Lake Champlain Bridge closed

[Craig]

The rusting bridge was closed indefinitely on Oct. 16 after inspectors discovered that the deterioration of at least two of the 80-year-old concrete piers raised the threat of imminent collapse.

What's a peakbagger to do.

I noticed on my way back from NY on labor day weekend the bridge was down to one lane with stop lights on either end. I figured recovery money was being spent on repairing the decrepit bridge.

The closure is obviously a nightmare for local folks, on either side of the lake, but what about folks heading to/from the Whites to the Dacks? Has anyone found a decent workaround for this winter?

Some lakeside residents said they would be willing to take risks - including using the now barricaded bridge. Robert Smith, who since 1966 has owned Chimney Point Farm in Addison, is one of them.

Obviously this is illegal, but are local official turning a blind eye? One would presume access will be maintained for emergency transportation?

 

[beverly]

Ferry service

The Charlotte-Essex ferry has expanded its service, although it hasn't announced the winter schedule yet. It runs through the winter - depending on ice - but I'll bet they'll be sure to keep the channel open this year.

http://www.ferries.com/south_schedule.asp

It's a very sad situation for the folks that need that bridge every day

 

[Kevin Rooney]

This story got picked up on National NPR, and the story mostly focused on the lady who owns the restaurant at the end of the bridge on the VT. Apparently the emergency plan is to expand the Champlain Ferry, and use their big ice-breaker to make sure the channel stays open.

From the news story, the failure of the bridge was abrupt - while inspected regularly, it quickly deteriorated to the point of being unsafe. Both states were caught off-guard, and did realize how many thousands of cars used the bridge every day - apparently NY'ers working in VT more than the other way around.

And of course, the hiker traffic ...

It's a neat bridge, and I've used it at least 100 times over the years. Hope they rebuild something with similar charm.

 

[beverly]

It's a neat bridge, and I've used it at least 100 times over the years. Hope they rebuild something with similar charm.

Love the bridge - hate the speed traps on the NY side!

 

[beverly]

Latest news

The bridge can't be fixed - it needs to be replaced. They are going to set up a free ferry service nearby as soon as feasible.

The Charlotte-Essex Ferry is now free for the time being.

 

[bryan]

another driving route that i've taken to the high peaks area from southeastern nh that avoids the bridge all together is (assuming you've gotten to I 89):

rt. 4 through woodstock/rutland (exit 1 on 89)
to ny 22
to ny 74
to I 87 N.

from 87 you can exit where ever you like to access upper works, keene valley, etc. i found with an early morning start this route was about as fast as driving farther up I 89 and taking the bridge (i've never used the ferry). later in the day this route goes through areas with higher traffic so it may be slow where it goes through vermont in particular. i come from the rochester area, but it would probably be about the same from manchester, concord and other southern parts of nh. from the north it's probably not as desirable and the ferry would likely be the best bet.
bummer about the bridge. it's awful to think of how it's effecting the local folks that depended on it. when i crossed in september i was assuming some sort of routine maintenance was going on.

bryan

 

[Craig]

Thanks Byan,

Interesting enough the draft safety assessment report from the design consultant for the Lake Champlain Bridge Project indicates the pier footings are made of unreinforced concrete that has significantly deteriorated above and below water line.

It appears that static ice pressure exerted by thawing ice on the piers closest to the shoreline has resulted in the formation of large cracks roughly 8 to 10 ft below the water surface. The lack of reinforcement results in large cracks which exceed 3/8” in many cases.

D’oh – original design consultant from the south? (sorry, couldn’t help it)

 

[DrJJFate]

http://www.boston.com/news/local/vermont/articles/2009/11/10/champlain_bridge_cant_be_saved/

Full rebuild is in order. They are working to establish a ferry service at or very near this location.

 

[Puma concolor]

... and if you are going from the Capital Region of NY to Vermont, Route 4 is also clearly the way to go. I-87 to either Exit 17 or 20. If Exit 17, take Route 197 East to Route 4 North; if Exit 20, take Route 149 East to Route 4 North. At Whitehall, head east on Route 4 into Vermont. Depending on where you are going from there, you can take Route 22A (Exit 2 on Route 4) north to Route 7 and continue north; Route 7 north from Rutland; or Route 100 North from just east of Killington.

 

[Craig]

Based upon the HNTB - Draft Safety Assessment Report , it appears they are very concerned with the bridge spontaneously collapsing this winter.

They have completed the installation of censors on the concrete piers that will stream movement information back to the visitors center.

They are recommending no boating traffic or ice fishing within 200' of the centerline of the bridge.

The report also slaps the original design engineer for not reinforcing the concrete piers, installing ice deflection and for the way the concrete was placed in the caissons.

I wonder if someone will aim a web cam on the bridge to try and capture it's demise.

Latest news and updates can be found here.

 

[DrJJFate]

I wonder if someone will aim a web cam on the bridge to try and capture it's demise.

Tie an alarm clock to it and we could have the very first "Bridge Out". Guesses anyone?

 

[smitty77]

The report also slaps the original design engineer for not reinforcing the concrete piers, installing ice deflection and for the way the concrete was placed in the caissons.

I know the bridge was constructed in '29, but reinforced concrete is certainly nothing new. A quick search points to it's use some 30 years earlier at the turn of the century. I'm shocked that is was not used in the caissons, but maybe it was not feasible at that time? I shudder to think what would have happened to that bridge during a seismic event. Granted quakes are small in this area, but if they're worried about spontaneous collapes due to ice movements.....

