Why Our Conservation Schedules Were Too Little &
Too Late
October 6, 2013
 |
| The parched earth after record 8 year droughtE |
Discounting Gov. Perry’s bizarre attitudes and
inaction with regard to the drought, our “pre determined trigger points” for different levels of
conservation were based on the worst drought on record in 1951. At that time Austin’s population was
132,000. The current population is
843,000, a 6.38 times increase. In addition, there were no water hungry industries, like the semiconductor chip fabs that inhabit Austin now. A study in
the late 2000’s revealed that an average chip fab plant used enough water to supply a
city of 50,000 people. Austin has 14 of
these plants, which consume even more water than the plant that was studied,
because the wafer size was 6”, and now the standard is 8”. The amount of water needed to rinse a wafer
increases exponentially, not linearly.
But for the purposes of this essay, I will use the 50,000 people per plant estimate, so the chip fabs add 14 x 50,000, or 700,000 people. That makes Austin functional population
around 1.5 million.
With lake reservoirs at about
the same level in 1951 as now, 600,000 acre/feet, with only 132,000 people, the
threat of running dry was distant.
People used less water then than now, but for simplicity, I will use the
current outrageous usage of 168 gallons/per person per day. So, the extra hypothetical extra 700,000 people use 168
gallons/per/capita/day = 700,000 x 0.325 = 227,000 acre-feet. (The conversion
from gallons to acre feet is 1.0 million acre-feet = 0.325 gallons.) Therefore, the total usage per day is the total of the actual number of people plus
that used by the additional usage by the hypothetical people represented by the
extra 227,000 acre-feet per day.
Another factor to be
considered is that the two reservoirs, are the only source of water for not
only Austin, but the additional people that have filled up Travis county as
suburbs that didn’t exist in 1950. The current
data indicates that there are 1.7 million people in the county. Almost as many people in the county outside
the Austin city limits, as there are in within the city. Therefore, the total number of people
dependent of the two reservoirs, is the previous calculation including the
hypothetical people, plus 1.7 million less 843,000, or 857,000 added to the 1.7
million = 2.58 million.
Today the 2.58 million times
the daily usage of 227,000 acre-feet per day of usage = 5.85 million acre
feet/day, divided by 30 days per month resulting in only 1.95 months
until we run dry.
Had the trigger point
estimates took into account the population increase we should have been at
level 3 conservation in 2009, and level 4 early in 2011. If those conservation measures were carried
out, we would not be in the critical state we face today. With only about 14
months if you believe the State web site which says that we have 600,000 acre
feet, and states that lake Travis is 30% full (which would be 260 feet of
water, when it has been a plainly visible empty pit for almost 2 years. So, with that bold face lie to foster
confidence that lake Buchanan has what the web site states, my guess (and it is
just a guess because the real data is no where to be found) that Buchanan has
only 50% of the stated value. That would
give Austin only 4 months until we run dry.
Keep in mind that the inflows for 2013 have been almost as low as 2013,
or about 30% of normal. That amount is
neutralized by loss to evaporation and the fact that 10% of the water at the
bottom is unusable because of sediment.
The forecasters including all of the meteorologists and climatologists
see no change in the near future (up to 5 years) so we are using up a fixed
amount of water.
Morris Creedon-McVean
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