Pondless Waterfall Build Questions

[msr0459]

Hi all,

I'm embarking on quite a waterfall build, and have two questions to those with more knowledge and experience. This is being built on a pretty steep slope, maybe 70 degrees. I plan on having two different liners. One for the basin, and one for the waterfall and stream.

How far does the liner from the stream have to go down into the basin? It seems that if it went down maybe by a couple of feet, it would ensure that the water actually goes "into" the basin, BUT would water then get under that lip of the stream liner, because it's below the top of the filled basin?

Also, I'm planning on branching off of the main stream at some point, into maybe a 1' tributary of sorts, to go around a previously planted tea olive tree, then back into the same basin. If I account for the extra "water in motion", does this seem doable? All the tutorials online show just one stream.

Thanks,
Marc

 

[Lisak1]

Not only does the stream liner need to go down into the basin, the basin liner needs to come up UNDER the stream liner. The overlap recommendation is about 12" if I'm not mistaken.

Adding a second stream is definitely a possibility - just two streams feeding one waterfall. Your basin needs to be able to hold all the water that would flow downhill if the pump were shut off. Oversized is always better than undersized, as it will also help you keep the system from needing topping off too frequently.

Your slope is indeed steep - do you have a photo you could share?

 

[GBBUDD]

The biggest problem with most waterfalls is the liner not being wide enough off to the sides. This allows water to get outside the containment and a simple splash that happens all day every day adds up quickly.

Not to offend but i have no idea what you know.

Any natural waterfall does not ride on the surface . it cuts its way into the hill side.

Any large drops can easily be caught by the wind and blow it outside containment.

Larger rocks at the drops make for whats called character stones, where it looks more natural as well eye appealing.

picture are a great help in helping us help you.

 

[GBBUDD]

 

[poconojoe]

I overlapped my bog liner about 2 feet over and into my pond and my pond liner goes about 2 feet up and under the bog liner. Never had any water escape.

If you are paranoid about it, members here have used tubes of PL-S30. You can run a bead between the liners for added protection. Its probably not neccessary, but again, if it helps you sleep at night.
It comes in tubes that fit in a caulking gun. Its polyurethane based.

 

[msr0459]

Thanks everyone. About a decade ago I did build a smaller waterfall, with about an 8' stream going into the basin. I recall a lot of what I learned from that, i.e., how to turn up the sides of liner to not allow spillage, black foaming areas, etc. I've watched just about every tutorial on YouTube at this point! Lol

I have calculated for "water in motion" with both streams. I also just measured the "rise"? From the lowest point of the ground up to where the spillway will be. I'm coming up with approximately 9'4".

Here's a pic of the hillside. That's the deck rail at the very bottom of the picture, where the basin will be. I've decided it will be approximately 7' long x 4' wide x 20" deep. I didn't go any deeper as that would entail cutting into the hillside more, thus creating more of a "wall" on that side. That's a tea olive barely showing on the right, and I want the small 1' tributary to branch off up top somewhere and meander under the right branches, back around and down to basin.

Also, to be clear, you guys are saying that the stream liner obviously goes into the basin, but goes UNDER the basin liner by a couple of feet, correct?

Thanks!
Marc

 

[msr0459]

And just to add a little more info, both streams are approximately 22'. The main one will be 22 x 2', the smaller one likely only 22 x 1' or so. I did my calculations based on the .25 depth I see online a lot. I came up with the total of gallons needed at 332.

 

[poconojoe]

If the water is flowing from the stream to the basin... the stream liner has to go OVER the basin liner. Maybe that's what you meant?

 

[combatwombat]

Also, to be clear, you guys are saying that the stream liner obviously goes into the basin, but goes UNDER the basin liner by a couple of feet, correct?

No! Opposite!

 

[GBBUDD]

You want to build from the bottom up if possible and that liner should get brought up the hill I'll go with a foot or more.
then the stream starts a foot below or more from the top of the basins liner . Laying on top of the basins liner . I myself would seam it just because I can.

