In the February 2012 issue of Water Environment and Technology Magazine is an article titled “A solution for clogging pumps”, by Mike Gerszewski and Jim Fischer. If you are looking for an answer to your high-heeled wooden dancing shoe problems, it’s not very helpful. If you are looking for a case study in the costs related to plugging lift station pumps, it’s definitely worth a read.
The Village of Hartland, Wisconsin had frequent problems with debris clogging its sewage lift stations. Three or four times per week at random times during the day workers were called to unclog a pump. A staff of six operators was kept on hand to respond to those calls. Unclogging each pump took at least four man-hours and was obviously not a fun task.
Ultimately the village discovered a new style of pump that could handle the debris without clogging. As expected, the solution eliminated the clogging problem and the associated maintenance costs. An added, unexpected cost savings was a 60% average reduction in energy usage. Debris getting stuck in the impeller had dramatically reduced the pumping efficiency in the original lift stations.
The pump selection process considers many factors. Debris in the material to be moved must also be one of them. A lift station that cannot handle everything it encounters is not truly operating at its “best efficiency point.”