Pond Boss Forums INTRO Questions & Observations Seal Spring in Pond Basin ? See post with pictures

I have a pond nearing excavation completion.
Size is approximately 0.4 acres, 10' deep at the bottom, primarily spring fed, about 5 gpm. Watershed is probably less than 20 acres and I rarely see much runoff.

6" SDR 35 pipe is placed through the bottom of the dam/embankment.
Guess it could have been higher, but that's where it's at.
Ready to place elbow and standpipe on.

Do I need to anchor the standpipe? Was thinking of auggering a telephone pole at attach to.

Also have a length of 15" smooth lined corrugated plastic pipe that I was thinking of placing over top of the 6" to act as a trash guard and pull water from a lower depth.
Any suggestions on what depth to pull the water from? Was thinking of maybe just placing on the pond bottom and drilling some 4" holes through this to allow for water to flow in.
Noticed someone else here just ran 2 pieces of all-thread perpendicular through the sleeve and standpipe and held the sleeve off the bottom.

Ideas? Suggestions?

bump

If the pipe's already down there, I'd draw water from as low as I could get it.

I've always liked the large upper tube suspended over the standpipe approach you mentioned myself.

Have you considered pouring a concrete base for/around the standpipe?

Hi wivell,
I don't know if this relates directly to your plan, but it might spark some ideas or creativity. Go to the bottom half of this page from our website. The engineering is borrowed from 2 smart pond guys...Mike Otto and my dirt-guy.
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(edit) I just re-read your request and realized you're going for the stand pipe as your outflow. Sorry for the misdirection.

Thanks Theo.

I didn't want to place concrete around the standpipe just in case I ever wanted to pull the riser and drain the pond.

The excavator has an auger for his backhoe. I'm thinking of augering an old telephone pole in and achoring to late.

Maybe I don't need anything? Just concerned the riser would want to pop out of the fitting without being tied down somehow.

I think anchoring is in line. I'd want something just on general principles.

Well I'm making some progress

Standpipe was installed on 6/6.

Depth of water at this point is a little over 3 feet - not bad considering we receive virtually no runoff into this pond. Not a bad thing if and when the pond fills - should stay clean/clear I hope.

We've had 2 real hard downpours since the standpipe was installed and all I've noticed is a little cloudiness to the water coming from the "Spring" pipe. There was on old hand dug well about 200 from the pond. We dug above this and installed some corrugated/perforated drain pipe and then transitioned to the 4" SDR 35 you can see near the dock piers. I plan on trimming the piers down to the proper height for the dock and then attaching the SDR pipe to the piers.

My biggest concern right now is a small spring seepage - my pictures aren't the greatest but the seepage is located near the red flag. I haven't got the level out the check yet but I think this seepage is at about the 5 foot water mark.

Questions:

1) Should I try to seal this? I'm concerned once/if the water rises above this the flow will reverse direction.

2) If I try to seal - when and how? Seems that the water will want to just continue pushing out right now. I could still get a small dozer in there and pack some clay on it.

3) Dock Piers - should I seal around those? It seemed there was a layer of soft rock below the clay surface and then more clay. When we dug the holes the filled with water pretty quick so I had some seepage from somewhere.

Thanks in advance to everyone who replies. There are some great minds and friendly folks on this site.

Yes - it was foggy in western PA this morning and not bad focus on my camera....

Wivell...

Being concerned about the spring going in the opposite direction is a well founded concern because it is likely. The water will flow in the direction of least pressure. If there is more pressure coming from the pond, it will act like a drain. As far as sealing it goes, I will leave that to more experienced people. I am curious to hear their response to your pier question as well. I would think packing the holes with a foot or more of clay would be sufficient, but I have no experience with that.

Ezylman,

Thanks for the reply.

Yep - I'm expecting to need to seal the spring.

The guy who excavated for me thought maybe I should wait until the water level reaches the seepage point and then try to hand seal. He was thinking that trying to seal it beforehand would be tough - the water would just want to push out there or elsewhere was his thinking. Maybe I need some bentonite ???

He's an older gentlemen - about 75 - who has "been there done that". Can't say he's a pond expert but he's drilled water wells, installs cattle troughs all over hillsides, works around natural gas wells, can fix about anything made of metal with his welder, lathe etc.

Very little formal schooling but one of the smartest people I know.

Curious what other have to say about the pier holes too.

My 12 year old son is dying for this thing to fill. Hated to take the air out of his balloon when I told him it wouldn't be full this Summer. My guess is the pond holds around 500,000 gallons. The groundwater/spring flowing through the supply pipe has been running steady at about 2- 2.5 gpm. That's about 3000 gpd, or about 6 months worth. If we're lucky we won't have much seepage & evaporation and the groundwater will keep coming.....

