Recovering Non-conventional Water Resources

18 February 2020 - // Interviews
Simos Malamis
Coordinator of the HYDROUSA project

Creating circular economy business models by reusing water resources for agriculture, tourism and homes, HYDROUSA is showing results on three Greek islands with tremendous potential for replication and expansion. REVOLVE interviewed the coordinator of the HYDROUSA project, Simos Malamis, to learn more.

What are today’s water scarcity problems for the Mediterranean?

The Mediterranean basin is one of the most sensitive in the world in terms of water scarcity, with a gap between supply and demand across both time and space. The annual available surface and groundwater resources in coastal countries are approximately 1,080 square kilometers. Although this may seem sufficient, the water is irregularly distributed, with countries having reserves of less than 500 m3 per capita per year, (called “structural shortage”), and many areas having less than 1,000 m3 per capita per year (officially UN “water stress” level). Agriculture is the main consumer of water around the Mediterranean, making up over 72% of total consumption. Tourism during the summer months places severe stress on the limited water reserves. Water scarcity and the lucrative touristic activities often result in reduced agricultural activity, because there is not enough water for the irrigation of crops.

Agriculture is the main consumer of water around the Mediterranean, making up over 72% of total consumption.

The operation of desalination plants severely strains the energy grid. The practice of excessive groundwater pumping for irrigation, results in seawater intrusion into the aquifer and reduced crop yields. Existing wastewater treatment plants (WWTPs) are often too overloaded to cope with the high seasonal loads, while some regions are not serviced at all. In many rural and remote areas, wastewater management is confined to septic tanks or pits with adverse environmental consequences to land and groundwater. Malpractice is too often the case with inadequate quality of treated wastewater used for irrigation or discharged into water recipients. In addition, municipalities (always short of funds) are not able to sustain energy-intensive wastewater treatment processes.

How does HYDROUSA offer solutions to the Mediterranean water challenge?

HYDROUSA aims to help solve the water demand issue, the wastewater management problem, the loss of biodiversity and nutrients, while also addressing the availability of jobs, and the infrastructure strains presented at the peak of tourist season – all of which contribute to unsustainable water demand. HYDROUSA services will enable us to use rainwater and treated wastewater to water plants and for domestic non-potable applications such as toilet flushing. We will enrich aquifers with rainwater and stormwater, thus reducing the excessive amount of pumping for groundwater. The HYDROUSA project also recycles the nutrients contained in sewage after suitable treatment in order to reduce the use of inorganic fertilizers.

For the demand site, we have a customer awareness campaign that explains the benefits of the implemented technologies and the overall issue of water supply. This helps raise awareness on the demand side and ultimately will reduce water consumption by the consumer.

Can you provide insights into the concept and benefits of the “Clear-water loops” in relation to HYDROUSA?

HYDROUSA aims to setup, demonstrate and optimize low-cost innovative, nature-inspired and nature-based solutions (NBS) for the treatment of a variety of water streams, including wastewater, rainwater, groundwater, atmospheric vapor water and seawater to produce valuable resources which can then be used to enrich domestic water supplies and increase agricultural production, therefore boosting the economic activities of water-scarce Mediterranean areas.

HYDROUSA helps close all water loops at local levels, taking advantage of local resources, promoting the concept of decentralized on-site water, materials and energy conservation, treatment and reuse. HYDROUSA includes six demonstration sites at full-scale on three Mediterranean islands (Lesvos, Mykonos, and Tinos). The implemented solutions are complemented with innovative services, based on the formation of new value chains, involving farmer associations and water producers.

The HYDROUSA concept

HYDROUSA takes a circular approach of water, materials and energy recycling for food production. We consider that the nutrients and energy inherently contained in wastewater can be recovered and used in agriculture and for domestic use. To close the water loops, we are implementing low energy and carbon footprint approaches. The HYDROUSA loops are local and therefore long transportation costs are avoided and the benefits of resource recovery remain within the local economies.

Overall reduction of carbon emissions is achieved, while increasing biomass production, biodiversity and ecosystem resilience. The use of local water sources is part of an Integrated Water Resource Management (IWRM).

What are the objectives of the demonstration sites on the Greek islands of Lesvos, Mykonos and Tinos?

