The project was funded by $1 million from the State Government and the City of Swan and has taken 14 months to complete.
Drivers now have an easier commute from Ellenbrook to Midland along West Swan Road.
City of Swan CEO Mike Foley said the final asphalt wearing course was laid last Wednesday and Thursday nights .
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READ NOW‘Minor works, such as road markings and landscaping, will take place later and should have minimal impact on road users,’ he said.
Readers turned to The Advocate’s Facebook page to express their delight at the much-anticipated roundabout.
Andy Thompson said: ‘Much better with the roundabout in place. Now drivers turning right on to West Swan Road from Gnangara have a fighting chance.’
Swan Valley Regional Network co-ordinator Sue Hurt said residents would welcome the Henley Brook roundabout.
She said although the Benara-West Swan Road roundabout worked well, the Gnangara Road roundabout still needed a little more work to address peak hour issues.
‘There is still a bottle neck because people in peak hour turning right on to West Swan Road do not give way to the right. That has to be fixed but overall it’s a big improvement.’
The State Government has committed $14 million to complete a dual carriageway on Gnangara Road from Alexander Drive to West Swan Road and $8 million next year to install traffic signals at the nearby Lord Street and the Reid Highway intersection. When completed, the projects should result in a better traffic flow through the Swan Valley.