The sneaky and lame way to do this is to throw a body into the water off the side of a building:
https://youtu.be/Gqq_3qRlx4M
But if you want to do it legit, climb your way on top the Wang tower and there are plenty of objects to toss off the top of it. Make sure to jump as high as you can and throw it at the peak of your jump, and the cheevo should pop quickly.
https://youtu.be/AHp1Tn34OP0