Eco in Denmark: WATER. The household wastewater, acid precipitation and groundwater

Fresh drinking water, acid precipitation, soil water storage, as well as wastewater and groundwater, is a big problem or challenge in today's fresh water loss and biomass growth. Not only is it unhealthy for us, but also with our spill of chemicals, important vegetation is losing minerals to grow and the groundwater itself that is moving outside of the community sewer transportation would end up disturbing already fresh lakes,coastline and rivers that we are also using and animals are in. Big, growing problem... and the EU has decided that all the member countries within year 2015 will have to make sure the water condition is good.

Where to find one solution? On my very first stop on this trip, I cannot avoid telling about their very own constructed waterland system (økologisk pileanlegg)! With inspiration from Odsherred, "Fri og Fro"-ecovillage August 9 - 16:
 

 " We're refreshing our own grey wastewater in a special-designed evaportranspiration construction!" - The folder explains, which I got hold of at the ecovillage in Odsherred, Denmark. As well as our own wastewater, it also takes acid precipitation (sur nedbør) and precipitation as it evaporates (fordamper)!

HERE'S HOW:

A polyethylene-lined basin (the ecovillage in Odsherred has installed 6 basins) filled with soil is planted with clones of willow (Salix viminalis) (piler) grown as a short rotation coppice. The basin receives input from wastewater and precipitation and has no discharge, but the water is evapotranspired by the willow and nutrients are consumed by the willow biomass, which is cut down regularly. 

The species Salix viminalis was effective in evapotranspiring (fordampning). It was concluded that the yearly ETA (måling av fordampning) of the constructed wetlands is more than twice as high as potential evaporation calculated from Makkink. The average potential evaporation (Makkink) in Denmark is 582mmyear-1. The measured ETA from a constructed wetland (økologisk pileanlegg) in Jutland (Jylland) was 1332mmyear -1. (Source:Susanne Rosenild,2005).

The willows, which are fast to grow, are using the minerals in the water to grow and evaporate the water through its leaves. The evaporated water is completely clean,and the report also says the system is called "oasis effect", as it basically is a constructed oasis! Some waterland constructions also plant more vegetation and long rows of willows especially around such a site, to create yet more feedback to the ecosystem. The wastewater is conducted from the single grounds til four bottom tanks, where it gets pushed through some cords up to the waterland construction. Here there are some instruments to analyze the incoming water and water level. 

If there is something wrong in the system, the whole construction actually sends an sms and alarms one of the members of the ecovillage community! Also when there is too much wastewater. What an invention!

For more information, in danish and some english, read an environmental research report here.