Plastic Concrete? - 06/05/09
Greetings Bob,
<Dennis>
I greatly appreciate the numerous articles and responses to questions that I have found from you as I have scoured the internet for a variety of information relating to ponds, pools and water features. I have a question regarding the use of plastic cement in fish ponds and waterfalls.
<Okay>
I have already completed excavation of a waterfall that leads to a pond. I’ve made a few of these in the past, and they all have been ‘liner only’ streams and ponds. I’ve decided to have this water feature utilize an EDPM liner, and then a concrete layer on top of the liner (first time for me w/ concrete for me). The liner is all in place, and I have supported chicken wire about 2.5 inches above the EDPM liner using hundreds of 2.5 inch cut lengths of 2” ABS pipe (the 2.5” sections are held in place using zip ties that attach the ABS pipe sections to the wire; single drill hole through the pipe works fine). I’m ready to start with the concrete (I’ll be hand packing J), but have a few questions.
I had planned on using a Portland cement based concrete (3 parts aggregate, 2 parts sand, 1 part cement) for this project, but was in intrigued by a number of references to plastic cement on the internet and in some newer books on water features. I am pretty sure that I want to use plastic cement, but I am unsure as to whether I should have an under-layer of ‘traditional’ concrete (and then a layer of plastic cement), or if I should just stick to a structure that utilizes plastic cement alone.
<Just the plastic cement in place of the Portland>
I plan on an overall thickness of about 3+ inches; is this thickness ok for plastic cement?
<Yes... along with the aggregate (small sized... "pea"... nominal 1/4", and sharp sand, water... oh, and color/oxide>
My understanding is that a standard ‘mortar’ mix for plastic cement has about 4 parts sand to 1 part plastic cement.
<Yes... but I would add some aggregate... likely at least 1, 2 parts to the mix here... won't weaken, will improve the looks>
I was thinking about laying some plastic (thick garbage bags) over the cement as it hardens,
<Mmm... I wouldn't...>
and then placing the larger rocks on top of the plastic to make indentations that will later accommodate the rocks.
<Well... I would try to just mortar all in place as you go along... start from the bottom... and do your best to not make too much of a mess... use large "yellow sponges" and clean water as you work your way up... Not possible, practical to "pre-make" spots for the rock later... nor necessary for seal/leaking's sake due to the use of the EPDM liner>
Once again, I’m kind of thinking that a plastic cement (mortar mix) might be a good way to then fix the rocks in place (in the indentations made earlier). I initially thought I would use some sort of latex or foam sealer to fix the rocks in place, but I’m starting to think that maybe the plastic cement might do well for that also.
<It will... and is the route I would go... Have some labor/help there if this is a big job... to mix the mortar/concrete, help with clean up>
I also wonder if you can make concrete from plastic cement.
<Yes you can and should>
It seems that Quikrete’s plastic cement is just Portland cement with latex additives,
<Mmm, yes... and this co. does have some cheap to better admixes, mixtures... but I encourage you instead to "make your own"... buy the big bags (90#) of plastic cement, and sand, aggregate, colour... and blend, mix yourself just ahead of applying>
so I thought that maybe using pea gravel aggregate would not only be esthetically pleasing, but maybe would give some addend strength to the overall project (I really don’t want to have to redo this later on due to cracking J).
<No worries re in any case>
And if that isn’t enough, I’ve also heard that a mixture of just plastic cement and water (to a paint-like consistency) makes a good sealer for concrete work.
<Can>
Am I getting carried away with the idea of plastic cement?
<Not at all... is much easier to work with, less caustic... "prettier" as well>
Thanks very much, Dennis
<Certainly welcome. Bob Fenner>

Re: Plastic Concrete? 6/5/2009
Bob,
Thanks very much for your response and suggestions; you have really cleared things up for me and I am excited to move forward with the project.
Once again, thanks - Dennis
<Welcome Dennis... this does read as a well-thought out project... Am sure you will enjoy the process and product. BobF>

Pond liner Sagging Under Waterfall Creating Leak  5/29/08
Hi,
My daughter just bought a house that has a pond that had been sitting with fish in it and no filter or anything running since fall. We temporarily housed the fish, cleaned the pond, added pump and biologic filter, added the bacteria treatment. The pond has a waterfall, which she would love to have the water run over. When trying that, the pond leaked very quickly. We realized that the liner has come loose under the waterfall, allowing some of the water to run behind it.
<Very common>
For now, we are just directing the water back into the pond instead of over the waterfall. When trying to slide the liner back up and under the waterfall, we can't quite get it to slide up and under, the gap is so little to maneuver our fingers under it. The entire waterfall is cemented into place, so we cannot lift the bottom rock, which acts as a ledge to lay over the liner. Since just buying the house, she does not have the money to have the waterfall rebuilt to fix this. Do you know of a way to fix this?
<Mmm, yes...>
One friend recommended pushing the liner up as far as we could and then directing the black expanding waterfall foam sealant between the bottom rock and the liner.
<Mmm, not likely to work... but no harm in trying>
In this theory, the foam would expand and sort of "pinch" the liner into place. I don't know if this would work, but without having the money to completely redo the waterfall, I can't think of a better idea. Also, do you know if this black foam is safe for the fish?
<It should be once cured>
Thank you,
Carmel
<The only real for sure fix is to rebuild a new water proof trough over the existing falls area... to affix a sheet of liner over the present construct, build/mortar rock around this, and have the water discharge into the new fall/trough. Bob Fenner>

Building a basin for an outdoor fountain  04/14/2008
Hi,
I've been searching the web looking for information on how to build a basin for a fountain. I would like to build something about 8 ft diameter and> around 24 inches depth. I would be cutting the thing out of a patio slab
<Mmm, I'd build it over...>
and would like it to be slightly recessed below floor level.
<Oh, I see>
I don't have a lot of knowledge about what I'm doing but actually enjoy this
<I'd have a professional outfit cut/core the existing slap if you're going this route>
type of working and have done some pretty good work with other meaty projects from a tiered retaining wall to a large pergola over the last year
<Neat!>
and the fountain is my last project in the yard. I was planning on using cement blocks and setting a footing with plumbing and lights in it and a stand for a basin type of fountain in the middle with angled cement caps for an 8 ft diameter. Could you direct me to resources to find the required directions and> materials. I'm trying to do this on a shoestring so any access to free web related material is a blessing. Regards, Mark.
<Such activity is discussed in passing in a few articles and FAQs files here:
http://wetwebmedia.com/PondSubWebIndex/Pond%20Sub%20Web.htm
in the Construction tray.
Bob Fenner>

Waterfall advice needed  9/20/07
I am building a Koi pond, using flexible liner, that will be about 2000 gallons. I have purchased a Rubbermaid 100 gallon stock tank to use as a biological filter and as the start of my waterfall. Plans I've found on the internet suggest cutting a round hole in the plastic tank and using a 1.5" PVC pipe to deliver water out of the tank and onto the waterfall.
<Too small. Won't accommodate much flow>
However, what I would like to do is cut about a 10" rectangular hole in the tank so that the outflowing water is more widely dispersed and in fact becomes the first "fall" of a 3 tiered falls.
<Okay>
Since I paid good money for this tank, I don't want to just cut into it without first having a plan about how to create this overflow lip. Any help would be appreciated in what material to use or how to design such an opening in the stock tank. Are there wide, narrow flanges I can buy, or do I need to fabricate something from scratch.
<Mmm, these tanks are made out of polyethylene I believe... nothing really adheres to it... can cut another piece of plastic of some sort... rigid, drill and screw it over a cut here... maybe use a heavy-bodied "roofing tar" material to fill in the area in-between>
And since I'm asking, it's not entirely clear to me where and how the liner ends or attaches at the upper end of the falls where it meets up with the stock tank to ensure that things are water proof and no water is being lost in the closed system.
<Ahh! The key question... best that the liner finishes up both under and around the stock tank... such that any water that gets out of it is directed onto the falls (which have the liner under them as well...>
Thank you very much.
Achilles
<My further input re falls here: http://wetwebmedia.com/PondSubWebIndex/h2ofallconstr.htm
and the linked files above. Bob Fenner>