Scott

Well, if it makes your son feel better, flowing at 2-2.5 gpm will do a pretty fair job of giving you some depth. That is close to 3,000 per day. As long as your evaporation is less than 3,000 gallons per day, the spring will keep filling it. It won't fill it up real fast, but he will still be able to swim in it and you could stock FHM and maybe BG fingerlings in another few weeks. That is as long as you don't need to drain it to seal the spring and put in your piers. As far as what to seal it with, I am ignorant on that count so I will wait and see what other people have to say.

where is that spring in relation to your dam?
Don't lose any sleep over that "spring"
seal it one place it'll pop out somewhere else, it's just ground water finding it's way out from above... an impossible excape route for your pond water that is below the level of the "spring" higher starting point. If you do have a leak or seapage, it won't be from that.

wivell,

If your pond is surrounded by higher ground (even at quite a distance), there's a fair chance the spring won't run backwards.

If you start packing the seep, and it's real hard to stop the water, that's good news. It means the spring has pretty good pressure and may never run backward. If it's easy to pack and stop the leak, that's good news too.

If you had a neighbor with a well, maybe you could buy some water and fill it, and see what happens.

Bill,

I hope you're right. I don't think the seepage point in the pond and the groundwater/spring I have piped in are one and the same.

The image below is pretty crude, based on Google earth winter satellite image, but shows the location of the original hand dug well (small blue circle), the grounwater supply installed (green line), the pond perimeter (heavy blue line) and the approximate location of the spring (red dot).

The hand dug well to the West was about 10 feet in elevation higher than what I hope the full water elevation of the pond will be. The area immediately to the south of the pond is a pretty steep hillside, probably 2:1 slope rising about 75 feet. I have no way of knowing where this spring seepage in the pond basin is coming from though. Probably from the higher elevation somewhere....

Bob,

The pond embankment was construction in a natural swale so existing grade on 3 sides is higher than the pond. The embankment is about 13 feet high. I still need to construction the emergency spillway in the SE corner.

I hope you're right about the spring not going "up" the slope.

I have a hard time believing the spring would continue to push water into the pond when it's 5 feet under water though. Hoping finished depth is +/- 10 feet, seepage point appears to be at about the 5 foot elevation mark.

Scott

Wivell...

Water can't flow up-hill unless there is a pump pushing it. As long as the source of the seepage is above the waterline of your pond, it won't flow backwards. If it was me, I would leave the spring be for now and see where your pond tops out at. It could be a good way to ensure that you keep a full pool. If it becomes and issue, drain off 5-8 feet of water and try to fix it.

Ezylman,

I agree it can't flow up hill.

I'm just not sure where this seepage "layer" originates from that is currently providing water to the pond.

Maybe I'm wrong, but it could be a continuos plane/layer going far away from the pond and subsequently carry water away with it when the pond tries to overcome this elevation. I don't seem to have water entering on the opposite slope (north side of pond) so who knows.

I probably still have a month or 2 before I'll know unless we get a real gully washer of a storm that puts some water in. Otherwsie it's just steady as she goes with the 2 - 2.5 gpm from the pipe.

bump - looking for more opinions

I would want to pack a foot or two of clay over the seep. Even if you don't get it sealed, it should slow any future outflows down to slower rates.

While I was bringing clay in, I might tamp some around the base of the dock posts too (time allowing).

Thanks Theo.

That's what I was thinking - some clay over the spring seep should at least slow down a bit.

And I guess the ole "While I'm at It...." would apply to the pier spots as well.

Time to get the dozer back....

While excavating my barn site we came across a number of seeps/springs. They all seemed to run horizontally or uphill (flowing downhill). If I read your post correctly the land slopes upward from the seep.

I looked into developing the seeps for livestock watering and came across one method that might work for you.

Drive a well point or piece of 3/4" black iron pipe (with a threaded cap on both ends) into the ground horizontally starting at the wettest part of the seep. Pull the pipe out, remove the caps and reinsert it a foot or two short of the original driven depth. Compact the dirt around the area where you inserted the pipe as much as you can and as deep as you can. As long as the end doesn't get plugged the water should follow the path of least resistance and flow through the pipe. Then thread an elbow on the exposed end of the pipe and point it upwards. Thread another length of black pipe into the elbow so it also is pointing upwards.

If the vertical pipe fills with water to your full pool level then the spring probably won't reverse direction when your pond is full. If the vertical pipe doesn't fill you just wasted 20 bucks in pipe and 2 hours labor.

I'd compact the area with clay regardless of the results.

jsec,

That sounds like a good idea. Where in western PA are you located?

Scott

I'm about 15 miles outside of Monroeville.

Don't forget the pix if you try the pipe thing.

jsec, I sent you a PM.

Thanks to all who answered.
Looks like I need to add some clay to a few potential problem areas and keep my fingers crossed.

Got a good start on the dock on Saturday.
One setback though - I notched the old telephone poles for the joists that will support the dock surface and now I have a nasty rash - chemical skin burn from the sawdust !!!!

Oh well, live and learn....

Jsec,

If I get a chance to try the pipe idea I'll take some photos.

Scott