Why Austin Doesn't Need a New Water Treatment Plant on Lake Travis

The Austin Water Utility is asking the Austin City Council to fund construction of a new $423 million water treatment plant on Lake Travis, known as Water Treatment Plant 4. (Austin had three treatment plants but decommissioned the Green plant on Lady Bird Lake just last year, but the name remains for this enormously expensive, and entirely unnecessary infrastructure.)

The price tag for this new treatment facility is huge, and the utility is asking for over $110 million in this year's budget to get started on construction. They are proposing to raise water rates across the board for the next five years to pay this enormous expense.

When our local City Council Members are considering authorizing a project that will cost almost half a BILLION dollars, shouldn't the first requirement be that we need the thing? Because if we don't need it, aren't there better things to do with Austin ratepayers' money? If we must give millions to construction and engineering firms, can't we better use their talents to fix leaky pipes, install infrastructure for reclaimed water, and design water efficient buildings and landscapes?

So do we need an additional 50 million gallons a day of water? The utility claims that we must have Water Treatment Plant 4 up and running by 2014. According to their presentation to the Water and Wastewater Commission on July 8th, "This project is on an aggressive schedule to provide water by 2014 and avoid any shortage in capacity."

Austin's current capacity is 285 million gallons per day, with the Ulrich plant capable of treating 167 million gallons per day (MGD) and the Davis plant at 118 MGD. Both of these plants are on Lake Austin, downstream of Lake Travis, on the Colorado River.

A consultant to the utility recommended a 10% buffer below the system's capacity as a threshold at which more water would be "needed." That comes out to about 260 MGD.

Summer months are when water use increases greatly, mostly for lawn watering. The days when we use the most water are called "peak days." These "peaks" determine when we bump up against the 10% buffer, and again, lawn watering is the primary driver of peak day water use, up to 50% of all water used on peak days.

The pertinent question for City Council becomes "When will we reach 260 million gallons a day of water use?" While the utility claims that Water Treatment Plant 4 must be functional by 2014, their own projections show that we don't reach 260 MGD until 2019. And that's assuming that each summer we use more water on the hottest days than we did the year before. And that's ignoring the fact that last summer we used 20 MGD less than previous summer peak days where they began their projection. For the chart showing projected "peak day" water demand, go to http://www.sosalliance.org/library/Peak-Day%20Demand%20Projections%20Gra...

The utility's projections for "peak day" demand in 2014 are around 250 million gallons per day (see yellow line in chart, which represents projected use under the Council mandated "1% savings").

Now, if it will take five years to build the treatment plant, and we aren't projected - using very conservative estimates of water conservation - to "need" 260 million gallons a day until 2019, we don't "need" to start building the plant until . . . 2014, the very year the utility claims that the plant must become operational!

2008 was a brutally hot summer, which is when you would expect high peak day water use from lots of lawn watering. But last summer the peak went down, from all time highs of around 240 MGD to about 220 MGD. This is likely because of the switch to a simpler two-day watering schedule and some promotional effort on water conservation.

2009 so far has been hotter and drier than 2008, and peak day water use has only hit 220 MGD, even though the water conservation promotional efforts have become much less visible (anyone heard the Ray Benson jingle lately?).

If you take at face value the utility's assumption that every summer we'll use more water than we did the summer before, that we can't improve and get our peak use below 220 MGD, and begin the trend line (blue line on the chart) at 220 MGD, you don't get to 260 MGD until 2024, literally off of the chart.

So back to the first question - do we need a new water treatment plant? Not any time soon. According to the water utility, we have to have Water Treatment Plant 4 open by 2014 to "avoid any shortage in capacity." But their own data show otherwise, that we don't "need" to start building the plant until 2014.

But let's say that in some strange alignment of malign neglect by the utility and city-wide attachment to excessive lawn watering we get to 260 MGD in 2014. What happens?

We cut lawn watering to one day a week. San Antonio just did this and lowered their June water use by 23% compared to last June. 23%! But we probably don't need to do that if we get smart about water conservation.

Is it worth $423 million and higher water rates to ensure extra lawn watering during hot summer months?

If we invest a small fraction of the cost of Water Treatment Plant 4 into more aggressive and intelligent water conservation, we can keep our peak day summer water use flat for years to come, just as other cities have done, like San Antonio and Los Angeles. We might not ever need a new water treatment plant, and if we ever do, we can build one for much cheaper on Lady Bird Lake than Lake Travis. We need a Pecan Street Project for water conservation, not a boondoggle waste of ratepayer money.

When was the last time you heard the Ray Benson water conservation jingle?

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