more than physics

People talk about water scarcity like it’s a physics problem: why don’t we tow icebergs from Alaska to alleviate the southwest’s water issues?  what about pumping water from the Great Lakes across the Rockies?  Sometimes that sort of grand thinking works, like the diversion of California’s water resources from the upper Sierra Nevada mountains southward to the Central Valley and Southern California.  But that’s only part of the equation.  One reason that California’s State Water Project and Central Valley Project are successful is that the source is virtually pristine snowmelt.  Move clean water from an area of relative abundance to an area of relative scarcity, add in a comment about humans adapting the environment to their needs, and voila, problem solved!

In my last post, I remarked on China’s limited water resources and their lack of wastewater treatment.  Well, not surprisingly, the Chinese government is trying their darndest to move water around to alleviate chronic water scarcity in the north (think Beijing) with relative abundant water from parts south (think the Yangtze River).  They’re apparently getting close on parts of this great diversion – the Danjiangkou Reservoir should be sending water northward next year.  The physics problem has been solved for a mere $81 billion!  Good job.

One small problem: the water to be transported is currently not fit for drinking.

A water pollution plan issued by the State Council, or China’s cabinet requires that the water quality for all five rivers that flow into the Danjiangkou meet a “grade III” standard by 2015.  But four of those rivers are now rated “grade V,” deemed for “agricultural use only” and the fifth river is considered “grade IV,” for “industrial use only,” reports China’s state-run news agency Xinhua.  “The target is very unlikely to be met as many pollution control projects lag behind schedule due to a fund shortage,” said Cheng Jiagang, vice mayor of Shiyan in Hubei province.

Oh.  What kind of fund shortage, when you just spent $81 billion on construction??

I’ve remarked previously on the lack of fame associated with building brand new shiny underground water infrastructure, and this appears to be a similar problem.  According to the above article, the local government needs about $500 million (just a fraction of that $81 billion price tag!) to build a wastewater treatment plant with nearly 700 miles of sewer pipelines.  So far, they’ve shuttered “329 factories in the last few years, but that has cut revenues by $130 million annually”.

Well, I hope they can find the money.  Until then…good luck to those intending to rely upon the diverted water.  Physics ain’t everything, folks.

why change now?

Merced, California is located in the dry but productive Central Valley of California.  Besides local groundwater, farmers in the Merced Irrigation District use the water stored in Lake McClure on the Merced River.  Looking to expand their water supplies, the Merced Irrigation District has proposed to raise the spillway as much as 10 feet in the reservoir, so that they can capture more runoff from the Sierra Nevada Mountains in particularly wet seasons.  It’s a relatively simple change from an infrastructure perspective, but there’s one catch: the expanded reservoir, when full, would flood part of the Merced River designated as a “Wild and Scenic” river.

The “wild and scenic” designation comes from a 1968 law to “protect wild rivers and scenic rivers from development that would substantially change their wild or scenic nature.”  Only 156 rivers across the US have wild and scenic status, and the goal is to preserve these rivers’ free-flowing condition.  Sounds like that’s not really compatible with an expansion of Lake McClure.  Nonetheless, the local congressman, Rep. Jeff Denham, has begun the process of removing the “wild and scenic” designation from this section of the Merced River, and the House has already approved the bill that includes this provision.

This is a clear case of the values of our ancestors (those 1960s environmentalist hippies) clashing with the priorities of today.  We’ve decided a certain way to balance ecosystems and free flowing rivers against our water demands, and have been using it for ~44 years, but now we’ve gotten tired of that approach?  Environmentalists are rightly fearful of the legal precedent that this revocation would set.  Why bother with such designations if we will later down the line decide that progress comes first?