. Or possibly just caulk it. The only reason for this is to insure something doesn't move while building around it. Like that never happens.

then if you have a waterfall or a biofalls that ultimately should be the same liner but if it needs to be a third then the stream liner gets placed VERTICALY ABOUT A FOOT HIGHER THAN THE LINER FROM THE BIO FALLS.
the biofalls liner then gets placed overlaping the streams liner .

if my waterfall is say for foot wide then I will try to make a collection area that is also 4 feet wide off to both sides

why would I do such a large area because I am cheap when it comes to water. And that will be a constant drain on the pond. If the wind blows and you have a say three foot drop on the waterfall or even a foot . With the right wind it can blow the water right of of the containment.

now you can use character stones/ large boulders of to each side of the falls and out Infront of the falls a bit making a horse shoe. This too can stop the wind from blowing the water out of containment.

 

[j.w]

@msr0459

 

[msr0459]

If the water is flowing from the stream to the basin... the stream liner has to go OVER the basin liner. Maybe that's what you meant?

No! Opposite!

Lol, that's what I was originally thinking, it makes sense, like shingles. Somehow I misinterpreted some info here.

 

[msr0459]

You want to build from the bottom up if possible and that liner should get brought up the hill I'll go with a foot or more.
then the stream starts a foot below or more from the top of the basins liner . Laying on top of the basins liner . I myself would seam it just because I can.

. Or possibly just caulk it. The only reason for this is to insure something doesn't move while building around it. Like that never happens.

then if you have a waterfall or a biofalls that ultimately should be the same liner but if it needs to be a third then the stream liner gets placed VERTICALY ABOUT A FOOT HIGHER THAN THE LINER FROM THE BIO FALLS.
the biofalls liner then gets placed overlaping the streams liner .

if my waterfall is say for foot wide then I will try to make a collection area that is also 4 feet wide off to both sides

why would I do such a large area because I am cheap when it comes to water. And that will be a constant drain on the pond. If the wind blows and you have a say three foot drop on the waterfall or even a foot . With the right wind it can blow the water right of of the containment.

now you can use character stones/ large boulders of to each side of the falls and out Infront of the falls a bit making a horse shoe. This too can stop the wind from blowing the water out of containment.

Can't really build from bottom up because of logistics. I'm hiring a guy with an excavator and bobcat to help. He's also going to collect some large stones I located out in my woods behind the house, and place them as needed up top, then work our way down placing stones. The basin would be right in the way of him attempting to place some larger rocks up top. Not ideal, but I have to start at the top and come down. My plan is to have everything in place, i.e., spillway and streams/falls dug out as per what I "think" I'll need, liner in place, then have the excavator place the stones.

Not sure what you mean by "collection area"? I hadn't considered the wind blowing the water around, but I do plan on using some larger character stones flanking the falls.

Thanks again,
Marc

 

[msr0459]

then if you have a waterfall or a biofalls that ultimately should be the same liner but if it needs to be a third then the stream liner gets placed VERTICALY ABOUT A FOOT HIGHER THAN THE LINER FROM THE BIO FALLS.

Sorry, I'm confused again as to what you mean by "biofalls"? I plan on having the one main fall after the ONE spillway, then somewhere shortly thereafter branching off from that stream into the smaller stream. Is this the one you referred to as needing to be "vertically about a foot higher than the liner from the bio falls." If so, I should somehow start the second stream liner up from the spillway?

 

[GBBUDD]

splash zone outside the waterfall area = collection
if you have large boulders you want those like a horse shoe falls at the bottom of the shoe boulders coming out on the sides. that way the splash hits the character rocks and falls into the stream.

also each waterfall should drop into a small pond/puddle that way it helps control water in motion.

it also will give you the ability to turn the falls so one your looking at head on while the next is more of a side shot. makes a far more interesting affect. also makes it east to start and terminate a side stream