I came across this item in Sport Compact Magazine. They had a NSX on a dyno with the intake stuck in a fish tank. The Air Bypass Value stops the water from making it into the engine.
AEM Air Bypass Valve
AEM has developed an Air Bypass Valve for its Cold Air Induction Systems. This valve installs on the intake pipe along the same axis as the throttle body and eliminates any chance of water ingestion should the filter element become wet from rain, hail, sleet, snow, flood or any other scenario where the filter element could encounter or become completely submerged in water.
http://www.aempower.com/new_products_f.htm
Don't think we can use it.