Hey big...sorry for all your concerns. Don't get in too big a hurry to do anything just yet. You say you're in a drought condition and have only lost 1.5 feet this summer? We're in (just a bit below, actually) normal conditions and I've lost that much from my little 1.7 acre pond. We've had plenty of rain for crops, but no real runoff this year.
Could that not be the actual problem? 20 gpm inflow? I've done some calculations that show I'd lose (on an average summer day) about 25% of that just in evaporation. You should see quite a bit more from your pond...maybe you just need to see what an average year will do for you...whatever that is. And, if we ever see another one....
In a lifetime, the average driver will honk 15,250 times. My wife figures I'm due to die any day now...
