you would need a pipe to move the water from the pump in the catch basin back to the pond, and you probably won't want to look at it, so it should be hidden or covered with something decorative like a fountain.

Hi
Sounds more like a fountain than water garden or fish pond.?? Would be concerned with the fish going over the edge? Those infinity edge pools look fantastic but would require careful sizing of the pump to water flow or the effect would be ruined. There are ways to figure that of course but beyond my knowledge lol
Hope you show us some pix sounds like a fantastic project!!! gary

I would suggest you talk to swimming pool contractors since they do infinity edges. It is not something I've ever seen in a pond. It does sound like it would be great with your home. I love all those Mid Century Moderns in Palm Springs.

I've done this type of build several times, it's my preferred way to build a pond. Main pond over flows into a smaller basin which pumps water back. My overflow would always be a stream or skimmer, but same concept. Lots of benefits to this type of design imo.

Couple of keys...obviously the infinity edge has to be level...not, "I put the level on that and it looks level", I mean dead level. Really hard to do. If the mason really understands this he can do it. If he says "yes I understand what level means" he may not. If it was me I'd test him. He stood be able to explain why, in detail, why it has to be dead level. Everyone is happy when finished and perfect. Otherwise there's bad feelings and finger pointing. Better for everyone to be happy.

A larger pump can some what fix a less than level edge. But the sheet of water will be jacked up. If the sheet isn't seen and you don't care about that then less than level can be OK, will still look like an infinity edge.

Wide sheets take big pumps. You can do a drip edge type deal, still looks like an infinity edge but you don't have the sheet to worry about. Sheets are very difficult. Most infinity edges are viewed so you don't normally see the water coming over the edge, but I don't know the goal in this case.

Another key is the catch basin has to be sized to the pump size. When the pump goes on it takes a while for water to fill the pipe and then fill the pond enough so water overflows the edge. During that time the pump is sucking water out of the basin, level goes down, pump goes dry, end of story if basin is too small. Even if the pond is filled to the top it still has to be filled more to over come surface tension. Could be talking about 100 gals of water.

This can be fixed somewhat by sticking a hose in the pond and filling until it over flows and the basin is full and then turning on the pump. You may even have to keep the hose running. Downside is that when the pump is turned off the basin will overflow. So it's a good idea to install an overflow pipe in the basin and direct flow away from the pond and house. Muddy damp soil can lead to foundation problems. 1" of rain in a 100 sq ft pond will result in 10" water level increase in a 10 sq ft basin. Overflows are good, and very cheap.

Last key is all evaporation will appear in the basin. Same deal as the rain only in reverse. IMO the basin should have an auto fill to keep it topped off. I like a regular horse trough automatic float value ($7-15), but fed by a sprinkler valve set to go on for a few minutes everyday. The float valves don't work forever and the sprinkler valve is your insurance of minimum flooding. Unfortunately the horse trough valves only last a couple of years, but are easy to replace. I'd buy a couple.