West-Flanders – Decentralized water purification systems


Household district

Decentralized water purification systems

For households and other buildings that are not connected to the municipal sewer network, decentralized water purification systems can be used to treat the effluent of wastewater before discharge. NBS using helophyte filters can be a great alternative for the treatment of wastewater from households and restaurants, improving the local water quality.

NbS such as constructed wetlands are installed in several Provincial Domains in West-Flanders to improve water quality of domestic wastewater coming from (public) toilets, taverns and restaurants. Within West-Flanders, also smaller water treatment plants are used to filter water of 1 household (called IBAs).

Type of landscape : Rural Landscape

Ecosystem : Small household district

Reeds plants

Reeds are often planted within constructed wetlands. These plants filter nutrients out of the water. (source: Province of West-Flanders)

Water quality parameters of the influent and effluent of wastewater will be monitored (e.g., pH, conductivity, oxygen level, floating substances, ammonium, nitrite, nitrate, total N, Kjeldahl-N, orthophosphate, total P, BOD, COD). The installation and maintenance of these systems can be funded by local authorities, Province of West-Flanders, VMM and/or within the projects of Water-Land-Schap.

Domain de Blankaart 1
Blankaart

Provincial domain De Blankaart: a reed field purifies water from de Blankaart castle (visitor center and governmental offices). (source: Province of West-Flanders)

Key concepts

Decentralized water purification systems, such as helophyte filters, constructed wetland, and IBAs (Individuele Behandeling voor Afvalwater, individual systems for treatment of domestic wastewater as known in Flanders) can provide a great alternative for treatment of domestic wastewater in small household districts located in remote locations that are not connected to the main sewer networks. These systems are targeted to remove suspended solids, nutrients and other components from water through natural processes, such as settling and filtration, adsorption into substrate media, as biological degradation.

Specific NbS tailored for the region

Decentralized water purification systems for urban and rural landscapes help lower the nutrient concentrations that flows into surface water in households where no other means of wastewater treatment is provided. These plant-based systems can vary from very small systems (IBAs) that purify water of 1 household, to larger purification systems where a few dozens or even more households (or restaurants, businesses, …) are connected to. Some of these systems are present in the provincial domains of West-Flanders (eg reed field in De Blankaart), others are present in the gardens of private persons (eg. IBAs).

Environmental Challenges

Water pollution, water quality, loss of biodiversity

Policy Support

Some systems are funded or subsidised by the government and/or local authorities, others are partly subsidised and partly paid by the inhabitants (IBAs).

Expected impact of NBRACER

NBRACER will offer support to further develop the existing knowledge on this topic with new insights provided through the project’s international framework. The project can help mainstream the implementation and the replication of the NBS and contributes to the active engagement necessary from regions to offer an integrated support system to combat the current and future climate challenges facing our landscapes.