Divers have discovered an underwater crack in one of the concrete piers, shown, below the fourth spillway gate at Wanapum Dam. The crack was discovered after dam engineers Tuesday noticed some mild irregularities in the concrete of the dam's deck. The Grant County PUD has lowered the reservoir behind the dam by six feet to relive pressure. The dam is still generating electricity as usual while the investigation continues. The dam is on the Columbia River near the community of Beverly, 62 miles south of Wenatchee. Photo provided Grant County PUD
After rising water levels threatened to spill over a massive dam in California, nearly 200,000 people were evacuated from towns that might be at risk below it.
The drama is a reminder that nature doesn’t always tolerate human arrangements for its confinement.
There are nearly 1,200 dams (more than half of them privately owned) in Washington state storing at least 3.2 million gallons of water each, according to a 2016 inventory, and the state has seen its fair share of problems at some of those dams.
Here are a few notable dam incidents in Washington state:
Dec. 23, 1918 — About 2 a.m., the town of Edgewick, near modern-day North Bend, was wiped out after floodwaters seeped through glacial debris near the Cedar River dam.
No one died, but at least 12 families lost their homes and all of their belongings, The Seattle Times reported.
A watchman at a nearby mill saw the creek rise and warned the town before floodwaters traveled down the hillside. A mother and child were plucked from rushing waters in a heroic rescue, the Times reported.
Feb. 26, 1932 — Edgewick saw more tragedy just 14 years later. About 25 people had resettled in the area by the time warm and wet weather sent floodwaters raging through the area again, according to HistoryLink. The Milwaukee Railroad had constructed a berm and culvert while working on a bridge in the area. After it became clogged, water burst through with no warning.
Seven people died and two were injured after they were trapped in their homes. Some victims were never found; others were crushed to death, HistoryLink reports.
April 19, 1938 — At least 25 homes and businesses were swept into the Okanogan River when floodwaters broke through a dam on Loop Creek in Malott Valley.
“Residents, with barely a half-hour warning of the breaking dam, fled homes and businesses. The state highway was washed out for a quarter mile. Telephone communication was severed,” the Times reported.
Oct. 5, 1991 — Without warning, reservoirs above a steep hill in Centralia failed and “discharged into a crowded neighborhood,” according to a Department of Ecology report.
Boy Scouts working nearby “were able to scramble out of the way of the flood wave,” according to the Ecology Department. Two homes were knocked off their foundations and others were damaged. No one was killed.
2006-2009 — The Howard Hanson dam was damaged by storms and began to seep. The Army Corps of Engineers began interim repairs in August 2009, to keep areas along the Green River in Kent, Renton, Auburn and Tukwila from flooding.
A year later, the U.S. Senate approved $44 million in emergency funding to permanently fix the dam’s embankment.
April 2010 — A 21 million-gallon manure lagoon at a dairy farm in Snohomish County suffered a “catastrophic” breach, and sent manure into fields, the French Slough and the Snohomish River. No one was killed.
FebRUARY 2014 — Officials found a 65-foot-long crack in the 185-foot-tall Wanapum Dam on the Columbia River. Water levels had to be lowered for more than a year, according to Capital Press. Repairs reportedly cost nearly $70 million.
OctOBER 2015 — Six dam workers were injured after an explosion at the Priest Rapids Dam on the Columbia River.
