Years ago, waste water was dumped into the oceans, lakes and waterways of the United States without a second thought to the recycling of waste water. No one realized that the runoff from manufacturing plants and city sewage systems was going to have such a negative impact on the environment. Once it was realized that the pollution of our water systems was having a detrimental effect on the world, recycling of waste water became a top priority for industries and cities.
What needed to be done was the water had to have enough chemicals and pollutants removed to be added safely back into the ecosystem and the water cycle. Over the years, the techniques have been refined to the point that the recycling of waste water produces a clean enough product that when it is put back into the environment, there is little risk to plant and animal life. These techniques are far from perfect, but they can have a positive impact on the quality of the water that is released into the waterways.
The recycling of waste water is a multifaceted process. First screening and clarification must take place to remove any foreign materials and solid waste from the waste water. Once this is complete, microorganisms are introduced to the partially clarified water and any remaining materials will be broken down for a second clarification process. These microorganisms will break down during clarification and will be removed from the water, along with the waste that has been removed through the digestive process of the organisms. Nearly all the microorganisms leave the water after the clarification process, but sometimes a few will survive.
Once the second clarification has been completed, the final phase of the recycling of waste water can begin. Either ultraviolet radiation or chlorine, followed by sulfur oxide, will be used to remove any stray microorganisms from the water and to complete the treatment process. This water may not be considered potable, but can safely be returned to the waterways and reintroduced to the water cycle, to find its way later into the ground water system. By the time the water returns to ground water, it is indistinguishable from any other clean water on the planet.
Though the recycling of waste water almost seems like a dirty process, involving chemicals and microorganisms, the alternative to this is dumping untreated sewage and dangerous industrial runoff into the oceans, rivers and streams. Though in an industrial age it is virtually impossible to return the water to the earth in a perfect state, by treating the wastewater, we an minimize the damage that is done by our daily activities.