water

There is water flowing under rock

    -Talking heads

Cool clear water

    -Hank Williams

Greetings

   Well the big news is that Gov Brown of California has imposed water saving measures on some California users.   (It's probably worth noting that although 80% of California's water use is for agriculture, but Gov Brown's  measures don't address agricultural use, so its unlikely to have   a big impact  see e.g.  How Ag Gamed Cal's drought)

        Here are some charts which show how bad it is there.  The situation is pretty severe .  Here's what the senior water specialist at NASA, and professor at Caltech said:

"Right now the state has only about one year of water supply left in its reservoirs, and our strategic backup supply, groundwater, is rapidly disappearing. California has no contingency plan for a persistent drought like this one (let alone a 20-plus-year mega-drought), except, apparently, staying in emergency mode and praying for rain."

   California agriculture provides a lot of stuff on our supermarket shelves such as over 90% of almonds, walnuts, broccoli, tomatoes, and strawberries.  Groundwater is the "plan B"  for many farmers, and although, it is widely known that pumping is at an unsustainable rate, groundwater pumping is largely unregulated.  The LA times notes: 

"The Central Valley aquifer extends for about 400 miles under the Sacramento and San Joaquin valleys. The subterranean water, some of which seeped into the ground 10,000 to 20,000 years ago, is California's biggest reservoir. Yet it has been largely unregulated and unmonitored. Most of the more than 100,000 wells that pierce the valley floor are unmetered and landowners have taken what they wanted."

    Perhaps we should put this in historical context.  Here is an interesting article, analyzing the climate variation over the last 1000 or so years.  I didn't realize that what we consider "norrmal" for California i.e. the 20th century, , is actually an unusually wet period.   The author notes

"Consider what happened in the American West in the early 20th century, when population grew roughly 50% from decade-to-decade, the largest regional growth spurt in post-colonial American history. People were lured by warm temperatures and abundant moisture. For much of that period, believe it or not, the West was a green paradise. Abundant moisture was so much du jour that allocation rights for Colorado River water, which have been contended ever since, were based upon what turns out to be the wettest period in nearly 1200 years. Had early 20th century planners had modern climatological analyses in their hands, it’s doubtful they would have been so profligate with water distribution from what really is the only big river in the Pacific Southwest."

   

For more analysis of the pre historic record, see also Nation Geographic : Could California's Drought last 200 years?, and this paper on the 9th -14th centuries - "medieval climate anomaly".

     We are naturally concerned about the problems here in the US, but we should probably also be aware of similar problems elsewhere.  For instance Sao Paulo, the largest city in South America, is also suffering from a historic drought.   The local reservoir has enough water to last until June.  The rainy season doesn't start until November.   Here is one report from PRI

"The region is in its worst drought in 80 years. The reservoir that supplies half the city is just over 10 percent full. The government has begun rationing water, though haphazardly.

Many people in São Paulo are worried their future may look a lot like what happened last year in the small, nearby city of Itu.

Last August, without warning, the city's homes had their water supplies shut off. Residents had to use public taps, and neighbors fought neighbors as dozens of people swarmed around the faucet. The outage went on for weeks, stretching into September. Itu resident Alexandre Oliveira remembers it as “a water war."

Oliveira volunteered as a water carrier for homebound neighbors, but others charged for the service and became known as “water traffickers.”

Emergency water trucks were eventually called in, but there weren’t enough. When they did arrive, some residents blocked the trucks with flaming barricades to make sure they didn’t leave before every house on the street got water.

But in some low-income neighborhoods, the water trucks never came at all. Elsa Barbosa, who lives in the favela of Chácaras Reunidas Ypê on the edge of Itu, eventually started to use water from a disused old well. “We had to boil it a lot,” she says. “There were stomach aches and vomiting.”

       

How about the future?  Well, according to a recent  UN Report, at current usage rates, the world will have 40% less fresh water than it needs in 15 years.   see .. Why fresh water shortages will cause the next great global crisis   What are some likely consequences?  Check out this site "World Water Conflict" for an in depth look at the history and future of water conflicts around the globe.