Pond Boss Magazine
http://www.pondboss.com/images/userfiles/image/20130301193901_6_150by50orangewhyshouldsubscribejpeg.jpg
Advertisment
Newest Members
Mjfrey, emactxag, thoki, VitalinA23, Farmpond5343
15686 Registered Users
Forum Stats
15686 Members
36 Forums
36099 Topics
491342 Posts

Max Online: 1210 @ 08/23/18 11:01 PM
Top Posters
esshup 24029
Cecil Baird1 20043
ewest 19590
Dave Davidson1 13600
Bill Cody 12520
Who's Online
5 registered (Smoke68, bcraley, bigpullerman, Zep, wbuffetjr), 153 Guests and 213 Spiders online.
Key: Admin, Global Mod, Mod
Topic Options
#388097 - 09/23/14 06:36 PM Where to put the overflow pipes and how large
Flame Offline


Registered: 09/12/14
Posts: 1067
Loc: Deep East Texas
Hopefuly breaking ground on 2 acre pond in about a week. Please someone simplify where and how deep and how large to install my pvc pipe? I have tried to read everything and look at photos posted but get confused easily. How far from the top of the dam should my emergency spillway be? How large of pipe? How far from the top of the dam should my regular drain pipe be? How large of pipe and should I install more than one in various locations? I would love to have a siphon style but I don't think my builder will know how to design it. Where exactly do I install a "drain valve" if I want to manually lower my water level or drain the pond for some reason? Please understand I need simple answers for my simple mind!! Thanks
_________________________
Dear Alcohol, We had a deal where you would make me funnier, smarter, and a better dancer... I saw the video... We need to talk.

Top
#388128 - 09/24/14 12:31 AM Re: Where to put the overflow pipes and how large [Re: Flame]
esshup Offline
Moderator
Ambassador
Field Correspondent

Lunker

Registered: 01/26/09
Posts: 24029
Loc: Grovertown, Indiana
Unfortunately there is no simple answer for your question. Go to your counties NRCS office and they will give you a detailed sketch with all those questions answered. The reason that I say there is no simple answer is because the answers all depend on the amount of acres of watershed that is feeding your pond, the type of soil that is in that watershed, the type of vegetation that is on that watershed, your annual rainfall, 50 year and 100 year flood events, etc., etc.

Then you get to decide on the type of overflow pipe to use. Mike Otto has a great article in this months Pond Boss Magazine on the different types of overflow pipes. Perfect timing!!
_________________________
www.hoosierpondpros.com


http://www.pondboss.com/subscribe.asp?c=4
3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).

Top
#388142 - 09/24/14 09:08 AM Re: Where to put the overflow pipes and how large [Re: Flame]
Flame Offline


Registered: 09/12/14
Posts: 1067
Loc: Deep East Texas
Thank you for your response. I know I would like a bottom style drain, I have the mag. issue with Mikes article. It helped. Just trying to fine tune some decisions.with a siphon system should you still have an emergency overflow? I will plan to use pvc. Thanks
_________________________
Dear Alcohol, We had a deal where you would make me funnier, smarter, and a better dancer... I saw the video... We need to talk.

Top
#388147 - 09/24/14 09:54 AM Re: Where to put the overflow pipes and how large [Re: Flame]
esshup Offline
Moderator
Ambassador
Field Correspondent

Lunker

Registered: 01/26/09
Posts: 24029
Loc: Grovertown, Indiana
Definately always have an emergency overflow.
_________________________
www.hoosierpondpros.com


http://www.pondboss.com/subscribe.asp?c=4
3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).

Top
#388162 - 09/24/14 12:13 PM Re: Where to put the overflow pipes and how large [Re: esshup]
jludwig Offline


Registered: 05/14/11
Posts: 1456
Loc: Central Kansas
Originally Posted By: esshup
Definately always have an emergency overflow.


If it saves your dam once, it has done job it designed to do.

Top
#388170 - 09/24/14 01:20 PM Re: Where to put the overflow pipes and how large [Re: Flame]
snrub Offline


Registered: 10/05/13
Posts: 5261
Loc: SE Kansas
Emergency overflow? With you living in an area that sees the remnants of Gulf hurricanes? OH YEAH!

