Climate Change v. Imported Water

Much has been written about how dependent San Diego is on imported water.
Eighty percent of SD’s water is imported from Northern California and the
Colorado River. This fact gets a “So What” from most San Diego water users,
and more importantly from the San Diego County Water Authority (SDCWA) who,
in their Master Plan, show six percent recycled water by 2020. There are so
many disaster scenarios hitting the media daily residents are appear to be
less concerned about where our water comes from than climate change. Not a
day goes by that some entity forecasts how we are going to be enveloped in
rising sea levels and temperatures rising by a degree or so a couple of
hundred years from now. So does climate change have the highest priority?
Todd Gloria, who served seven months as interim mayor, seems to think so,
with his initiative to push climate change solutions for the City of San
Diego.

Let’s take a look at the imported water challenges facing San Diego.
Of the eighty percent of water coming into San Diego County, about a quarter
of that amount is from the State Water Project via the Metropolitan Water
District (MWD). The rest is from the Colorado River via MWD. Due to the
drought, San Diego is already threatened to lose the State Water Project
water, so okay “not a problem” the SDCWA says. “We have plenty of storage to
last us through 2014 since we upgraded our storage capacity”. But what about
the Colorado River?

A common misconception is that water coming from high in the Rocky Mountains
of Wyoming and Colorado is pure and sparkling. Sure, it starts that way from
snow melt, but by the time it gets to the Lower Colorado River it is as the
old timers said, “Too thin to plow and too thick to drink”. It carries a
silt load several times higher than other rivers of equivalent size. Where
does the silt wind up? Behind the recently built dams along the river, and
most spectacularly, Glen Canyon Dam.

James Powell, in Calamity on the Colorado, the author of “Dead Pool”, wrote in Orion Magazine in 2010:
“Asked in 1955 what the Bureau of Reclamation plans to do when sediment
threatens to fill Lake Powell, the 186-mile-long reservoir on the Colorado
River, former reclamation commissioner Floyd Dominy replied, “We will let
people in the future worry about it.” Lake Powell [named for John Wesley
Powell] and Glen Canyon Dam are less than 50 years old, yet already we can
see that those who will bear their true costs will not be some generation in
a distant future, but our children and grandchildren, and even ourselves.”

Powell goes on to say: “With demand rising and supply falling, Lake Powell
could reach dead pool in the 2020s. Impossible? Hardly. Between 1999 and
2005, the reservoir lost two-thirds of its volume and neared the elevation
of its generator intakes, 333 feet above the riverbed. Another two or three
years at the same rate of decline and Lake Powell would already be at dead
pool. Fortunately, a wet 2005 intervened to offer a temporary reprieve.”

In Water Shock, principal character Charlie Reagan is talking about how we
could learn from beavers. “As natural hydrologists and hydraulic engineers,
they have an innate sense of where to build dams on a lively mountain creek
and when to tear them down when they fill with silt. Using their sharp
teeth, they cut the quaking aspen and lodgepole pine of various sizes to
build the base structure, and then interlace the structure with willows,
packing the spaces between with mud carried on their flat tails to the
proper place, leaving enough space for the stream to find its way out of the
bottom of the dam.

“During the spring runoff, when the water is brown with upstream soil, the
dams accumulate silt. At the proper time, perhaps after two or three
seasons, the beavers tear down the dam, allowing a gentle distribution of
the silt along the creek bottom when the level of the creek subsides. This
makes them, in addition to all of the above abilities, the first soil
conservation engineers.”

But as a society we unfortunately have not learned what the beavers know. We
cannot build dams with no method to drain them to move the silt downstream
in a regulated fashion. We have constructed a living nightmare along the
Colorado that threatens to destroy the lives of tens of millions of people
in the Southwestern US, and on one appears to be paying attention.

My father, a researcher for the State of Montana Highway Department often
said, “I shall always be amazed at the infinite capacity of the human mind
to resist the penetration of useful knowledge.”

What is most important to San Diegans? Likely loss of the Colorado River
Water based on actual verified field data within a generation, or some
future change in the climate hundreds of years from now based on computer
models?

Milt Burgess