Drift dive in a river...

[Avonthediver]

If you are worried about seperation and want to plan a controlled dive try placing an anchor from shore ta shore and test the water your in. and all of the above is very, very good advice!
diving a river can be trying and dangerous.

 

[irishsquid]

Here's a link to some excellent info, tips, and recommendations for river diving.
Check the different imbedded links for equipment, reading rivers, etc.
River Diving Technique

 

[Atom]

Had written a long reply....and lost it in a freak browser accident....

So to make it short, thanks to all for the tips/recommendations these were excellent and thoughtful answers, I'll definitely take these into account and update our current plan.