Water sealant for Koi pond waterfall   8/24/07
I have a Koi pond (see www.interall.co.il/pond.html
<Nice pix and great documentation of your project! Glad I wasn't there digging when you hit those rocks!>
for further details) and I would like to use a water sealant on the edging stones as well as the waterfall stones so as to inhibit Ph rise (Ph is at 8.4) as well as GH (16) and KH (10) rise. I have found Thompson's (r) Water Seal (r) Clear Multi-Surface Waterproofer
http://www.thompsonswaterseal.com/products/list.asp?show=home.products.wtrPrf.multi
and was wondering whether over time the sealant would leak into the pond.
Thanks,
Hank
<Mmm... not much of an issue... as the material is quite chemically inert once it is cured... But... don't have much confidence that this application will last... or get you "where you want to go" here... How hard, alkaline is your source water? I might set up a trash can... near the pond... to adjust the water quality over time/changes... and use some live plant material as a mediating influence in the meanwhile... Not (too) hard to slowly drive, modify water chemistry over time here... Bob Fenner>

Pond waterfall, const.... Some large questions, lack of knowledge re...   4/2/07
I am constructing a waterfall in my farm pond which is 3/4 acres. I have had rocks delivered and a track backhoe is going to cut out the earth to create the waterfall. Do you have any suggestions about the placement and lining of the waterfall area and holding overflow pond at the top?
<Many... for one, I would construct at least a Class 2 foundation under the rockwork... better, what I term a "structural trough"... You have read my articles on WWM re?>
I am planning a submersible pump to draw the water up 20 feet.
<... Mmmm, I strongly advise you to thoroughly investigate this selection... Submersibles cost substantially more to operate than emersed... and there is a HUGE range period in each's efficiency... You want to know what you're getting into here... as the cost of operation can be excessive...>
  I was wondering if you could give me a suggestion on the design of the intake part of the water pump. Do I need to put some form of housing around the pump to keep the debris of the pond from clogging the intake?
<Mmm, depends on the nature of the biota here... usually a "wand" (a tee'd off line, with laterals going out, elbowed up, elbowing a few feet up to join back together... with adequate size, number of holes drilled in it (schedule 40 PVC should be fine) is what I'd suggest... but... again, depends on a few factors... like the tolerance of your pump to move solids...>
If a filter is placed, how do you retrieve it from the bottom to clean?
<Mmm, not advised to place a meaningful filter on the intakes of such (centrifugal) pumps... Really... I suggest you study... and likely see if you can get some folks to come out, bid this work, take their advice...>
Thank you for any help.
John Byers
<There are books that touch on such engineering... however none are "complete", practical in my opinion/experience... Read what is on WWM: http://wetwebmedia.com/PondSubWebIndex/Pond%20Sub%20Web.htm
Bob Fenner>

Waterfall Pump Selection   1/3/07
Hello-
<Hi there>
Was wondering how many and how big of pumps OR how do you determine how many and how big of pumps would be needed for a waterfall 30 feet wide by 8 feet tall.
<Mmm, there are "performance curves" for any number of pump and impeller combinations... available through suppliers... from their manufacturers>
The fall will be constructed from larger rocks and will be wider at the base so the water can crash on the rocks.  We are looking for white water and noise, lots of noise.  
<Ah, yes... our old business got to the point of bringing recordings of noise from a few types of pumps... to help the customer gauge how much pump... and cost to operate...>
The top pond will be about 400' x 180' and @4' deep.
<Only four feet deep? May be difficult to maintain...>
  It will also be lined.  
The bottom pond is not lined.
<How will it be rendered waterproof then?>
So I just want to pump water from the bottom to the top and have enough water (2" ???) to make it crash.
<... okay>
Any response would be greatly appreciated.
Thank you
Cameron Marcelle
<Umm, Cameron... I would call on a pump engineering firm near you here... The cost of operation of this device is of paramount importance to the end-user/s in the long/er haul... Will be considerable. Bob Fenner>

Cutting fiberglass 8/18/05
Dear Bob
<Lisa>
I am using a hot tub shell as a pond in my yard.  There will be a waterfall into it.  I want to cut the edge or lip off the existing hot tub.  Can I do this or will it splinter and split?
<Can be cut... either layered or sprayed fiberglass and resin... with a small power tool, gloves, respirator/simple particulate mask, long sleeve tee-shirt, long pants... and taking your time... A "jig-saw" with a fine toothed blade, taping over the area, drawing a line on the tape... (to reduce splintering, and small bits flying about)... take your time... not hard to do. Bob Fenner>

