Fruitgrowers Rd near Clyde remains closed as a slip on the hillside threatens to dump more sizeable rocks and gravel on the road.
The road, past the Clyde dam, on the opposite side of the Clutha River to State Highway 8, was closed on Sunday after a rockfall near the dam.
Central Otago District Council roading manager Julie Muir said the slip was being monitored by geotechnical engineers for movement higher up the face after yesterday's heavy rain.
There were no recorded earthquakes in the area which might have triggered the slip, so it appeared to be an unstable mass, which was relatively shallow, she said.
''I think the central mass will slip and block the road and it's not safe to get in there just yet, so we'll keep the road closed as a precaution. Some of the rocks which have already fallen and some of the ones poised to fall are quite sizeable rocks.
''We'll give it a couple of days to see if it comes down before having any discussion about what we can do [to hasten the process].''
Ms Muir said power lines at the base of the slip were moved by Delta staff on Sunday.
Fruitgrowers Rd leads in to the Dunstan Arm Rowing Club headquarters, Weatherall Creek and Burton Creek.
An access road across the dam is open as a temporary measure. Contact Energy hydro generation manager Graham Quinn said there had been other, smaller rockfalls on that road in the past 18 months.
Although Contact's offices were nearby, he had no concerns about the slip: ''It would have to travel quite a way, over the road, over a flat, benched area and even if it did that, the diversion sluice is also in the way.''
The Milford Rd was closed last night from the Hollyford turn-off because of heavy rain.
It will be reassessed at 8am today.
Transport Agency senior network manager Peter Robinson said snow was also forecast, with 5-10cm predicted to 400m and 10-15cm above 800m last night.
Homer Tunnel is about 900m above sea level.
