Pond Boss Forums POND CONSTRUCTION Renovating a Pond or Lake? Drainage culvert

So, here is the problem: my pond has a culvert so that the pond can drain after heavy rains. I don't want to stock any fish because I'm afraid that when the pond needs to drain, fish will get caught in the current and flow out of the pond. Any ideas on how I can block the fish from exitng my pond through the culvert? (Need to figure this out so I can stock some fish!!!!!)

Put some sort of grate on the end of your culvert but it may catch trash if you experience heavy rains. Make sure it has plenty of holes so you do not restrict your water flow greatly.

That pretty well covers your options lol.. Or cage your fish until they are plenty big enough to fight the current towards the drain.. I thought about putting something over mine before I figured that my pond is pretty well balanced with absolutely no management so why mess up mother nature..

I built a 12' by 12' dock over my culvert and enclosed the bottom from the dock to the ground in 1" by 1/2" wire fencing. The large surface area of the enclosure has prevented clogging while retaining larger fish. Fry still wash through.

Is the dock movable? What if you have a culvert problem?

I have a trap door in the dock floor, but it was intalled to regulate water through a stop-log structure. I have a plastic culvert and have never had a problem with it - Not much to go wrong with a plasic pipe.

One of my friends has told me to weld on expanded metal. Is this a good idea? Also, how big should the holes be in the grate?

If you put a grate on the end of the pipe, be prepared for blockages unless you never have debri inyour pond. Clogs will typically happen during flooding when you need the drain to be clear.

RAH is absolutely correct. There is a lot of information in the archives about this and the minimal impact the lost of fish is in most ponds. The destructive effect of having debris block the outlet and causing dams to wash out and ponds to be destroyed will be remembered and paid for long after the loss of a few fish.

I think RAH has the right idea. You need as much surface area on the screen as possible. If you just weld a screen over the spillpipe you will constantly be clearing debris off of it.

What about putting some expanded metal out around the pipe, rather than attached directly to it? Kind of an upside down "U", where the open ends contact the dam, and the curve travels out around the open end of the pipe? Let it stick up above the normal water level a couple of feet, or whatever you deem neccessary.

As far as hole sizes, how big are the fish you wish to retain? On the expanded metal, I don't think I would want any smaller holes than 1/2", or maybe 3/4"

Listen to Bing.
Your only concern should be for sticks and crap slipping into the spillway pipe and jamming up and clogging it. This requires a well engineered spillway guard that will catch the floating debris, but not stop the water flow.
Regarding the fish, don't sweat it. Lusk says that most fish hunker down and won't be found near a raging spillway pipe.

We have a pond with t-posts and something similar to chainlink across a spillway. But during a major flood, this structure which stood straight up now lays almost flat. Personally, I would not worry about fish loss through the pipe.

I used to think that my fish wouldn't swim through the 4" pvc pipe that is used for the low drain on the pond I raise HBG in. I made a fancy expanded metal screen for the main, 12" vertical spillpipe just to prevent their escape. Didn't give a thought to the puny 4" horizontal pipe. The water level was below it anyway when I stocked the 3-4" fish. March, 2009.

Then, two weeks after stocking, we had a big rain which brought the water level up.

A week later, we were fishing in the pond below the HBG pond, which receives it's overflow, and low and behold, my son catches a HBG. They were never stocked in my other ponds, and no GSF are present.

That was a couple years ago. This spring, I noticed a large HBG sitting on a nest in the lower pond. How many escaped? who knows.

I USED to think they wouldn't get near the pipe. Now I know better.

I don't know what kinds of fish Titan50 wants for his pond, but I would hate for a non, or limited reproducing species, (trout, HSB) to get flushed away because there were no provisions to keep them from entering the spillpipe. If it's the usual LMB, BG pond then I would say the effects would be minimal.

I'm not arguing.. fish go through the pipe.. I noticed hundreds yoy bass and bluegill in a big area behind my pond where the culvert drains. Thing is does it matter? In your case where there's another lake downstream with a separate fish stock, obviously it does matter and you should definately try to screen everything in to separate your too ponds.. In my case mine wash's into a creek and and losing 100's of yoy bluegill don't effect my pond at all, bass loss prolly does but 30 yrs of no management and a good quality stock of fish I can't arque with mother nature..

I'm in agreement with you, BGK, and that's exactly my point. No two scenario's are alike. Without knowing Titan50's choice of fish species, and his water's drainage layout, who's to say that prohibiting fish escaping shouldn't be given more than a fleeting thought? A species that reproduces in your pond will probably replenish itself. Not so for HSB, as an example.

If his pond drains into a creek, and he stocks fish wich are not normally found in this creek, how does that come into play?

Too many unknown factors to make a snap decision here, me thinks.

I would like to stock LMB, CC, and FHM. I already have some BG and GSF. The spillway drains into a 6' by 6' pool that is about 6' deep. From there the water flows down a creek. So if I were to stock adult fish the only fish that would go through would be the fingerlings and fry right? Before we drained our pond, I was always able to take a fishing net and scoop out fish that went through.

I think it would depend on what size culvert you have, and what type of grate you choose to use, as to what size fish could escape.

In my opinion, the key is to not screen off the end of the pipe, rather screen off a bigger area AROUND the end of the pipe.

I think you will always lose some fry, but in your case, with the types of fish you listed, it shouldn't be a problem. Your LMB, BG, GSF?, and FHM will reproduce in your pond. The CC may, or may not. They never have in my ponds. The FHM may escape through the pipe, if they survive predation by your LMB.

What kinds of fish are present in the creek now?

Sprkplug, do you have some cavities in your pond such as old tractor tires or round concrete culverts for the CC do reproduce?

Up to this point I have never provided artificial nesting structures for my CC. Their numbers are low, which suits my purpose just fine.

However, just recently I have decided to utilize my smallest pond as a CC fishery, as my two boys love to catch them. I stocked 25 6-8" cats a couple months ago, so I may experiment with trying to provide suitable structure for them. Thanks for the ideas!

Basically it is just a drainage creek. I couldn't tell you how far it winds along. It is just there far the water to go somplace.

It sounds like the creek might exist solely because of your pond, not as a pre-existing body of water. Perhaps more of a drainage ditch, than a creek?

Somewhere down the line it may empty into another BOW, or it may just runoff and dissipate.

This thread has given me a lot to think about. I'll post my thoughts in a new thread so I don't hijack yours!