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Top 10 Green Advances in Residential Building

On-site Water Treatment Solutions

Increasingly more countries are holding their noses and introducing carefully treated wastewater into the drinking water supply. (Singapore is currently the largest population to adopt this technology [source: Barringer].) However, when we talk about on-site water treatment solutions in home building, we're rarely referring to potable sewage.

Rather, the term "on-site water treatment" refers to the process of collecting, treating and reusing water that's not considered drinkable but might be suitable for other activities. By diverting drainpipes into collection tanks, homeowners can capture rainwater, snowmelt and the "gray water" that drains away after they shower, wash dishes or launder clothes. The water in these collection tanks is filtered and reused for flushing toilets, irrigating landscapes and cycling through closed-loop radiant heating and cooling systems.

No mere novelty, gray water collection and reuse can be essential to sustaining communities in sub-Saharan Africa and other drought-stricken parts of the world. These areas are also in dire need of affordable, sustainable construction materials.

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