Not a matter of if it will be needed, but when.

We get big rain events from Gulf hurricanes all the way up here in Kansas.


Edited by snrub (09/24/14 01:22 PM)
_________________________
John

I subscribe to Pond Boss Magazine

Top
#388177 - 09/24/14 01:53 PM Re: Where to put the overflow pipes and how large [Re: snrub]
Flame Offline


Registered: 09/12/14
Posts: 1067
Loc: Deep East Texas
Thanks everyone. I WILL have a emergency overflow!!!
_________________________
Dear Alcohol, We had a deal where you would make me funnier, smarter, and a better dancer... I saw the video... We need to talk.

Top
#388183 - 09/24/14 02:41 PM Re: Where to put the overflow pipes and how large [Re: Flame]
esshup Offline
Moderator
Ambassador
Field Correspondent

Lunker

Registered: 01/26/09
Posts: 24029
Loc: Grovertown, Indiana
Here in Northern Indiana in 2008 we had the remenants of Hurricane Ike roll thru. 12" of rain in 24 hrs........

Now think about if you have a 10:1 ratio. That pond would see 7 times (or more) of the surface acreage in water. 10:1, one acre pond, worst case scenario could see enough water coming into the pond to raise it 10 feet in that 24 hr period. Make sure the emergency overflow is sized properly!!!
_________________________
www.hoosierpondpros.com


http://www.pondboss.com/subscribe.asp?c=4
3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).

Top
#388220 - 09/24/14 10:02 PM Re: Where to put the overflow pipes and how large [Re: Flame]
Dave Davidson1 Offline
Moderator
Lunker

Registered: 01/04/06
Posts: 13600
Loc: Hurst & Bowie, Texas
I don't like bottom style drains. To do them, you have to damage the integrity of the bottom of the dam. A siphon will do the same thing without any potential problems.
_________________________
It's not about the fish. It's about the pond. Take care of the pond and the fish will be fine. PB subscriber since before it was in color.

Without a sense of urgency, Nothing ever gets done.

Boy, if I say "sic em", you'd better look for something to bite. Sam Shelley Rancher and Farmer Muleshoe Texas 1892-1985 RIP

Top
#388241 - 09/25/14 08:02 AM Re: Where to put the overflow pipes and how large [Re: Dave Davidson1]
FireIsHot Offline
Moderator


Registered: 02/28/11
Posts: 3875
Loc: Emory TX
Originally Posted By: Dave Davidson1
I don't like bottom style drains. To do them, you have to damage the integrity of the bottom of the dam. A siphon will do the same thing without any potential problems.


Also, it's much easier to add another drain pipe, or repair the one you have if needed. Keep the vent hole caged or protected because creatures of the night will get in them, and trash will accumulate and could potentially keep the vacuum from breaking. I had a huge turtle stuck in the vent once, and dropped the pond almost a foot below pool before I got him out.
_________________________
AL

Top
#388247 - 09/25/14 09:04 AM Re: Where to put the overflow pipes and how large [Re: Flame]
Flame Offline


Registered: 09/12/14
Posts: 1067
Loc: Deep East Texas
Thanks everyone. By "bottom drain" I meant a siphon system that removes excess water from the bottom of the pond and not the top.I will be using a siphon system... Instead of worrying about all the formulas and calculation I read about Can I just go with 10 or 12 inch pipe and be done with it? I understand too small of pipe could be very bad but too big? Is it just because of the price of pipe? Or can you have too large of pipe. My only thoughts would be too large of pipe would make it that much harder to "start" the siphon effect. Thanks for any more advise.
_________________________
Dear Alcohol, We had a deal where you would make me funnier, smarter, and a better dancer... I saw the video... We need to talk.

