News about the Lookout at Brushy Creek, a custom home community just outside Hutto, Texas.

Wednesday, July 29, 2009

No leak in the dam

There is no leak responsible for the drop in lake levels. Just evaporation
and lack of rain.

In fact, even the normal seepage you'd expect from an earthen dam has now
dried up. In May we had the same professional engineer that did the
original report in 2005 just come out to review and update that report, and
he found no evidence of leakage either.

We have only had 25% of our average rainfall so far this year. Coupled
with 40+ days of over 100° temperatures and the evaporation is far above
normal. You may have heard that Lake Travis is down 28 FEET from normal
July levels, and the last boat ramp will probably soon be closed as it is
supposed to be shut down at 640 feet, and the lake is currently at 637! We
are in a drought of a severity that hasn't been seen since the 50's, and we
may come close to the 1903 number! A true hundred year drought.

The LCRA says that Lake Travis is currently losing about two inches a week
due to evaporation, and that is a much colder and deeper body of water. Our
lake will evaporate faster and faster as it's average temperature rises.
Many of the small tanks and ponds in the neighborhood have been dry since
the early part of the year. If the 100° days and no rain continues, the
large lake may well follow them.

As far as recovering the lake level, I'd say we will operate on the same
plan that the LCRA is using to recover the highland lakes. We need rain,
lots of rain.

A leak is not the issue with our dam.

Now, what work the dam does need in order to meet Texas Commission of
Environmental Quality guidelines is more spillway, ironically enough. Far
from a leak, the problem is we don¹t have enough spillway area to safely
pass floodwaters without failing ­ and the plan and costs to get in
compliance will be a major topic of discussion at the annual meeting. The
hydrological engineer who has done all of the research on our dam will be
there as well, so I'd encourage you to attend. He will also be the project
manager if we decide to fund the repairs, so he should be able to provide as
detailed an answer as is currently possible to your questions.

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