2011. december 25., vasárnap

Drinking Water Safety

Drinking water sources
Contaminants in drinking water

In nature, all water contains some impurities. As water flows in streams, sits in lakes, and filters through layers of soil and rock in the ground, it dissolves or absorbs the substances that it touches. 

 Minerals in drinking water

Some of these substances are harmless. In fact, some people prefer mineral water precisely because minerals give it an appealing taste. However, at certain levels, minerals, just like manmade chemicals, are considered contaminants that can make water unpalatable or even unsafe. Some contaminants come from the erosion of natural rock formations. 

Other contaminants are substances discharged from factories, applied to farmlands, or used
by consumers in their homes and yards. Sources of contaminants might be in your neighborhood or might be many miles away. Your local water quality report tells which contaminants are in your drinking water, the levels at which they were found, and the actual or likely source of each contaminant. 

Drinking water
Some ground water systems have established wellhead protection programs to prevent substances from contaminating their wells. Similarly, some surface-water systems protect the watershed around their reservoir to prevent contamination. Right now, states and water suppliers are working systematically to assess every source of drinking water, and to identify potential sources of contaminants. This process will help communities to protect their drinking water supplies from contamination.

Drinking water sources

Drinking water safety
A clean, constant supply of drinking water is essential to every community. People in large cities frequently drink water that comes from surface-water sources, such as lakes, rivers and reservoirs. Sometimes, these sources are close to the community. Other times, drinking water suppliers get their water from sources many miles away. In either case, when you think about where your drinking water comes from, it’s important to consider not just the part of the river or lake that you can see, but the entire watershed.

The watershed is the land area over which water flows into the river, lake or reservoir. In rural areas, people are more likely to drink ground water that was pumped from a well. These wells tap into aquifers, the natural reservoirs under the earth’s surface, that may be only a few miles wide, or may span the borders of many states. As with surface water, it is important to remember that activities many miles away from you may affect the quality of ground water. Your annual drinking water quality report will tell you where your water supplier gets your water.

飲用水源

 飲用水污染物在自然界中,所有的水含有一些雜質。由於溪流中的水流量,坐落在湖泊,並通過在地面上的土壤和岩石層的過濾器,它溶解或吸收的物質,它觸及。礦物質的飲用水這些物質有些是無害的的。事實上,有些人喜歡礦泉水,礦物質,正是因為給它一個有吸引力的味道。然而,在一定的水平,礦物質,就像人造化學物質,被認為是污染物,可以使水難吃,甚至不安全。一些污染物來自天然岩層的侵蝕。其他污染物是從工廠排出的的物質,適用於農田,或使用消費者在自己家中和碼。污染物的來源可能是在你家附近,或可能是許多英里遠。你當地的水質報告告訴飲用水的污染物,發現他們的水平,各污染物的實際或可能的來源。飲用水一些地下水系統已經建立了井口保護方案,以防止污染他們的油井物質。同樣,一些地表水系統周圍的水庫流域保護,以防止污染。眼下,各國和水的供應商正在系統地評估每一個飲用水源,並找出潛在的污染物來源。這一過程將幫助社區,以防止污染飲用水供應。

飲用水源

飲水安全

一個乾淨,穩定供應飲用水是必不可少的每一個社區。在大城市,人們經常喝的水從地表水的來源,如湖泊,河流和水庫,。有時,這些消息是貼近社會。其他情況下,飲用水的供應商獲得從源水,許多英里遠。在這兩種情況下,當您認為您的飲用水來自哪裡,它的重要的考慮因素不只是部分河流或湖泊,你可以看到,但整個流域。流域的水流入到河流,湖泊或水庫的土地面積。在農村地區,人們更容易喝從井裡抽水的地下水是。將這些含水層井的挖掘,在地球表面的天然水庫,可能只有幾英里寬,或可能跨越許多國家的邊界。與地表水一樣,重要的是要記住,許多英里,離你的活動可能會影響地下水質。你的年度飲用水水質報告會告訴您,您的水供應商那裡得到你的水。