Downstream residents dodge bullet after Lake
Delhi dam fails
Gazette
online
Cedar Rapids, Iowa
Posted on Jul 25, 2010 by
Orlan Love.
see updated photos
 |
The Lake Delhi dam failed Saturday as
rising floodwater from the Maquoketa River ate a
30-foot-wide hole in the earthen dam, causing water to
drop 45 feet to the river below and threatening – at
least for a while – a few towns downstream. “I’ve
never seen anything like it,” said DNR Environmental
Specialist Tom McCarthy who was on the scene Saturday. |
| Aerial view
of the Lake Delhi Recreation Association Dam after it
had been compromised. (Mark Benischek) |
Fred DeShaw, 52, of Worthington, said he
was only about 150 feet away when the earth gave way at
the dam in Delaware County. He estimated a swath about
125 feet wide and 30 feet deep opened up before his eyes
as a “roar” of water went through.
See all the photos |
“Anything and everything was going through,” DeShaw said.
As the river began to flow over the top of the dam, the man
who knows the most about the structure discussed its demise
not in terms of if it would be breached, but when.
“This is a warning, not a watch. I don’t like the look of
it,” Dave Fink, dam operations supervisor for the Lake Delhi
Recreation Association, said around 11 a.m. Saturday.
With water coursing across the south approach to the dam
and half the roadway on the north side undermined by moving
water, Fink said, “I think one of the approaches would be the
one to go.”
At 12:49 p.m., when the first large chunk of roadway
disintegrated before the horrified eyes of more than 100
onlookers on both sides of the river, Fink’s formerly
pessimistic assessment suddenly seemed realistic.
With the lake level about 15 feet higher than the openings
in the dam, water roared into the ever-widening breach,
quickly cutting a gorge through which the impounded water
cascaded 40 feet to the river below.
As more of the roadway gave way, utility poles toppled into
the flood, and adrift boats and docks from the lake crashed
into the opening. A liquid propane tank ignited just below the
dam shooting flames high into the sky, adding to the disaster
movie impression.
“I’ve seen fully grown trees washed downstream in less than
a minute,” said McCarthy, the DNR specialist.
Though Fink and public safety officials feared a
catastrophic release of water and pent-up energy, especially
in the immediately downstream towns of Hopkinton and
Monticello, the surge of floodwater spread out in downstream
farm fields and lost most of its punch before arriving about
three hours later in Hopkinton.
Delaware County Sheriff John LeClere said an Iowa State
Patrol pilot watching the swollen Maquoketa River reported
that the water spread into river bottoms along Pioneer Road.
“To my knowledge, there’ve been no injuries, which is the
main thing,” LeClere said.
At 3:30 p.m., Hopkinton Fire Chief Craig Wilson estimated
that the river had risen 18 inches in three hours. But many of
the homes closest to the river were still not in danger, he
said. A few miles north of town, firefighters reported to
Wilson around 4 p.m. that the water was starting to recede.
Monticello officials warned residents of low-lying
neighborhoods to expect a big rise in the river, but no
mandatory evacuation orders were issued. With the surge
dissipating over thousands of acres of farmland, worries
eased, and Monticello Police Sgt. Britt Smith, the
department’s acting chief, warned against “rumors you’re
hearing about a tidal wave, a tsunami, or anything like that.”
“The local officials seem to be doing a great job getting
people out of harm’s way,” said Gov. Chet Culver, at an
improvised command post in Monticello.
Culver issued a disaster proclamation for Delaware and
Jones counties that allows use of state resources to deal with
damage caused by the recent flash flooding.
Culver, who also activated the Iowa National Guard, said
assessment teams were in Monticello, Delhi, and points between
Saturday afternoon.
The Maquoketa had been expected to crest in Manchester on
Friday evening at 22.5 feet before another round of heavy
rains fell on its watershed. It finally crested there at a
record 24.53 feet about 12:30 p.m. Saturday, according to Jack
Klaus, a spokesman for Delaware County Emergency Management.
More than a dozen downtown businesses sustained heavy
damage as floodwaters filled them to depths of several feet.
The dam breach lowered Lake Delhi by as much as 10 feet in
a few hours, bringing some relief to the scores of lake
residents whose homes sustained first-floor flooding.
The Freddy’s Beach area, where homes sit not far above the
lake level, was among the hardest hit.
“I never, ever expected anything like this,” said Dorothy
Thomas, 85, who with her husband Fred founded the Freddy’s
Beach resort area in the 1950s.
For the first time in her 60 years on the lake, floodwaters
forced her from her home about 1:30 a.m. Saturday, she said.
Cedar Rapids resident Mike Reutzel, whose weekend cottage
flooded for the first time in his 30 years on the lake, said
the experience reminds him of the 2008 Cedar Rapids flood,
which damaged his home and business.
“We had a lot of rain on top of a record crest,” he said.
The Lake Delhi dam was last fully inspected by the
Department of Natural Resources in May of 2009 Although a few
minor repairs were still needed following the flooding of
2008, no major structural problems were found on the dam, said
Lori McDaniel, supervisor of the DNR’s flood plain and dam
safety section.
Jim Willey, president of the Lake Delhi Recreation
Association, said it will take a lot of time and effort, but
the dam will be rebuilt.
Downstream, a record crest of nearly 35 feet — 11 above
flood stage — is expected late this afternoon at Maquoketa.
That’s enough to top the levee protecting the industrial
section at the north end of town, according to the National
Weather Service.
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