One of the environmental issues in urban planning is finding a suitable site for constructing infrastructures such as
water and wastewater treatment plants. There are numerous factors to be considered for this purpose, which
make decision-making a complex task. We used an integrated fuzzy logic and multicriteria decision model to select
a suitable site for establishing wastewater treatment plant in Kahak, Iran. We used super decision software and a
geographic information system (GIS) for scoring the parameters. The western part of Kahak was found to be a
suitable place for constructing municipal wastewater treatment plant. Our findings indicated that decision makers
and policy makers would be able to achieve better results concerning the most suitable location for wastewater
treatment plant easily through combining these two models.