The project has built up knowledge, experience and insight that makes it possible to make an on-site wastewater treatment system based on physical-mechanical functional principles, where a treatment step consisting of Forward Osmosis (FO) and Re-verse Osmosis (RO) is connected directly to a standard septic tank. Clean water is drawn out of the wastewater and retained substances are concentrated in the septic tank. The project has shown that the technology can purify the water to a very high quality on level with drinking water, suitable for laundry, toilet flushing and garden irri-gation purposes and which can be infiltrated into the ground without risk of ground-water contamination. The project has shown that the technology contributes to very low biological activity in the septic tank, which results in low emission of greenhouse gases and an extraordinarily high biogas potential from the sludge in the septic tank. The project has demonstrated a need for the core components of the plant to be adapted in order to realize a competitive finished product.