I have a one acre pond which has been filling from a well. The depth has stabilized at six feet with the bottom completely covered. The existing pump is delivering 11 gallons/minute and since it is a cool spring here in Michigan I am assuming all 11 gallons is seepage. I can calculate the evaporation rate for this summer from reading the PB forums. What I am uncertain about is the effect on Darcy's law due to the depth of the pond. If the ultimate depth is 18 feet what factor should I allow for additional seepage rate due to the increased pressure? For example, if at the present 6 foot depth the bottom seepage is 11 gallons/minute should I use 33 gallons/minute when the depth is 18 feet? Once I confirm this I can calculate the additional seepage of the sides and proceed. Thanks