The NHAI attributed the decision to the existing alternative national highway between the two capitals and traffic volume.

The existing 326 km Chennai-Bengaluru bypass road sees more than 75,000 vehicles per day, and cannot hold additional traffic. Thus, the eight-lane expressway was proposed to meet the rising industrial demand on the stretch and provide faster connectivity for end-to-end travellers.

The proposed 262 km expressway is expected to reduce the travel distance by 50 km. It will begin at Hoskote in Karnataka and end at Sriperumbudur in Tamil Nadu, passing through V Kota and Palamaner in Andhra Pradesh, and Arakkonam and Gudiyattam in Tamil Nadu.

Consultants appointed by NHAI and a few other agencies conducted multiple feasibility reports of the project before the Centre approved it.

Land required for the project was estimated for an eight-lane expressway. For 72 km of the expressway in Karnataka, 817.60 hectares are required, while 918.52 hectares are needed in Andhra Pradesh for 85 km, and 833.91 hectares in Tamil Nadu for 106 km.

Reduction in the road's width was decided considering the traffic and other routes between Chennai and Bengaluru.

An official document of NHAI said that it was proposed to build the four-lane expressway in such a way that it could be expandable to eight-lane.

The NHAI said the expressway would have a depressed median that enables future widening of the road from the inside. Provisions are being made in a manner that the roads can be widened in the future without any additional land acquisition.