Background

Expanding informal neighbourhoods has impacted the natural hydrological processes (evaporation, evapotranspiration, groundwater recharge, infiltration and surface runoff) by contaminating and altering the distribution of rainwater once it hits the ;(Konrad & Booth, 2005).  The contamination is further exacerbated by the lack of formal infrastructure in informal neighbourhoods. This has seen emergence of micro pollutants: Pharmaceutical and Personal Care Products (PPCP), Polycyclic Aromatic Hydrocarbons (PAHs) microplastic etc. in water bodies and increase in their associated health impacts.

Sustainable Drainage Systems (SuDS), in particular constructed wetlands, a well-established method to mitigate these impacts but require large areas of horizontal space which is at a premium in cities, making them only a downstream SuDS option (CIRIA, 2015).

Hydroponics, a soilless method of agriculture, has traditionally been used to maximise crop yields; by optimising the plant’s roots access to nutrients and oxygen. The root zone is considered the major component within phytoremediation. A hydroponic phytoremediation system offers a solution to engineering these processes in the form of a vertical wetland or bioretention vertical green wall, bring ecological services into the space-constrained streetscape of urban realm, particular informal settlements.

Attached growth organism can handle higher loading rates with shorter hydraulic retention times suggesting that the attached biofilm is more efficient in organic digestion than that of the suspended organism. The roots of the plant have a significant surface area and as such create the perfect location for biofilm, roots change the chemical, physical and biological properties of the immediate vicinity known as the rhizosphere but have symbiotic to the microorganism in the rhizosphere that has beneficial for water purification.

An important component of hydroponic is the medium used to grow the plants. The medium needs to be inert and with moisture retention. This medium allows the roots access to the nutrients/water and air but also create the ideal eco-system for the development of the biofilm. Improving the media would allow the maximization of efficiency of the hydroponic phytoremediation system.

Community initiatives have demonstrated a disconnection between top-down structures and everyday practices in informal settlement water management. As a social innovation, community led project, this phytoremediation SuDS potential to support a transition towards water management that benefits both social (ownerships) and ecological systems (mental health) within informal settlements.

This project looks to bio-mimic the natural purification methods through engineering a hydroponic system that maximises the characteristics listed above though the development of new novel media. To develop prototype innovative hydroponic SuDS, as s social innovation, that is not constrained by site specific removing the barrier for its installation into the informal settlements. Thus removing micro-pollutants and in doing so improving the health of local communities.

Aims and objectives

The main aims of this research project is to develop a novel phytoremediation SUDS through the optimisation of existing SuDS, in particular the enhancement of rhizosphere symbiotic relationship with the biofilm through development of a new natural media. Thus, creating social innovation that link technical and socio-economic developments and rehabilitate existing ecosystem services but also retrofit new ecosystem service into existing urban realms, improving the health and wellbeing of the urban populations, particulary the informal settlement population.

Objective innovative natural multi-purpose media that’s enhance

1. the biofilm and
2. rhizosphere ecosystem          
   1. Access to oxygen and nutrients
   2. pollutants
3. water retention
4. structure to anchor plants

Objective engagement to create Social innovation hydroponic SUDS

1. Community engagement
2. Pilot study

 Agroalimentaire

 Affaires maritimes et pêche