Nature-based Solutions on existing infrastructures for resilient Water Management in the Mediterranean

Carrión de los Céspedes Living Lab, Spain

FWC-NbS 1: Waster treatment and storage (Type A + B)

Location:  Carrión de los Céspedes, Seville (Spain)

Climate: Hot-summer Mediterranean climate

Area: 4.1 Ha

Objectives: Improve wastewater reuse to irrigation and quantity and quality of treated water storage.

Challenges: Droughts and water scarcity; stored water quality; water pollution and run-offs; diffuse contamination of aquifers from fertilizers; evaporation; CC impacts; water digitalization.

Description: The experimental centre is a Living Lab for the co-creation, experimentation and evaluation of water innovative products, wastewater treatment and circular economy sector. It also works as a wastewater treatment plant for the municipality. The Centre has numerous NbS for wastewater treatment (constructed wetlands -CW-, peat, sand and green filters, high rate algae ponds, and permeable reactive barriers), sufficiently representative to up-scale the results to a real scale. The investment is mainly public.

  • Agriculture: Irrigated crops (sunflower, olive grove and almonds) and rain-fed crops (sunflower and olive grove).
  • Communities: Rural population and economic activities linked to agriculture and service sector. Employment opportunities and training activities in the Centre, in close collaboration with the local government.
  • Water policies: Directive 91/271/CEE.
  • Data: There is updated data of the operation and performance of CW.


Constructed Wetland​

A comparative assessment and optimization among different seven types of Constructed Wetland combination will be pursued at real pilot scale. It will be evaluated the performance removal both for physic-chemical and microbiological species for reclamation and irrigation reuse, according to the water discharge and reuse regulatory framework.
CWs will be fed with the outlet of an already existing Imhoff Tank, previously pre-treated by an existing pre-treatment (screening and aerated grit and grease removal chamber) with the exception of one CW that will fed with the pre-treated wastewater.

Floating Garden​

A floating garden system will be developed to be used as a shading system to reduce the evaporation rate from water storage infrastructures, in this case, irrigation tanks.
The objective is to reduce evaporation rates while providing a range of other biodiversity benefits, such as providing habitats for aquatic and terrestrial species, or acting as connecting corridors between habitats.
In order to be functional, this system has to meet a number of requirements, which are detailed below:

  • Plant species must be: non-invasive, with low water requirements, autochthonous and with asexual reproduction
  • No contact of plant roots with stored water
  • Self-sufficiency: capacity to store rainwater to avoid dependence on irrigation
  • Easy maintenance: avoid the clogging of the water channels with the plant debris
  • Modular
  • Scalable

Ultrasounds emissions

The equipment of ultrasound emissions will be implemented in an experimental reservoir tank for water reuse irrigation located in the Experimental Center of Carrión de los Céspedes.
The wastewater treated by CWS will be derived from the collection chamber to the central tank in the image, which will function as a buffer tank to distribute the water to two experimental tanks, one of them intended for experimentation with ultrasound for the reduction of microalgae and E. coli removal for reuse in agricultural irrigation.