A Coombs there is a nature reserve "Molonglo River Reserve" straddling the Molonglo River.
There are 2 bridges over the river, but the path leading to one has been damaged by floodwater (but the bridge is OK). The bridges take you to the reserve on the other side, with good tracks all around. It is the smaller one that is problematical if you have mobility issues. It's probably a 10-minute walk from the road to the main bridge.
Here there is easy access to the river and a good opportunity for pictures of the river, riverbanks, rapids, and the bridges themselves.
So far I've only explored the area adjoining the bridges, even though the reserve extends a lot further.
There isn't any off-street parking near the 2 bridges, so you'll have to park in one of the nearby streets. You can often find parking on Harold White Ave where it enters the suburbs.
There's also no direct path to the bridges from the road, so you have to find one of the entrances to either side and follow a trail down to the river. It's not far.
The walkway to this bridge has been partially washed away.