Trees on dams are a high-risk danger

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As co-founder of the Erie Canal Neighbors Association, I must respond to Ginny Maier’s June 21 article (“Trees belong on the Erie Canal”).

Michael Caswell

It’s important to understand that only some sections of the Erie Canal Trail are on raised earthen embankment dams. At these points, the prime objective is to allow vehicular traffic to inspect, maintain and rapidly repair the embankment in the event of a breach. The use by pedestrians and bikers will always be secondary to that aim. 

Public safety first, scenic charm second—always.

Safety is paramount to those living under these dams. The prime reason? These are high-hazard dams, and inspections are deemed impossible to complete because of excessive vegetative growth (see Paul C. Rizzo Engineering’s inspection reports). The New York Power Authority is simply trying to comply with the law.

Currently, maintenance is impossible. See this video from the Association of State Dam Safety Officials. 

The NYPA  Embankment Remediation Program is designed to restore the badly constructed, 100-year-old dams to a safe condition as per Federal Emergency Management Agency and U.S. Army Corps of Engineers specifications, which call for making the slope more gentle to prevent slides, fill gouges, eliminate rodent burrows, and remove root-balls that can pipe water and cause a breach. To do this, all the vegetation has to be removed, as the Canal Corp. has explained. (For more details, see this Canal Corp. informational video.)

The large percentage of trees along the canal trail are cottonwoods, all at end of life and weak-limbed. Crashing branches are commonplace, another huge safety problem. Look up the next time you are walking along the trail and imagine the injury if one of these large, overhanging limbs fell.

The ERP program is planting low-maintenance vegetation like grass and ground-covering flowering plants, to ensure that inspections can be easily carried out using walkers and drones. The Canal Corp. has proven in Brockport and Orleans county that they can produce a viable, effective and pleasant trail on a dam, while maintaining the complete safety of residents. Off the dams, there are also new trails that will be a huge improvement, especially for bikers. In the end we need safe dams, which give us safe trails.

Perinton is designated a Trail Town USA, so there are plenty of other trails available that are NOT on earthen embankment dams, so if visitors want shade and trees, they should plan to use these areas, rather than the Erie Canal Trail. 

Again, the emphasis must be safety as thousands of people currently live under the threat of a dam breach along the Erie Canal. It is unreasonable for people who do not live under this threat to be pressuring against other folks’ safety. They really have no skin in the game.

A major problem with the evidence presented by those opposing the ERP work is that they are using documentation provided by experts, but their information is regarding levees, and not earthen embankment dams. The difference is profound! EEDs hold back water permanently; levees only contain water in time of flood. 

There is tremendous pressure from water held back by an EED when filled.

The opposition group, led by Ginny Maier, engaged a hydrology expert, Dave Rosgen, to confirm that trees were beneficial on levees, which he did. When I confronted Rosgen and explained that the group were discussing EEDs on the Erie Canal, he immediately recanted his statement, writing: “It is my opinion that in this matter, the trees present a high risk related to mass wasting processes due to the saturation of fill embankments and water stages that are raised higher than the surrounding original floodplains.”

In layman’s terms, trees on dams are a high-risk danger to those living below.

The three towns of Brighton, Pittsford and Perinton seem to have ignored the fact they have allowed buildings to be constructed in a dam hazard zone (see this Association of State Dam Safety Officials explanation) for far too many years. Perhaps this is why they’d prefer to regard these dams as parks and trails? There is no emergency action plan, in the event of a breach, so there is no way to set the wheels in motion for rescue of victims etc. 

Vigilance must be rigorous, and any romantic notions of trees, shade and so on must be set aside on these currently badly maintained, potential killer dams. We should all be supporting the Canal Embankment Rehabilitation Program and welcome the fact that the new owner of the Erie Canal—the Power Authority—takes the safety of the public very seriously. It’s been a long time coming, and isn’t that hard to see, with open eyes.

Michael Caswell is co-founder of the Erie Canal Neighbors Association.

5 thoughts on “Trees on dams are a high-risk danger

  1. To call what contains the Erie Canal an earthen embankment dam is a bit of an oversimplification. This term is typically used for reservoirs where the dam is acting as a kind of choke point, holding back substantial volumes of water. In these scenarios, the ratio of dam area to reservoir volume is very small. With the Erie Canal, which functions more like a river than a reservoir, the area to volume ratio is much greater. I think this distinction is important because when the author mentions earthen dam breach, most people would associate this with a catastrophe such as the Teton Dam failure. An Erie Canal breach poses a very low risk to human well-being and instead repair costs would be more of a concern. I am not necessarily saying that the trees should stay, but I am saying that calling for their removal because of concerns over “public safety” is a big stretch.

  2. Jacob,

    Are you a dam engineer? I think not, because you obviously have not done any calculations regarding the volume of water being held back by these dams…about 47 million gallons per mile. Water on a dam exerts hydraulic pressure which is constant at any given point regardless of surface area. It only takes one small hole to create a giant flood.

    The NY Canal Corp has stated these Erie dams are unsafe, so has their new owner, NYPA…who also owns many other dams across the State. They have used recent dam engineer’ reports saying many of these embankments are at HIGH RISK, with a potential for catastrophic flood. What data did you use to make your determination that risk was “mimimal”?

