David E. Ross wrote:
songbird wrote:

thanks to a huge amount of new rainfall in the
upper Colorado River Basin and recent rains in
southern California (Delores) you folks are
getting a little more breathing room.

i hope you use it wisely...

Yesterday's rains (1.26 inches near my house) will do little to refill
California's reservoirs. The primary source of water for the reservoirs
is precipitation in central and -- most important -- northern
California. Some cities in southern California -- including Los Angeles
-- do attempt to capture rainfall and use it to replenish underground
aquifers. And, of course, we all will be using less water for a while
to irrigate our gardens.

yes, however, my post was aiming more at the difference a
few million acre feet of water will make over the next few
years that as of a few months ago were not there. it was
looking like they may have had to declare a shortage for
Lake Mead water levels and that affects both Arizona and
southern California water supplies above and beyond what is
already lacking from the reserviors.


Where I live, we do not get any water from the Colorado River. A slight
increase in its flow from storms in the northern part of its watershed
will mean a slightly less demand for water from the California Water
Project's dams and aqueduct.

this is a more structural and legal and or treaty difference
than "slightly less demand" implies. however it is also
important in other ways as it impacts how much electricity can
be generated (they are currently upgrading the turbines at
Hoover Dam to be able to generate electricity efficiently at
lower water levels, but this is underway and not done yet).


Thus, we are getting some minor relief. At this stage of the drought,
even minor relief is welcome.

oh for sure, and any little bit that can go towards
groundwater recharge... however a large fraction is
likely to be lost due to evaporation, but that might
end up further to the east in the mountain ranges as
rain or fog/mist/dew. at this point any single drop
is better than none.


Today, I have not seen any rain. The weather is hot, cloudy, and
extremely humid. The 9:00am PDT forecast is for 50%-60% probability of
measurable rain this afternoon, this evening, and daytime Monday.
"50%-60% probability" means that 50%-60% of the area will experience
some rain, not that all areas have a 50%-60% probability of rain.

the radar is currently showing a nice pattern for the
area to get more actual rain on the ground, i hope the
rains can hold together long enough to actually get the
ground soaked in places enough to give the trees and
rivers a bit of a recharge.


As of 30 June, 12 major California reservoirs were collectively at 37%
of capacity. That is less than half the historical average for that date.

and as they get emptier the problems get tougher (water
quality gets poorer as they get warmer, with algae problems
and pumping and treatment costs rise, hydroelectric generation
reductions, etc.). also the losses in forest cover in the
north will make things even worse as you lose your sponge
and soaking zones, but you also lose your trace moisture
capture capabilities (forest can trap, condense and soak up
mists/fogs).


songbird