The main purpose of this paper is to design a new way to maximize the profit of wastewater treatment plants (WWTP). The establishment of multiple goals impedes their simultaneous achievement. As a result, it will be enough to achieve a certain degree of satisfaction of each goal. Sometimes this approach can be extremely difficult, so minor violations of some restrictions are exceptionally allowed. Fuzzy goal-based scheduling can be considered a suitable tool for these kinds of problems. In short, WWTPs will have a suitable tool for achieving profit maximization, and, at the same time, there will be a new system to measure efficiency in the sector.