River Forecast Centre Warns of Flood

By 250 News

    The good news is, the  Ministry of the Envrionment says the  winter snow accumulation season is pretty much over.

The bad news is the River Forecast Centre is  forecasting well above normal spring  runoff  in most river basins, and possibly  higher  risks of  flooding in  areas  like Prince George and the Central Interior where there has been increased logging activity  in the wake of the Mountain Pine Beetle. 

The report says  that as of April 1st, very substantial snowpacks have accumulated over large portions of the province. 
The flood risk has increased over the past month, as a result of the well above normal snow accumulation throughout most of B.C. during March.  There were some exceptions,  like the Okanagan, Kettle, Similkameen and the Kootenays.
The risk of flooding on smaller streams and rivers in the river basins noted below is high.   Whether or not significant flooding occurs on major river systems will depend primarily on the weather during snowmelt in May and June, and when and how rapidly snowmelt occurs.

Areas under flood risk include much of the B.C. Interior, including the following rivers and their tributaries:

• The Fraser River and its tributaries (from its headwater areas above Prince George through to the Lower Mainland)
• Nechako River
• Bulkley River
• Nass River
• Skeena River
• Peace River (tributaries and inflows to Williston Reservoir, but not the Peace River below Williston Reservoir)
• North and South Thompson rivers.

Work has already begun in Houston to upgrade a dike along the Bulkley River.  That is a $29 thousand dollar project being funded under the Provincial government’s urgent flood mitigation works program.,

Here are the detials of the latest snow pillow report, with all measurements reflecting data collected April 1st.

Upper Fraser:  Has one of the largest snowpacks recorded in more than 50 years.  The April 1st snow water index  was 139% of normal, thats up from 132% on March 1st.  Low elevation snow is well developed,  and is 130% of normal  while mid and high elevation snow is 120 - 160% of normal.  Areas with the highest meassurements are :  Bird Creek 188% of normal  Burns Lake 197% and McBride - Upper  at 150%

The Nechako:  The Nechako snow water index is 159% of normal. This is a new record for the basin, and is a significant increase from 148% at March 1st. The Mount Pondosy , Mount Wells  and Tahtsa Lake snow pillows range between 143% and 185% of normal. The Skins Lake snow course is 166%. The Tahtsa Lake snow course is 153%, a record high value for April 1st based on 55 years of measurement. Low elevation snow is well developed throughout the Nechako, and is near 150% of normal. The record snowpacks in the Nechako produce a high likelihood of flooding. There is potential for flooding to be exacerbated by the extensive Mountain Pine Beetle infestation throughout the Nechako basin.

The Middle Fraser has an April 1st snow water index of 130% of normal, an increase from 124% at March 1st. Most snow courses, from low elevation to high elevation, are in the 115-150% range. Notable measurements are: Puntzi Mountain 194%; Bridge Glacier  - 152%; Mission Ridge - 153%; and Bralorne - 139%.

The Lower Fraser has a snow water index of 124% of normal, a decrease from 130% at March 1st. The Lower Fraser received well above normal precipitation during March (235% of normal at Abbotsford), but mostly as rain. The rain, combined with above normal temperatures, produced substantial melt of low elevation snow. Notable measurements are: Tenquille Lake  170%; Stave Lake 117%; Dickson Lake 138%; and Chilliwack River  140%.

The Thompson River basin  has above normal snow water conditions.The North Thompson is 116% of normal, and the South Thompson snow water index is 109% of normal. Both are near their March 1st levels. Some locations, particularly in northern portions of both the North and South Thompson, received significant new snow accumulations during March.

The Skeena/Nass basins (including the Bulkley River) have a record high snowpack for April 1st. Their overall snow water index is 151% of normal for April 1st, increased from 144% at March 1st. Many snow courses in the Skeena and Nass have established new record highs for April 1st, including: Ningunsaw Pass  153%; Lu Lake 158%; Kidprice Lake  174%; and others.

The Terrace A snow course is an astounding 347% of normal (with 27 years of record).

Other north coastal locations are currently at a record high snow accumulation for April 1st, surpassing 1999 records Burnt Bridge Creek is 203% of normal and Tahtsa Lake ( is 153%.

The Stikine/Taku basins have an average index of about 137% of normal, increased from March 1st.

The province’s  River Forecast Centre website  has more detailed information: http://www.env.gov.bc.ca/rfc/.

Email | Print | Facebook | Twitter | Digg | Del.icio.us