Automatic Siphon System Idea

Well after struggling for hours trying to get this drawing loaded my wife did it on her computer for me in less than 10 minutes. Maybe now someone can critique this idea for an automatic siphon system idea in northern climates. As I stated in a previous post, the entire system would be buried to the depth of the frost line in your location. My handwriting is terrible I know. Good or bad, all comments are greatly appreciated!
Heppy

I guess it would help if I provided a little explanation. If you look at a normal automatic bottom draw siphon system the vent is above ground allowing the bottom draw to act as a normal overflow pipe until the water level covers the vent hole. Once this happens your bottom draw goes into siphon mode until the water level drops below the vent opening breaking the siphon mode. It then returns to normal overflow. Northern climates have to contend with freezing conditions in winter and Southern climates have to make sure their vent doesn’t get blocked. If the vent gets either frozen or blocked, there is a risk of entirely siphoning your pond. The only difference with the idea that I have would be that the entire system would be completely buried below the frost line in your location. This idea would eliminate both possibilities if it will work. The downward open end of the vent that will reach the water in a siphon control would extend inside a larger piece of pipe that is higher than the apex of the main siphon pipe. An adapter (example 2” pipe to 4” pipe adapter) is also higher than the apex of the siphon pipe would allow you to have the smaller pipe inside a larger pipe with hole(s) drilled in the smaller pipe up to the point it reaches the apex level of the siphon pipe. The solid larger pipe would extend underneath the face of the dam before coming out into the water side face of the dam (trash rack on the end of the larger pipe???) that would then be covered with rock to allow water not debris to rise and fall in the larger pipe as the water level rises and falls. The hole(s) in the smaller pipe inside the larger solid pipe would control when the water siphons and stops. I was thinking this might be a possible solution for those in northern and southern climates. Comments?
Thanks,
Heppy

http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=482496#Post482496
This is the post by DC70 that got me thinking you could possibly use just one siphon pipe.
Heppy

Hi Heppy. That’s an interesting idea and it definitely makes me think....

I may not be completely wrapping my head around it, but is the larger pipe (4” in your example) that you have drawn around the vent - is that open to the atmosphere somewhere? Seems like it would need to be open to let the water inside raise and lower with the pond. You may have already accounted for this, but if you were to add a small pipe from your 4” pipe to the surface to let air in and out, it just may work.

Hogfan, an automatic start/stop siphon has a small pipe for a "siphon break'" and is set at a few inches above "full pool" water level.

Water will always raise or lower in the main pipe, because the atmosphere forces the water up the inlet (water always seeks it's own level and is the water level is the same inside the pipe as it is outside it)

When the vent pipe is under water in a rain event, AND the pool level reaches the bottom of the highest siphon pipe point, the siphon automatically starts.....when the pool lowers, and the vent sucks air, the siphon stops and becomes a "normal" drain again.

Edit:

A siphon inlet and vent pipe need good trash guards to eliminate the possibility of a clog...if an inlet plugs from a turtle or fish, the dam could get breached...if a vent gets plugged, the pond lowers to the inlet level of the siphon. A 45* angle pipe on the outlet that pools and "seals" to stop air entering from the outlet is a must also, or the siphon will hammer from stopping and starting over and over

Heppy, I don't understand why you have so much depth for your vent tube.....

Rainmain,
I was thinking of having the multiple vent holes in the smaller pipe if there was some type of build up that might happen because it is buried that I hadn’t taken into consideration when starting and stopping the siphon. If I am overthinking this a smaller pipe cut a few inches above normal pool buried might be the better option. In the drawing it shows covering the larger pipe with rock and some type of trash guard. What would you suggest as an ideal buried setup for an Automatic siphon system?
Thanks!
Heppy

Heppy, after I first saw DC70's system I had the same thoughts regarding a completely closed system. I also have the same thoughts as Hogfan, regarding whether or not the chamber needs to be opened to the atmosphere to allow the displacement of air with water. Perhaps a sufficient volume of air in a completely close system would overcome vapor lock, and allow it to work, I dunno.

I suppose some experimentation could be done on a smaller scale using small piping or tubing. If a full size system were built and it failed, at least you could correct it by way of adding a vent tube as Hogfan suggested.

