A form of water treatment in which water is pumped backwards through the filter media, sometimes with intermittent use of compressed air.(noun)
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Use "backwashing" in a sentence
"Downtown Houston probably high enough to not get a lot of this backwashing water so to speak coming up the ship channel, but, Anderson, there could be 10 inches of rainfall there in Harris County, and that could cause flooding with freshwater."
"Conventional filter backwashing as applied in rapid sand filtration is not possible since the filter bed of roughing filters cannot be fluidised."
"All production wells must be developed to remove drilling cuttings and mud which has migrated into the well wall and into the aquifer during drilling and to remove fine silt and sand from the aquifer around the screen to produce a coarser and more uniform gravel envelope around the production well; this may be accomplished by a variety of procedures including pumping, surging, injection of compressed air and backwashing."