
The 20.9 km Port–Maduravoyal Expressway is being built as a double-decker corridor, passing through key city areas and running largely above the Cooum River.

The first 5.7 km stretch from Vanagaram to Koyambedu will remain single-deck, as older pillars built in 2008 are being reused with existing foundations.

The old pillars are being strengthened with fresh concrete to support an 8-metre-high flyover, which later expands into a double-decker corridor inside the city.

After entering the Cooum River at Padi Kuppam, the flyover expands into a second corridor at 16 metres height near VR Mall after crossing 100-Feet Road.

Beyond the Maduravoyal clover-grade separator, new pillars have been constructed at 8 metres height, while retrofitting work continues on older pillars along the route.

About 25 double-decker pillars have been placed across the Cooum River in areas like Egmore and Chetpet, where construction is faster due to minimal disturbance.

The lower corridor will serve city commuters with exit ramps at key locations, while the upper corridor will provide uninterrupted connectivity directly to Chennai Port.

Both corridors will be toll-charged despite running within city limits, following a model similar to other elevated urban expressways in major Indian cities.

NHAI is casting around 2,000 segments at a 60-acre yard, with several segments already installed, especially near Shanthi Colony and Koyambedu areas.

Barricades on Poonamallee High Road have reduced carriageway space for nearly two years, causing traffic issues, especially at night, with limited alternative routes provided.