Determining the water footprint of a textile factory producing denim fabric and researching cleaner production practices for reducing

This study is the first study to calculate both volumetric and environmental impact Water Footprint (WF) of the denim industry and to evaluate the effects of Cleaner Production (CP) applications on WF. The study discusses the concept of WF for the denim industry, its existence, types and calculation, the Best Available Techniques (BATs) to be implemented within the scope of CP to reduce the environmental impacts caused by WF, and the contribution of denim production to sustainability within this framework. The boundaries of the research were determined as door-to-door, and the WF Network and ISO 14046 methodologies were used in WF calculations. For 1 ton fabric production of the enterprise that produces denim, WFblue, WFgrey, WFscarcity, WFeutrophication, WFEcotoxicity and WFalkalization were calculated as 67,95 m3, 72,6 m3, 50,06 m3 H2O-eq., 7,72 kg PO4-3-eq, 8.686,60 m3 H2O-eq. and 0,39 kg OH-eq, respectively. WF results show that denim fabric production creates more environmental pressure on water resources due to the wastewater generated in its processes rather than the amount of water consumed (WFblue < WFgrey, WFscarcity < WFEcotoxicity). UNEP/UNIDO CP methodology was used to reduce the volumetric and environmental impact WFs of the enterprise. Within the scope of the BAT concept defined by the IPPC directive, 9 BATs were determined by considering 4 basic approaches such as water saving, reuse of wastewater with/without treatment, and improvement of wastewater characteristics, and cost estimates and payback periods were calculated. In case of implementation of the determined BATs, a decrease of 41,73%, 51,45% and 31,20% was determined in the WFblue, WFgrey and WFscarcity categories, respectively. The decrease in WF achieved in the denim manufacturing company thanks to CP applications showed that the company could contribute to target 6 (lean water and sanitation) by 36,47% and target 14 (life below water) by 51,45% within the scope of UNEP2030 sustainable development goals. It is anticipated that the results will provide methodological and technical guidance for subsequent research and applications. Keywords: Water Footprint Network, ISO 14046, Cleaner Production, Best Available Techniques, Sustainability