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.
Beijing wants Kenya to extend the SGR from Naivasha to Uganda.
The new oil terminal will handle bigger volumes of fuel products.
Plans are underway to roll out the projects by end of year.
The 59-metre-high dam occupies a 600-acre site.
Project seeks to ease shortage of houses for military officers.
Beijing has cut financing for Belt and Road Initiative projects.