http://www.wcax.com/story/15422372/how-dams-saved-some-vt-communities
North Springfield, Vermont - September 8, 2011
Many in the Green Mountain State are comparing the destruction caused by Tropical Storm Irene to the flood of 1927.
"The parallel is that it is significantly impacting the state today as it did then," said Chris Cole of the Vt. Agency of Transportation.
The flood of 1927 killed 85 people, 9,000 lost their homes and 1,200 bridges were destroyed. Numbers from this storm are still being calculated, but are expected to be much lower. Part of the reason-- flood control dams like the one on the Black River in North Springfield.
"They hit it on the head. They did what they were designed to do," said Tom Snow of the Army Corps of Engineers.
A number of dams were built across the state following a number of catastrophic floods in the early 1900s. The dam held back 80 feet of water during Tropical Storm Irene. Downtown Springfield is just five miles away. Only minor flooding problems were reported because the dam was in place.
"The pool raised faster than ever, 4 and a half feet an hour," Snow said. "It probably would have been comparable to the '27 flood, and that was 8 feet in the Gear Shaper Building downtown."
The Army Corps of Engineers says the dams don't control flooding but minimize it.
"Ball Mountain and Townshend were a little bit higher, but the same thing happened there; they prevented a lot of damage downstream. Jamaica got a lot of damage anyway, but they would have seen a catastrophic amount of damage if it wasn't for the dam," Snow said.
"We need to take lessons learned from this flood and incorporate it into our bridge design so our investments last," Cole said.
Just like the great flood in 1927, the damage to infrastructure across the state will take years to rebuild. One lesson then-- old covered bridges were replaced with higher, steel bridges. Bridge heights will also be re-examined this time among other things.
"The bridges may need to be longer. When you have that much water fitting through a narrow opening, and when it doesn't fit, it is going to go around and over and that's when you lose bridges," Cole said.
Culverts will also be built the full length of the creeks they cross. But one problem will be difficult to get around; a number of roads close to rivers and streams were washed away. The Agency of Transportation says the only option there may be diverting the river.
"We are a mountain state. We have rivers and they move fast. There is limited place for roadways to go, we go through the gaps. What was there first? A river," Cole said.
Inspections after Irene found the state dams are in good condition. The rebuilding plan now does not call for any new dams because of the cost and because there are already dams where they are most needed.
Matt Henson - WCAX News
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