Waterfall 8/18/05
We have a pretty large Koi pond, with a purchased water fall make of fiberglass. we want a larger one and have been thinking of how we could build one about maybe 4 to 5 feet with a couple of drops. we think we can build out of concrete, using chicken wire as a base...
<Can, could>
i have looked all over the internet for ideas.. i don't know if this will work.. what do you think?
Tim and Helen Musgrove
<Please read here: http://www.wetwebmedia.com/PondSubWebIndex/Pond%20Sub%20Web.htm
The articles, FAQs files on waterfalls, fiberglass... Bob Fenner>

Waterfall 8/1/05
Dear Mr. Fenner,
<Hello>
I apologize if this is the incorrect way to correspond, but I saw an email address and just clicked. I live in South Africa, and I have recently finished some major earth moving on my property. While moving earth we uncovered some very large rocks that we merely propped up against a bank, over which storm water reticulated from the surrounding area (smallish natural catchments as well as a bit of storm water run-off from surrounding roads) flows. In summer I have observed the flow to be quite substantial, but no more than can be handled by a 300mm concrete pipe that the municipality uses to reticulate the storm water onto my property.
<As they say here, "Now, that's a pipe!">
My problem is that we simply stacked the rocks up, with no thought as to the structural integrity of the feature, or how the water would all flow into the pond (for recirculation back to the top of the waterfall in times of no rain). The rocks are very large, and are stacked next to a small pond that we dug. Unfortunately there is no way that I can get machinery back on site (and in any event placing massive rocks with a back actor proved almost impossible). Should I scrap the idea of the waterfall, or do you have any ideas.
Best regards,
Kevin Higham
PS, I can send some pics if you thinks this might help.
<Might... but I would definitely do "something" to stabilize this pile of rock... I take it they are sitting on just the original grade, not a whatever class foundation... I would pump as high a compression strength mortar (colored) twixt the mix/spaces of this rock as you can... and if it's not too dear, drill and pin the outermost rock with whatever diameter rebar you can afford, have access to. As the rock itself is not set on something substantial there is still a chance of it all falling... hence, I would not place a seat, structure too near it. Bob Fenner>

Waterfall construction A,B,C's 7/14/05
Robert,
     I am here in San Antonio and my contractor just walked on me with a little of my money.  I am trying to finish this pool myself and ran across your article and need all the help possible constructing my waterfall.  It's not a big area in the gunite, about 6' by 3' deep already cut into the gunite.  HELP!!!  Anything you could say or do or even recommend would be a big help.  Thanks
Milan
<Mmm, well... know that the current material is actually NOT waterproof... you can seal this much the same as your pool (very likely with cement "plaster"... or have the (likely union) folks do this along with the pool... Or, build the falls "over" this space... as detailed here: http://www.wetwebmedia.com/PondSubWebIndex/h2ofallconstr.htm
with a liner... Bob Fenner>

Waterfall construction 6-28-05
Hi, I just have a question. I am in the process of building a waterfall. I have used a ready mix mortar but my husband is not happy with it. It has some cracks. I think it's because we didn't let it fully dry.
<Mmm, there really is no way to avoid these cracks, to make such a construct leak-proof... Have you read my piece: http://www.wetwebmedia.com/PondSubWebIndex/h2ofallconstr.htm>
I read on this site that we should use a cement mix with plastic fibers in it.
<Not by me>
The only thing I could find was a fiber reinforced concrete mix. Will this do?
<Ah, no>
I have looked at Lowe's and Home Depot and when I ask for cement with some plastic in it they have no idea what I'm talking about.
<... is not cement with plastic in it... but a type of cement itself... "plastic cement"... easier to work with, less alkaline...>
If this is not good should I put an expandable foam over the mortar?
Thanks,
Allicia
<Please read the above link, the Related FAQs linked there at top. Bob Fenner>

Re: Waterfall Construction 6-28-05
So you're saying I should use the plastic cement?
<This is better... yes, but...
http://www.wetwebmedia.com/PondSubWebIndex/h2ofallconstr.htm>
<Please read the above link, the Related FAQs linked there at top. Bob Fenner>

