Many of us have the privilege of opening a tap and water comes out. It is an everyday thing for us and we are used to this luxury. But, have you ever wondered how the water coming from your kitchen tap is treated so that we are able to drink it?
In the United States, about a century ago, water diseases like typhoid and cholera was common. To solve this problem, water providers started to disinfect surface water. The United States do uphold very strict policies when it comes to drinking water and its quality.
The Safe Drinking Water Act (SDWA) was passed in 1974 and it regulates the quality of drinking water. The Environmental Protection Agency (EPA) is in charge of regulating and enforcing health parameters.
This act allows the EPA to be able to test water at any facility that supplies water to the public. If a problem is found at any facility, that facility must inform the public and, until EPA tests show that the water is once again safe for public use, the facility will undergo tests.
Furthermore Consumer Confidence Reports must be released each and every year so that consumers can be able to see what is in their water.
In the Unites States there is an estimated 161 000 Public water Systems while Community water Systems supply over 286 million people with water in their homes.
How water is treated, depends on where the water comes from. Surface water will need more treatment as it is exposed to elements, while groundwater does not need as much treatment.
The most common treatment applies three steps of treatment namely coagulation (flocculation and sedimentation), filtration and disinfection.
In coagulation, flocculation removes the dirt and other particles suspended in the water. In this process, alum and iron salts or synthetic organic polymers are added to the water. This attracts the dirt, forming particles.
Then in sedimentation, the flocculation particles are allowed to settle naturally out of the water.
Filtration is then applied. IN this process, all the particles are removed from the water. This includes the removal of microorganisms, precipitates from other processes within the facility, clay, silts and other organic matter. In the end, filtration ensures that the water is clear and thus makes disinfection more effective.
In the disinfection step, chlorine, chlorine dioxides or chlorinates are added to the water. The amount can be monitored and maintained, allowing the facility to control the quality of water. Sometimes these disinfection products can react with organisms left in the water, but the EPA and the water treatment facility closely monitors this.
Information about your area’s drinking water is freely available. You can check it out at www.epa.gov./safewater/ccr