Physico-chemical study of raw wastewater from Outat El Haj city, Morocco Hassan Ech-Chafay, Mohamed Najy, Fatima Zahra Talbi, Abdellatif Elghazouany, Mohamed Lachhab and Driss Belghyti E3S Web Conf., 234 (2021) 00022 Published online: 02 February 2021 DOI: 10.1051/e3sconf/202123400022