Water curtain
We are a landscape company in New Zealand.  The water feature we are constructing is basically a plastered structure that allows a sheet of water 3m across to drop 2.6m. Water will be pumped from a reservoir up into a header tank. This will then over flow creating a sheet of water that drops back down to the reservoir. We are uncertain what volume of water would be required in the header tank and the size requirement for the reservoir and pump.
<A/the rough equivalent "rule of thumb" here is about one gallon of water delivered per linear foot of wall per minute... Bob Fenner>

How to Make the Water Fall
>Our waterfall was completed in October, comprised of a bed of several large stones. The water coming in at a high rate thoroughly washed away most of the clay between these stones. The water created its own rather circuitous route around all of these stones, no longer being an actual waterfall. What material can I use between these stones to bring the surface back for the water to rush over, instead [of] between? 
>>Ah! Easily answered. You MUST go to eponds.com, they have expanding foams SPECIFIC to pond and waterfall applications. To the best of my knowledge/use, they cannot be used to create structure, fill-in only. I've used the black foam for exactly such an application.
>We are in zone 5, so the freezing temperatures are a concern with heaving, which is why I have avoided concrete so far, but at this point any suggestions will be much appreciated. Are there any expanding foams or elastomeric materials that would serve the purpose and withstand the winters here in the snowbelt of Ohio? 
>>See above, but I would consult eponds directly regarding your zone. I'm new to living in snowy areas, at this point have NO experience whatsoever with such other than learning to drive in the stuff.
>The stones are all pretty much above water level and for now, I have a rather ugly solution of a vinyl tarp to direct the water over the stones. Thank you much for your time, J
>>Eponds is the shiznit, my friend. Marina 

Building Waterfalls
Sorry about the caps! I wanted to know how you got started and what made
you decide that building falls
was what you wanted to do with your time?
<Mmm, my pond building likely stemmed from the time I spent as a youth in Japan, and working in the pet-fish interest... in Southern California I worked as a laborer in the late sixties helping a Japanese gardener/pond builder... and in later years found myself helping our companies in small to large projects involving falls in water garden effects. So, serendipity more than anything.>
Did you go to school for training
in any of the knowledge needed to be where you are at?
<No formal schooling, but read quite a few foreign works on water gardening, Koi keeping... and had wonderful experiences observing natural and man-made placements of rock "scapes">
How steady is your
work flow?
<Ahh, I have not "made" falls for a good dozen years. Do get about to consult on others projects, but rarely make artificial or place real rock any more. There is considerable work of this nature in many places however. You should be able to gauge how much interest by looking at the "Yellow Pages" in the town, locality you're interested in locating... under "gardening". Do you see many offers by companies to design, build out water features?>
I saw just two or three photos on your site
but did I miss some?
V/R
Kevin Bowlin
<I have many (thousands) of such pix... their presentation is a matter of time, space, desire. Bob Fenner>

Waterfall sans pump
It is possible to recirculate water within a waterfall and pond without a pump by using high mounted remote sealed reservoirs, can you please send me some info on size of tanks and hoses.
CHEERS
Simon Curnow
<Mmm, I can imagine what you might have in mind here... to move much water though, it would be easier, simpler, cheaper to build/buy a generator, pump et al... Bob Fenner>

Waterfalls and mortar
Bob,
I am building a waterfall for my fish pond and would like to use mortar to set my rocks onto the liner so the water will go over the rocks instead of under them.  I am concerned about the mortar leaching out into the pond.  Is there anything I can do to the mortar to prevent this?  I've tried the black biofalls foam and found it very difficult to work with.
Thanks,
Gail
<Yes. Make sure and use "plastic cement" in your mortar mix... much less alkaline than "plain" Portland cements... Mortars are just cement, sharp sand, water and possibly a coloring agent... and easier on your skin in working with it as well. Bob Fenner>

Waterfalls and mortar
     Thanks for your prompt reply!  Could you clarify what is "plastic cement"?  I was thinking of trying  latex base DRY LOCK Masonry Waterproofer over my etched mortar. What do you think?
Gail
<... nope. I would see here:
http://www.calportland.com/colton/coltprods.htm#PLASTIC%20CEMENT Just ask your supplier for plastic cement... they will know what you're looking for... much lower alkali content. I would NOT rely on a sealer... these wear and chip off over time. Bob Fenner>