It sounds to me like the Merced Irrigation District should consider alternative methods of water storage, at least to compare the relative costs.  For example, storing water underground during wet seasons could be just as viable (I’m pretty sure this part of the Central Valley has the right alluvial sedimentary geology for underground storage) with far fewer environmental costs.  No change to the “wild and scenic” status would be necessary if water management strategies from 2012 were used instead of those from the 1960s…

Kansas and Texas: the next Yemen

I wrote earlier about the groundwater overdraft in Yemen, which was largely due to irrigated farming (specifically for qat, a mild stimulant).  I sort of brushed off the idea that the Ogallala aquifer was drying up.  But, researchers recently used satellite data to show that yes, it is drying up, and at an alarming rate.  In the southern portions, the aquifer may be unable to support irrigation as soon as 30 years from now.  The northern portions seem to be holding steady in water level, due to rainfall and infiltration from lakes, so only Kansas and Texas would be affected.  The same study showed that groundwater tables fluctuate widely in California’s Central Valley, although a clear decline is not evident.  These are major farm belts in the US, and the loss of irrigation water would be, quite simply, devastating for those areas.  We would do well to take heed and adopt proper policy measures to sustain these critical but not unlimited water resources.

How not to conduct a public workshop

As I mentioned the other day, there is a lot of frustration and denial on the part of farmers when it comes to nitrate pollution in the Central Valley.  Recently, the UC Davis researchers who wrote the massive report on nitrates in groundwater held a public workshop to formally present their results.  When pressed on the 96% figure for nitrate coming from agricultural sources, one of the scientists acknowledged that the figure may not be “precise”.  Oh dear, you just admitted uncertainty – surely it only went downhill from there.  Where were the error bars in the original study?  If you admit uncertainty, then error bars at least constrain the uncertainty.  An admission of imprecision suggests to the public that it all might be crap.

Turns out that the farmers may have some reasonable issues with the study methodology, partly because the study had to estimate nitrogen fertilizer application rates over the past ~60 years.  Nitrogen prices have gone up significantly, which already presses farmers to be highly efficient in their applications.  Plus there is more and more use of low-water irrigation (e.g., drip irrigation), which further decreases the rate of nitrogen leaching into the groundwater.  The scale of the UC Davis study simply did not permit inclusion of these trends, which suggest that farmers are already mitigating the nitrogen issue as much as they can.  Based on the above article, I doubt that the researchers satisfactorily explained why they conducted the study in the way that they did.

That said, legacy contamination is still an issue, and I don’t think there’s any way that fertilizer application was not the cause of the groundwater nitrate contamination.  So who should pay to clean it up?  I would still argue that nitrogen fertilizers and irrigation water are the easiest things to target, even if it is a burden on the farmers.  The fees would provide a cost-benefit incentive for all farmers to engage low-water irrigation and efficient nitrogen use, plus there is some talk of using contaminated groundwater as irrigation water, letting the nitrates be consumed by crops.  Think that’s unfair, farmers?  Talk to the chemical industry about joint and several liability for Superfund sites under CERCLA…

recycling isn’t everything

I thought I should post this, after my enthusiasm for recycling in my last post: sometimes turning a waste stream into a marketable resource is a bad idea.  In fact, sometimes it’s a disaster.  Turns out, chemical companies thought about this a lot over the years, especially in the pre-regulation days.  In the 1940s and 1950s, Dow Chemical and Shell produced plastics from allyl chloride, and one of the by-products was a chemical called 1,2,3-trichloropropane (TCP).  Side research suggested that this compound could be added to a popular fumigant (Shell’s was called D-D, Dow’s was called Telone) without ill effects.  A Shell memo from 1981 suggests that the company made $6.3 million in fumigant sales, and saved $3.2 million in disposal costs for TCP.  In effect, the companies were able to use this waste as “filler” in a marketable good — perfect!

Originally the companies claimed that TCP was effective at killing nematodes, but subsequent research was unable to prove these claims.  In the meantime, the fumigants were used extensively in California’s Central Valley, where the compounds most resistant to degradation entered the groundwater, and the EPA, Clean Water Act, Safe Drinking Water Act, and Superfund law all came into effect.  Furthermore, we know today that TCP is a carcinogen, and more than 200 water wells across the Central Valley have elevated levels of TCP.  Although Shell stopped selling D-D in the 1980s and Dow changed its Telone formula in the 1990s, TCP will persist in affected groundwater for years.  This means that there are quite a few lawsuits out there to force these two companies to pay for additional treatment for existing water supplies and for external water supplies where treatment is unavailable.   The companies already settled with one small municipality for $13 million, which suggests that there are a few more settlements headed their way…

So to be clear, recycling works when you’re not dealing with hazardous material that may become a human health risk in the future.  It does not work when you try to hide toxic materials in useful products.