New Delhi, March 7 -- Nineteen of Delhi's 37 sewage treatment plants (STPs) are not meeting the treatment standards set by the Central Pollution Control Board (CPCB), posing a key challenge to the Yamuna clean-up due to the release of effluents with alarming levels of faecal coliform, experts and stakeholders said, citing the latest data shared by the Delhi Pollution Control Committee (DPCC)....