The approval of stage 2A to the lake was real evidence of the tram growing into a city-wide network, rather than a single route oddity that never reached the majority of the community.

But of course the lake and the bridge spanning it remain the biggest and most complex obstacles to the tram reaching its next major destination of Woden and the future destinations beyond.

While much work still needs to be done to clear those complexities and see the link to Woden become a reality, this week's approval does raise questions about another recently announced decision along that proposed route.

On the face of it, former ACT opposition leader turned federal Senator Zed Seselja's announcement in January of a $137 million upgrade for the Commonwealth Avenue bridge is wonderful news for the territory.

In his announcement of the federally-funded bridge upgrade, Senator Seselja talked of jobs, investment and "infrastructure projects such as these that make a real difference for the day-to-day lives of Canberrans and of course, for local jobs and the economy at this vital time".

And as expected, ACT Chief Minister Andrew Barr, responded in kind, saying the upgrade "will ensure that the bridge will continue to operate as a critical piece of our city's transport infrastructure for decades to come".

Structural work has been planned on the ageing concrete bridge, sitting in a "designated area" as defined under the National Capital Plan, for some time.

The business case for the upgrade says it "fails to meet minimum safety requirements in areas such as the safety barriers, the traffic lane widths, the shared pedestrian and cycle path widths, and the accessibility of existing approaches".

The bridge is effectively already operating at its maximum theoretical capacity of approximately 4000 cars per hour on each span, and traffic demand is forecast to grow by more than 25 per cent by 2036.

So the bridge work was needed sometime, well, soon-ish.

But it is puzzling that such a major refurbishment of the bridge would go ahead without real consideration of light rail and its needs.

Underscoring any practical considerations is the enmity and broad philosophical divide between right-wing Senator Seslja and the left-leaning Barr-Greens ACT coalition government.

Back in 2015, Senator Seselja labelled the ACT's light rail project a "dud".

More recently he pushed for a parliamentary committee enquiry into the extension, claiming the ACT government "didn't get the process right the first time around".

Behind the scenes, the public servants are far more phlegmatic.

Infrastructure Australia identified the light rail extension in its business case and a joint steering committee is being formed to at least ensure the hardhats working on the two projects are talking to each other.

At a local level, technical studies are under way to inform future design and engineering plans for a light rail bridge over Lake Burley Griffin.

The rail extension is planned to link the city to Woden, a planned new CIT, and an expanded Canberra Hospital.

As it forms a key visual element in the broad sweep of one of Canberra's - and Walter Burley Griffin's - most treasured vistas, the Commonwealth Avenue bridge aesthetic now, and into the future, is of vital importance.

The realisation of the stage 2B Woden light rail link will be a significant challenge from an engineering, heritage and budgetary perspective.

To give southsiders the long awaited link that was promised ahead of the election, politics needs to be put aside to ensure we achieve the best possible outcome.