Wednesday, May 11, 2011

Monitoring Spring Runoff

The Tooele County Commission is vigilantly monitoring the potential for spring flooding this year. Commissioner Bruce Clegg and County Engineer Vern Loveless make regular patrols of specific areas of concern. However, while electronic news media are painting a gloomy picture on the Salt Lake City side of the Oquirrh Mountains, Clegg and Loveless agree that the situation in Tooele County is manageable.

Long-time residents of Tooele County will remember the flooding of 1983. City streets were turned into roaring rivers. Roads and yards were washed out. Homes were flooded. People all around the Tooele Valley were recruited to fill sand bags. I remember getting out of church early on a Sunday afternoon in Erda to go fill sand bags in Tooele.

The good news is it’s unlikely that we’ll see a repeat of that disaster. Utah Snotel measurements indicate that the Oquirrh Mountains are at 145% of normal for water equivalent, the amount of water contained in the snow. That’s only about half of the water content we saw during the winter of 1982-1983. The only factor of real concern now is how fast the temperatures will increase and bring down the water that is up in the mountains.

More recently, people will remember the flash flood of Memorial Day 2005. However, that was caused by a three hour continuous downpour, not spring runoff. Loveless points out that that’s a significant difference. “This is a snow melt event, not a cloudburst. We can see flood conditions arise over days, not minutes,” he said. Commissioner Clegg added, “With this type of event we’ll have enough warning to take proactive measures if the water exceeds flood controls.”

The other good news is that in the years after the floods of 1983, FEMA paid to install several new flood control measures in Tooele County. Those flood control measures include construction of a ditch and dike designed to divert water coming out of South Willow and North Willow Canyons away from residences and towards Tooele Army Depot and an aquifer recharge zone (absorption area) just south of SR-112; installation of larger culverts under SR-36 north of the viaduct and near 700 South; installation of larger drainage pipes on the south side of Tooele; and excavation of deeper flood control channels along the border between Tooele City and Erda.

In spite of the positive outlook, city and county engineers, public works and roads employees, irrigation company managers, and emergency management are working hard to mitigate any potential flood waters. Recent mitigation efforts include inspecting and maintaining the flood control measures installed with FEMA funding, cleaning drainage ditches and flood control channels, and filling sand bags.

There are several areas that officials are focusing on right now. They are Settlement Canyon, Middle Canyon, the South Willow Canyon and North Willow Canyon drainage, Ophir Canyon, Hickman Canyon, and the Vernon drainage. So far none of those areas are showing any signs of flooding.

Commissioner Clegg is working closely with Tooele County Emergency Management (TCEM) and with other officials to coordinate snow melt information weekly. TCEM creates a SitRep or Situation Report, containing details of the current situation and mitigation efforts. That SitRep is distributed to, and reviewed by, all local governments. TCEM has also supplied more sand bags to local municipalities, and is documenting efforts in case an emergency is declared and reimbursement is available.

You may be wondering what you can do to help. As for any natural hazard potential, have a family disaster plan and disaster supplies kits; maintain situational awareness, meaning be aware of what’s going on around you; consider purchasing flood insurance; report areas of concern to your local government officials; and monitor warning systems if an emergency does occur. People are also encouraged to organize cleanup efforts to remove trash, weeds, and other debris from gutters, storm drains, and drainage ditches that may exist around your home or in your neighborhood.

Emergency Preparedness information is available in many forms at the TCEM Building at 15 East 100 South in Tooele. You can consult your 2011 Tooele County Emergency Preparedness Calendar. Information is also available electronically at www.tcem.org, or by following TCEM on www.Twitter.com, @TCEM; and on Facebook: www.facebook.com/tcem.org. Feel free to call (435) 833-8100 with emergency preparedness questions.