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美国有6万个给水事业,用地表水为水源的占18％,但占全部供水量的63％。全国供水人口2.3亿。日平均取水量约17亿m~3,公用给水系统为1亿m~3,平均水消费量为636L/人·日,其中63％是家庭用水,美国给水小规模的多,有4.7万个,相当给水事业的78％ 而占供水量的4％。小规模的自来水多以地下水为水源,大部分消毒,也有一部分不消毒。按供水对象可以分为集中(市政)给水、半集中给水(属单位,也供居民)和私人家庭给水,多为井水或泉水。 美国疾病控制中心(CDC)于1966年开始水性疾病暴发的监测,1971年和环保局(EPA)合
There are 60,000 water supply utilities in the United States, accounting for 18% of the total surface water supply, but accounting for 63% of the total water supply. National water supply population 230 million. The daily average water withdrawal is about 1.7 billion m 3, the public water supply system is 100 million m 3, and the average water consumption is 636 liters per day, 63% of which is domestic water. The United States has a small-scale water supply with 47,000 , Equivalent to 78% of water supply and 4% of water supply. Small-scale tap water is mostly groundwater, mostly disinfected, and some are not disinfected. According to the object of water supply can be divided into centralized (municipal) water supply, semi-centralized water supply (unit, but also for residents) and private households to feed water, mostly well water or spring water. The United States Centers for Disease Control (CDC) began monitoring the outbreak of waterborne disease in 1966 and, in 1971, with the EPA