THE Madras High Court on Wednesday issued notices to the State Government on a public interest writ petition that sought to put the administration on the mat for releasing untreated sewage water directly or indirectly into the city's waterways. Petitioner V Ravichandran, founder-chairman of an NGO, Cit izens Guardians, alleged that the government was not implementing the Chennai City River Conservation Project in its letter and spirit. A vacation bench comprising justices G Rajasuria and M Sathyanarayanan ordered notice to the authorities concerned, returnable in four weeks.