When I 'WORKED' for a living,,, I built 4 or 5 ponds N & W of Mosquito,,,,, and some of those borrow-pits along Rt11.
Maybe you cold RENT an excavator, & build it yourself,,,,, IF you have a close place to put all of the fill dirt!
(lol,,, there's dozens of old retired operators out there, that could/ would help ya out!)
#1,,,,, HOW BIG?
do a dirt/ clay/ perc depth test, at least at all 4 corners! Search for rock, sand, clay & water. Aerators? Wind mill, electric, solar pump, waterfalls?
ideas;
http://www.digsdigs.com/53-cool-backyard-pond-design-ideas/
#2,,,, IF you have a small creek, spring, artisan water well, & your thinking of using those sources for feeding/ filling your pond with the water, HAVE THE WATER TESTED FIRST! check for farmer's field run-off? OLD, Near-by septics.
#3,,,, and, if possible, NEVER run a creek, spring straight into your pond. ALWAYS build your pond off to the side. Use a gait to direct the 'tested' creek waters,,,,,, refill/ flush your pond when needed! I'll even suggest a pre-pond/ hole,,,, up-creek. To collect run-off sediments, before it gets into the pond.
#4,,,, Try to incorporate a bottom drain pipe, if possible. 'FLUSH' out the first 2 or 3 year sediments.
Use an over sized dam drain pipe with re-moveable screen or mesh cover, for cleaning,,,,, and maybe build a huge rock/ rip-rap overflow waterway along side.
I've seen quite a few dam BLOW-OUTS, when the pond was built in a natural run-off waterway.
If you like,,,, care,,, I will send you some Google Maps pictures of some ponds that breached, or filled with muck.
You'll easily see why.
I got a million of 'em,,,, just some starting ideas.
Good Luck