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Dep increases releases at cannonsville reservoir to facilitate necessary repairs

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Fishizzle, I use worms but I'm looking to upgrade!
viewed this today on FUDR facebook page...
i wonder how long they'll need to release???

press release link here

FOR IMMEDIATE RELEASE: July 15, 2015 CONTACT: deppressoffice@dep.nyc.gov, (718) 595-6600 No. XX DEPARTMENT OF ENVIRONMETAL PROTECTION INCREASES RELEASES AT CANNONSVILLE RESERVOIR TO FACILITATE NECESSARY REPAIRS
The New York City Department of Environmental Protection (DEP) today increased drinking water diversions and downstream releases from Cannonsville Reservoir to facilitate necessary repairs in response to an ongoing turbid discharge from a rock embankment below Cannonsville Dam. DEP, its regulators, and consulting experts do not believe the turbid flow represents any imminent threat to the safety of the dam. While repairs are made, DEP believes it is prudent to draw down the reservoir through increased releases out of an abundance of caution; reducing storage does not pose a risk to the city’s water supply. The turbid flow below the dam was discovered when workers were drilling borings in preparation for design and construction of the future hydroelectric facility to be built there. During the drilling, workers noticed a flow of turbid water coming from a rock embankment near the release chamber. They immediately contacted DEP engineers and ceased all work. A preliminary investigation indicated that the drilling released ground water under natural pressure several dozen feet below surface level, causing an upward flow of water and sediment that is reaching the West Branch Delaware River. Since then, DEP has met with its regulators, consulting engineers, and other experts to further investigate the condition, and to identify next steps for monitoring and repair. In addition to reducing storage at Cannonsville Reservoir, DEP is taking several steps to minimize any potential risks. These include 24-hour monitoring by employees at the site, regular analysis of dam-safety instrumentation, and testing of the turbid sediment to identify and understand its origin. DEP is also working with the Federal Energy Regulatory Commission and the New York State Department of Environmental Conservation on the design and implementation of repairs to stop the flow of water and sediment below Cannonsville Dam. Federal, state, county and local officials – including officials from New Jersey and Pennsylvania – have been made aware of the condition at Cannonsville Dam. These officials will be updated as DEP continues to examine and address the flow condition. DEP also plans to host a series of public meetings to further inform downstream residents in the days and weeks ahead. Details on those meetings will follow soon. Placed into service in 1964, Cannonsville Reservoir was the last of New York City’s 19 reservoirs to be built. Water drawn from Cannonsville enters the West Delaware Tunnel and travels 44 miles to the upper end of Rondout Reservoir. From there, it is carried in the 85-milelong Delaware Aqueduct. Water is released from Cannonsville Reservoir under the terms of the 1954 U.S. Supreme Court Decree, and a flow program, known as the Flexible Flow Management Program, agreed upon by New York City and the states of Delaware, New Jersey, New York and Pennsylvania. All other reservoirs in the city’s Delaware System will continue to meet their downstream release requirements under the Flexible Flow Management Program while the condition at Cannonsville is investigated and repaired. DEP manages New York City’s water supply, providing more than one billion gallons of high quality water each day to more than 9 million New Yorkers. This includes more than 70 upstate communities and institutions in Ulster, Orange, Putnam and Westchester counties who consume an average of 110 million total gallons of drinking water daily from New York City’s water supply system. This water comes from the Catskill, Delaware, and Croton watersheds that extend more than 125 miles from the City, and the system comprises 19 reservoirs, three controlled lakes, and numerous tunnels and aqueducts. DEP has nearly 6,000 employees, including almost 1,000 scientists, engineers, surveyors, watershed maintainers and other professionals in the upstate watershed. In addition to its $70 million payroll and $157 million in annual taxes paid in upstate counties, DEP has invested more than $1.7 billion in watershed protection programs—including partnership organizations such as the Catskill Watershed Corporation and the Watershed Agricultural Council—that support sustainable farming practices, environmentally sensitive economic development, and local economic opportunity. In addition, DEP has a robust capital program with nearly $14 billion in investments planned over the next 10 years that will create up to 3,000 construction-related jobs per year. For more information, visit nyc.gov/dep, like us on Facebook at facebook.com/nycwater, or follow us on Twitter at twitter.com/nycwater
 
reducing storage does not pose a risk to the city’s water supply

Can we use this quote in the future........and.....surf's up!
 