The inspiration of HYDROUSA came from our vision to create a green island which will be completely water- and energy-sufficient and that would attract tourists. The demonstration sites at three Greek islands will prove this concept. More specifically, the HYDROUSA demonstration sites will:

  1. Demonstrate that circular, nature-inspired and nature-based solutions work for supplying fresh water from non-conventional water sources.
  2. Demonstrate that circular nature-based solutions work for wastewater treatment and nutrient recovery, while creating further environmental and societal benefits.
  3. Show that the technologies are feasible within existing (legal) constraints and create economic return, hence create jobs and boost the economy.
  4. Make sure that the community and stakeholders are engaged in all parts of the value chain from the very beginning.
  5. Prove that skilled workmanship combined with modern ICT solutions create resilient and attractive long-lasting systems.
  6. Establish the water-energy-food-employment nexus and work with true cost accounting as tool for circular economy assessment.
  7. Deal with the unsustainable water consumption through the utilization of unconventional water resources in agriculture and for domestic use.

How does biomimicry apply to the water systems HYDROUSA plans to install?

A number of HYDROUSA water treatments methods rely on biomimicry. After a long investigation of various biomimicry methods, we decided to incorporate some of these into HYDROUSA methods, after adaptation to our needs. HYDROUSA includes the following biomimetic solutions:

  • A Mangrove Still plant will be built to produce fresh water from seawater to feed a greenhouse that will grow tropical fruits. The Mangrove Still’s design creates a low-cost and efficient method of desalinating seawater, built with recyclable, reusable materials. The technology is inspired from the mangrove which is a shrub that grows in coastal saline or brackish water.
  • The biocultivator design was the inspiration for the development of a compost cultivator; it is a self-irrigated home-planting system in a closed vessel having a composting process underneath. The “compost-cultivator” of HYDROUSA takes this design and upscales it with modifications to the compost process.
  • The Warka Tower is an atmospheric water collection design inspired by the desert beetle. It will be used to collect moisture from the air to be used in this water loop. Warka towers are low-budget, bio-inspired, recyclable and biodegradable, net-like structures that capture and condense water from air.

What is the replication potential of the HYDROUSA systems?

The HYDROUSA solutions have a high replication potential in the Mediterranean region but also in other water scarce areas. We already have interest from a large hotel in Cyprus, two other Greek islands, and a business in Egypt for the development of some of the HYDROUSA solutions.

Within the project, the HYDROUSA solutions will be replicated within 25 early adopter cases in Mediterranean coastal areas and islands in Italy, Spain, Cyprus, France, Egypt, Croatia, Israel, Turkey, Palestine, Lebanon, Morocco and Tunisia, as well as in at least six water-stressed rural or peri-urban areas from Bulgaria, China, UAE, Australia, Mexico, Chile, Malaysia, Argentina.

The replication activities will consist of soft actions which include:

  • Analysis of the impact of different policy and institutional requirements on the implementation of HYDROUSA solutions.
  • Preparation of feasibility studies, business cases and pre-assessment service concerning different geographic areas.
  • Development of a market/competitor analysis in light of market launch in a different geographical context.
  • Development of a credible replicability and transferability plan.
The central challenge of HYDROUSA is to close broken nutrient cycles.

The main ambition of HYDROUSA is to develop a new circular business model, which is suitable for Mediterranean and other water-scarce regions. The model is based on the exploitation of non-conventional water sources to produce water that is suitable for different uses (irrigation and domestic use) as well as added value products (agricultural crops, edible salt, compost, essential oils). These products will be exploited locally for the benefit of agricultural cooperatives, minimizing long supply chains and high transportation costs. This model strongly supports the concept of social justice and fairness in the utilization of resources among communities.


Funded by the EU Horizon 2020 programme, HYDROUSA consists of 27 partners involved in water management, agricultural activities, ICT, business/marketing, dissemination/communication spanning the whole water supply chain. Coordinated by the National Technical University of Athens (NTUA), HYDROUSA has a total budget of approximately €12 million and is part of the circular economy program for water under call CIRC-02-2016-2017.

Simos Malamis
Coordinator of the HYDROUSA project

Join Planet

We strive to communicate sustainability for a better world for the next generations.

Support us by becoming a member of REVOLVE Planet today.

Become a Member