sewage

For London this is probably now a bigger issue than sewage inputs from sewage treatment works.

Researchers have achieved a breakthrough in improving the efficiency of an electrochemical reaction that produces hydrogen peroxide -- a vital chemical for industrial applications such as disinfection, bleaching, and sewage treatment.

City leaders are investing in the facility while also planning a much larger effort to turn sewage into purified drinking water.

The company admitted a series of failures which led to untreated sewage being discharged into the rivers in Wiltshire and North Somerset in 2018.

Testing by chemists has determined the balls were the result of a sewage spill, though their exact origin remains unknown.