It appears that you have severed your cam column. My guess is that the other side is not far behind. Is this a 2006 early model Adventure?
Since you're a strong pedaler, your best option is to take pics, see your local dealer and file a claim with Hobie. Although they will not give you a new boat, they may offer you one for a greatly discounted price. The new hulls (since 2009) use a much better "Click N Go" system that secures the drive -- easier to use and more durable.
If this doesn't work for you, you can fix it if you can get that cam column back in its regular place long enough to epoxy it. Here are some references below to get you started. Good luck!
Also with water in the hull -- do a leak test (check the FAQ or search).
The cam column is repairable and you can probably stabilize the other crack as well. In this high stress area I've found only two epoxies that work -- 3M ScotchWeld DP 8010 (and its variant 8010 NS) and Loctite 3030.
I like Bob's suggestion of making a repair sandwich of PVC halves, filled with epoxy to quickly and neatly apply the mix, as time is of the essence! -- haven't tried it though persoanlly. All your repairs will be inside the hull where you may not be able to see and work at the same time, so good planning cannot be over emphasized and working with sequential small batches prevents premature set-up. Don't skimp on the material -- it has to absorb the structural stress load where the PE failed. It's also a good idea to so both sides -- if one side is cracked, the other is probably not far behind.
Take a look at these notes from past repairs and don't hesitate to ask if you have any questions:viewtopic.php?f=71&t=33359&p=134475&hilit=#p134475viewtopic.php?f=71&t=33359&p=134482&hilit=#p134482viewtopic.php?f=11&t=11245&p=59882&hilit=d#p59882