The roofs of a number of homes and businesses collapsed under the weight of the ash and residents feared for their sheep and cows.
Soldiers have been deployed to help with the clean-up.
The authorities have warned of the possibility of further eruptions.
They also said that should it rain, the ash could mix with debris to create dangerous mudflows.
The Calbuco volcano in southern Chile erupted twice last week, forcing the evacuation of more than 6,000 people.
Chilean authorities said on Saturday that the volcano had spewed out an estimated 210 million cubic metres (7,420 million cubic feet) of ash.
Local resident Victor Hugo Toledo said the area looked like a “grey desert”.
“Wherever you look all you see is grey dust; there is an average of 50cm (20in) of it over the towns and on all the roofs,” he told the Associated Press news agency.
The authorities allowed some of the residents evacuated from the town of Ensenada to return briefly in order to try to save some of their belongings.
Rony Alvarado found that the roof of his restaurant had collapsed under the weight of the ash.
“Eleven years of work [gone] in one day, one second,” he said.
On Saturday, the Chilean government announced it would provide aid to cover huge financial losses incurred by local farmers and to help evacuate thousands of farm animals.
The second eruption on Thursday created a cloud of ash that rose 20km (12 miles) into the air.
Calbuco is one of around 90 active volcanoes in Chile.
The country has been hit by a series of natural disasters in recent months including flooding in the usually arid north and wildfires in its southern forests.