Chennai Bypass

The Chennai Bypass is a full-access controlled expressway that interconnects four radial Indian National Highways around Chennai, India covering a distance of from Perungalathur (near Tambaram) on NH45 to puzhal on NH 5 via Maduravoyal at a cost of 4.05 billion. Constructed as part of the National Highway Development Project to decongest the city of transiting vehicles, the expressway interconnects NH45, NH4, NH205 and NH5. This expressway now forms a part of the circular transportation corridor.
Phases.
Phase I.
The first phase is six-lane fully access controlled carriageway from Perungalathur on the Grand Southern Trunk Road (NH 45) to Maduravoyal which lies on the Chennai–Bangalore NH-4. A 3-tier trumpet interchange has also been constructed at the starting point at Irumbuliyur. It was inaugurated in April 2008. The Road runs through Thiruneermalai, Pammal, Anakaputhur, Tharapakkam, Kovur, Porur, Vanagaram to reach Maduravoyal.
Phase II.
The second phase include extending the bypass by from Maduravoyal to Puzhal on the Chennai–Kolkata NH5 and four-laning it. It also includes two interchanges. A clover-leaf grade separator at Maduravoyal Junction and a trumpet interchange at puzhal where the bypass phase II ends.
Elevated Road.
A elevated six-lane corridor forms the part of the Phase II being executed currently. This elevated road cuts through the Industrial Estate in Ambattur. This corridor ends with a Road over bridge (RoB) crossing the Chennai–Jolarpet railway line. The elevated corridor was completed in June 2009 at a cost of 1000 million.