Posted: Mon, 5 Apr 2010 09:18 PM - 9,696 Readers
By: John Williams
Two significant anniversaries for Austin occur this month: Tom Miller Dam, located between Lake Austin and Lady Bird Lake, turns 70 years old Tuesday.
Tom Miller sits atop two predecessor dams that were both destroyed by catastrophic floods. The original Austin Dam was destroyed on April 7, 1900.
You can still see rubble from the dam in the lakebed of Lady Bird Lake. The rubble is a reminder of one of Austin's early glory periods, one that began with a campaign in 1889 to build the dam to revitalize the city.
Proponents claimed the dam would attract new industry by offering hydroelectric power. Even better, the city could break free of the utility that was charging, by the Austin American-Statesman's estimate, roughly five times the cost of delivering water and power.
Residents elected as mayor the pro-dam candidate, John McDonald. The following year, the city sold $1.4 million in bonds for the project.
The Austin Dam was completed in 1893 and the powerhouse two years later. It was the first dam built across the Colorado River and — according to the press hype of the day — the largest dam in the world.
By today's standards, the dam was unremarkable — a wall of granite and limestone, 65 feet high and 1,100 feet long. But Scientific American magazine was sufficiently impressed to feature the dam on its cover.
The city wasted no time in using its new source of electricity. It installed 31 moonlight towers — 165-foot structures that manufacturers promised would keep the community of 20,000 bathed in light throughout the night.
(The moonlight towers may have been Austin's first environmental controversy. Residential gardeners feared the "eternal moonlight" from the towers would cause corn and bean stalks to grow round the clock, so tall that gardeners would have to saw the plants down.)
The city built a rail line, with electric trolley cars, to transport residents to the dam and its reservoir, which was named for the mayor.
Lake McDonald became a popular attraction. Steamboats like the Ben Hur, a three-story sidew-heeler, provided cruises along with dinner, dancing and vaudeville shows. Watercraft enthusiasts canoed, sculled and sailed. Other attractions included a giant diving tower and a grandstand and pavilion for musical performances.
But the Austin Dam was doomed to fail — though no one realized it at the time. The dam was built on a fault line that allowed water to seep. Silt had filled nearly half the lake by February 1900. And there was no upstream structure like today's Mansfield Dam to capture runoff from heavy Hill Country rains.
So the dam lay unprotected when a five-inch rain fell in the Austin area on April 6, 1900, along with heavy rains in the Hill Country. The runoff created a flood wave, which one eyewitness estimated at 25 feet high and a mile wide.
At 11:20 a.m. on April 7, the floodwaters crested at 11 feet atop the dam before it disintegrated, with two 250-foot sections — almost half the dam — breaking away. The flood also damaged the powerhouse, drowning five workers, and destroyed the Ben Hur.
Eighteen people drowned in the flood, and 100 houses in Austin were destroyed, at an estimated loss of $1.4 million in 1900 dollars.
The destruction saddled Austin with heavy debt, and the city curtailed its public services. By 1905, according to the Handbook of Texas, Austin had few sanitation sewers, virtually no public parks or playgrounds and only one paved street.
In 1912, the city began rebuilding the dam, but another massive flood in 1915 severely damaged it. The dam went unrepaired until 1937, when Mayor Tom Miller reached an agreement with the Lower Colorado River Authority — which had opened for business in 1935 — to rebuild the structure. At the time, the LCRA also was building Mansfield Dam, which would eventually protect Austin from the worst of the river's floods.
Austin and LCRA dedicated the new Austin dam on April 6, 1940. Chamber of Commerce officials recommended naming the dam in honor of Miller, and the name stuck.
Seventy years later, Tom Miller Dam is still around — as is the LCRA, which is observing its 75th anniversary. The LCRA is proud to have partnered with Austin in this long-standing achievement.
The dam is a testament to the farsightedness of city leaders and to the LCRA's work in developing regional solutions, including the Highland Lakes and dams, which help meet local needs for energy, water and community services.
