Trouble Right Here in River City

 

The flood that raged down the Colorado last month was a startling reminder that the river isn’t just a nice recreational centerpiece for Austin. It is the defining geographical feature of the entire Central Texas region. And disastrous flooding isn’t just part of history. It’s the risk we take every day for the privilege of living in this location.

I got interested in the Austin Dam Disaster of 1900 a few years back because I saw the parallels with the Austin I had grown up with and resided in today. It’s one of the great themes of Austin’s existence to be a city on the move and on the make. But occasionally, Mother Nature administers a dose of humbling reality. Watching these events unfold over the last couple of weeks was like watching the 1900 flood come to life—fortunately, the consequences this time were far less permanent.

Austin was chosen as the capital of Texas in part because of the potential water power of the Colorado. But for the first century of the city’s history, the river was more of a foe than a friend. It may come as news to Austin’s many newcomers, but Central Texas happens to be the most flood-prone region of the entire United States.

The reason? Austin sits at the intersection of the Gulf, Pacific, and Plains weather systems—a recipe for rain events of incredible magnitude. Pair that with hilly geography, thin soil, and shallow creeks and rivers. Well into the 1930s, Central Texas was subjected to devastating flooding on a regular basis. And as we saw last week, even the full capacity of the six dams and lakes operated by the Lower Colorado River Authority can only mitigate a major flood event, not prevent it altogether.

View this post on Instagram

A rare view.

A post shared by LCRA (@lowercoloradoriverauthority) on

As in 1900, the 2018 flood began with an unusual series of rain storms that soaked Central Texas with the wettest September on record. On October 8, a rain bomb over the small Hill Country town of Junction dumped 12 inches into the Llano River in just a few hours, rampaging through an RV park and sweeping four people to their deaths. It was the LCRA’s job to move this water carefully through Wirtz and Starcke dams and into Lake Travis, which was specifically built to protect the city of Austin from flooding.

A week later, a weekend of heavy storms climaxed with a strong cold front. This time, the Llano came out of its banks even more disastrously. Most dramatically, the FM 2900 bridge at Kingsland was carried away by the force of the waters, and Kingsland, Granite Shoals, Marble Falls, and other lakeside communities endured major flooding. For the first time in history, all six of the Highland Lakes dam were open in a remarkably orchestrated ballet of floodgate operations. Lake Travis reached an astonishing 143% of capacity—the fifth highest on record.

Several people have asked me if the dams were ever in any danger of failing, as the “Great Granite Dam” did in 1900. Fortunately, the answer is no, that is not a realistic fear. The river is far better understood than it was in the 1890s, and the Highland Lakes dams are infinitely better designed and constructed. The LCRA performs frequent upgrades on the dams to keep them current—in fact, the river authority began work in August to replace the floodgates on Tom Miller dam at Lake Austin, one of the most extensive modernizations the dam has ever received. I believe the success of the Highland Lakes system is the most significant (and under appreciated) component in the exponential growth of Austin over the last 70 years.

The fallout for the city of Austin in 2018 was far short of the death and destruction wrought by the 1900 disaster. However, the city did not escape unscathed. On Monday, October 22, the unprecedented amount of silt contaminating the city’s drinking water supply caused Austin Water to issue a citywide boil water notice that remained in place for an entire week. For a short time, it was feared that the city’s water pressure might drop below the level necessary to supply the fire hydrants. Our 1900 counterparts didn’t have it so easy. Back then, residents digging out from the dam disaster had to haul water, and it was nine months before any basic utility service returned to the city.

Want to know more? Check out my book The Austin Dam Disaster of 1900, available on Amazon or at your favorite Austin bookstore. It also makes a great gift for the Austin history lover or the engineer in your life.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: