The road begins at Mlolongo, connects JKIA to the CBD, and ends in Westlands.
On completion, it will be the third highest bridge in Africa.
The project has been delayed by land compensation disputes.
The project has a contract sum of $163m (Sh18.7 billion).
The project is co-funded by the Japan Int. Cooperation Agency.
The project is on schedule for final completion this year.
The 457-metre bridge replaced a causeway built by colonialists in 1929.
The plant has been connected to the national grid.
The project is being undertaken by BOMI E&C Consortium.
The 70km road will be upgraded to bitumen standards.