Clean Valley air road long and circuitous, important achievements made, much work ahead still

The Fresno Bee on Dec. 16, 2007 introduced its groundbreaking Special Report Fighting For Air. This source was referenced here before.

Its mention is important from the standpoint that at that time air quality in California’s Central Valley was a big deal. And just how big a deal was it? Between 2004 and 2007, according to information presented by one of Fighting For Air’s several contributing reporters, air pollution was the top worry.1

And, for good reason: Annual healthcare costs related to the inhalation of Valley air was an estimated $3.3 billion2, there were four premature deaths daily attributed to the effects of dirty air3, and better than 20 percent of Valley children were asthmatics.4

So, what has changed health-statistics-wise, air-quality-improvement-wise and maybe, policy-wise at the local, state and federal levels, in the one-dozen-plus years since the report’s publication?

Around the time the National Ambient Air Quality Standards (aka NAAQS) for coarse particulate matter (PM 10 or particulate matter 10 micrometers thick or less in size) in the San Joaquin Valley had just then been met. Subsequent to this and according to the San Joaquin Valley Air Pollution Control District, another milestone was achieved: the NAAQS for 1-hour ozone. This notwithstanding, there remains much air-cleanup work left to be done.

The region has seen further improvement, but it’s been limited. Playing into that no doubt is farmable acreage and loss in open-lands space, plus increased population, driving and metropolitan sprawl that accompany residential and/or commercial and/or industrial expansion.

The San Joaquin Valley has until year 2023 to meet the oldest and as-of-yet-unmet 8-hour NAAQS for ozone of 84 parts per billion (ppb) which, it would appear, the Valley is on track to meet. The mandated deadline to meet the most recent 8-hour ozone health standard of 70 ppb and set Oct. 1, 2015 is 2037. It is progress nonetheless.

Even so, it is clear with regard to ozone, more air-cleaning is necessary.

That’s just for ozone. The Valley must as well meet stringent federal fine particulate matter standards: 35 micrograms per cubic meter (ug/m3) for fine PM (PM 2.5 or particulate matter less than 2.5 micrometers in size) measured over 24 hours and annual PM 2.5 set at 12 ug/m3 the latter set by the U.S. Environmental Protection Agency on Dec. 14, 2012, neither of which have, so far, been met.

Valley air highlights

The Report to the Community 2019-20 from the San Joaquin Valley Air Pollution Control District was just recently published. Valley air overall or generally speaking, is cleaner. In fact, last year was the cleanest recorded since record keeping began, for not just one Valley air pollutant, but two: ozone and fine PM. Now add to this that significant reductions in tons per day were made with respect to oxides of nitrogen (NOx) 18.7 t/d; sulfur oxides (SOx) 4.85 t/d; and volatile organic compounds (VOC) 47.32 t/d, exceeding the targets. Likewise, at a 14.95 t/d reduction in PM equivalency terms, was fine PM.5

But, perhaps most encouraging was news that in 2019, the number of unhealthy air quality index days for ozone reached an all-time low (what looks to be very near zero).6


  1. Mark Grossi, “Stiffer rules could speed cleanup,” Fighting For Air, special installment, The Fresno Bee, Dec. 16, 2007, p. 2
  2. Ibid, p. 6
  3. Ibid, p. 1
  4. Susan Anderson, “Fresno is state’s asthma capital,” Fighting For Air, special installment, The Fresno Bee, Dec. 16, 2007, p. 5
  5. Report to the Community 2019-20, “Working With the Public on Air Quality Strategies,” p. 6
  6. Ibid, “Summer Ozone Season Best on Record,” p. 8
California’s expansive and agriculturally fertile yet often air-polluted San Joaquin Valley

This post was last revised on Jul. 20, 2020 @ 9:35 a.m. Pacific Daylight Time.

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