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Posted by: Doug K
« on: July 20, 2021, 04:08:47 pm »

And I was remiss in NOT answering Ms. Maier's question... "Where did this statement come from?"

That STATEMENT, about tree roots "stabilizing soil" being a myth, and the exact opposite of the truth that tree roots "loosen soil",  is found in a FEMA Technical Manual for Dam Owners, regarding vegetation  on Dams.

Here's the website, and another FEMA Dam Owner Manual about the danger of animals on Dams

The statement is in this manual

Chapter 3

Page 3-2

And there's more "myths" that people, even smart ones may believe, it's a good read.

Of course, these two manuals contain the Science & Engineering Facts & Best Practices for Dam Owners. Those people have a vested interest in preserving public safety, and their impounded water.

The information provided may not be able to be understood by people who aren't Dam Owners, who deny dam safety issues, and don't believe anything but the "truth they tell themselves".

Normally those people just walk along the top of someone else's dam, they aren't Dam Owners, or Engineers.

Posted by: Doug K
« on: July 13, 2021, 12:51:33 pm »

This is truly amazing stuff... riveting.

And I don't want people to get the wrong idea, surely we at the ECNA would be lost at times about what to put on our Forum, if it wasn't for the antics of this Facebook Group. I'd like to thank them myself, but they won't talk to either Mike or me anymore.

Much to the satisfaction of ALL PARTIES I'm sure.

The title of my reply may seem a bit "harsh" but the truth is that a "good" Biologist, would, at a minimum, recognize & understand that she is NOT a Hydrologist, or a Geologist. And that just because you think you may be an "expert" in the "plant" part of Dam Safety Problem it doesnt mean you can ignore the other two parts.

So this time it started with this post on the Stop the Canal Clear-cut Facebook Page.

And make sure you see TWO things... One that Ms Maier did say "I made" some changes to the STCC Main Website and the other, the general highlighted comments of the only reply.

So I went to the website, just to take a look, here's the page on "Safety"...LOL.

And there's "more"... I put comments on some of the screen shots I captured.

And this was the end... it's the LIST OF REFERENCES from the EEIP Guidebook work for the SEQR Environmental Impact Statement. This list SUPPORTS the document, that supports the case to clear canal embankments. It is NOT something the STCC Leadership likes.

You can read the final statement I've made about this "myth", also the view of many members in the Erie Canal Neighbors Association, at the end of the last page below.

Just a word of advice to any fellow Erie Neighbors, be careful about believing what's been "shared" by this Facebook group.

They are still unwilling to listen to the science and facts provided to them, and almost in disbelief think their "plan" to ignore public safety in and around the Erie Canal will still work.

Ask to see EVIDENCE that what they say is TRUE, ask for FACTS, or you may also be caught up in believing their "myth" about "trees on dams".

The OWNERS of the Canal System PROVIDED EVIDENCE that those TREES are UNSAFE, from certified Embankment Dam Safety Resources

A BEEKEEPER & a BIOLOGIST who walk along the top CREST of that Dam, SAY it's all a "Myth", because "smart people" believe otherwise.

You all have a choice to believe which one is telling the truth, the property OWNERS, or a couple of their "park patrons".

Because sometimes even "smart people" are not educated in the tiny details surrounding earthen embankment dam safety... and that folks is a FACT!

Posted by: Michael Caswell
« on: July 13, 2021, 10:45:57 am »

Ms Maier shows her ignorance on dam construction.

"it is clear from the the structure of the embankments and the engineering documents of the time that they are not made of compacted earth the way a dam that creates a reservoir is.  They are piles of dirt, whose stability may, in fact, depend on the roots that form a dense network within them."

So what has Ms Maier missed here?

Hydrostatic pressure!
  The pressure exerted by a fluid at equilibrium at a given point within the fluid, due to the force of gravity. Hydrostatic pressure increases in proportion to depth measured from the surface because of the increasing weight of fluid exerting downward force from above

The water behind these dams causes hydrostatic pressure, which will FORCE water to push through the soil, following tree roots, gopher holes etc. Trees roots won't prevent this happening. The water will naturally seep through the dam, causing a phenomenon called the PHREATIC LINE, and unless careful management of this is not done, slumping of the slope can occur and catastrophic flood will ensue.

Ms Maier is STILL confused with the difference between a dam and a levee, as demonstrated by this statement.

 "The earthen Canal Embankments are not engineered dams. The first 12 pages of the Embankment Maintenance Manual are essentially a long argument that yes, they are. We disagree for a number of reasons -- the primary being that a dam is build perpendicular to flowing water; these embankments are built parallel to the "flow" of the canal. But regardless, even if you accept this premise, it is clear from the the structure of the embankments and the engineering documents of the time that they are not made of compacted earth the way a dam that creates a reservoir is.  They are piles of dirt, whose stability may, in fact, depend on the roots that form a dense network within them."

Yes, obviously a lack of knowledge here.

They called in an 'expert witness' Professor Donald Gray, but conveniently forgot to tell him they were dealing with a DAM, not a levee!

HE recanted his statement when he discovered the truth, stating, "I donít know of any earth dams where woody vegetation was purposely planted or allowed to grow on a face of the dam."

Gray explains the  difference between a levee and a dam as follows "Earth dams and levees are both constructed embankments. They differ mainly in their purpose and type of hydraulic loading.   Earth dams are constructed across a stream or river to create an impoundment. 

The impoundment provides water storage, flood control, and recreational opportunities.  An earthen levee is constructed parallel to a river or stream to prevent flooding of adjacent low-lying areas during periods of high water.  An earthen levee is subjected mainly to tangential-hydraulic forces (scour) whereas a dam is subjected to dynamic hydraulic forces (wave action)

The description of a dam here suits the canal embankment, because it is containing the flow of many streams, with hardly any tangential flow of water, unlike a levee.  This tangential flow (as in a river) will scour the embankments, so trees in this situation are good, as in a levee. But Levees aren't subject to a continual pressure of the contained water, because they are only used to contain a flood.

The hydraulic forces on a dam are mainly from the continual pressure of the water against the dam. THIS is the reason why dams are so dangerous if not correctly maintained.

Maier states - "We think it is more accurate to consider the Canal embankments as part of a unique, historic,  linear park system and make decisions about  how to maintain these embankments with that understanding."

It's now a park, not a dam!   How convenient, but it doesn't get away from the fact that this pile of dirt is under constant hydrostatic pressure.  Hundreds of millions of gallons pf water are being held back by some dirt.  And in the event of a failure, hundreds of properties and lives are at risk.   

Obviously, none of these people are hydrologists or dam engineers. And frankly, they simply do not know what they are talking about.

For a better understanding of dams, their construction and problems, please visit where you will find most of the points raised by the STCC totally disproved.