Top
#388252 - 09/25/14 09:34 AM Re: Where to put the overflow pipes and how large [Re: Flame]
FireIsHot Offline
Moderator


Registered: 02/28/11
Posts: 3875
Loc: Emory TX
Flame, I had a bottom drain until I caged the inlet off for a grass carp permit. I didn't want a blocked cage at the bottom of my pond, so I raised the inlet up. We had it 4' up from the bottom, and elevated 4'from the face of the dam. These pipes will move a lot of water and create a lot of suction, so I wanted to try to make sure the face of the dam wasn't compromised as DD1 said.
_________________________
AL

Top
#388257 - 09/25/14 11:35 AM Re: Where to put the overflow pipes and how large [Re: Flame]
snrub Offline


Registered: 10/05/13
Posts: 5261
Loc: SE Kansas
Originally Posted By: Flame
My only thoughts would be too large of pipe would make it that much harder to "start" the siphon effect. Thanks for any more advise.


It is pretty easy to get a misconception of how the siphon comes into play.

During normal rainfall events it is unlikely it will go into "siphon" mode.

During normal rainfall events the pond will rise to the level the water will simply "run over" the overflow. This will happen with either a regular overflow pipe or a bottom draw style. With a bottom draw style the water column pressure will cause the overflow water to come from the bottom of the pond instead of the top. Both regular overflow pipes and bottom draw systems work the same way in this mode. The water simply flows over the highest point of the bottom of the inside of the pipe, which is the full pool level of the pond.

The overflow system can go into siphon mode whether it is a bottom draw system or an ordinary overflow pipe. For example, I have a simple 8" overflow pipe that is angled down to near the bottom of the backside of the dam. Pretty typical and conventional. It can go into siphon mode once the water reaches more than 8" above full pool and the top of the pipe is covered. The "siphon" volume of water that the pipe can flow is considerably more than regular flow rates because the "weight" of the water, because the pipe is angled down, will cause the water to flow faster. So once the pipe is full with all air out, assuming the pipe is angled downward, it will flow more water than what the same pipe will in a horizontal position (assuming a vortex does not introduce air at the top). This is siphon mode. The steeper the angle down and the longer the drop (higher head pressure or in this case vacuum), the greater the flow the pipe will handle in siphon mode. This is no different for a conventional overflow pipe or a "siphon" system.

Where the siphon system comes into play is the conventional overflow pipe is connected to a down pipe that extends to near the bottom of the pond on the water side. This is where you get water drawn from the bottom of the pond. But until the pond inflow gets high enough to cover the overflow pipe at the top (so no air is introduced), it does not go into siphon mode. It works just like a regular overflow pipe. The water simply rises and overflows, same as a regular overflow pipe, with the exception that the water comes from the bottom of the pond instead of the top. Neither system goes into siphon mode until water completely covers the highest point in the pipe (including the air vent in a siphon system). It only goes into siphon mode when no air can enter.

With a regular overflow pipe that is angled down, the siphon mode stops as soon as there is an air gap at the top of the pipe. Then regular overflow and overflow rates happen. With a bottom draw siphon system, there has to be a "vent" at the top of the pipe to break the siphon. Otherwise the siphon would continue until the pond was low enough where the inlet was near the same level as the outlet. This is why you have to make sure this "vent" does not get clogged - the siphon will drain your pond. In fact, this vent can be purposely shut off just for the provision of draining the pond.

Clear as mud? You may have already known this, but in case you did not, thought maybe this explanation would help. The experts can correct my technical mistakes. Siphon mode is not started, with either a siphon system or conventional overflow pipe angled down, until the entire pipe is covered with no air available to be introduced. In other words, in high rainfall events where the entire pipe gets covered. But the source of the water always comes from where the inlet is. In a bottom draw it comes from the bottom and in a conventional overflow it comes from the top. Hope this helps.


