Major Water Main Break in Bowness Area

[fotze2]

Originally Posted by BlackArcher101

Not entirely sure in this case, but I imagine closing the line off to test procedures on using the remaining system and see what it could handle (compare to modelling) and test the procedure on restarting the line. In reality probably helped a lot to prepare them for this unplanned break. Website just says the following:

Ahh. I was thinking some sort of negative pressure test. But it’s like a stress test. Better than any model will tell ya.

[BlackArcher101]

Originally Posted by GGG

You look at things like that and you see how close the city was to this being a complete non-issue that no one would have known about. It gets to December water use is low the system can make up the supply we have some excavations being done and some traffic diverted and no one ever under stands what the city avoided. Instead they are 6 months late with the plan and we all get to be water experts.

Ya, I'm betting that normally they wouldn't be doing that level of inspection for a pipe at 50% of it's lifespan, but other municipalities having issue with the same type of pipe had them move that up. Unfortunately it was just short of an unexpected failure. With the install of the acoustic monitoring this year, and then a follow up robotic inspection in December, they were definitely starting to get worried but probably thought they were ahead of it.

[fotze2]

Originally Posted by GGG

You look at things like that and you see how close the city was to this being a complete non-issue that no one would have known about. It gets to December water use is low the system can make up the supply we have some excavations being done and some traffic diverted and no one ever under stands what the city avoided. Instead they are 6 months late with the plan and we all get to be water experts.

This type of thing is why I quit my current job. Recommended to inspect a line and was pushed off until next year, for the fifth year in a row. Sour gas with a lot of bad liquid near a decent sized town is n a 60 yr old line.

I bet Someone(s) at the city has an email or memo of someone pushing. Usually the gamble pays off but when it doesn’t.

I would think you could put some sort of liner in this pipe in the bad sections. Can’t imagine a small diameter reduction for 40 odd meters would make much difference.

[BlackArcher101]

Originally Posted by fotze2

I would think you could put some sort of liner in this pipe in the bad sections. Can’t imagine a small diameter reduction for 40 odd meters would make much difference.

There's definitely options. I'm sure they will look at them after the repairs are done, would be a large capital project in itself.

https://www.nwpipe.com/app/uploads/2...-Pipe-2004.pdf

More reading for the nerds: https://www.xylem.com/en-us/brands/p...der-pipe-pccp/

[fotze2]

Originally Posted by BlackArcher101

Ya, I'm betting that normally they wouldn't be doing that level of inspection for a pipe at 50% of it's lifespan, but other municipalities having issue with the same type of pipe had them move that up. Unfortunately it was just short of an unexpected failure. With the install of the acoustic monitoring this year, and then a follow up robotic inspection in December, they were definitely starting to get worried but probably thought they were ahead of it.

That 100 year life span predicted 50 years ago seems a little suspect.
A. Because it was clearly wrong.
B. based on what conditions and usage? They think we would be this big a city?
C. We weren’t quit as advanced back then.

I don’t buy any lifespan over 20 years unless it’s a pet rock or chunk of granite.

[BlackArcher101]

Originally Posted by fotze2

That 100 year life span predicted 50 years ago seems a little suspect.
A. Because it was clearly wrong.
B. based on what conditions and usage? They think we would be this big a city?
C. We weren’t quit as advanced back then.

I don’t buy any lifespan over 20 years unless it’s a pet rock or chunk of granite.

Sales promises made by big Concrete Pressure Pipe industry. I too never trust lifetime promises for new technologies, even if they come from engineers.

[fotze2]

Originally Posted by BlackArcher101

Sales promises made by big Concrete Pressure Pipe industry. I too never trust lifetime promises for new technologies, even if they come from engineers.

Especially if they come from engineers!!

This rain probably really helps repair operations! Hahah.

[GGG]

That Xylem site is pretty neat.

I wonder if you pipe was the new in 1972 class 3 or class 4 high tensile wire that led to lots of failures in the 1980s or if was made out of the older stuff

https://info.xyleminc.com/rs/198-DLL...ODMyOS4wLjAuMA..

