Rainfall warnings are in effect for Metro Vancouver, the Sunshine Coast and most of Vancouver Island with up to 100 mm of rain, while the central and eastern Fraser Valley and Howe Sound could get up to 150 mm of rain.
The continued deluge has prompted the BC River Forecast Centre to issue a flood watch for the Coquihalla River.
A flood watch is also in place for the the Fraser Valley and surrounding tributaries, Fraser Canyon tributaries, including those around Hope, the Chilliwack River and the Englishman River near Parksville.
High streamflow advisories are also in effect for Metro Vancouver and the North Shore Mountains, the Sea-to-Sky, Howe Sound, the Sunshine Coast and most of most of Vancouver Island.
The centre said rivers have risen rapidly from rainfall, since Saturday, and has warned people to keep clear of waterways and potentially unstable riverbanks.
An evacuation order has been issued for 34 properties near the Tulameen River in Tulameen.
Low lying properties in Princeton parts of Merritt are also under an evacuation alert.
A reported mudslide on Lougheed Highway near Agassiz has prompted a search and rescue effort to be launched.
The District of Kent has declared a State of Emergency, evacuating some properties along Rockwell Drive after a landslide.
The Fraser Valley Regional District has also declared a State of Emergency.
In Abbotsford, more than 50 homes have been affected by mudslides.
The city has set up an Evacuation Centre at the Abbotsford Recreational Centre at 2499 MacMillian road.
An evacuation alert issued for parts of Abbotsford late Sunday evening including Sumas Prairie, Clayburn Village, Eagle Mountain and the Dawson Road area.
Conditions also forced the closure of numerous roads within the city.
In Maple Ridge, mudslides and flooding have caused the closure of two intersections.
96 Avenue and Spilsbury Road, as well as 224 Street and 132 Avenue, will be shut down until further notice.
Separate mud and rockslides forced the closures of Highway 1, Highway 6 and the Coquihalla Highway near Hope.
The centre lane of the Lions Gate Bridge in Vancouver was also closed briefly closed due to flooding in Stanley Park.
The alerts come in the second day of precipitation from an atmospheric river that made landfall in B.C. on Saturday, and melting snow added to already swollen waterways.
Environment Canada warned of possible washouts, flash floods, localized flooding and water pooling on roads.
People travelling on the Coquihalla Highway were also warned of messy conditions on Sunday, as Environment Canada forecast a hazardous mix of rain and snow.
The national weather agency forecast between 60 and 90 mm of rain, with possible wet snow Sunday afternoon and evening, near the Coquihalla Summit, and a shift from heavy rain to snow on Monday afternoon.
In southeastern British Columbia, Environment Canada issued a winter storm warning for the Trans Canada Highway from Eagle Pass to Rogers Pass.
That route could also get a nasty mixture of weather, with 20 to 30 cm of snowfall Sunday, shifting to heavy rain.
Drivers in all areas are reminded to use their lights and slow down.