In practical terms, what this means is that truly unrunnable rapids
wil develop, which further implies either 1) human intervention to
open them up (explosives), or 2) the river will be closed to all
boats that can't be portaged. Number 1) is at this point unlikely,
of course, but we are talking fairly long timescales -- it's hard to
make meaningful predictions about human values 100 years from now.
Of course, the dam may not last that long, either -- they almost lost
it once...
It does seem unlikely that a flood could create a rapid that could
not be run and could not be portaged, at least at some water level.
Thus, the net effect of this evolution is to restrict trips to small
boats.
-- Kent Crispin "No reason to get excited", kent@songbird.com the thief he kindly spoke... PGP fingerprint: B1 8B 72 ED 55 21 5E 44 61 F4 58 0F 72 10 65 55 http://songbird.com/kent/pgp_key.html ==================================================================== To subscribe, send email to majordomo@songbird.com, with "subscribe gcboaters" as the only line in the message body. To unsubscribe send "unsubscribe gcboaters". For further information send "info gcboaters", or see http://www.songbird.com/gcboaters ====================================================================