...another thought
I would maintain concerns for the overall, general location of the beach. When it is confined to a (nearly) enclosed area, vegetation in the water might surround the area quickly. Any water depths of 4 ft or less are presumed to propogate weeds and cattails. The actual beach zone, with the geo fabric, will be weed free, but areas adjacent might propogate an "ick" factor (not to be confused with ich). If the zone you selected has a good, continuous depth as you face out from the shore, then the worst that can happen is you will have weeds on either side, but you can swim directly out to deeper and cleaner/clearer water. If your opposite shoreline is too close, you will be trapped for swimming.
Not sure I understand. I do plan on putting in a liner under the rock, one to keep it weedless, secondly to keep the rock from sinking in the mud. Basically there will be 3 banks and an open side to the rest of the pond. Of those 3 banks, one will be beach shore, the others will be the same as the rest of the pond, vegetated banks.
