A non-partisan, neutral perspective supporting diversity in the color of water

Monday, June 26, 2017

Greywater-induced soil hydrophobicity

A great new and important paper in Chemosphere on a topic that rarely receives much attention in the spectrum of water colors.


Greywater (GW) reuse for irrigation is a common method of reducing domestic consumption of fresh water. Most of the scientific research and legislation efforts have focused on GW's health risks, while less attention has been given to its environmental outcomes. One of the environmental risks of GW irrigation is its possible effect on soil hydraulic properties. This research examined the ability of GW to induce soil hydrophobicity, as well as its degree and persistence. Fresh water (control) and three model GW solutions representing raw, treated and highly treated GW were used to wet fine-grained sand. Every treatment was subjected to five cycles of wetting, incubation (at 5 °C or 30 °C) and drying (60 °C). After each cycle, capillary rise was measured and the contact angle (CA) was calculated. Samples were also tested by the Wilhelmy plate method to retrieve advancing and receding CA and reservoir surface tension. Water repellence of the sand, as implied from the CA, increased with increasing GW concentration and was highest in the sand coated with the model raw GW and incubated at 5 °C. However, none of the treatments resulted in what is considered to be “water-repellent soil”. Furthermore, when raw GW-coated sand was immersed in water, its surface tension was significantly reduced relative to the other treatments, implying a release of surface-active compounds from the sand into the water. It was postulated that untreated GW may induce sub-critical water repellence in sand. However, this effect is sensitive to biodegradation and washing processes and is therefore temporary.

What are hydrophobic surfaces?

Sunday, June 11, 2017


Introducing the ultimate tiny residence, the Ecocapsule. A new entry into minimalist living, the microhome "...is capable of accommodating between one and two people, and is able to function for almost a full year off the grid. As well as the power-producing components of the pod, it is also capable of producing both grey water and drinking water."

All at the modest price of $91,000.
* * * 
I tell my micro students everything I teach them is important, but the truth is that some things are more useful than others, and opportunity cost is near the top. 
~Economist Emily Oster

Saturday, June 3, 2017

Greywater Goes RVing

How does one sell the idea of a $280,000 to $400,000 recreational vehicle?

Make the RV green by incorporating greywater into the buyer's camping experience!

Introducing the EarthRoamer XV-HD Camper series.

The Good Stuff about the EarthRoamer XV-HD Camper:

  • Modded ground-up version of Ford F-750 Chassis.
  • Features EarthRoamer™ quiet solution engine and generator combo. The XV-HD hardly makes any noise, unless and until the car’s stuck in mud and you are pushing the accelerator down the floor.
  • Fully resistant to weather conditions, climatic changes etc.
  • Company installed rooftop solar array for energy storage.
  • Up to 20,000-watt hour lithium ion battery bank!
  • Intelligent, self-sufficient hydraulic leveling mechanism.
  • Luxury interiors with custom designed decorations and usage items.
  • Additional floor plans are available for further customization options.
  • Over 100 Gallons storage capacity for Blackwater and Graywater reserves.

."...gray water is sort of an environmentally friendly water that is partitioned in another container in the vehicle.  You have the option of dumping this water reserve for the benefit of plants and shrubbery in the wilderness around you."
* * * 
No one should be able to enter a wilderness by mechanical means. 
~Garrett Hardin, Biology Professor, 
coined the concept Tragedy of the Commons

Friday, May 19, 2017

Greywater and the Red Planet

Star Date -  47634.44.

Mars Desert Research Station (Utah).

Mission - Aerospace Medicine.

Captain's Log:

  • The MDRS was built by the Mars Society in Utah in 2002.
  • The society is a volunteer-driven, not-for-profit organisation dedicated to promoting human exploration of Mars.
  • It is the second of four planned Mars surface simulation exploration habitats.
  • The site includes living quarters, a GreenHab to grow plants and process grey water, an observatory and an engineering area.
  • Crews of six volunteers at a time live at the facility for two weeks doing experiments and simulating life on Mars.
  • Mars 160 Mission - Underway Now! Follow the latest on the Mars 160 Mission by visiting the Mars 160 Website.
  • Visitors please note: From September 24, 2016 to May 31, 2017, the Mars Desert Research Station is closed to visitors
* * *
It's not going to do any good to land on Mars if we're stupid. 
~Ray Bradbury