Waterfall - rock is absorbing water

[javinv]

Hello,

I'm trying to rehabilitate an old pond that was installed at my parent's summer house in the mid 90's. As I recall, the waterfall worked and there was no need to refill the pond frequently.

The waterfall consist on a pump that takes the water from the pond into a pipe that goes to the upper part of a rock wall that is on one of the edges. This is a sand rock and has a height of almost 3 meters. I have checked that there's no leak on any part of the pipe.

The water should flow back into the pond making a beautiful waterfall, but somewhere, water disappears. I have tried to fill the rock gaps with a special water resistant concrete and have checked the union between the liner and the rock ( I know in the last photos there's a gap on the concrete, but it seems that is not the problem).

I even installed a garden hose into one of the pipe's outputs on the top to check at what height water gets absorbed and I think it is not at the liner's union with the rock.

This last week I have tried to cover the rock with a big plastic sheet, to check if letting the water just touch the rock at the lower part would make any significant decrease in water level but it looks that it keeps the same level.

So I would say that the rock is absorbing the water... I tried with an Amazon product to waterproof rocks but made no difference...so I don't know how to solve this and I would greatly appreciate any suggestion or advice.

I attach some photos.

Thank you,

Javier

 

[Lisak1]

How pretty!

Did you say there was liner under the waterfall? Perhaps it has a leak. If the rock is in fact "absorbing" water, it could only hold so much, so I really doubt that's the answer.

But rather than trying to seal the rock or use concrete, I'd suggest some waterfall foam. It's used to fill those gaps and cracks and keep the water in front of the rocks instead of flowing behind.

 

[GBBUDD]

Making falls between rock outcrops is by far the most difficult of builds. I don't know where you are but freeze thaws move expand crack and lift concrete all of which is not in the cards for concrete. Even just having the area in the shade untill mid morning then the sun hitting it can throw thermal shock at the concrete heating it up too fast and in time can be the problem .

My second note is your fountains they are way to aggressive I can see water plush right up to the edge of the pond and shooting that high up your going to get a boat load of evaporation and blowing /leaking. Over the course of 24 hours you would be very surprised how little water in a flow is needed to add up. If you don't have a good two feet from the edges of the pond your going to have a lot of water loss.

I've been a builder all my life and have built a lot of crazy things for people at your stage of the game as far as the waterfall is concerned . I would look at fibreglass coatings. Then possibly a gunnite but either way it's a chore to make things like that into a water tight masterpiece.

I'd shut down those fountains and take reading where your water is at the same point Daly for a week then turn your fountains on a record daily again who knows maybe your lucky and its just the fountains causing the leaks.

 

[Mmathis]

Hello and welcome!

I was going to make the same observations as @GBBUDD.

 

[addy1]

Welcome that is a neat pond and waterfall.

Do like said above fill the pond, also turn off the fountains and see if it holds water.

 

[Lisak1]

your going to get a boat load of evaporation and blowing /leaking

Good call - I skipped right over that photo.

 

[j.w]

and welcome @javinv try all of the above and see how it goes.

 

[javinv]

Hello all and thank you for your replies and welcome messages!!

I will try to answer all of your questions and suggestions:

- There's no liner under the rock (the big rock wall I mean); the liner is down on the pond.
- I have tried all of your suggestions already regarding checking if water level goes down if the fountains are on, or if they are off for a week (I have been trying to fix this since last summer!):

1. No fountains and no waterfall : the level keeps the same all week.
2. Fountains ON but no waterfall: the level keeps almost the same all week; I can't assure that there's not a slight decrease but it is very small, if there's one.
3. Fountains OFF and waterfall ON: water level decreases almost 5 cm (2") per day. It could probably empty the pond in a week.
4. Waterfall ON, connected to a hose to check the height at which water starts "disappearing". If the hose is over the joint of concrete, between the blackboards and the rock wall: no noticeable decrease or very slight. If the hose is over the first segment of the rock, which has a light brown color (like sand), water decrease starts to be noticeable after some hours.

