Is there a ratio of how wide the core needs to be relative to the width of the dam. After perusing a few of the threads here, I was surprised to see that a core can be as narrow as a couple of feet. For some reason I thought it would have to be 4' or so to be effective. What is the narrowest one can be and still work?
I am meeting with a pond builder to help me with my dam problems that I discussed in the dam seepage thread and I'd like to be able to have some options to discuss with him. Building a core 18' or so in width sure seems a lot more affordable than what I had in mind.
