Glen, mine is 17 to 20 ft. deep at Bowie. Or started out that way. After 3 years of drought, mine was down 7 ft. It is a little over an acre but in drought times it was about 1/2 acre. Maybe less. Fish management is impossible under those conditions. It's hard for me to say anyting is enough. I would go deeper and also see if there is any way to raise the dam enough to flood more land. Another thought. You can start off with 10-12 ft. but if you have any sand in the sandy loam, it will end up in the pond after washing from the sides and from the surrounding area. Thats why flooded creeks are muddy. Mine is about 1.5 ft of sand at the bottom after 3 years.