At 63 years old, Mt. Morris Dam isn’t getting any younger. And for a piece of infrastructure that was only built to last 50 years, the dam has surpassed its life expectancy.
Situated deep in the Genesee River gorge, the picturesque structure is made up of over 750,000 cubic yards of concrete. Its one and only job is to control river flows that may flood and cause property damage to Rochester and surrounding cities.
Since the U.S. Army Corps of Engineers (USACE) built it in 1952, the dam has prevented over $2 billion worth of flood damages. The most recent event happened just a few weeks ago.
“We had about a 100-feet-deep lake back behind the dam. It was caused from snow melt and spring rains on top of that, and we’ve since successfully been able to pass that water downstream and provide ourselves with full storage capacity once again,” says Steve Winslow, the manager of Mt. Morris Dam.
(Video after the jump.)
The Corps of Engineers takes its dam safety responsibilities seriously and has instituted a regime to make sure that Mt. Morris Dam stays in tip-top shape. It is monitored daily and annually. And in mid-May, a multi-disciplinary team of engineers from two divisions performed a 5-year periodic inspection that was especially thorough.
“We have kind of a suite of instruments through the dam. Things that tell us if any cracks are developing, if there’s any tilt or movement of the dam on any axis, that tell us about the water pressure going underneath the dam and around the sides,” explains Winslow.
High Hazard, Low Funds
In 2013 there were 84,000 dams in the United States, according to figures from the American Society of Civil Engineers (ASCE). By 2020, 70% of those dams will be over 50 years old.
"Even though it's in the budget, they have to cut loose the appropriation - and that's what we're waiting for, really."
With an increasing population and growing development downstream, the number of high hazard dams is also on the rise. New York State has more than 400 of them, including Mt. Morris.
“It's classified a high hazard dam because there would be some devastation should it fail. It doesn’t mean that it’s in any danger of failing. High hazard is all about what’s downstream in the unlikely event that there is a problem,” says Water Resources Engineer, Tiphaine Ketch, who works for the firm Erdman Anthony.
But, around 2,000 of the nation’s high hazard dams are deficient. The Association of State Dam Safety Officials estimates that it will require an investment of $21 billion to repair these aging, yet critical, high hazard dams.
In 2013, New York State’s overall dam safety budget was $1.3 million and Ketch says that’s not nearly enough.
“There are a lot of dams in New York State that are owned by little private entities. When are they going to get their money to make sure that they’re staying on top of their dam maintenance activities?”
Experts say infrastructure funding levels have dropped dramatically over the years, with dam work seemingly low on the priority list. Even with the benefit of government funding, the tight squeeze is also felt by the USACE.
“Other than budget requests, we’re basically at the beckon call of Congress. Even though it’s in the budget, they have to cut loose the appropriation – and that’s what we’re waiting for really, is appropriations,” says the Corps’ Dam Safety Program Manager, Carm Marranca.
Inspection Findings
The dam's concrete got high marks from inspectors, who say so far, there are no red flags in terms of its security. They give the dam a four out of five.
“Everything looks very, very good. The structure is sound. There’s no cause for immediate concern at this time,” says Marranca.
Some parts of the dam, however, are going through rehabilitation for the first time since it was built. Typically only brand new structures get a five, because they are compliant with all core guidance and criteria. Those were different back in the day when Mt. Morris Dam was designed, but Marranca says it doesn’t mean that we can’t retrofit and rehab and eventually get there.
The engineers recommend that staff continue to cycle through various different machinery to open and close the gates that let the flow through. They have also been asked to keep the sump pump pit in good condition. If any water seeps through the drainage system into the dam itself or if there’s any leakage around the gates, the pump is designed to periodically remove water from the pit to ensure that it does not overflow.
Meanwhile, Mt. Morris Dam continues to perform the mission it was set out to do.
“It’s not gonna fail in the next 2 or 3 years that we know of. It’s pretty secure.”
https://www.youtube.com/watch?v=laaqzZZa3ao