Also, perhaps I'm missing something, but I don't understand your idea of drilling the holes in the smaller vent pipe. It seems to me that the highest hole in the vent pipe is the only one of importance, therefore that is where the end of the pipe should be, as with a normal automatic siphon system.

Edit: Doh! I just saw your above post, where you explained that the perforated vent pipe acts as a trash guard. That's a good idea!

Heppy, the vent being buried may be a bit of overkill, but as long as the "larger" pipe is vented to atmosphere, you could certainly use a pipe that goes under the water to allow the vent supply tube to let water rise and fall.

For strainers, I keep it simple...for the inlet of the siphon, I use a 10' long TEE (5' on each half) with caps on the ends. I drill about 150 1/2"-1" holes in the TEE on each half...this reduces overall suction at any given point, and prevents fish, trash from clogging anything. For the vent..very course rock may work, but will probably silt in over time....a TEE for the water level tube similar to the siphon inlet may be better (no pressures for anything to clog)

Note...with no covers on the inlets in DC70's design, turtles or large fish could easily plug the pipes, plus a stick could get sucked in and get trapped in an elbow...once leaf litter enters the pipe, it will plug up like concrete and become a real bear to try clearing

Rainman,
I like the way you use the capped 5’ of perforated pipe on each side of the TEE as your trash guard on your siphon pipe. I also think that would be ideal on the larger vent supply pipe. Is it correct to assume using the modifications you have suggested will work in any climate buried below the frost line? If this is correct I will post another drawing that others may refer to in the future.
Thanks!
Heppy

It will absolutely work, as the piping will never freeze. I'd also suggest no larger than 3/16" holes drilled into the upper 4" of vent pipe itself with larger (1/2"-1") holes lower so there will be far less venturi (whirlpool) action that will lower the vent supply line and suck air, making the siphon hammer stopping and starting. (you'll be amazed at how much destructive force there is when the siphon stops and starts). Also, make the vent pipe rise about a foot higher than shown in DC70's design, and raise the vent supply pipe as well (also to prevent supply pipe level drop/air entering)

Rainman,
I just emailed a drawing to you to for confirmation.
Thanks!
Heppy

Hogfan and gully washer
You are correct! There needs to be a vent to the surface from the 4 inch pipe. I just got off the phone with Rex (Rainman). He will be in touch with me later and a diagram will be posted soon.
Heppy

Roger that - I think that will work. Rereading DC70’s thread, I initially missed this statement: “I ran a 4 inch piece of pipe to the surface with a grate flush with the ground for the air to enter.” Appears that he used this 4” line to equalize the underground chamber pipe to let the water inside raise and lower. Sounds like you are on the right track. Whatever you do, don’t let that surface pipe clog, it could drain the pond before it breaks siphon.

Good luck!

I am sorta putting the cart before the horse but what does anyone think of this for a surface vent cover?
https://www.amazon.com/Canplas-133070GN-...v_1535323476419
Thanks
Heppy
Edit: This was posted before I understood what Rex was telling me. I wouldn’t use this.

Automatic Siphon System

Edit: As you will read below the TEE for the vent supply tube is unnecessary.

Tips by Rex earlier today.
Tip #1 Use the rubber stainless steel banded couplers at each joint on the Siphon pipe. The reason for this is to allow some flexibility in the Siphon pipe when it breaks siphon. If you only have glued joints and the joint broke underground you might have to dig up the entire pipe trying to find the leak. Let’s call it insurance. An example Rex told me about that most of you will be able to relate to is when there is air in your water pipes at home. When you hear and feel the hammer of air breaking through your pipes and faucets this is only 1/2” pipe. Now imagine that with a 6”+ siphon pipe. He also recommended painting rubber on each screw on the stainless steel bands because the screw is made of zinc and will quickly rust out.

Tip #2 Put a varmit guard on the outlet pipe on the backside of the dam. It should be spaced approximately 2” apart. If you want you can use rebar. The reasoning behind this is to keep raccoon size critters from crawling inside getting stuck and dying. I’m no raccoon lover but the major problem is if they die they swell up and completely block your Siphon pipe. In turn water could potentially run over the top and wash away your dam.

If you feel this information has been helpful pass it along. This system can be used anywhere as long as it is buried below the frost line wherever you may be located.

Thanks for the help Rex(Rainman) and like you said today as Bruce Condello once told you that “if you know more than 99% of the people around you, then you are an expert.” Rex if anything here is incorrect feel free to let me know.