I thought the same exact thing Tompg. There is plenty of water so no risk to draw it down a bit- unless its for the health of the river of course.
 
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Of course the pending damage to the ecosystem if it is a dam leak and difficult to repair could be a big problem. I haven't heard much yet but officials are concerned as the water is silting showing signs of erosion. Is the water coming from an aquifer or from the bottom of Cannonsville? I heard it's more than a trickle 127CFS. NYC is now desperately trying to drop the water in the reservoir via max releases to the river and into the drinking water system as a precaution (for repairs if required but no doubt if the dam is leaking less water in it is not a bad thing). I heard they are going to try and jam concrete into the the flow to see if they can stop it.

They will continue to let water out of the dam until at least September 1. Depending upon rain, If 2000CFs are coming out of the dam per day, we would be down to roughly 50% to 60% full. If more is taken out, then less water in Cannonsville (not sure how much they can divert into the drinking water system). After Sept 1 who knows.

The bottom line at the moment is that they don't really know much. Let's hope for the best.
 
I'll expect an abrupt change to 120 cfs in october overnight to keep tradition alive. This could get dicey long term drawing the res down to such low levels. U don't always get a big snow year like last to help you play catch up.
 
Is the water coming from an aquifer or from the bottom of Cannonsville? I heard it's more than a trickle 127CFS.

they are basically the same thing at that point. water is driven around (below) the dam by the head pressure behind it. sounds like DEP potentially messed up by basically relieving some constraining pressures that could prove to be problematic if not effectively addressed in short order.

super simplified illustration and discussion of implications:
NPTEL Online IIT Guwahati
 
they are basically the same thing at that point. water is driven around (below) the dam by the head pressure behind it. sounds like DEP potentially messed up by basically relieving some constraining pressures that could prove to be problematic if not effectively addressed in short order.

super simplified illustration and discussion of implications:
NPTEL Online IIT Guwahati

I will say that I don't know exactly where they were drilling, and there are some (at least potentially) confined and semi-confined aquifers with (relatively) higher elevation recharge areas (ergo high potentiometric head) in the vicinity. they typically would not produce turbid flowing artesian conditions, but who knows.
 
I will say that I don't know exactly where they were drilling, and there are some (at least potentially) confined and semi-confined aquifers with (relatively) higher elevation recharge areas (ergo high potentiometric head) in the vicinity. they typically would not produce turbid flowing artesian conditions, but who knows.

Thanks... Sounds like you know something about dams.
 
What I know for sure at this point is that the plan is to draw down the Reservoir to Zero. They are emptying the Cannonsville which should be done by mid to late September.

This is not a rumor or some conspiracy theory BTW.
 
What I know for sure at this point is that the plan is to draw down the Reservoir to Zero. They are emptying the Cannonsville which should be done by mid to late September.

This is not a rumor or some conspiracy theory BTW.


The plan is to see whether the turbidity is coming from the holes they drilled or somewhere inside the dam filing. They're pretty confident it's coming from the holes, in which case, they won't empty the reservoir, but they're continuing at maximum release just to be on the safe side in case it's the worst scenario. They'll know next week.

Sounds to me like it's very unlikely that they'll empty the reservoir, and they're just being super-conservative. Hope I'm right about that.:crap:
 
I am no Civil Engineer, but I when I red this excerpt from "Proceedings of the Michigan Engineering Society" published in 1885 page 41. It was alarming.

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I am no Civil Engineer, but I when I red this excerpt from "Proceedings of the Michigan Engineering Society" published in 1885 page 41. It was alarming.

No offense Tomfly. But saying "I am no civil engineer" and then quoting a vague and obscure 130 year old source about dam troubleshooting is an exercise in redundancy.

(and I don't mean the good kind...)

I'm starting to think that you and CMM should have a sit-down and figure this whole dam thing out.
 
No offense Tomfly. But saying "I am no civil engineer" and then quoting a vague and obscure 130 year old source about dam troubleshooting is an exercise in redundancy.

(and I don't mean the good kind...)

I'm starting to think that you and CMM should have a sit-down and figure this whole dam thing out.

What is so vague about the excerpt? From what I read, the excerpt describes how unwanted hydraulic flows in the structure can transport martial through the system causing degradation of the structure. Am I correct in what I understood? The DEC states it could be ground water from the test holes. If so why is the Dam sitting on an aquifer? Wouldn’t that be a problem with the geological structure that the dam is constructed upon? That Dam has a big problem in either scenario. Perhaps the test holes presented a problem that went undetected and now can be addressed before any loss of life.

