Jscummy,

You have listed several of the dimensions for your project. However, the dimensions you have mentioned only make a small difference, and you have not listed the critical dimensions.

How high above the surface level of your pond is the tee at the top of the hill where you pour water?

34' is the maximum theoretical elevation change at sea level. 20-25' is around the max in the real world. The siphon actually operates using atmospheric pressure to "lift" the water. If you are at a moderately high elevation in the mountainous parts of Kentucky, then your max lift possible over the top of your hill will be even less.

The second "critical" number is how far the end of your outlet pipe is below the end of your inlet pipe in the pond. For relatively short pond siphon runs, being about 4' lower at the outlet is usually sufficient to set up a good siphon.

However, you are running a lot of "horizontal" pipe to get up to the top of your hill and then back down to the end of the outlet. Water running through a pipe loses a little bit of pressure due to friction along the walls of the pipe. If your outlet is only 4' lower than your inlet, you may not be able to establish a siphon with your long pipe run.

You did not state the diameter of your siphon pipe. The larger the pipe, then the less the frictional pressure losses - and the easier it is to establish the siphon action.

You have received some excellent siphon advice from the posters above. Hopefully, applying those fixes will get your siphon operating properly! I was just adding some additional siphon requirements so you can be sure your siphon will function in the real world after you get all of the "mechanics" set up correctly.

Good luck on your project! A 5-acre pond that is 15' deep sounds like it could be a beautiful pond when you finish your silt removal project.