As I stated before if you cannot read my handwriting I understand, sometimes I can’t read it either. If you need help just ask. The keyboard is much clearer!
God Bless,
Heppy

Sounds like a good plan. Although I do think it would work just fine, I would be a little anxious about the vent going through the wall of the vent chamber pipe with silicone. They make grommets that will do that. Not sure which would last longer underground, silicone or a rubber grommet. If things shift during dam settlement, I think I would rather have a rubber grommet than the silicone. Actually, after I think more about it, I might even bring the vent tube up to the surface and go into the vent chamber above ground...just so I could easily maintain it and there would be no soil to migrate into the chamber above ground. The vent tube won’t have water in it most of the time (except during siphoning) and I don’t see that it would freeze. Just a thought. Definitely not required.

I think that vent cap you posted would work, but I think I would just cap the pipe with a standard PVC cap, and drill holes in the cap and pipe. Leaving the cap unglued so you could remove if needed. I would also be tempted to extend it above the ground a foot or two. I would think that would help keep debris (grass clippings, roots, etc) from entering the chamber. That may help the system last longer. Whatever you do, put a tee post or two around anything above ground so you don’t mow over it!

Also, I’m assuming your vent chamber perforated tees are extending into you reservoir area, correct? Hard to tell from the drawing.

Good luck!

Hogfan,
I’m guessing the rubber grommets or silicone would work just fine. The amount of dirt or debris that enters the vent pipe should be negligible. In my location the frost line is at 18”. In January of this year the temperature never got above freezing for 10 straight days. That rarely happens around here for an extended period of time. However, my objective is to have this system work wherever someone is located. I personally would like to be able to mow over the barely visible vent without concern of hitting the pipes but you are right any pipe above ground should be anchored with a post. Rex said the same thing as you about using a removable drilled cap in order to access the vent pipe inside the 4” vent supply pipe and I might just do that. You are correct the 4” vent supply is at approximately a 45 degree angle extending underground into the water resting on the face of the dam. The depth of the vent supply would need to come out into the pond onto the face of the dam below ice depth depending on where someone was located.
Thanks!
Heppy

Edit: No TEE needed on vent supply pipe.

Hogfan, I suggested heppy make the vent supply line (for water to raise and lower in) to be always angled downward into the pond pool....it will not matter if soil or grass enters the supply pipe....the crud will migrate into the pond...the hole into the supply pipe does not even need any seal at all. If water rose, it is on the pond side of the dam core, so no harm getting things wet, and again, any soil entering would be a minor, meaningless amount. there is no danger of erosion...Last, if your dam "settles" much, if at all, it was never compacted and constructed properly to begin with.

I also suggested installing an access basin around the vent tube crossover and vent supply pipe...and adding valve in the vent tube, along with another TEE on the vent tube between the siphon and valve, so the siphon can be manually started in case you need to do a draw-down or draining of the pond

The vent supply pipe does not need the TEE, only the siphon inlet. Capping the supply pipe, and drilling a couple 1" holes at the lowest point will keep it clear, and then several 1/2" holes elsewhere will allow it to easily stay at pool level.

I think that will work as you described it. Pretty neat idea. Thanks for sharing.

You are right about settlement and proper compaction within the dam, so that hopefully won’t be an issue if done correctly. The textbooks say that settlement usually occurs in the foundation once the weight of the dam is in place.

Thanks for the clarification Rex! Now I understand what you were telling me about the basin and valve. I was looking at an old thread by lassig from 2012 and saw where it said to drill a 1/4” weep hole at the lowest point of the 45 degree elbow on the outlet pipe at the toe of the dam to prevent standing water from freezing in the winter causing an ice plug. Is this your recommendation?
Many Thanks!
Heppy

Hogfan,
Here is a link to the “grommet” if that concerns you. This is for a 2” pipe.

https://www.aussieglobe.com/2-Uniseal-U2...ASABEgKG8vD_BwE

Heppy

A weep hole should work fine, or if wanted, you could make a bend below the frost line yet still close to the outlet that would prevent air entering all the way to the apex

Thanks Rex! I’ve been thinking about making the vent supply pipe larger (6”+) so it would serve as the access basin containing the elbow and downward vent pipe (below frost line) with a grate on the surface of the dam. I also thought I would put the TEE on the vent pipe at one foot above the siphon pipe (for the vent crosspipe) and extend the vertical part on the TEE to the top of the dam (surface). This part would be capped at the surface of the dam. I was wondering if I needed a check valve above the TEE on the vertical pipe between the TEE and the surface cap in order for the automatic and manual siphon to start. In other words, if the top of my main siphon pipe is 24” or more below ground will the amount of air in the vertical portion of vent pipe need a check valve to overcome the amount of air above the TEE to the top of the dam surface for automatic or manual Siphon to start? What do you think?
Heppy

I haven't been on here for many months. Anyways I see some concerns about my setup the OP referred to.

