This type of systems exploits the ability to absorb large quantities of water, and to evaporate metabolic needs surplus through the leaves, typical of wetland plants.
Mixed farming is often preferred in order to provide an aesthetically appealing impact.
In addition, the mix of different biological cycles enhances plant efficiency and lowers the influence of parasites. Transpiration capacity, and hence plant yield, is bound to a number of factors, the following are beneficial:
- windy climate and dry areas
- high temperature (summer months)
- scarce rainfall
The outlet is fitted with a collection well and with a pump for recirculating surplus water to the top of the plant if necessary.
Size is based on organic load concentration and on flow. Minimum recommended surface per inhabitant equivalent is 5 m².
Running and maintenance
Operations exclusively involve maintenance of the plants and monitoring of the loading and recirculation pump (if applicable).
Evapotranspiration wetland systems are constituted of a basin built with PVC sheets, heat sealed on the site. The bottom of such basin is filled with a bed of draining material, generally gravel, to house the sewage distribution system made up of micro-fissured plastic tubes.
Whereas, the superficial layer contains soil from the site, adequately selected during works stage.
The surface is planted with various perennial herbaceous plants and shrubs, chosen among the most suitable varieties, both technically and aesthetically wise.
The outlet is always fitted with a well in a size com- patible with incoming and rainwater flow, for housing the timer pump used for redirecting discharge water to the top of the plant when necessary.