Asgrd, first welcome to the forum. I spoke with a retired NRCS man today. He retired 2 months ago, so info is current.
What you have been told IS correct. To have an "engineered" dam you would have to hire an engineer. An engineered dam is only required if the height of the dam exceeds 35 feet in height. This info only pertains to Federal requirements, I don't know about state or local regs. Unless your NRCS guy is lazy, his job is to come and drill core samples and find the best location for you to place a dam AND if he is not lazy can recommend qualified equipment operators and even supervise the construction---That is what my local retired NRCS agent did for me and others. The services that I just mention the NRCS CAN do are all free.
I hope this helps a little.
For a WHOLE lot more info on a pond, get the book
Perfect Pond....Want One? here.....
Pond Boss Books. I can't imagine needing an engineer for a dam as small as what 1 acre would require. Usually an engineered dam is for VERY VERY large lakes.
Also, if the area you had cleared was dry BEFORE clearing, the spring probably has very little pressure. If you put the spring below where you want your water level, the spring MAY act as a drain.
Best of luck and PLEASE keep us updated. Pictures are always great as well!
