List your priorities. I presume that the pond will be pretty high on the list. That would mean it should be one of the least likely facets to face compromise.
Cutting a 4 acre pond in half (or quarter, as it were) would seriously compromise the aesthetic value, IMO. Not to mention that putting a earthen bridge thru it will create 500 more linear feet of shoreline and shallows that will need maintenance. Not to mention that you lose considerable water volume due to the mass and slopes of the earthen bridge.
We had to deal with a draw that I wanted a roadway across. Granted, it's not a driveway, but it could be (already supported passage of loaded tri-axel and a front loader concrete truck with about 8 yard of 'crete). Anyway, it's not brain surgery as long as the culvert is correctly sized, pitched, and correctly elevated. You are going to be looking for a close place to off-load soil waste. Your draw is screaming "fill me".
Think about every time you look out over your 4 acre pond. Draw the pic in your mind of both options. I know which one I would choose.
