Tram services to Glenelg will temporarily close for six months in 2025 to make way for construction on a tram overpass in Adelaide's south.

The South Australian and federal governments will each contribute $100 million towards the Morphett Road overpass at Morphettville.

An estimated 25,000 motorists travel through the area daily with the government saying boom gates are down for up to 16 minutes each hour during peak times.

The government said more than 106 crashes and 40 injuries occurred in the project area between 2019 and 2023.

The works will shut down tram services to Glenelg for six months in the second half of 2025 and will be replaced by busses between Glenelg and South Terrace. 

Transport Minister Tom Koutsantonis said the upgrade would make enough space for cyclists, pedestrians and new housing developments.

He said construction should begin at the same time as other level crossings on Cross Road, Marion Road and Anzac Highway.

"It will mean congestion at Marion Road, it will mean some congestion at Cross Road, it will mean some congestion on South Road and Morphett Road while we're building this, but when it's finished, it will be well worthwhile."

Local MP Jayne Stinson said, once completed, the project would alleviate pressure on roads in surrounding suburbs.

"We have a lot of additional housing being built in this area and that's putting pressure on our roads. This is a solution to that," she said. 

"If we're going to have that increased population in inner areas…then we need to provide the infrastructure for that and this absolutely delivers on that."

City of Holdfast Bay Mayor Amanda Wilson said the infrastructure investment was "a gain" for the local community.

She said she would be working with the department to "coordinate" the upgrade of Jetty Road and the tram construction to lessen the impact on surrounding businesses.

"We'll be hoping to coincide our works down here with upgrading Jetty Road with the downtime for the tram," she said.