I've done the lower stretch as low as 500-600, after a rain in October. It's creeky and fairly fun, but there's no way that makes it worth putting in on the upper section, which is your only option until the gate is unlocked. If there was any water to launch at the put-in (doubtful), you would quickly find yourself hiking your boat in what would amount to a VERY long day. Possibly a multi-day survival hike, in fact.
Give it a few more weeks.