New Drain Design

[Sam1969]

you could use soft tubing for the inner tube, solving the problem of fitting in the 90.

[Nate]

Why wouldnt you just drill the two holes if you are still in the concept phase...make for a breeze plumbing it...might not be as cool, but much easier...

[Myka]

Check out Herbie style drains. If you're going to restrict flow with a gate valve, you're best off using a second "safety" drain like the Herbie's do. Interesting idea, but my first concern would be how quickly that would likely plug up, and as Stir Crazy stated, it's a definate likelihood.