British engineers say they've launched a "sewer war" against a giant blob clogging London's sewers, reports the AP. Thames Water officials said Tuesday it will likely take three weeks to dissolve the outsize "fatberg." They caution against expecting quick results as the fatberg is 275 yards long and weighs as much as 11 double-decker buses, or roughly 143 tons, per the BBC.
Thames Water's Matt Rimmer says the fatberg—consisting of congealed wet wipes, diapers, fat, and oil—is "a total monster and taking a lot of manpower and machinery to remove as it's set hard." He said the task is "basically like trying to break up concrete." Eight workers are using high-powered jet hoses to break up the blob before sucking it out into tankers for disposal at a recycling site. (Smaller blobs previously appeared.)