@huskerduck,
Yep, the inlet and outlet of the siphon spillway are at the same elevation. I know this, from one nice side benefit I got with the construction of the levee. The dirt guy installed a level straight pipe of 6 inch schedule 40 through the bottom of the levee as he didn't want the pond to fill as he was brining the levee up to grade. The siphon inlet/outlets are even with this pipe.