Waterfall Sealer
Greetings,
I have an old (15 yr) waterfall constructed of rock and what looks like regular masonry mortar. When built, I do not believe there is any water barrier substrate that was put behind the stone so the waterfall now leaks like a sieve. I have filled mortar gaps with several different products that reduced the leakage, but I am still losing about 20% of my pond water daily to leakage out of the system. Can you recommend a clear, preferably acrylic, stone/mortar sealer that I can paint of the surface to seal it? I have fish in my pond, so it needs to be non-toxic.
Any recommendations?
<Unfortunately all the clear sealers I'm aware of have no "body" or elasticity... My only real suggestion is to use the present fall structure as your "structural trough", lay a waterproof liner over this and mortar a new one over it, making sure the water discharges well-over/into the new underlying liner. It seems you're familiar with the "waterfall construction" piece archived on WetWebMedia.com, perhaps this can grant your further insight. Bob Fenner>
Thanks for your help.
Jon Usher

Building Waterfalls
Hello ...
My name is Ashraf, I am Egyptian but I live in Kuwait
Kuwait is nice and rich country but its very poor when it comes to natural views.
I don't want to waste your time, so I'll get straight to the point.
I am working in Air Conditioning field, I have an idea and I am working hard to design and make it true.
I like to design a mountain with water falls, and because I have good idea about refrigeration, so I'll make simple refrigeration circuit to have true snow at the top of the mountain. and the water starts to flow after the top, so the viewer will imagine that the ice is melting and flow.
I need your help in designing waterfalls, I have no problem with snow part.
could u help? 
thanks for reading
Ashraf
<What little I know re waterfall construction is posted on our site, mainly here: http://www.wetwebmedia.com/PondSubWebIndex/h2ofallconstr.htm
Do you have specific questions, concerns?
Bob Fenner>

Waterfall problem
Help!
The design:                    A little over a year ago we expanded our patio and added a retaining wall using Crab Orchard fieldstone (and other stone) with an integrated waterfall.  The lower concrete pool contains a pump which pumps water to the upper concrete pool which when full, over flows down the face of the stone and collects in the lower pool.  The pools are no more than 4 feet long by 2 feet wide by 2+feet deep.
The problem:               We have noticed a loss of water volume during operation but don’t notice water leaking from the horizontal (patio) or vertical (either side of the waterfall) surfaces.  Neither pool losses leaks.
The suspicion:             Other than minimal amounts lost via evaporation and absorption, water may be leaking through “imperceptible” mortar joints between the stone.
<Very common>
  I cannot conceive of another reason for nearly the entire loss (approximately 2 feet/day) of water.
The solution:                If my suspicion is correct, then an application of a clear, waterproofing material over the surface of the stone may prevent rapid water loss.  If so, what product is recommended?
<Unfortunately as far as I know there are no such clear sealants. I recommend a cementations coating (like Thoroseal tm) that can be dyed to somewhat match the rockwork... note the height of water in your falls during operation and apply this material up to that point. If there is a suspicion that the rockwork is still moving (it was built on a solid foundation I trust), you may be better off with a coating with elastomeric properties (so it can/will stretch rather than crack)>
If suspicion and solution are incorrect, please provide additional advice!
Thanks
Bill
Florida
<Bob Fenner>

Waterfalls
Mr. Fenner,
I work at a newly constructed golf course and we recently started to construct some waterfalls in our creek beds. Our creek also will have 425gpm pumped through them. One creek is approx.20ft
long and we have five feet of fall from one end to the other, is that enough?
<Enough? Yes, for appearance's sake... if this is close to actual gallons per minute (versus calculated)... and you might do well to secure a weir of sorts (large flat rocks mortared somewhat together, in place on a substantial edge on the falls lip...) to make the flow of water more spread, giving the appearance of greater rate and saving it from erosion>
We were also not planning on using any liners or concrete bases, will that create a problem?
<Likely yes... do read over the sections on the WWM site on falls and basin design and construction...  Home Page ... Much of the face of this planet was formed (as you know) through the forces of water movement... I would plan on engineering at least the edge and face of the waterfalls of liner, con-shotcrete, and reinforcing mesh and rebar... NOW, and not try to rebuild it later after so much is washed down. Bob Fenner>
 Please let me know if you have any tips or any ideas.
 Thanks  Jason Kruse