Public-private partnerships are increasingly being used in many countries as a common management technique to enhance the delivery of public services and major public infrastructure projects. Understanding the project characteristics and obstacles to a public-private partnership is key for those involved to improve implementation. This study focuses on barriers that arise from public-private partnership contact in field wastewater treatment plants and offers a methodology for evaluating the overall barrier for public-private partnership projects by analyzing the relationships between the barrier elements. A primary list of barrier factors and their eight latent project characteristics were collected through literature reviews, then using the Delphi technique to filter the barrier insights concerning project characteristics and develop the final list using field interviews. 207 valid questionnaires were obtained. The data was deconvoluted into crisp numbers using fuzzy set theory, and a second-order structural equation model was used to validate the conceptual model. The results of the study indicate that the availability payment capability group has the highest score of all the groups in this study. This study proposed a model that enables the private sector to measure and evaluate aggregate barriers in projects so that it is easier for decision-makers to determine whether they can choose the project or not