One of my favourite hikes is along Gold Creek. The river cascades over two spectacular waterfalls and meanders through the valley crystal clear and pure. The water, where the river is calm, is so clean it appears to be invisible; you can see the polished rocks in sharp relief 15 or 20 feet below the surface. As a teenager, I can remember how disconcerting it was to dive into one of the swimming holes. After climbing up the canyon face for a launching point, the surface of the water seemed to disappear and all you could see were the rocks far below.
Even though the water is clean and pure, walking across the stream stirs up the sediment that has settled between the rocks. As your boot disturbs the bottom, the fine sand and clay erupts in a cloud and spreads out over the creek. It is amazing that even in fast moving water, the sediment quickly settles and a few meters down stream it is running clean and pure once more.
The third stage of the NOAH system is a Multi-Stage Hays Cascade Portalock Hays Filtration system, which seeks to emulate the settling effect of the meandering river. The Hays’ filter consists of a series of chambers that calm the water down and let it slowly wind its way through the system. Each of the chambers is designed to take the water on a circuitous route, allowing for the maximum effect of the water to clean itself.
As the water travels from chamber to chamber the following reactions take place:
The heavy ions settle to the bottom of the chamber. The chambers are designed to extract the particles as they settle. Heavy metals are removed from the sediment and recycled. The remaining sediment is purified and safe for disposal or reuse depending on what is in the water.
Light volatile organic chemicals rise to the surface. At this stage the water is already infused with bacteria and oxygen that continue to break down the organics. A portion of the water from the top of the chamber is returned to the first stage of the NOAH system for further filtration. The gases produced are vented or sequestered for other purposes.
In the Sonication process, sound waves travel through the entire NOAH system so that the cavitation effect will continue through each of the chambers.
The environment has been optimized for the highly active bacteria to continue their aerobic digestion of organic solids.
The pure water once again tends to be found in the middle of the chambers and it is this water that is passed on to the next chamber.
The water that emerges from the last chamber is crystal clean and pure.