In a classic case of unintended consequences, flushable wipes – a truly modern, useful and popular convenience – are wreaking havoc with sewer systems in the U.S. and across the world.
The problem is straightforward and intrinsically linked to the wipes’ design: they’re tough and durable, which is great for users but not great for the typical lift station pumps used in sewer systems. Since the wipes don’t deteriorate, they get stuck in the pumps, causing pump failures and forcing untreated sewage back into homes and businesses.
Although the result – sewage backups due to pump failure – is the same, the issues vary depending on what type of lift station pump is used:
Centrifugal pumps: Failure results when the wipes bind up the pump impellers.
Chopper pumps: Failure results because the blades at the end of the pump impellers shred (rather than chop) the wipes, and the shreds bind up the impellers or starve the suction/inlet of the pump.
Regardless of which of these pumps is used, the consequences for municipalities and other sewer operators stretch far beyond sewage backups and include:
- Labor and materials costs for replacing the pumps
- Postponement of other important work due to staff being diverted to replace or fix the pumps
- The cost of repairing ancillary damage to the pumping facilities caused by the failure
Compounding all of this is the remote location of many of the lift stations where the pumps are used. The time it takes to get to the stations, combined with the difficulties of working remotely, simply adds to the overall costs related to these pump failures. Inevitably, these costs are passed on to the community through higher user fees or increased taxes.
With few technical solutions available, sewer system operators have resorted to educating consumers, suing wipe manufacturers and instituting laws regulating flushable wipes. In the end, flushable wipes have proven to be a truly inconvenient modern convenience.
- Posted by Madelyn Vetter
- On May 8, 2017