SALT LAKE CITY — A flood briefing issued by the National Weather Service in Salt Lake City on Thursday has identified three areas across the state at highest risk for flooding, depending how April weather behaves.
Those areas include the Logan and the Blacksmith Fork rivers up north and the Weber River at Oakley and at Chalk Creek near Coalville. Also at risk are Emigration and City creeks because of mountain snowpack that is 187 percent of normal.
In the briefing by Brian McInerney, the service's hydrologist, the agency stressed flooding with such significant snowpack hinges on what type of April weather pattern emerges in the weeks to come.
That behavior — whether mild and dry or wet and cold — will shape how the snowpack comes off the mountains in either an "orderly fashion or all at once."
McInerney said the highest flood risk is at those northern rivers in Cache County, where the threat of property damage is "quite high. Mild temperatures with below average rainfall will help."
In 2006, a water year in which snowpack was also substantially high, summer homes in Logan Canyon were damaged. Oakley had flooding problems last year, even with a feeble snowpack, because of above-normal temperatures on one day in June that caused a rapid snowmelt.
City and Emigration creeks are a concern because even though they are small creeks, any flooding has the potential to damage multiple structures and streets.
McInerney said because City Creek flows underground at one point beneath North Temple, a flood event could pop off manhole covers.
The flood briefing is one of six such informational alerts that will be distributed by the Salt Lake office of the National Weather Service, which has also created its own Facebook page to help spread information. Users who want to hear the briefings can "like" the National Weather Service Salt Lake City and have access to charts and other information related to inclement weather events.
As a result of the potential for flooding, Salt Lake City is also advising residents on what steps it is taking to minimize property damage. It warns to keep small children and pets away from the streams because of high flow rates.
The city is monitoring flow rates in and out of reservoirs and is clearing and maintaining stream channels. It is also stockpiling sandbags.
For flooding emergencies in Salt Lake City, residents should contact the department of public utilities' 24-hour dispatch at 801-483-6700 opt #1.
Real-time stream flows are available at www.pweng.slco.org/flood/streamflow/index.cfm.