Earlier this month, Governor Jerry Brown signed historic groundwater legislation that will charge local water basin managers with the responsibility of protecting California’s groundwater aquifers from overdraft. There is no doubt that this legislation was the state legislature’s response to the severe, three-year drought California has been facing. As the state has experienced low amounts of rain and snowpack the past few years, Californians have turned to groundwater to meet their water needs. This increase in groundwater pumping has depleted groundwater supplies to their lowest level in a century and has caused the San Joaquin Valley to sink in certain areas. The recent groundwater legislation in California has motivated me to investigate where state legislatures might move next in their regulation of groundwater as environmental concerns around groundwater heighten and how that potential regulation might affect rural communities.
For those who do not know, groundwater is simply rainwater or surface water that has percolated and gathered in subsurface cracks and spaces. Groundwater supplies drinking water for 44% of the total US population and 99% of the rural population. In 2005, 68% of groundwater was used for irrigation. Considering the percent of groundwater used for rural drinking and irrigation, it seems that any regulation on groundwater will have a drastic effect on rural populations.
In my search to uncover information that could potentially provoke legislatures to develop future groundwater regulation, I began examining the environmental impacts of groundwater pumping.
According to G.L. MacPherson with the Department of Geology at the University of Kansas, Lawrence, groundwater contains 10-100 times higher concentrations of carbon dioxide than the atmosphere; thus, when groundwater contacts the atmosphere, that carbon dioxide degases into the atmosphere. This means that pumping groundwater to the surface adds to the production in greenhouse gas emissions. In his public comment submission to the California Air Resources Board, William Bourcier, Ph.D., sited MacPherson stating that MacPherson estimates that the carbon dioxide produced from pumping groundwater is equal to the sum of all volcanic carbon dioxide release. If this is accurate, then the carbon dioxide emissions produced by groundwater pumping may be something that is regulated by states concerned with greenhouse gas emissions.
What type of effect might regulation of emissions produced by groundwater pumping on rural communities in a state like Nebraska, where 50 of the state’s 93 counties are rural? Nebraska is a state that, in 2005, accounted for 9% of the nation’s groundwater withdraws despite being less than 1% of the nation’s total population.
The overall impact of regulation of this type on rural communities will, likely, depend on the amount of carb dioxide that is actually being produced by pumping groundwater to the surface and the individual state’s environmental regulation tendencies. It is tough to say whether a state, like Nebraska, so apparently dependent on groundwater will implement such a regulation.
3 comments:
Enrique, this is a great post. I think that California’s ground water laws are extremely interesting and this has become an area of interest to everyone as the drought has taken hold. I did not realize the concentration of carbon dioxide in the ground water and had no idea that the use of water would increase greenhouse gas emissions. It is shocking that those emissions could be equivalent to a volcanic eruption. Good, interesting post.
How safe is groundwater? I've read in various places that Davis gets its water from the ground, but there have been recent proposals to change the city's water supply from the Sacramento River. I can see that there are deposits in my tap water--when I fill a glass with tap water, the water's not clear. Opponents of the proposal cite the high costs of creating a new system, and increased costs of water bills. I think that if you're going to live here in the long-term, the city should change its supply. There's going to be costs (e.g. medical bills, buying purified water, etc.) anyway if groundwater is bad for your health.
I’ve recently become fascinated by California’s reliance on groundwater and the resulting groundwater policies and legislation, so this post was particularly interesting for me. Last year, I was able to work on a research paper regarding nitrate contamination of groundwater in rural San Joaquin Valley. I learned that one reason rural areas are more vulnerable to contaminated groundwater is because of the many residents of these areas rely on shallower wells than urban areas which are able to extract water from deeper, less contaminated groundwater. Additionally, many rural communities don’t have access to the type of treatment systems available in more metropolitan areas.
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