Saturday, April 19, 2014

You drank WHAT?!??

Most people have no clue where their drinking water comes from. I once contracted Giardia from a drinking fountain in Ocean City, Maryland, and after a pretty terrible week of vomiting and diarrhea, have been much more sensitive to what I am drinking. I’m also much more aware of where my water comes from.

Q: Why is it important to clean and recycle water & where does drinking water come from i finally can hope that these only two questions can hopefully been answered and be removed of my mind. Kind Regards.
- Natalin I

A: There are many reasons why we need to clean and recycle water. Fundamentally, they all come down to the fact that there is relatively little naturally pure water left in the world. About 3.4 million people die each year from water related diseases.

Most drinking water comes from springs, streams, and rivers (surface water) or from wells (groundwater). In some places (such as NE Thailand) it is trapped from rainwater. However, all of these have potential problems. For example, if you collect rainwater from your roof, how do you keep birds off that roof?

In Saudi Arabia and a number of other arid and/or coastal countries, most drinking water is provided by immense desalination plants. As you can imagine this makes that water rather expensive. A side effect with this kind of water is that it is usually disposed of as waste into septic tanks... waste which seeps quickly into the local shallow groundwater. The groundwater in and around Jeddah, Saudi Arabia, for instance, is highly polluted with industrial chemicals and biologic contamination, and the groundwater levels are rising because of the dramatically growing human population. This polluted groundwater is now sapping building walls, and at least one hospital must pump water 24/7 out of the surrounding ground – and then dispose of it elsewhere so the hospital walls do not collapse. 

Consider surface water: if someone pollutes a stream near its source (e.g., cattle or other animals defecating), then everything downstream is contaminated. Giardia (sometimes called "Beaver Fever") and Clostridium (which shut down the Minneapolis city water supply for several weeks) are particularly nasty examples, and both are resistant to chlorination. In the 19th and early 20th Centuries, it was common for campers and hikers to drink stream water in the Rocky Mountains and Cascades Range with impunity. Not anymore: when I camp or hike I bring my own (safe) water, or a powerful micropore filter. Industrial feed lots or pig-raising farms are particularly dangerous offenders - major threats to safe drinking water. 

Now consider groundwater. I live in the (very wet) Pacific Northwest of the United States, and my groundwater comes from a well field deep under a large, 12 million-year-old basalt flow north of my city. The water originates as rain, and has been subsequently filtered by soil and basalt rock before it reached the aquifer where it is now pumped from. However, there are places in the US and elsewhere in the world where hydrocarbons (both NAPL and DNAPL forms), dioxins, and other terrible chemicals have seeped into the groundwater due to human carelessness: an abandoned gas station with rusting tanks, or a military base dating from the past century when waste was not thoughtfully disposed of. 

Recently, large parts of West Virginia have not had safe drinking water for weeks due to an "accidental" dumping of chemicals by a coal mine service company into a reservoir. I put "accidental" in quotes here, because the offending company has a long history of deliberately violating the Safe Drinking Water Act, including recent helicopter photos taken by CNN of highly illegal pumping and disposal of toxic wastes into nearby streams. In several places in the US, hydrofracking ("fracking") wells were not cemented in properly, and residents can literally light with a match the methane that has seeped out of their kitchen faucets. There are Superfund sites where highly carcinogenic dioxins, acids, and other exotic industrial chemicals have been released into the earth. These chemicals tend to move as plumes through the aquifers towards any well that is pumping water out of the aquifer. While biological contaminants can often be filtered (or boiled) out of drinking water, chemical contaminants that are in solution usually cannot. 

The United States and the Developing World have some of the highest standards on water quality in the world - but the large majority of the human population does not have these protections. There is a cholera epidemic in Haiti that has been going on for years, caused by fecal pollution of drinking water sources following the 2010 earthquake there. Cholera is a major childhood killer.

Here are several helpful websites that will guide you in your study of drinking water and pollution:

I hope this adequately answers your questions(s).

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