Pond Boss Forums AERATION Systems questions waterfall question

Hello,

If I want to build a waterfall and get the water from my pond up a hose (PVC pipe?) at least8 feet high before dispersing the water would a pump that pumps 8200 gallons per hour do the trick? I know I have seen all the calculations on how to do this but I am math challenged.
Thanks

2 questions:
How wide do you want the waterfall to be?

Is that 8200 gph at the 8' head height or at 0'?

I had my contractor (when he was building my other pond) to dump a pile of dirt about 7 yards long and about 5 ft high as my original base. so I would have my pipes going up at least 6 ft and a width of ..I am thinking about 3ft.

I think you'll have more than enough flow with that GPH. When I was researching for my waterfall/stream, I ran across the figure of 100-150 gph per inch of waterfall width, depending on the depth of water you want in the waterfall. The general rule that I saw was circulate 50% of the water volume in the pond once an hour as a minimum figure.

You going to use 3" or 4" pipe to move the water?

Head and friction must be considered. Use the biggest pipe (within reason) that you can coming from the pump. For instance, I have a small pump that does 4,000 GPH at 0' head, but only 220 GPH at 10' head.... and that is assuming ZERO friction.

If you are going for a smooth ledge type waterfall that is perfectly level, you can pump very little water and get the desired results because the depth of the water going over the fall can be quite low (maybe a quarter of an inch or less). For something more varied, you'll need more flow, or it'll appear to be nothing more than a trickle.

When you say the biggest pipe within reason-are we talking 2 inch or bigger than that??
Thanks,
Dave

Dave to give you an idea of the amount of water here is a pic of our waterfall. It uses a 1 1/2 hp 3000 gph sprinkler pump. The head is about 6 or greater when the pond is down. It fills a stream that is about 2 ft wide and 8 feet long before it drops over the edge. I'm using 1 1/2 polly pipe the size that the pump inlet and outlet is designed for and have it plumbed to a 1 inch manifold made from pvc that spreads the water out at the outlet of the falls. I think with the pump you are using assuming it is not to far from the pond or water fall should do a great job with what you are trying to do. That is unless you want a very massive amount of water. As pointed out above the most important thing in water fall design is to get the rocks set level so the water will spread and cover the entire ledge as it drops to the next.


You can see a short clip of it in the second video in this thread and hear the sound of it.
http://www.pondboss.com/forums/ubbthreads.php?ubb=showflat&Main=13785&Number=168922#Post168922

Good luck and please post pic's when you are done. I love building water falls I have dreams of building more in the future but to many irons in the fire for now.

Dave - It depends on the amount of water the pump moves as well as the distance it will be moving it, but I tend to go about twice the size of what the pump's outlet pipe is when doing runs between 12 and 16 feet or so. Also, design the system so you have as few turns/corners in the pipe as possible.

To maximize the "look" and sound of lots of water, you'll want to do very level ledges, not a variable cobble type fall (see rockytopper's pic above and note how it is a series of ledges). It's not really a single waterfall, but rather a series of very small waterfalls, one after the other.

Thanks for the info. I really love the looks of that waterfall. Nice Job! Can you guys tell me the difference between a submerged pump and one out of the water (other than the obvious) and what do you recommend?
Thanks.

A submerged pump generally means an electric cord is run into the water. The pump is submerged and at the intake. I can't speak to how safe they are or not. But if I was going to be swimming in the pond I would avoid it. You can use a sprinkler type pump and put a check valve with screen on the intake which keeps the pump primed. Attach a float or build a stand to keep the inlet off the bottom and prevent it from sucking mud.

Dave - A submerged pump will run cooler, quieter and more efficiently. Regardless of what type (submerged or not), hook it to a GFI and give the GFI a semi-annual inspection and reset test to be on the safe side.

I prefer an external pump. Electricity is away from the water and they are easier to service when the time comes. They are noisier, but it depends on where you will locate it.

You will probably want a high volume, low head pump. Pay particular attention to the plumbing details to keep friction at a minimum. Look to some of the koi groups to see how those guys do it. They use long sweep ells for bends or heat the pipe and bend it for a custom job. Calculate the desired flow, head and friction and match the pump curve to the job. It will save you lots in electrical costs if you plan on running the falls alot.

Koiphen.com has a forum dedicated to building those colored carp ponds. Look in their Pond Construction and Filtration forum. You might want to take a look at "Pond Plumbing Primer Version 2". It has a pretty good explaination of the basics along with some pump curves.
http://www.koiphen.com/forums/showthread.php?t=48919

Thanks Tejas... Great info!

For every foot of waterfall width, one will require 1500 gph for a 1/2 to 3/4" depth water fall.

Yes, head pressure, pipe lenght, elbows, tees etc. all take in effect to how the pump will run and what is required.

We have a pump calculator for waterfalls on our web site for an easy way of calculating this. See my signature for the web page.

I have built for a customer a 35 foot long, 35 foot high water fall that used a 5000 gph pump (3/4 hp) and a 2" flexible PVC Pipe. It does a great job and is on its 4th year running.

Happy ponding!

The pictures of some of those waterfalls on your website are impressive! I don't even want to imagine how expensive some of those waterfalls were to construct... Absolutely incredible! Some of those waterfalls, go beyond waterfall and into miniature streams... You could raise trout in them if the water kept cool enough!