I'm far from an expert, built 2 ponds. Let's look at basic math . 3" rain in one hour X's 180 Acres = 540" of water on one Acre. 2 Acre pond , 540" of water divided by 2 = 270" of water divided by 12" = 22.5' of water hitting your spillway ? I'm a bit amazed dam held at all.
Any chance of building 3 more ponds , one on each wet creek, divide up water shed into 3 60's roughly , instead of 1 180 Acre ? My 2 Acre pond stays quite full in western Okla prairie , with 45 acres of water shed , then overflow drains into 2nd 2 acre pond that stays full from 1st ponds overflow , plus 6 additional acres that drain around upper pond. Hoping this made sense. I'm just amazed 2 Acre pond can handle 3" flow from 180 ACRE water shed. What will happen if you get 9" in 3 hours over night ? it'll make a tsunami look like a water park. Experts will correct my very basic math, but I think it conveys the basics. See what topping will be like during Hurricane on your dam . I so hope the experts all say, FA , it doesn't work like that , and he has plenty of pond for the water shed.
