Alternative Water Systems

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There are two main ways you can improve your home's ecological impact when it comes to water: installing alternative systems for domestic and outside water use, and implementing an alternative wastewater system.

Alternative water supply

A growing trend in reducing reliance on grid-tied systems is a "catchwater" installation. This setup captures water on the roof and stores it in a large tank. When water is needed in the home, the catchwater can be filtered and delivered.

Catchwater systems serve a dual purpose: they improve a home's sustainability and independence at the same time as reducing the strain on grid-tied systems in areas with limited rainfall and declining groundwater supplies.

On their own, catchwater systems will not provide for all an average home's needs. However, if they are tied in with reduced-flow shower heads, low-flush toilets, and very efficient appliances (dishwashers and clothes washers), they can supply enough water for the whole house, or near enough.

The systems themselves are simple enough. You need a large, relatively clean roof area (steel is ideal), some pipes, a cistern to store the water, a filtration system... and plenty of rain!

Alternative wastewater systems

Wastewater falls into two main categories: graywater and blackwater. As the names suggest, greywater is cleaner than blackwater.

  • Graywater is the waste water generated by sinks, washing machines, and showers.
  • Blackwater is the waste water primarily from toilets and kitchen sinks.

Between 50% and 80% of wastewater is grey and contains valuable resources that could be put to better use than simply siphoning them away in sewage lines. Graywater systems work best when they are installed in new builds, as they can be designed to work almost entirely by gravity flow.

The simplest graywater system is a hose that goes from your clothes washer to the back yard. There are far more complex systems available, such as a planter setup which uses pumice to absorb all the waste from the graywater supply. The waste is used as plant food in the planters, while the cleaner water runs out the end and can be used to water outdoor plants (or flush toilets, though the plumbing for that is expensive).

Recycling graywater does require a few lifestyle changes, the biggest of which is to get rid of all your chemical detergents and replace them with bio-compatible versions. You don't want to poison your plants, after all.

Blackwater recycling is understandably more complex. The first step is usually a composting toilet, which accepts human waste and allows it to quickly degrade into a relatively rich organic fertilizer. There is little odor. However, regulations on composting toilets in the US are very strict – some states require removal of the contents by licensed professionals or just that it be buried – so make sure you research the subject before you rush out to buy one.

The next step in blackwater recycling is treating it in artificial wetlands. This is safe and effective (if the wetland is properly designed). The blackwater passes into a pit partially filled with gravel, which is home to millions of microbes that