near 4,500 population, the only remedy at times was to bring in the vac truck. Kevin had campaigned hard for the city to invest in its own vehicle – whereas others face a cost of up to $5,000 each time a vac truck is called upon. Chemicals can also help a beleaguered lift station – but while they provide some respite – inevitably, the grease problem always returns – as does an annual chemical bill – also around $5,000.

For this tough application at Lift Station #8 (of a total of 12 in the city), the failure of the two duty pumps lay in the design of the impellers, which soon became dull and unable to efficiently cut debris. The rags and trash included everything from t-shirts to towels and underwear to mop-heads, to hygiene products – plus the almost never-ending intake of grease.

As Madisonville’s very experienced (27 years in the industry) Public Works Director, you won’t find Kevin Story sitting behind a desk very often. He’s out and about in the City making sure things are right. The exception is when he’s at a short school, always learning. He and his dependable colleague Mitch Puckett attain valuable qualifications through the Texas Commission on Environmental Quality – and keeping up to date on the right equipment.

Frustrated (to put it mildly) with the trials and tribulations of his notorious Lift Station #8, Kevin discussed potential solutions with Waco-based Smith Pump Company. Based on previous successful installations, including the complete turnaround of a very onerous lift station at Llano County, Texas, it was decided to try an AeriGator Chopper Pump from the company that invented it seventy years ago 1950, Landia.

‘Protects the existing two duty pumps that can’t cope with heavy solids’

Designed with a hardened-steel knife system that stops large solids from entering the pump’s casing, the Landia Chopper Pump was an instant success. In fact, it now effectively protects the existing two duty pumps that can’t cope with heavy solids, so that the City of Madisonville does not have to eat into its budget to replace them. Furthermore, to suit the variances in lift station scum, the Landia Chopper Pump is fitted with the addition of a venturi nozzle to create the AeriGator model. For lift stations that are close to homes, the AeriGator has been particularly effective at reducing odors, which, for example, was very important in Llano County.

“We were satisfied with the Landia AeriGator from day-one”, said Kevin Story.

“It’s a complete 180-degree difference from what we had. Before Landia, Mitch and I were having to take the volute covers off the duty pumps and try to re-shim everything as best we could to get the impeller close to the wear-plate – but try as we did, the volume of grease and debris would find a way of backing up and oozing up and over the lift station walls. My team worked very hard to ensure that this could only happen at a lift station or a manhole, rather than a home or a business, but the grease was terrible. Hard to believe that we had it seven feet thick here (!), but now at last, that’s a thing of the past”.

He continued: “Pumps aren’t cheap. It was a worry that the float would sit on top of all the grease, leaving the duty pumps running to a possible expensive burn out. We don’t want to be using up funds on replacements when the City needs money that can be spent elsewhere on services. Grease damages pumps and we also don’t want to be losing out on some of our capacity because of it. Now, thanks to Landia, we look down on clear water – and no longer have to dread going to this particular lift station. And because things are so much better, it also helps our other lift stations”.

‘We thought about the future’

Kevin Story concluded: “Long after we’re gone, I want people here to see that we cared about looking after the City – and that we thought about the future, so I am very pleased that we solved the issues of lift station number 8 for the long-term”.

He certainly has a point. Last year, Texas was the American state with the largest growth in population. The need for robust, long-lasting pumps is essential.

Madisonville is not alone in having pumps that either simply don’t have enough horsepower for the job or don’t have the proper macerating system to handle rags. Standard duty pump specifications are no longer enough for the ‘dreaded’ lift stations. Likewise, Landia recommends that Constant Torque VFDs (variable frequency drives) also be included in the next wave of future lift station designs - otherwise rags sitting at the suction of the pump immediately upon start-up cannot be properly macerated. This can cause another problematical, messy, time-consuming and costly pump pull-out. Kevin Story will tell you that it is just better to avoid that if possible.




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July 2020

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