 

[MichaelJ]

A lot of aspects of bridge design have been learned the hard way over the years. A skinny profile with a flexible deck turned into the Tacoma Narrows collapse. Scour, which seems so obvious, undermined the piers of the Schoharie Creek Bridge and taught us when to use piles instead of gravity footings.

While reinforced concrete did exist back then, it wasn't necessarily used or the need for it understood. In fact, concrete itself back then was different than it is now - different proportions of sand, gravel, and clay, different types of clay, different methods for curing, etc. Moreover, the lack of reinforcement is not the only problem here. Apparently the bearings (where the steel bridge superstructure sits on the concrete piers) have seized up. This means that as the bridge flexes due to heating and cooling of the steel, instead of moving as it should, it's been forcing the piers to move back and forth with it. So these piers have been impacted both by ice pressures below and the bridge itself above.

That's not to say reinforced concrete wouldn't have helped. It would be holding those cracks together and the risk of catastrophic failure a lot less. It could even have been possible to safely rehabilitate such piers. But given what I've read in the reports, this poor bridge is toast. Hopefully these people don't file lawsuits and screw it up for the locals who need a working bridge in place. Note that there's no way the bridge could be open while being rehabilitated. In fact, the recommendation against rehabilitation is because it's too unstable to be safely worked on. And really, they need to get it torn down before the ice season starts because if it comes down on its own midwinter it will be a big mess, especially if there's an icebreaker ferry running at the time.

I would not expect to see a truss bridge replacement. Modern bridge construction can easily reach the spans (and heights) necessary using less aesthetic (but equally less complicated & less difficult to maintain) designs such as steel or concrete box girders.

 

[Craig]

I was hoping we would hear from a -------- .

Apparently there was a discussion of some aspects of the original design based upon the engineers paper “Lake Champlain Bridge” published at that time.

Question to engineer:

special precautions in protecting the surface of the piers at the waterline to take care of ice pressure and wear during the winter seasons… undoubtedly, this item was considered in the design, and the omission of special protection for the concrete must have resulted from definite reasons. It would be interesting to have those auguments on records.

Answer by engineer:

the reason for not protecting the pier concrete against abrasion and deterioration, it may be pointed out that the piers are in a fresh-water lake with little current and are practically free from danger of abrasion from ice and floating objects”.

These quotes are taken out of context but gives a flavor for the (how shall I say this) mind set at the time.

Anyway, it appears that the State of NY is providing full disclosure on this issue. It’ll be interesting to see what additional information developes.

- Your average joe blow (trying to understand)

 

[MichaelJ]

Okay, so, the bridge isn't going to be dealing with moving chunks of ice like a river, no huge melt-out with fast currents in the spring, etc. I can buy that somewhat, but don't they say somewhere that this part of the lake freezes over completely in the winter? That big sheet of ice is going to exert plenty of pressure and force. It won't be swift-moving when it does so, but it's going to happen. I wonder why the limited insight at the time...

Still, I'm inclined to blame the frozen (stuck fast, not cold) bearings rocking the piers back and forth more than the ice.

 

[TCD]

News today is that new bridge will take 22 months, cost 67 million.

Add to that the cost of the bridge being out (businesses closing, people out of work, etc.).

Ouch.

Too bad the issues with the bridge (bearings, etc.) were not picked up in inspections earlier. There must have been a point, maybe some years ago, where this bridge would have been repairable.

TCD

 

[RoySwkr]

Surely it is possible to renovate the existing bridge, but it would be hazardous and expensive and you'd be left with what is basically an 80-year-old bridge. Most bridges of that era have either been removed or converted to non-vehicle use. It is not surprising that the states prefer a new bridge which is probably wider and designed for heavier loads.

An alternate location for the new bridge was rejected because it would put one of the ferry operators out of business, according to an e-mail I received.

 

[Craig]

They have not disclosed (that I saw) the method of connection from the caissons to the pier platform. Without rebar and assuming the concrete was not placed monolithically, that could be a huge weak point.

It’s interesting to note that the bridge opened the same year of the start of the great depression.
I’m wondering if the economic excesses that led up to the great depression had an influence on monetary spending in construction project of that timeframe. How’s that for a WAG?

It should be noted that the current design consultant indicated that structures of this type, typically have a 75 year life span. This bridge is 80yo.

 

[DougPaul]

Okay, so, the bridge isn't going to be dealing with moving chunks of ice like a river, no huge melt-out with fast currents in the spring, etc. I can buy that somewhat, but don't they say somewhere that this part of the lake freezes over completely in the winter? That big sheet of ice is going to exert plenty of pressure and force. It won't be swift-moving when it does so, but it's going to happen. I wonder why the limited insight at the time...

I have certainly seen the effects of ice pressure on the shores of Lake George. Wind can also exert a significant amount of pressure on the ice which would be transmitted to whatever this ice is pressed against.

Still, I'm inclined to blame the frozen (stuck fast, not cold) bearings rocking the piers back and forth more than the ice.

Concrete is strong in compression but weak in tension. (Thus the modern use of prestressing (compression).) I have no idea whether lake ice or stuck bearings is more damaging, but ice has another mechanism--frost cracking (water freezes in cracks and expands with great force). And if salt was used on the bridge, it could have damaged both concrete and steel.

Doug

 

[Kevin Rooney]

On the forces of ice ...

I'm not an engineer, but will add this -

I've seen years when Lake Champlain was completely frozen over, shore to shore, and have it open up entirely within a 24 hour period due to heavy winds. I've been told that's not uncommon given the length/width of the lake and the prevailing winds.

So, while there's no current in the lake similar to a river, when there's rapid ice break-up the force of those chunks of ice would be substantial.