Serious crack in Columbia dam affects hydroelectric system

EPHRATA, Wash. (AP) — A crack in a spillway pier at the Wanapum Dam on the Columbia River is a serious situation, but not a threat of downstream flooding even in a worst-case scenario, a spokesman for the Grant County Public Utility District said.

The 2-inch-wide underwater crack extends horizontally across the upstream side of the 65-foot wide pier called a monolith. It’s one of 12 monoliths on the spillway.

“Say this section were to fail completely,” spokesman Tom Stredwick said Monday. “The remainder of the spillway would remain intact and with the current amount of water in the river, the water through that section of the dam would still be normal for this time of year.”

The problems may arise in managing the river flow and power production from the network of Columbia River dams.

“We’re in a coordinated river system,” he said.

The utility is working with the Federal Energy Regulatory Commission and the Bonneville Power Administration to determine the long-term impacts, Stredwick said.

The first step is to assess the damage and determine what it will take to repair the Wanapum crack.

The reservoir behind the dam is being lowered 20 feet. That should be completed late Monday or early Tuesday, relieving pressure and helping with the inspection, Stredwick said.

Pressure caused a slight bowing in the dam that was first detected Feb. 24 by a staff member who noticed a curb on the road on top of the spillway was out of alignment. Engineers sent down divers who discovered the crack Thursday, 75-feet below the waterline. The crack extends all 65 feet across the monolith, which is 126 feet tall and 92 feet thick. Stredwick doesn’t think the crack extend all the way through the pier.

Continuous surveying shows no additional bowing in that section of the dam, he said.

The 51-year-old dam is a mile long, spanning the Columbia about 5 miles downstream of where I-90 crosses the Columbia River at Vantage in central Washington. Its reservoir extends about 40 miles upriver to the Rock Island Dam, near Wenatchee, Wash. The next dam about 20 miles downriver is the Priest Rapids dam, near the Hanford nuclear reservation.

The Wanapum and Priest Rapids dams are both owned by the Grant County PUD and operated under federal licenses.

The Wanapum Dam can generate 1,092 megawatts, enough to supply 900,000 homes. The utility has 46,000 residential, business and farm customers. It sells surplus electricity through the grid.

Wanapum Dam continues to generate electricity and should continue to do so, but a crack of that magnitude is definitely unusual.

“This is a serious situation for us,” Stredwick said.

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Parkdale third graders sing "12 Disaster Days of Christmas"

Welcome to your sing-able Christmas gift list. What follows is an emergency rendition of “12 Days of Christmas” – for outfitting your home or car in case of snow storm, earthquake, flood or other emergency. Read it as a simple list, or sing it to the tune of “12 Days” – you know, as in “ … and a partridge in a pear tree…” Not to make light of it, but the song is a familiar framework for a set of gift ideas that you could consider gathering together, even if the recipient already owns items such as a bunch of coats, tire chains and flashlights. Stores throughout the Gorge are stocked up on all these items. Buying all 12 days might be prohibitive, but here are three ideas for checking any of the dozen off your list (notations follow, 1-12.) The gift items needed to stay warm, dry and safe are also coded to suggest items in your abode (A) in your car (C) or both (B). 12 Gallons of Water (A) 11 Family meals (B) 10 Cans of propane (A) 9 Hygiene bags (B) 8 Packs of batteries (A) 7 Spare coats (B) 6 Bright red flares (C) 5 Cozy blankets (B) 4 Tire chains (C) 3 Flashlights (B) 2 cell phone chargers (B) 1 And a crush-proof first aid kit (B) Price ranges? Here’s a few quotes for days Three, Two, Four and Nine: n A family gift of flashlights (three will run $15-30, Hood River Supply, Tum-A-Lum) n Cell phone chargers (two will run $30-60) n Tire chains (basic set, $30, Les Schwab, returnable if unused for the winter) n Family meals ($100 or so should cover the basics for three or four reasonably well-fed days) n The home kit should be kept in a handy place near an exit, and remember that water needs to be replenished every few months. If you have a solid first aid kit already, switch out the gift idea with “and-a-sto-o-u-t- tub-for it-all …” Otherwise, it’s a case of assembling your home or car kits and making sure all members of the family know what the resources are and how to use them (ie flares and propane). Emergency situations are at worst life-threatening, at best deeply uncomfortable if you and your family are left without power for an extended period, or traveling and find yourself in a situation where you need to wait out a storm, lengthy traffic delay, or other crisis. Notes on the 12 gift ideas: 12 – Gallons of water: that’s one per person in a four-member family to last for three days, the recommended minimum to be prepared for utility outages. 11 – Easy-open packaged goods, energy bars, dried food and nuts are good things to include for nutrition. Think of what your family of four needs for three days to stay fortified and hydrated (see number 12). Can-opener also recommended 10 – If you have a propane camping stove, keep extra fuel handy. 9 – Hygiene bags: put packaged moistened towelettes, toilet paper, and plastic ties in large garbage bags (for personal sanitation) Resource list courtesy of Hood River County Emergency Management, Barbara Ayers, manager/ 541-386-1213. The county also reminds residents to Get a Kit, Make A Plan to connect your family if separated, and Stay Informed. See www.co.hood-river.or.us to opt-in for citizen alerts. Enlarge



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