The proposal, presented to full council as "extraordinary or urgent business", will see a revised timetable for those routes, with buses running about every 20 minutes from 6.30am to 6.10pm or 6.30pm.
Chief executive Graeme Martin said the proposal worked with the ORC and Dunedin City Council joint working party objectives for public transport.
While declining to give full costings of the proposal in public, for commercial reasons, he said the cost would not affect rates.
"It's a very positive proposal."
It had been deemed urgent as the council was about to print new timetables, including new fare information, he said.
Joint working party co-chairman Cr Michael Deaker said it was the kind of development both councils had been anticipating.
"It will make it easy to use and more regular. It is a very pleasing development."
Under the present timetable, Opoho services finish at the Exchange, rather than continuing through to Shiel Hill.
Similarly, some services from Shiel Hill finish at Frederick St, rather than continuing through to Opoho.
Under the revised timetable, all weekday services except four would be through-routed in both directions.
It provided for 24 services through-routed from Opoho to Shiel Hill instead of 14, and 24 from Shiel Hill through to Opoho, instead of 12.
Timetable gaps would also be filled with 18 extra services.
The new timetable will begin on July 28.