    Is your statement about Dam Safety just a “hunch or feeling” like so many people seem to be saying these days? Maybe more importantly, do you yourself live above or below the waterline of the canal? Many people living out of danger seems to think they can decide how safe the Erie Canal is for those living below these unsafe dams, are you one of those folks?

    The volume of water DIRECTLY above Fairport is, well over 200,000,000 gallons and it is raised over 50 feet higher than surrounding areas. Were a canal embankment have a breach here, that water would flood many neighborhoods, not a big stretch at all to imagine that, water does runs downhill. Or is that “not likely” either?

    This embankment failed once before with a woodchuck breach at Oxbow Lake and a canal boat was found half a mile away, up in a tree. At that time, there was little construction & few buildings in the lowland area. There was only 1/3 of the water amount inside the canal at that time, a flood today would be MUCH worse simply due to more water.

    Today, that is a completely different situation, with thousands of properties under threat. Again, how did YOU determine these people, and their homes, are “safe” when the Canal folks have not? Trees on earthen dams cause safety issues if left unattended, it’s very simple really.

    Fairport’s embankment is a long, large dam, actually a series of them, broken up by the groins of the roads that intersect the canal. These will help limit how wide a breach can become if a leak starts. More importantly though, is where the Barge Canal flood gates are located , the closest is the Flood Gate at Bushnell’s Basin. The next is in Macedon at the lock there. That means ALL of the water in between the two flood control gates can flood Fairport, about 11 miles worth, so well over 500 million gallons of water will release before the Canal Corp can drop those floodgates.

    One hole would release all that water in a raging torrent… downhill.

    Low risk to human life? Repair costs more of a concern? You are way off base Sir, our neighbor’s safety should be more important than any cost to insure that safety, don’t you agree?

  3. For the past year Mike Caswell & the ECNA have presented pages & pages of data regarding safety along the Erie Canal, in particular SAFETY of the embankments that are used to create this man-made waterway. It is not a natural river so rules that some people are trying to apply about riverbanks and hillsides really don’t apply… these are earthen dams, they ALREADY have a whole set of rules to follow that work quite well.

    The ECNA safety message, the same one that both the NY Power Authority & the Canal Corporation have stated in several public meetings, hasn’t changed. This association has managed to walk that thin line between public safety & public fear, trying to state the safety issues along with explaining the process to make the Erie Canal Dams safe again. But few seem interested in discussing safety, maybe because there is NO argument that would be acceptable to keep New York Canals unsafe, none at all.

    Other’s around Rochester, especially in Fairport, have talked about trees, shade, aesthetic beauty, even oxygen levels. It seems like every possible topic has been mentioned but the MOST important, that is safety. And now someone is trying to open up another topic that says we shouldn’t “pay too much” to insure the safety of those folks living below and working along the Erie Canal. Really?

    As one of those people living and working DAILY on the Erie Canal I’m offended by the insensitivity of folks like Jacob to Erie Canal neighbor’s safety issues. If the OWNERS of the NY Canal System say the canal has reached the point of being a safety concern, who are we to argue that? If the caretakers of the Erie Canal says that have a way to remedy the problem who are we to throw stones at that plan? There is a problem that needs to be fixed and the Canal Corp is working through that, why would anyone want to fight against safety?

    The NY Power Authority has stated that residents & communities along the Erie Canal are at risk of potential flooding due to unsafe conditions of their flood control structures, earthen embankment dams to be specific. And now some people want to change the topic to what the “financial cost” might be to insure safety for our friends & families.

    Shame on us ALL if we go down that road.

  4. No one on this page is a dam engineer. That does not mean we aren’t smart educated people able to formulate articulate questions about what is being done in our community. Name calling and other forms of intimidation do not further the discussion. The fact remains that we took NYPA to court for an over zealous embankment plan and for not engaging the concerned citizens in an open period of voiced public opinion as per the State Environmental Quality Review Act. (SEQRA) The court ruled NYPA was in violation. All worked stopped. Not in time to give the residents and canal lovers and business owners on the westside of Monroe County and the eastside of Orleans County a chance to fight. The damage was done. The conversation continues to circle around the danger of trees on the canal embankments, meanwhile, the actual and documented causes of canal breeches is the work that is done around the many culverts that go under the canal. Many of these culverts are old, damaged and in need of repair. Some of these culverts are not on NYPA maps. Instead NYPA is focusing on trees, because they contend the trees could potentially at some point cause a breech… even though in 200 years they have not. Why not focus attention on what NYPA is actually qualified to assess, and that is the health of the dams, locks and culverts along the canal? Why they decided to overlook these worn out man made structures and focus instead on trees, seems odd and capricious.

  5. I appreciate that not everyone puts the same value on trees and natural landscapes as I do, but I do wish to reiterate that one can love the natural world AND care very much about the safety and well-being of neighbors along the Canal. My evaluation of all of the information available about current identified risks, historical canal breaches, and the lack of evidence that trees growing on — yes, even on dams! — have caused the kind of catastrophic problem that the Canal Corporation’s tree removal plan is supposed to be protecting us from gives me confidence that a plan that preserves the naturalistic canal embankments can be safe for those living along the Canal. All we are asking for is a public process that could help to create this management plan — one that includes input from dam engineers, environmentalists, plant biologists, trail uses, and neighbors — so that all who value this amazing, unique, historic structure can make a thoughtful and well-informed decision. This is not a radical thing to ask for, and as citizens, we should be asking for it.

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