At a press conference, he showed a copy of a police complaint filed by a PWD engineer, alleging that he was threatened after he thwarted the attempt by the workers of a company to damage a drain at Nangloi in 2016.
The company in question was owned by Mr Kejriwal's relatives -- Surender Bansal and his son Vinay Kumar.
"Kejriwal shielded his relatives' company which damaged drains and roads in order to obtain repair orders. In many cases, no repair work was carried out, but payments were still made on forged work completion certificates.
"Kejriwal's role in this scam should immediately be probed by the CBI or the Anti-Corruption Branch (ACB)," said Mr Tiwari.
Earlier this week, the ACB lodged three FIRs, including one against a company of Mr Bansal, regarding a "scam" in the PWD.
The FIRs were lodged on the basis of a complaint from Rahul Sharma, the founder of an NGO, the Roads Anti-Corruption Organisation (RACO).