Estwaste - Sustainable wastewater purification in Estonian small municipalities
Currently most of the wastewater purification systems in Estonian small municipalities do not work or work in an unsatisfactory way. The nitrogen (N) and phosphorus (P) which are discharged as pollutants in the lakes and rivers present a serious environmental problem not only in Estonia but also in the neighbouring countries. The main aim of the project was to design and build alternative and cost-effective wastewater treatment system prototypes (willow plantations, mechanical treatment plants and reservoir ponds for wastewater storage) in three small municipalities (Vohnja, Kihlevere and Kambja) in Estonia. As project ended, the WWPS are functional and their future sustainability has been secured. In two of the prototypes, the water quality in the outflow met the limits set for Nitrogen and Phosphorus according to Estonian legislation; the third site could not be monitored due to shortage of water. The use of willow plantations as vegetable filters decreases the cost of the third (chemical) stage of the wastewater purification system. This should enable small municipalities to operate their wastewater purification systems much more cost-effectively.