Yes, I agree the fountains are too aggressive; I will adjust their height if I'm able to get a stable water level someday.

- To cover the gaps with foam: Which one? should I remove the concrete that I already applied and start over again?
- In the original setup of the pond, concrete was used only to hold the blackboard piece... since I learnt how to prepare it, I started applying it everywhere, but I agree this is not the way.
- About fibreglass coatings and then possibly a gunnite: Is fiberglass something I can do by myself with an Amazon product and a brush? are fibreglass coatings and gunnite part of the same process or is one or the other? which one? should I contact a pool expert to apply them? Isn't any other process I could try by myself before playing the professional card?

Thank you all and have a nice day!!

 

[Mmathis]

I may be wrong, but if there is no liner at all under the rocks/fall area, then the water is likely being diverted away from the pond. Water will always take the path of least resistance, and the only way for it to leave the pond and then flow back into the pond (without any loss) is if the system is closed (IOW, all water contained by a liner). While it might look “solid”, rocks are always going to have micro fractures and diversions.

 

[reefsr]

I may be wrong, but if there is no liner at all under the rocks/fall area, then the water is likely being diverted away from the pond. Water will always take the path of least resistance, and the only way for it to leave the pond and then flow back into the pond (without any loss) is if the system is closed (IOW, all water contained by a liner). While it might look “solid”, rocks are always going to have micro fractures and diversions.

Agreed. Waterfalls should have liners.

 

[javinv]

But how could I install a liner over the rock wall? and how could I stick rocks onto it so it is not visible? the waterfall has an 80 degrees inclination I think.

 

[Mmathis]

But how could I install a liner over the rock wall? and how could I stick rocks onto it so it is not visible? the waterfall has an 80 degrees inclination I think.

Very good question. You might want to consider a different “point of view.” Maybe you can reorient the focal point. Maybe, use the rocks as a design feature (trailing plants?), but build a smaller waterfall to the side. Construct it so that it looks seamless with the rock wall. That way you could still incorporate the new waterfall into one contained in a liner, but it would look like a part of the rock wall. Or, I guess you could blast our a hunk of the wall to make something like a grotto. Make the “hole” large enough that after you run the tubing and set the liner, you would be able, then, to adhere rocks to hide the liner. IDK, just a few random thoughts.....

 

[poconojoe]

As indicated, a waterfall without a liner will leak.

Maybe you could get away with having the water deposited lower on the waterfall. Not having it spill all the way from the top. Maybe have your pipe or hose only a foot or two higher than the pond level. If that works, without loss of water, then make it permanent. You can add plants to the upper (unused) part to hide it.

There's also a product called rock on a roll. It's liner material with a rock pattern on it. You could lay that right on top of the whole waterfall. I have never used it and don't know how realistic it would look, but I think it would fit your situation perfectly.

 

[mrsclem]

Great idea @poconojoe ! The rock on a roll could be glued directly onto the rock face. here is a link to some of their photos.

Rock-on-a-Roll: Photos

Rock-on-a-Roll makes hiding pond liner easy. It is lightweight and flexible and has the look and texture of natural stone. It conforms to any shape, allowing you to hide pond liner, skimmers, filters and hoses without piling up lots of boulders. Rock-on-a-Roll is fish and pond plant safe, and...

www.rock-on-a-roll.com

 

[javinv]

Very good question. You might want to consider a different “point of view.” Maybe you can reorient the focal point. Maybe, use the rocks as a design feature (trailing plants?), but build a smaller waterfall to the side. Construct it so that it looks seamless with the rock wall. That way you could still incorporate the new waterfall into one contained in a liner, but it would look like a part of the rock wall. Or, I guess you could blast our a hunk of the wall to make something like a grotto. Make the “hole” large enough that after you run the tubing and set the liner, you would be able, then, to adhere rocks to hide the liner. IDK, just a few random thoughts.....

Something like this?