My first guess would be a thermocline, but I guess a spring would also be possible. This pond does lose some depth during the heat of summer when things get dry, but I suppose it could be a spring that just doesn't produce enough to keep up with evaporation. But, if it's not big enough to keep up with evaporation, I don't know that it would be enough to create that much of a cold zone either. Just an amateur guess on that point though.


Todd La Neve

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1.5 & .5 ac ponds - LMB, BG, RES, YP, GC, HSB