New polytunnel, waterlogging

Hi all, recently I've been thinking of getting a polytunnel, to cut a long story short, the land that it's going on which is the only place big enough is prone to heavy waterlogging in the winter months. I've dug into the ground n made a big enough hole at the lowest part an waited a week or there about an yes after lots of rain it is filled to the top. Now im putting raised beds in the tunnel say 2-3ft in depth will that suffice without having to dig new drain trenches, will I get away with the raised beds or am I just asking for trouble further down the line? Will the beds eventually sink into the sodden ground? Help!! Thanks chris.

Thank you for the reply,