The pipes ( two- 2" HDPE) are now in place. The pipeline has been broken into three sections, with a small pressure relief open sump at the end of each section.
But they won't be running water through the pipe until next week, so I can't yet report on how much water the system is producing.
So just an update. Due to a number of very useful comments here, we've decided not to take a chance with just using an open pipe to ensure that the waterline doesn't burst.
We also decided to use a lower intake point- which increases the waterline needed to 1500 metres, but reduces the...
Bottom Line here everyone: the pipeline WILL be built and so there WILL be an answer to my two specific original questions. For those of you kind enough to have provided some computational basis for answering the question regarding flow- thanks; it will be interesting to see what the flow will...
Again, thanks. Just finished excavating the sump for storing water- so now we just need to install the waterline!
Thanks for the ballpark estimates of flow rate using a numerical approach- always important.
Getting the top of the pipe nicely under water shouldn't be a problem- there is about...
Thanks for the reminder about firmly anchoring the pipe. The slope is generally smooth, but has some big rocks, so we should be able to anchor it fairly well.
But the big question that no one has tried to answer yet is: how much flow can I expect to get? My little iPhone Pipe Sizer app tells...
Thanks a lot everyone; very informative!
I'm not worried about any debris in the pipe that might clog it- we are tapping into the stream at the outlet of a mountain tarn, so it is crystal clear water with no chance or debris (unless some little marmot-like critter gets too close out of...
I need to bring water from a creek at about 2400 metres elevation for 1000 metres down a steep slope to a drill sump located at about 2050 metres elevation.
I'm planning to use a 2 inch HDPE open pipe for this and am trying to determine how much water this will provide, and if I need to worry...
Thanks for the suggestions- I think I have enough information now to help make a decision.
I don't think sliding lake ice down the road would work- trust me, if you saw the site, you'd understand. Would be fun, though.
We've thought about siphoning- that is definitely a possibility. We'd have to have a valve on at least one end so we can fill the pipe, and limit the head to probably somewhere less than 7 metres, which shouldn't be a problem.
I had forgotten about Canadian Dewatering- I've used them in the...
Assume a two metre discharge head- that is, I think I can keep cutting the outlet trench down so that the lake level is never more than two metres below the level of the outlet trench as it is being excavated.
BTW, thanks for all the help; this is great. If you can provide me with any rental...
Yeh- a cofferdam definitely wouldn't work- the water gets too deep too quickly as one moves offshore- we need to work from the shore out; or more specifically, from the existing outlet channel out.
It's possible that we may be able to advance the trench to the lake edge, and then slowly remove...
Yep- serious pumping efforts would be needed- I figure I need at least four, 10,000 gpm electric submersibles. Electric pumps would be desirable because they reduce the possibility of a fuel spill (even though the lake has no fish).
But I'd like to have a better idea from some of you...
Sorry, the flow withdrawal rate is 3 m3/s, not 3 m/s.
Few other points:
Water from surrounding water tables shouldn't be an issue- the lake is in a rock basin. Also, I'm not too worried about unexpected pump breakdowns or an unusual rain storm- if that happened, the lake level would rise...
Most of the trench going from the intake to the lake would be excavated before the lake would need to be lowered- so it is only the remaining rock on the lake-end of the trench that we're thinking of removing by lowering the lake level. We have thought of drilling a lake tap or just doing a...
Thanks to both of you for the info- much appreciated.
We're talking about an alpine lake in southwestern British Columbia, Canada, which is located at about 1100 metres elevation.
The idea of using a pump on a barge to minimize the head is a good one. The ultimate purpose here is to construct...