When I first set up what I referred to as a pit (where the vent meets the water level inside the dam), I had an 18 inch dia. x 36 inch long piece of plastic culvert pipe with an 18 inch grate flush with the dam. When it went into siphon, it was really loud. So I cut the pipe off 12 inches below ground level and capped it while running a 4 inch pipe over 3 feet with an elbow then up to the surface with a vent cap flush with the ground. Now you can't hear it unless you are on the dam. The 4 inch pipe acts as a muffler.

In my picture of my 2 intake pipes, I took the picture before I glued on the caps. I drilled enough holes in the pipes to equal over 2x the flow capacity of the pipes.

With out the vent to the surface, the system would air lock. Which I know someone already mentioned that.

You could make this system with one pipe instead of two. When I designed my system, I figured that I needed around 50 square inches of pipe for my calculated rainfall per acres of watershed. 8 inch pipe = 50.24 square inches and 6 inch = 28.26 square inches. The cost of 6 inch pipe was half of the 8 inch. Two 6 inch pipes gives me 56.52 square inches of pipe. So I decided to go with two 6 inch pipes.

DC70,
Thanks for providing additional real life experience with your system! Could you please clarify what you did when you said “So I cut the pipe off 12 inches below ground level and capped it while running a 4 inch pipe over 3 feet with an elbow then up to the surface with a vent cap flush with the ground.” I understand that you cut the 18” pit 12” below ground and capped it, but I’m not clear on the 4” inch pipe over 3 feet with an elbow. Where is the 4” inch pipe over 3 feet connected? Is it on the vent supply pipe (sock pipe), 18” pit or vent pipe?

Thanks,
Heppy

Sorry it took me so long to reply, my internet service has been down. With my first design, I think the 18" pit actually amplified the noise. I had originally thought I would have to run the 4" pipe out into the woods about 150' away to counter the noise. I only had a shovel so I quit at 3 feet and it worked. I made a drawing that isn't exactly to scale of what I did, but maybe is representative of my design. It has been working for 8 years now.

DC70,
Now I see what you were saying! Thank you for the drawing! As they say a picture is worth a thousand words. You wanted to reduce the amount of noise and thought you were going to need to move to the far end of the dam. However, after moving the 4” vent pipe a little over 3’ the noise was dampened (muffled) enough by the smaller 4” pipe. Btw your drawing is much neater than mine.
Thanks!
Heppy
How do you manually prime the siphon if you wanted to do a drawdown?

I have a 6 inch drain with a ball valve that I can use to draw it down. I also have a 4 inch valve for my irrigation.

DC70,
WOW! That is a fantastic idea! Are these pipes separate from your dual 6” siphon? I’m assuming that the valves in the picture above are located at the backside of your dam?
Thanks!
Heppy
Edit: I looked at your original post and can see the separate pipes in your pictures. The irrigation pipe looks to be the one at a 90 degree angle sticking straight up.

It is not recommended to have a pipe through the base of the dam. I had to have a construction drain as it took me 14 months to build my dam. Here is a picture showing the 6" construction drain as I was about half way up with the dam. Here is a link to the story of my pond project: http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=141770&page=1

DC70,
4 years with a skid steer, that is an amazing accomplishment! Incredible! That is some first class work! I understand the concern in having a pipe through the dam. I have made previous comments in this thread about systems that could possibly work for anyone no matter their location. I know that your design does work and has been doing so for quite a while. Let’s say that you had a large dozer and it could be completed in under a month. What if anything, would you have done differently? I like Rainman’s idea of being able to manually start the siphon and having access to the vent pipe and a valve through the larger vent supply pipe that reaches the surface of the top of the dam with a grate. I really love what you have done with the irrigation pipe. You got me thinking is there a way to run the irrigation pipe without piping through the dam?
Thanks,
Heppy

