2018/01/25     Tunis, Tunisia

Image: UNU-FLORES/Serena Caucci

In Tunisia, wastewater irrigation presents farmers with an excellent case for alternative water provisioning in times of limited freshwater resources. Experts are also starting to discuss whether wastewater may be an untapped resource for the replenishment of coastal aquifers which are currently facing heavy salt intrusion.

The potential of the safe use of wastewater in agriculture (SUWA) has been heavily discussed – but upon large-scale application, environmental, sanitary, and food production issues have emerged worldwide. In Tunisia this is no exception.

Addressing this concern, UNU-FLORES has established working relationships in numerous SUWA hotspots globally. Building on previous collaborations with the National Research Institute of Rural Engineering, Water and Forests (INRGREF) in Tunis, UNU-FLORES is now looking to take on new challenges in the Middle East and North Africa region.

The workshop co-organised by UNU-FLORES and INRGREF in Tunis (12–13 December 2017) is the first tangible result of two active years of collaboration that began in Lima. Spanning two days, the workshop combined presentations from experts and practitioners with field visits. The scope of the workshop was to capitalise on local stakeholders’ knowledge and establish a participatory process for the implementation of a nexus-oriented use of wastewater in agriculture.

On the first day, participants heard from Prof. Hiroshan Hettiarachchi, Head of the Waste Management Unit at UNU-FLORES, about the Nexus Approach and the value of looking at the Safe Use of Wastewater in Agriculture (SUWA) to better understand this approach. His talk was followed by a presentation from Manfred Matz (GIZ, Tunisia) on using this approach to find a solution to the conflict of interests over water resources from the water, energy, and agriculture sectors.

Upon providing the setting for reflecting on what sustainable policy and capacity development implementation would require, participants were then given the chance to build their thoughts on the actual situation of both wastewater use (presentation by Dr Olfa Mahjoub, INRGREF) and aquifers (presentation by Samir Gabsi, CRDA Nabeul) in Tunisia. Mr Gabsi introduced the managed aquifer recharge pilot plant in the Korba region meant to use treated wastewater to recharge the near coastal aquifers.

In the second session, Tiba Haggui (DGRE) gave valuable insights on the negative impacts that the practice of aquifer recharge could have on agriculture and the environment if no proper treatment of wastewater effluent is carried out. The DGRE has especially stressed on poor wastewater quality monitoring priori wastewater injection into groundwater.

The picture provided by the stakeholders and the first round of discussions among participants clearly demonstrated that a number of sociopolitical challenges needed to be addressed before a safe practice of wastewater use would be ensured in Tunisia. Addressing this gap, Dr Serena Caucci (UNU-FLORES) talked about the importance of participatory approaches in quantifying health/environmental aspects of wastewater use before integrated policies may be implemented.

In this important step, the assessment of microcontaminants in the wastewater-water-soil interface as introduced by Christian Jensen (TU Denmark) exemplified the benefit for policymakers when the health risk-related thresholds for crop consumers are defined. Mr Jensen illustrated how models, if empirically implemented, can result in reliable tools for scenario prediction in the context of wastewater use in agriculture.

Image: UNU-FLORES/Serena Caucci

Image: UNU-FLORES/Serena Caucci

On the second day, participants had the opportunity to witness first-hand the reality of wastewater management practices in Tunisia. They went on a day trip to the Wastewater Treatment Plant, the aquifer recharge site in Korba, and at the Farmers Association met with farmers who shared their positive experiences in wastewater application in agriculture at the local farms.

“This workshop highlighted that while we already have the technology and sufficient knowledge to capacitate a sustainable wastewater management and reuse in agriculture, what do we really need is the policy and stakeholder integration in the capacitation process, particularly with regard to regulation and monitoring programmes,” Hettiarachchi observed. “The involvement of stakeholders in the policy implementation process is a challenge that we have seen in many parts of the world.”

It was concluded that only with access to resources and information for Tunisian stakeholders are they able to assess their infrastructure reliability and consider implementation measures as well as better environmental monitoring strategy. Various partners and participants at the workshop expressed interest in contributing to these efforts, and plans were made to continue collaboration.