The Cowichan Region was impacted by a series of atmospheric rivers. Environment and Climate Change Canada reported that between 11:00 a.m. on November 13 and 11:00 a.m. on November 15 a total of 68.2 mm of rain fell, which far eclipsed the old rainfall record of 54.3 mm set in 1913. The result of this unprecedented rainfall was significant flooding across the Cowichan region. Several Evacuation Orders were subsequently issued and the Regional Emergency Operations Centre was activated. Infrastructure damage included roadways, diking and other protective works across the region. Some land slippage also occurred in region.

A 20 hectare wildfire on the Eastern side of Mount Hayes was responded to the evening of August 19, 2021. It quickly grew to 70 hectares overnight, nearing critical infrastructure of a repeater tower site and the Fortis BC liquid LNG storage facility. A total of 56 firefighters, 12 pieces of heavy equipment and 5 helicopters supported the firefighting efforts over the following 5 days. Several evacuation orders and alerts were issued to the surrounding residents.

Due to the extreme heat wave anticipated in the Cowichan Valley, cooling centres were opened at several locations:

• Kerry Park Recreation Centre, 1035 Shawnigan-Mill Bay Road, Mill Bay – Thursday July 29 – Saturday July 31 from 12 pm to 8 pm.
• Cowichan Community Centre, 2687 James Street, Duncan – Thursday July 29 – Saturday July 31 from 12 pm to 8 pm.
• Lake Cowichan Centennial Hall, 309 South Shore Road, Lake Cowichan – Thursday July 29 – Saturday July 31 from 12 pm to 8 pm.
• Frank Jameson Community Centre, 810 – 6th Avenue, Ladysmith – Thursday July 29 – Saturday July 31 from 12 pm to 8 pm.
• Siem Lelum Gymnasium, 5574 River Road, Duncan – Thursday July 29 – Saturday July 31 from 12 pm to 8 pm.
• Crofton Community Centre, 8104 Musgrave Street, Crofton – Saturday, July 31st from 12 pm to 8 pm.
• Chemainus Seniors Centre, 9824 Willow Street, Chemainus – Saturday, July 31st from 12 pm to 8 pm.

An atmospheric river brought heavy rains with a station at Effingham Inlet, off the west coast, recording nearly 300mm of rain in one day. Both Cowichan River and Chemainus River were above a 5-year flow and continued to rise. Around 10 p.m. on January 31, flooding in areas of Crofton resulted in the evacuation of about 23 people. A BC Transit bus was used to bring 18 residents to the Duncan area to stay with friends and family, and the rest were accommodated in Crofton. Evacuations continued into the early morning and at 3 a.m. the Cowichan Community Centre opened as a group lodging and reception centre for about 28 evacuated residents from North Cowichan and the Halalt First Nation.