If I could have had somebody build the dam in under a month, I would have skipped the construction drain. I would have either included some valves on my siphon drain with access to the pit or put in an additional pipe for the irrigation. Maybe a 4 inch pipe buried through the dam at water level and down to a valve behind the dam similar to the siphon drain but without the vent. It would have required a pump to get the line full of water and then worked as if the pipe was straight through the base of the dam. Could be used to draw the pond down and or to water my grapes and berries. For irrigation I would have the inlet about 6 foot deep as mine now draws from 17 foot deep and smells like rotten eggs.

Thanks for the detailed information DC70! This has been a great help in trying to find a buried bottom spillway siphon system that anyone can use as a guide. Can anyone answer the question I raised previously in a post? “ I was wondering if I needed a check valve above the TEE on the vertical pipe between the TEE and the surface cap in order for the automatic and manual siphon to start?”
Thanks!
Heppy

No, you don't. The vertical pipe (I assume you mean the vent supply pipe) should always be at atmospheric pressure to rise and lower as the pond does. Once you close a valve on the vent pipe itself, the siphon will drain until you reopen the valve, or there is no more water...

Rex,
I am referring to the the vent pipe not the vent supply pipe. The part of the vent pipe extending to the surface of the dam straight above the crossbar TEE and capped. It would also be directly above the TEE on the siphon pipe. This would be for the manual starting of the siphon. Check valve or not? What do you think?
Thanks,
Heppy

Attached is a diagram of what I was describing about the placement of the check valve in red. I was also wondering if I could place a ball valve that could be accessed on the vent pipe inside the vent supply pipe in the diagram? I'm not sure whether the ball valve has to be on the crossbar of the vent pipe? All comments appreciated!
Thanks!
Heppy

Anyone? I realize most are very busy right now?
Thanks!
Heppy

I don't believe a check valve is necessary. It would probably hinder the filling process, and could potentially fail if a small piece of trash becomes embedded in the seat. It's just as easy and less expensive to simply close off the vent tube after filling it with water. And yes, placing the ball valve on the vertical drop of the vent tube will work just as well as placing it on the horizontal crossover.

gully washer,
Thanks for the response! That is great to know that the ball valve can be accessed through the grate on the vent supply pipe. Just so I understand correctly, the check valve will not be necessary. The reason I ask this question is because I’m unsure if the amount of air in the vent pipe (valve open) and capped surface of the dam will interfere with starting in automatic siphon mode? Will the siphon overcome the air in the system?
Thanks!
Heppy

Other than the extra length of pipe between the tee and the cap, the configuration of the vent in your design is really no different than that of a typical siphon system, so I don't see why your system would need a check valve. If the air trapped in the extra length of pipe between the tee and the cap on your system's vent were to cause an issue (and I don't think it would) you could simply install an automatic air bleeder/vent on the top end of the vent pipe, in place of the cap

You've probably seen this drawing, but here it is just in case you haven't: The drawing of typical siphon system in this link doesn't have a check valve, or air bleeder
Here's some examples of automatic air bleeds:
air bleed
Automatic air bleed

Auto matic air bleed 2

gully washer,
Thanks for posting the links. I have seen the drawing and the main difference in this system is that I wanted there to be a design that anyone could use no matter where they were located. I want this system to work from Florida to Alaska. The drawing you linked has a potential problem with trash (debris or bees nest) blocking the vent and being broken when mowing especially in southern climates. In northern climates you potentially have those same issues along with an ice block in the vent pipe. If the vent were blocked in either circumstance the pond could completely siphon. You are correct the concern I have being the extra length of pipe between the tee and the cap (I will call this part the riser) in starting the automatic siphon. Frost lines vary throughout our country. In areas there is no frost line and in others it may be as deep as 6 feet or more. This is why I initially asked about a check valve. If there were an issue with the riser (which you don’t think there will be), can an air bleed be installed underground on the riser and not have a problem with manually starting the siphon? I’m just trying to find a solution for everyone who wants to use a bottom withdrawal siphon system. I figured with all the knowledge on the Pond Boss Forum we can find an answer.
Thanks!
Heppy

Rainman,
I’m really looking forward to your response to the comments after your previous post.
Thanks!
Heppy