Flood watches have been issued for several major waterways after torrential downpours hit parts of southern and central British Columbia.

The River Forecast Centre says rivers throughout the Columbia and East Kootenay regions, including tributaries around Golden, Revelstoke and the Columbia Valley, are rising.

The centre says rivers and streams are expected to approach or exceed flood levels today, while the Shuswap and South Thompson rivers are also high enough to burst their banks.

Further north, flood watches have been issued for the Skeena River and its tributaries, including the Bulkley River in northwestern B.C., and for waterways throughout the South Peace region, which encompasses Tumbler Ridge, Chetwynd, and Mackenzie.

Environment Canada says 30 millimetres of rain was expected in the southern and central Interior on Friday and it issued rainfall warnings for a large section of northern B.C.

A news release from the forecaster said drenching rain had been falling in the Skeena and south Peace regions since Thursday.

"Rainfall totals observed so far have been in the 15 to 50 millimetre range through the Skeena, Bulkley and northwest B.C., and 15 to 60 millimetres through the Peace, Williston, and Mackenzie region," the release said.

The downpour is being blamed for a washout that closed Highway 1 about 25 kilometres west of Revelstoke. The closure is expected to be in place until at least Sunday, which will add hours to road trips for travellers.

Environment Canada says rainfall warnings have been issued for much of north-central and northeastern B.C., with up to 25 millimetres forecast for some areas Friday, in addition to the 15 to 25 millimetres that fell Thursday.