Water Woes

I spent quite a lot of time in both California and Florida this past year. Along with plenty of sun, beaches, and news of the weird, both have issues with supplying enough drinking water to their growing populations. Florida, Georgia, and Alabama are fighting each other (link from WashingtonPost) over surface water. Within Florida, there is talk of shipping water from the St. John’s River south to central Florida. Lake Lanier in Georgia dropped to such low levels last fall that Atlanta had less than 90 days of water supply – with no plan for action if there was no relief. Georgia is trying to take water from the Tennessee River, claiming that the true northern boundary of the state includes part of the river. Western states are continuously squabbling over water rights. Those problems might be minor in comparison to the issues that will face China and India in the near future.

China – Thirsty Dragon

China has been drawing heavily out of the system of aquifers underlying the North China Plain for some time (see link from 2001). This region includes Beijing, and the aquifer provides water for a sizeable fraction of China’s wheat and corn crops.

Recently projects to divert water from the south of the country to the north have been undertaken (2006 story). It doesn’t sound like they will be ready for many years, however(NYT):

“In the past, the Communist Party has reflexively turned to engineering projects to address water problems, and now it is reaching back to one of Mao’s unrealized plans: the $62 billion South-to-North Water Transfer Project to funnel more than 12 trillion gallons northward every year along three routes from the Yangtze River basin, where water is more abundant. The project, if fully built, would be completed in 2050. The eastern and central lines are already under construction; the western line, the most disputed because of environmental concerns, remains in the planning stages.”

The article has a comment that the aquifer under the North China Plain could be completely dry in 30 years. So it appears a very high-stakes race is on. Adding to the uncertainty is that demand in both the north and the south is going up. Existing water quality is also becoming worse, so diversion of clean(ish) water north will exacerbate pollution problems in the south.

Part of the high rate of usage in the north is agriculture, and in particular, winter wheat. Observers have proposed dropping this crop to reduce water demand, but the local population of farmers might not be able to afford going without the income that crop provides. I have seen a comment that it takes 1000 tons of water to produce 1 ton of grain. If so, importing grain really is the best way to import water. But this would certainly drive up worldwide grain prices. And then the farmers in the north would want to plant more to take advantage of the higher prices.

I have also seen a comment that water used for industry has a return 70 times greater than water used for agriculture. Therefore, it seems likely that most of the water delivered to the north will end up being used for industry. Eventually, China will have to import more grain, and this will drive up worldwide grain prices. The rising prices of grain in 2007 have already put untold millions at risk of hunger. Additional upward pressure on prices will push more and more people (including many millions in China) into threat of hunger.

Can recycling treated water help slow the need? There is some research into treating sewage to potable quality, called “toilet-to-tap” by some. The scale in China is pitifully small though: only 400L/day in the project described in this link (from Treehugger).

No word on if this will eventually find common usage feeding the tap, or if it will be injected back into the aquifer. Orange County, CA, has a 70 million gal/day plant that began operating in November (NYT). The treated water is being injected back into the aquifer to prevent salt water intrusion rather than going directly to the tap. China needs to be thinking on this scale, and rapidly.

India – Tainted Tiger

India faces tough choices as well. Here is a New York Times story (from 2006) about how polluted the Yamuna river becomes while passing through New Delhi. It sounds very severe:
“Coursing through the capital, the river becomes a noxious black thread. Clumps of raw sewage float on top. Methane gas gurgles on the surface.”
The river is the primary source of drinking water for the city.

I plan to post more on water needs in India soon.