It reads like a classic engineering failure study. Take a good working product, reduce design tolerances in areas you think you understand the failure mechanisms, then get bitten by some other not well understood mechanism that was being prevented by the “over design”.

[soreshins]

Originally Posted by BlackArcher101

Not entirely sure in this case, but I imagine closing the line off to test procedures on using the remaining system and see what it could handle (compare to modelling) and test the procedure on restarting the line. In reality probably helped a lot to prepare them for this unplanned break. Website just says the following:

I imagine they were testing to see if the in-line valves, scour/drain valves and air valves etc. were all operating properly so that they can properly shut down sections of the line when actually required for the planned condition assessment.
Sometimes the line valves can seize up if they haven’t been operated in a while and this can cause a whole other set of problems. They may also be actuated valves rather than manually operated so need to test the actuators are working etc.

[BlackArcher101]

Originally Posted by soreshins

I imagine they were testing to see if the in-line valves, scour/drain valves and air valves etc. were all operating properly so that they can properly shut down sections of the line when actually required for the planned condition assessment.
Sometimes the line valves can seize up if they haven’t been operated in a while and this can cause a whole other set of problems. They may also be actuated valves rather than manually operated so need to test the actuators are working etc.

That would explain the maintenance on the air valves around the same time.

[fotze2]

Originally Posted by BlackArcher101

That would explain the maintenance on the air valves around the same time.

Are these full bore valves or some sort of venting valves? Do these types of lines have ESD’s? What are air valves? So they can burp the line?

[soreshins]

Air rises in the pipeline and needs to be vented through air valves at the high points or it impedes flow. Also let’s air in when emptying the line. They can have problems seating properly and can pass water so that would be an issue for re-pressurizing the line after repairs.

[fotze2]

Originally Posted by soreshins

Air rises in the pipeline and needs to be vented at the high points or it impedes flow. Also let’s air in when emptying the line. They can have problems seating properly and can pass water so that would be an issue for re-pressurizing the line after repairs.

What type of pressure would these lines be at? Obvious highest at the discharge of the pumps. Or is it just gravity based. I really know nothing about these pipes obviously.

[GGG]

The household side design pressure is 100 PSI. Not sure if the mains are different.

[soreshins]

Originally Posted by fotze2

What type of pressure would these lines be at? Obvious highest at the discharge of the pumps. Or is it just gravity based. I really know nothing about these pipes obviously.

Honestly not sure as I’ve never worked with these concrete pipes but on ductile iron pipes back in the UK the test pressure was 16 bar = 230 PSI

[Sr. Mints]

I was all set to throw in the towel on my garden this year. But I managed to collect maybe two-three weeks of water today (which is backbreaking work when you've previously broken your back!)

Going forward, I want to figure out a rain barrel system that makes use of the eaves and downspouts as they're configured now (much of the house has got a french drain system I don't want to monkey with.) It's a walkout basement and the garden is in the back, so gravity is on my side.

It's surprising how much water I was able to collect in just an hour! I've never really thought about it.

[puffnstuff]

My rain barrel is full again. Plus some giant plastic tubs from the other downspouts, filled up fast too.

I read some social media comments...i know i know...but am really struggling to understand why so many of those idiots blame the WEF. It seems to be their favorite thing to blame. Oh and the mayor and all the levels government are in on it.

[burn_this_city]

I filled two rubbermaid roughneck garbage cans we had leftover from life before the black bin. Took off the downspout and hooked up a couple flex a spout extensions to fill. I'm amazed how much water runs off the roof in an average rainfall.

[PepsiFree]

Originally Posted by puffnstuff

My rain barrel is full again. Plus some giant plastic tubs from the other downspouts, filled up fast too.

I read some social media comments...i know i know...but am really struggling to understand why so many of those idiots blame the WEF. It seems to be their favorite thing to blame. Oh and the mayor and all the levels government are in on it.

They’re just asking questions. Question eVeRyThInG!!!

[Mr.Coffee]

The rain barrel thing is a pretty cool idea for sure, gonna have to try it as well