Thanks. You are correct about warm spring rains on snow producing floods. With irrigation directly from streams, mid summer flow is dependent on contributions from above around 5000 ft, depending on latitude, if I recall correctly. Irrigation from reservoirs can fill and capture some of the flow, but it is much better to "store" that water on the ground, rather than having to pass it through the system.

I've also heard that both less snowpack accumulation overall and earlier melt from higher than normal temperatures (before irrigation season) are also other aspects to this problem;
http://www.news.cornell.edu/releases/Jan97/water.hrs.html
http://www.usatoday.com/weather/climate/globalwarming/2008-02-01-water-c...
http://ccc.atmos.colostate.edu/newsapr1.php

The essay models above predict precipitation, they don't specify form. I don't think we'll see near the pack in the future either.

We've been very fortunate this year, after years of precipitation deficits, to get the snow we have. For lower elevations, the form difference has been often just a few degrees. The storms come in from the Pacific, moist and relatively warm.