Sunday, March 22, 2015

Drought in the Rattlesnake Hills - Revisited, Or California It's Not


What does the California Drought and the Yakima Valley drought have in common? Well, they are both on the west coast and if you are from 'back east' you know that states are only an hour apart. (Out west, counties are sometimes an hour apart usually more.) Beyond sharing the same coast, not much is the same regarding the two droughts.
First of all, California's drought is in its third year. The reservoirs are empty. Ground water is being tapped out. The Yakima Valley is coming off a huge water year. The reservoirs are overfull. In fact some are several feet over full.
If a reservoir is one foot over filled, how much can that help? If the lake is 1000 acres on the surface, one foot of extra water will provide a full water right of three acre feet for 333 acres. A little more storage at the top of a lake can go a long way.
The truth is the Rattlesnake Hills AVA is not experiencing a drought at all. In fact rainfall is very slightly above normal, but as stated earlier, rain on the desert is immaterial. A few hundredth of an inch on five and one half inches just doesn't register. I still have to water my cactus garden!
Green grass between the rows
The Cascades which provide water for the Yakima Basin are somewhat short on precipitation, but nothing like California. In fact the Drought Severity Index published by NOAA says that our precipitation is near normal. SE Washington, including Walla Walla, is having a moist spell.
So why did Governor Jay declare a drought emergency? Maybe because he used to live in Selah or he just likes being governor and making declarations. You get your picture on TV!
The real problem is not the lack of precipitation as in California, it is the lack of storage. Five reservoirs serve the Yakima Basin Project. Those reservoirs are full to the brim and overflowing. The problem lies with what we call the sixth reservoir - snowpack. Due to the mild winter, there is no snow in the Cascades! Normally the snowpack serves the irrigation needs into June at which time we start to tap the reservoirs. This year the reservoirs will be tapped early and tapped out by season's end.
Back to the drought in the Rattlesnake Hills AVA. The western and southern portions of the AVA are served by senior water rights. That means they get three acre feet of water or 100% before junior water rights get a drop. No drought there. Junior water rights like the Roza Irrigation District are scheduled to get 73% this year - not bad for vineyards which typically only need 50% of their allocation. North of the Roza ,the AVA gets its water from wells and unlike California, the wells are not going dry, yet.
With the drought declaration, I can tap into my emergency well which has more water than my Roza water right and water transfers are allowed.
I think the Rattlesnake Hills AVA will get along just fine this year so we can supply California with much-needed high-quality grapes.
Next year, as the skiers say, "THINK SNOW!'

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