Edited by snrub (09/25/14 11:47 AM)
_________________________
John

I subscribe to Pond Boss Magazine

Top
#388261 - 09/25/14 12:10 PM Re: Where to put the overflow pipes and how large [Re: Flame]
snrub Offline


Registered: 10/05/13
Posts: 5261
Loc: SE Kansas
Originally Posted By: Flame
Hopefuly breaking ground on 2 acre pond in about a week. Please someone simplify where and how deep and how large to install my pvc pipe? I have tried to read everything and look at photos posted but get confused easily. How far from the top of the dam should my emergency spillway be? How large of pipe? How far from the top of the dam should my regular drain pipe be? How large of pipe and should I install more than one in various locations? I would love to have a siphon style but I don't think my builder will know how to design it. Where exactly do I install a "drain valve" if I want to manually lower my water level or drain the pond for some reason? Please understand I need simple answers for my simple mind!! Thanks


As Esshup says, there a no set answers because the answers depend on the environmental conditions your pond will see.

But there are some generalities that will at least give you a rough idea of what to expect. The height of the dam above normal pond full pool level is called freeboard. This height is dependent on things like how big your watershed is, how big of rainfall events you could get in extremes, and how much water your emergency overflow can handle. In other words, the freeboard has to contain any amount of water that could ever flow into your pond that could not get out fast enough to where the water would run over the top of the dam. Because if the water ever tops the dam, it is likely going to breech and destroy the dam. Some extra freeboard also allows for normal settling of the dam and loss of height do to erosion. My 3.1 acre pond called for 3' of dam height above full pool, or in other words 3' of freeboard. My emergency overflow area is 1' above full pool. My overflow pipe is 8". So in other words, during a high rainfall event first the overflow pipe handles the volume as the pond rises up to 8" above full pool. Then the overflow pipe goes into siphon mode which flows more water than a standard horizontal overflow pipe. If the pipe still can not handle the flow the water rises to a foot above full pool where the emergency overflow starts to flow water. At this point I still have 2' of freeboard left. Two foot of protection of my dam. As the water flows 6" deep over the emergency overflow it will be about 15' wide at the emergency overflow at that point and I will have 18" of freeboard left to protect the dam from being breeched at that point. That was the original design and I have actually raised my overflow pipe 4 additional inches when I extended it over my bench area, so in reality my overflow pipe will never go into siphon mode as the water will be going over the emergency spillway by the time my pipe is covered, but I'm digressing into a tangent.

Three foot of freeboard above full pool and emergency spillway a couple foot below the top of the dam is very common in this area for a regular size farm pond. But it is by no means absolute. For example a huge lake that gets flood inflows might have 15' of freeboard. Or a pond that is designed for a watershed project to reduce flooding might have ten foot of freeboard above a very small overflow pipe that allows the pond to rise to high levels during high rainfall then meter the water out slowly down to normal level. As the famous PBF saying goes, "it all depends".
_________________________
John

I subscribe to Pond Boss Magazine

Top
#388266 - 09/25/14 12:25 PM Re: Where to put the overflow pipes and how large [Re: snrub]
snrub Offline


Registered: 10/05/13
Posts: 5261
Loc: SE Kansas
Just to give you another example of "it depends", on my mini forage pond, I only designed the "dam" to be 1' above full pool and the emergency overflow to be 6" above full pool. So I only have 6" of safety before the dam is breeched.

But......... this pond is only about a half of a tenth of an acre, and only sees maybe an acre or two of runoff. It is near the peak of the hill. PLUS, full pool for it is only about 18" above full pool of my main pond which is right across the dam. So even if the dam were breached, the water levels would equalize pretty quickly.

Is a foot enough? I doubt if an engineer would say so. But I think it will be fine and if it isn't will have no one to blame but myself. If it were a big pond with large water inflows from a large watershed, no way would it be enough. The three acre pond I had an engineer design (NRCS). This little tiny pond I did the design myself.

So as you can see, the size of the pond, the size of the watershed, size of rainfall events all come into play of how much dam height above full pool is needed, the size of the overflow pipe, emergency overflow sizing, ect.


Edited by snrub (09/25/14 12:26 PM)
_________________________
John

I subscribe to Pond Boss Magazine

Top
#388267 - 09/25/14 12:29 PM Re: Where to put the overflow pipes and how large [Re: Flame]
Flame Offline


Registered: 09/12/14
Posts: 1067
Loc: Deep East Texas
Thank you SNRUB. It now makes a whole lot more sense to me!!! Thank you,Thank you, Thank you.
_________________________
Dear Alcohol, We had a deal where you would make me funnier, smarter, and a better dancer... I saw the video... We need to talk.

