i have to agree with ric s. it sounds a lot like my experience. had a spring in what was to be the 26 foot or so deep end. it was putting out lots of water in middle of summer (is the spring producing in the heat of summer?) i initially was concerned like you were, and had the dozer guys pack 2 feet of clay over the spring. overnight it had pushed through it...they wound up building a small levy about 3 feet high to contain the water so that they could work in a dry area. when they filled in the dam, the spring was about to start pouring over the temporary mini levy! so, if your water source is running water in middle of the heat of summer, and you pack it and it busts through, my own experience is..it will add to your pond and not back flow somewhere. the water level within a year was 23 feet. no major leaking problems. i could also drive around in the boat and actually feel the area that was cooler around the spring "central" compared to the rest of the pond. good luck. hope this helps. mark
