Hello, My name is Vic and I am in the process of researching the repairing a Monk Spillway. My pond is aprox 60-70 yrs old and 2.5 acres with 3 spring that feed it. My issue is the box is leaking and I have not been able to get it stopped. I never intend on dropping the water level, so I am considering putting in a 6" pipe and filling the box with concrete similar to this design . This pond does not have a run around or emergency overflow pipe.

Thanks,

VC

Welcome to the forum VCooper!!!

I'd estimate a stand pipe could only handle about half to a third of the water volume your monk box can handle. Are you sure it is the monk structure leaking and not the board seals?

If you can see cracks, and have good access to the cracks, and the structure is made from concrete, you can use hydraulic concrete or good quality sealing paint to seal the box....

Rainman ,
Thank you for the reply.
The issue I have is it appears to be leaking in a corner and at the 3rd 8" board.
One thing I neglected to mention is the dam is a county dirt road. They were given the ROW, but had to maintain the discharge pipe up to the box. About 30 yrs ago the discharge pipe was replaced by the county its located in and they built a coffer dam directly in front of box and it covers the bottom 3 ft of the box. All this was none of my doing, Ive had it aprox 25 yrs. It was handed down to me from a family member. I can go to a larger diameter pipe but, can't find the proper information to base a reasonable determination on the correct size. I've got to do something in the next couple of weeks or I may lose everything in the pond .
Another issue is I've had someone tamper with the spillway before. I think it was a guy I had prosecuted for trespassing and fishing w/o permission , but can't prove it. The locks were cut and several boards were pulled and tossed in the water, which is why I would like to do a standpipe to prevent this from happening again.

I will be repairing a similar setup soon, but instead of a monk, it is a conventional storm drain vault....2 sections of 30" concrete pipe are leaking at the joints and the top leaks at the 4'x8'x6" slab used at the top for vault access and trash rack. A coffer will be built here also.

It sounds like you are going to have to go that route also, rebuilding a coffer, and maybe the box. Do you want to still be able to change pond level? If not, you could pour a box around your current structure...

No , I don't want to be able to adjust the level anymore. It hasn't been changed in 60 yrs except for the time the pipe was replaced and the spillway was tampered with. I put in a call to the Water Conservation office. I also found a vendor that has some 18" double wall corrugated plastic pipe and a 90* elbow for around $400. So this may be the route i take. I'll update after I talk with the WCO.