Cost to build a lake?

Would like some input on what the cost should be to build a lake that is 450 X 350' in size with 20' of average depth. The site is 3-8% grade, and will require appox. a 28' dam on the low side appox. 400' in length. If I am figuring correctly, around 120,000 yards of dirt will need to be moved?? I would like some input from others as to what a rough cost would be to do this. There is a couple feet of topsoil and plenty of clay below that to work with and no rock will be encountered. Please advise as to what equipment would be best suited for this project. Thanks

Cost to build a lake?