Tuesday, February 22, 2011

Drinking Recycled Water

Many areas in the US use more water than the local ecosystem can sustain. To compensate for addition need water is transported from other locations. Water from rivers are allocated to certain area to insure that the publics water needs are met. This is a costly process. Many cities have begun using reclaimed or recycled water that has been treated to remove solids and impurities. In the past this water has been used in sustainable landscaping or used to recharge groundwater aquifers. But for millions of people in the Orange County Water District in California this reconstituted water will become their future drinking water.

Purifying sewage is a long and intense process. It includes a hard scrubbing with filters, screens, chemicals, ultraviolet light and the usage of underground aquifers to further purify the water. City officials and others hope this will serve as a model for authorities worldwide who are facing drought conditions and water shortages due to climate change and the depletion of freshwater supplies.

The water undergoes reverse osmosis which involves forcing water through thin porous membranes at very high pressures. Peroxide and UV light are used to further clean and break down any remaining pharmaceuticals and carcinogens. District managers say the finished produce exceeds drinking water standards. However, the reclaimed water will not flow directly into kitchen sinks because of state regulations. The water will instead be injected underground to be filtered through aquifers that supply 2.3 million people will clean drinking water. Official say this project will produce more potable water and at a higher quality compared to the water plant it is replaces.


  1. Every time I get water out of the sink, I think about where it was before it got into my glass. Did the water I'm drinking come from someone's toilet and get purified in a sewage plant? It's amazing that water can be so throughouly purified to go from sewage to drinking water.

  2. While this sounds like a good re-use of water, I wonder about the energy costs associated with the process. Also, what percent of the water goes through this process, and what fraction of water in the aquifers is coming from this source? Some statistics on the new water plant and the one it is replacing would be interesting to see.