Wastewater treatment plant based on the combination of natural treatment systems, such asconstructed wetlands and ponds, following the concept of waterharmonica.Constructed wetlands are water purification systems that reproduce the processes ofcontaminant elimination which occur in natural wetlands. Therefore, constructed wetlandtechnology operates as a complex ecosystem made of the following elements:
Traditionally, there are two types of constructed wetland depending on the type of water flow:surface flow or subsurface flow. In Surface Flow Wetlands, SFW, or Free Water Surface Wetlands,FWS, the wastewater flows over the substrate whilst in Subsurface Flow Wetlands, SSFW, orVegetated Submerged Beds, VSB, the water flows underground through the interstitial spaces ofthe filtrating bed.
NWTP is based on natural wastewater technologies which are characterised by large surface-requirements (3-5 m2/PE).
The NWTP get the recovery of the investment between the 10 and the 20 years.