Taourit-Oujda corridor (T.O.C.) is a geological entity of north-eastern Morocco with a total area of 4000 Km². The drinking water supply in this arid region still faces challenges that meet a growing demand for a shortage of fresh water. This shortage is mainly due to the scarcity and irregularity of the precipitations, the overexploitation of the water resources, and the decrease of the capacity of storage dams that are the main source of drinking water supply in this area. This work aims at estimating deficit (to 2040) for drinking water provided by Machraa Hammadi dam and proposing favourable drilling sites to strengthen drinking water supply through the identification of groundwater resources that can be used in quantity and quality. To do this, a multi-criteria analysis (MCA) covering geological, hydrogeological and hydro-chemical aspects using the Geographical Information System (GIS) was carried out. This study shows that T.O.C. aquifer is more productive in the south-west of it, in the centre near the El Aioun municipality and in the north-east at the town of Sidi Bouhouria. According to Moroccan standards, defining the quality norms of surface waters, waters destined for irrigation, and of surface waters used for the production of drinking water, the groundwater in the center and north-east areas is also with good to medium overall quality groundwater.

Assessing heavy metal concentrations in wetlands and identifying sources of metal contamination are critical steps in protecting wetlands. Using seven sampling stations, we evaluated the spatial variation of some heavy metal concentrations in surface waters of the Mohammedia wetland and a selected segment of the El Maleh wadi that feeds the wetland. Field observations made it possible to identify and map the pollution discharged into El Maleh wadi, carrying heavy metals into the wetland. The analyses showed that the concentrations of lead, manganese, and cadmium far exceed the thresholds relating to fish life in 100% of sampling stations. All the evidence points to heavy metals contamination of surface water in Mohammedia wetland, generated by industrial activities, wastewater discharges, and leachate from the old landfill located upstream.

In urban context, wetlands play a proven role in retaining pollution, alleviating the impacts of climate change, and enhancing the well-being of citizens. Managing these ecosystems requires formulating an integrated development policy reconciling protection, enhancement, and the satisfaction of economic and social needs. Achieving this goal requires the establishment of a holistic and collaborative vision that engages all stakeholders. This paper focuses on rehabilitating the El Oulfa Pond located in Casablanca, outlining the role of civil society and scientists in producing quantitative and qualitative data. This work aims to facilitate an informed decision-making process concerning the pond's development. The quantitative analysis enabled us to characterize the water quality and identify the biodiversity of El Oulfa pond. The outcomes underscore that 60% of the bird species whose presence around the pond is confirmed require a habitat in a wetland. Some species identified are classified as rare, or endangered. 23% of the recorded plants are indicative of a natural area of ecological Interest. These characteristics are important to take into consideration when developing the site. The biodiversity in El Oulfa pond could be jeopardized by significant water pollution. Indeed, the parameters of surface water monitored between 2015 and 2021 show concentrations that exceed the Moroccan thresholds relating to fish water quality. This suggests that for these parameters, the ecosystem does not provide conditions conducive to the maintenance of biodiversity. This pollution also poses challenges for residents who have expressed, during the open forum and interviews conducted in this study, the critical need for depollution and securing the pond before initiating any development. Building upon the study's findings, development strategies have been proposed to enhance the site and promote collective stewardship.