Tackling droughts with technology: safe rainwater harvesting and reuse

By: Matt Grocoff , Contributing Writer
In: Green Renovations

An illustrated look at how to harvest rainwater

There's an old story from where I grew up in Georgia about a farmer who had a leaky roof. A traveler came by and asked, "Hey farmer, why don't you fix that leaky roof?" With a whisper of confident wisdom the farmer answered, "Well, when it's raining it's too wet to work. And when it's dry, it's just as good as any man's roof."

Rainwater harvesting is becoming more popular as more areas around the country experience record droughts. Rain barrels were the original go-to device to harvest rain. But, like the farmer said, when it's raining you don't really need a rain barrel, and when it's dry there's really not enough water in that barrel to make a difference.

The latest trend is to go beyond the barrel and create a fully integrated rainwater harvesting and reuse system for the entire house.

A good sustainable water system for your home includes both healthy harvesting as well as conservation and reuse. For harvesting you need:

  1. a clean catchment area (roof)
  2. good gutters
  3. flush diverters
  4. storage (cistern/tank)
  5. overflow valves
  6. a distribution system

You can read my article here about things you must know before harvesting rain.

The great news is there are some extraordinary new technologies that make safely using that rainwater inside your home very easy. Here are a few you might want to look in to.

How greywater and rain water harvesting works


Aqualoop is a water recycling system from Europe that allows you to combine rain water and grey water that you capture from your showers, dishwasher, washing machine, and bathroom sinks.

The grey water is piped through the Aqualoops membrane reactors and is filtered to produce high quality water that would be safe enough to drink. It will even treat sewage water. This water can then be reused for washing clothes, flushing toilets, watering lawns and, in some municipalities, you may even be able to use it for showering and drinking.

Nexus eWater System

This treats gray water on site, which allows you to capture water from your sinks, showers, and washing machines. Rather than dumping that water into the sewer pipes, the water passes through the Nexus treatment system and passes up to 200 gallons per day into a tank reservoir that can then be used for irrigation or flushing toilets.


Biomicrobics is an integrated wastewater treatment system that has a membrane bio-reactor called Bio-barrier. It is certified for both gray water and black water (toilet water) treatment. This technology opens up tremendous opportunities for water reuse in homes, which could result in extraordinary reduction in water use from municipalities.

Codes vary dramatically from city to city, county to county, and state to state. Be sure to contact your local regulatory authority to determine what systems are allow in your area.