Good to see the replies, thanks. I could just be seeing evaporation and i'm just overreacting. That being said, i'll loose over 18in in a month (est) on average this year in a .89 ac pond. I can't be the only one that would think its just evaporation with that much gone, right? Yes, i have oak trees on 3 sides within 25ft or so from the waters edge. Two of them are 4ft thick at the base.
Unfortunately when i was digging the pond i only had access to the dozer for a compactor (no sheepshead roller). With that said, i feel i did as good as i could with what i had. I estimated that for every 2ft of clay i put down i would compact it with the dozer. My calculations say 2ft of loose clay compacted equates to 12-14inches of compacted clay. Following that calculation i have an estimated 5ft thick "wall" of clay that covers the soil in the top 5ft of the pond. (I drove that dozer long enough during my "compaction sessions" that the ceramic tiles in some areas lifted from my concrete foundation in my house. Vibration is the only thing i can equate it to get tiles to "lift". I had no water leaks of other obvious things happen that would cause complete 12in tiles with no cracks to come up in hole pieces. The house is 50yds or so from the pond.)
Esshup: Can you expand on how to test the evaporation rate, as you were mentioning?