The new bridge, scheduled to open late next year, will replace the single-lane structure (foreground) that has formed a critical link for more than 137 years on the main highway between Dunedin and Central Otago.
The bridge piles are being drilled 14m into solid rock in the riverbed.
Once completed, State Highway 8 will cross the Clutha River over a two-lane, 195m steel girder bridge supported by four piers within the riverbed.
Waka Kotahi NZ Transport Agency said the existing bridge was well past its economic life and was now challenged by larger traffic volumes, including bigger and heavier trucks.
When the replacement opens, the existing single-lane bridge will remain as a link to the popular nearby Clutha Gold Cycle Trail.