Going Backwards: DFW’s Annual Smog Average Went Up Twice in Two Days Last Week

Denton Raises DVState officials and industry PR types thought they'd caught a break last summer when two things produced a much lower annual smog average, called a "Design Value." 

Since it's a three-year rolling average of smog numbers, past years roll off as new ones come on. Smog numbers from 2011 that had been so high they'd sent the average soaring, were finally rolling off and wouldn't be included in the average.

Second, unusually cooler temperatures and rain kept a new round of numbers lower. Combined, these factors resulted in a significant decrease in the smog average for 2014.

But in 2015, a more typical summer, or at least August, is bringing the average back up (Over 60% of the 100 highest recorded levels of smog this summer occurred in the last 30 days). Smog levels are higher across the board this year than last. There are more monitors recording more "exceedences" of the national smog standard. Leading them all is the Denton monitor, which saw ozone levels rise on Thursday and then skyrocket on Friday. The numbers were so high on both days they moved the needle of the annual smog average, the DFW Design Value, up from 81 to 82 parts per billion (ppb) on Thursday and up to 83 ppb on Friday. The standard is 75 ppb.

Even though Houston has recorded higher smog numbers than DFW this year, 2014's lower smog numbers was even more anomalous for that city than for North Texas. Last year's much lower numbers in the Bayou City are canceling out this year's much higher numbers.  So that in 2015, DFW's Denton monitor's annual average of 83 ppb is the highest in the State of Texas.

And that means that according to the official accounting of the Clean Air Act, DFW has dirtier air than Houston. And not for the first time.

It also means we're rolling backwards in terms of air quality progress. With at least a whole month of "ozone season" to go, DFW's smog average is now only a little lower than it was in 2009. It would only take one or two more bad days to raise the average again.

This is the second time in four years that DFW's smog average has increased during the implementation of a state clean air plan for the area. Neither plan required new controls on large industrial polluters significantly contributing to the problem, like the gas industry, East Texas coal plants, and Midlothian cement kilns. There may be some connection there.

Given the state's stellar two decade-old track record of never meeting a clean air plan deadline, its latest plan was always likely to fail. But a federal court roll back of the deadline to get to the 75 ppb standard at all DFW monitors, from 2018 to 2017, plus these new 2015 smog numbers, make it DOA in the real world. 

However, in the regulatory world governing these things officially, the plan is still being reviewed by the EPA and, believe it or not, could get approved if citizens don't make a big stink.

That's why you need to sign our Change.org petition to EPA to reject the state's plan and send an email to EPA officials requesting they write a new clean air plan instead of the state of Texas.

Many clean air advocates cautioned that 2014 should be seen as a outlier, and this summer is justifying that caution. If the experts are right, climate change will mean future summers will be more like 2011 than 2014. We've got to have a more realistic approach to the goal of safe and legal air. The State of Texas will not provide that. EPA can.

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