Top
#388515 - 09/29/14 12:33 PM Re: Where to put the overflow pipes and how large [Re: Flame]
Flame Offline


Registered: 09/12/14
Posts: 1067
Loc: Deep East Texas
I just got off the phone with my pond builder. He will be here next Monday to start clearing the area and to get elevation readings. I told him I wanted a siphon system and he is already trying to talk me out of it mainly is because he says we will have too many trees in our area and it will clog the pipe with blown leaves and debree that settles in the pond. I understand you can put the pipe 3-4 ft. off the bottom. He said I would constantly be needing to clean the screen. What do Ya'll think. I do have 25 acres of trees surrounding the area. What is a good method for filtering the end of the pipe? Kind of upsets me after doing all the research here on your website and making my decision for raising lmb and the siphon system he is not wanting to do it that way...
_________________________
Dear Alcohol, We had a deal where you would make me funnier, smarter, and a better dancer... I saw the video... We need to talk.

Top
#388519 - 09/29/14 01:14 PM Re: Where to put the overflow pipes and how large [Re: Flame]
DNickolaus Offline


Registered: 01/26/14
Posts: 334
Loc: S Indiana
Just another point of comparison for you in my pond. It's a little under an acre. Fed by fairly steep 10 acres' runoff only. But lots of water comes out of the ground above it. We get big rains. I have a 12" overflow. A foot above that is the emergency spillway that is far enough to the side that it's over bedrock so it can't cut down. 2 1/2' of freeboard. Not saying my pond is perfect at all, but just another "it all depends" here.

I let my pond builder talk me out of/into things. If you've done good research, stick by your guns or find another builder. If it's someone like Otto who has a bullet-proof reputation, then best listen. A clogged overflow pipe is a crisis, so best address it. There will be floating debris as well so you'd have to take steps that way also. A large area grate/screen would be called for in either location. Bit harder to detect issues/clean near the bottom. Benefit of drawing off bottom water is valid. Though if you turn it over regularly via aeration, that argument gets weaker.

Top
#388538 - 09/29/14 02:40 PM Re: Where to put the overflow pipes and how large [Re: Flame]
Flame Offline


Registered: 09/12/14
Posts: 1067
Loc: Deep East Texas
Thanks DNICK,I was planning on aeration later after built and knew where I had to install my electric pole.Is your emergency spillway 12" also? Have your heavy rains ever had to come out the emergency?Any suggestions on how to design a screen? How would you test for a clogged screen later? If the water has never got deep enough to overflow? Is there a means of "getting to" the screen if it clogs without going diving? Just trying to be prepared. Now is my time during the design stage to figure this all out.
_________________________
Dear Alcohol, We had a deal where you would make me funnier, smarter, and a better dancer... I saw the video... We need to talk.

Top

Today's Birthdays
Brett, CATMANDEW, Dennis, RERBABS
Recent Posts
My pond full of outcast
by bigpullerman
Today at 01:25 PM
They're back!
by Zep
Today at 11:24 AM
Pole saw
by JKS3613
Today at 09:48 AM
What did you do at your pond today?
by Flame
Today at 07:56 AM
What a difference a year makes.
by Audrey
Today at 04:56 AM
What are the chances?
by Audrey
Today at 04:52 AM
It's that time of year, again....
by Audrey
Today at 04:48 AM
Hall of Fame 2018
by Pond Boss
Yesterday at 10:50 AM
Flocculant effective clearing
by DannyMac
Yesterday at 10:14 AM
Fish delivery
by Mfitzs70
Yesterday at 06:40 AM
Newly Uploaded Images
My recent haul
Hello From Lufkin Texas!
Cant seem to Identify what this is.  Any thoughts?
Evaluating and adjusting Fish populations and ID
Vegetation ID
Our new pond

2014 POND BOSS INC. all rights reserved USA and Worldwide