The big problem with a spring filling a pond is that if the spring is below the water level of the pond you cannot install a one way valve on the spring. When the water pressure in the ground is less than the water pressure in the pond the pond will drain........
That type of pond is also called a groundwater pond.
Thanks. I had no idea that springs worked this way. I assumed water would bubble up and fill the pond to ground level!
On one of my spring fed ponds, I used a backhoe to core the areas with springs up to the full-pool level of the pond. Only when the pressure in the ground water allows the spring to flow/seep over this core, will it fill the pond, and it prevents the water from leaving the pond. In essence, it is a one-way valve. So far it has worked very well, although in last year's drought, that pond did drop two feet. My newest (incomplete) pond also has springs and I am not planning to core in front of them. I may regret this later...
Good to know. I'll report back what I end up finding after digging a few test holes.