MB you should know by now, I am thick skinned and attacking me to get under my skin is a lesson in futility. AK tried it on a few occasions and failed. What did get me in a tizzy; is your problem with so call old engineering methodology. My father was a Mechanical Engineer for NASA (yea a rocket engineer) in the 60s and 70s. He would design the part go out in the machine shop and make the part. That is what he did. He did not work on the big Saturn 5 but the smaller rockets that launched the so called “weather satellites”. He had no modern computer modeling or CAD system to find problems. He used a slide ruler and his head. He had to get it correct the first time. My father used a slide ruler all his life. So don’t underestimate antiquated engineering methodology. They built most of the structures in the world, not using a Computer but using their head.

Not to get of the subject but when I was a kid Young 8-9 years old. I can remember the Cost Guard in Virginia. Their primary mission was to defend NASA’s Wallops Island facility. They did not have the typical Cutters, they had Destroyers. Every now and then the Russian fishing boats would get too close to the Island. Even at the age I knew what was going on. I would be in School and hear the Destroyers 5 inch guns singing while they lobed shells over the Russian boats. The whole school would shake when those guns were in operation. It was not like today “lets escort them away BS” They sent a message. The US had a set of balls back then .They were the good old days before The Political correct society emerged.
 
Does anyone have more details on this. I have heard 1500 cfs release from Cannonsville for 3 weeks. Is that right? I guess I won't be going for smallies anytime soon then.
 
What is so vague about the excerpt? From what I read, the excerpt describes how unwanted hydraulic flows in the structure can transport martial through the system causing degradation of the structure. Am I correct in what I understood? The DEC states it could be ground water from the test holes. If so why is the Dam sitting on an aquifer? Wouldn’t that be a problem with the geological structure that the dam is constructed upon? That Dam has a big problem in either scenario. Perhaps the test holes presented a problem that went undetected and now can be addressed before any loss of life.

MB you should know by now, I am thick skinned and attacking me to get under my skin is a lesson in futility. AK tried it on a few occasions and failed. What did get me in a tizzy; is your problem with so call old engineering methodology. My father was a Mechanical Engineer for NASA (yea a rocket engineer) in the 60s and 70s. He would design the part go out in the machine shop and make the part. That is what he did. He did not work on the big Saturn 5 but the smaller rockets that launched the so called “weather satellites”. He had no modern computer modeling or CAD system to find problems. He used a slide ruler and his head. He had to get it correct the first time. My father used a slide ruler all his life. So don’t underestimate antiquated engineering methodology. They built most of the structures in the world, not using a Computer but using their head.

Not to get of the subject but when I was a kid Young 8-9 years old. I can remember the Cost Guard in Virginia. Their primary mission was to defend NASA’s Wallops Island facility. They did not have the typical Cutters, they had Destroyers. Every now and then the Russian fishing boats would get too close to the Island. Even at the age I knew what was going on. I would be in School and hear the Destroyers 5 inch guns singing while they lobed shells over the Russian boats. The whole school would shake when those guns were in operation. It was not like today “lets escort them away BS” They sent a message. The US had a set of balls back then .They were the good old days before The Political correct society emerged.

Cool story Tom!!!

Let's go easy on mudbug. He appears to have some insecurities so he lashes out from time to time:)
 
I am sorry Tomfly. I meant no disrespect. Must have forgotten to take my estrogen.:)

I doubt that modern dam engineers consult the "Proceedings of the Michigan Engineering Society" from 1951. I suspect they rely on more recent sources. That's all I was saying.

Cool story about your dad designing rockets with a slide rule.
 
Does anyone have more details on this. I have heard 1500 cfs release from Cannonsville for 3 weeks. Is that right? I guess I won't be going for smallies anytime soon then.

Although this story changes nearly daily and who you speak with, right now the plan is to draw the reservoir down to just the river's flow which is something like 2% to 3% capacity and to have that done via the 1,500 cfs max release through about mid August. If something shows that they do not have to continue this draw down, then they will stop it and fix anything in need of repair and then refill it. Right now, everything is speculation, but the plan is a total draw down.
 
If they do total draw down in mid August, the river will be back in it's natural state..............not very good for the trout
 
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