The claim was made by Modi in a blog post he wrote Thursday, the day he filed his nomination as a candidate from the holy town.
Sibal joined issue, calling Modi "a man for whom distorting facts is a daily ritual", and challenged his claim that he would clean the Ganga in Varanasi the same way he cleaned the Sabarmati in Gujarat.
Sibal, a union minister in the outgoing government, circulated copies of a document containing pictures of a dirty Sabarmati sourced from a leading national daily. The document claimed "the Sabarmati is bedeviled with the same problems that afflict the Ganga."
The document further added, citing a report by the Central Pollution Control Board (CPCB), that "water quality of Sabarmati has very high pollutants, violating CPCB norms."
A study on Water Quality Monitoring Programme of the CPCB had earlier observed that the "National Water Quality Programme led by CPCB positions Sabarmati (Ahmedabad), Khari (Ahmedabad), and Amlakhadi (Ankaleshwar) as the most polluted rivers in India. Surprisingly, all these flow in Gujarat", according to the document's copy circulated by Sibal.
The CAG, in a report dated March 31, 2012, while reviewing the water policy of the Gujarat government said the Gujarat government "had not formulated any policy based on the local conditions for prevention of pollution of rivers, lakes and ground water," the document noted.