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Background: Blockages due to fat and oil deposition in sewer lines comprise a large part of all sewer blockages around the world. For instance, about 50% of sewer line blockages in Britain and the USA are due to fat and oil deposition. There are various methods to solve this problem, each of which has advantages and disadvantages. The aim of this study was to introduce solutions and protocols to reduce existing problems associated with fat, oil, and grease deposition and to prevent future problems.Methods: All the relevant papers used in this study were retrieved from electronic databases such as Science Direct, Google Scholar, and Free Patents Online. Finally, about 50 relevant papers and reports were chosen for further analysis. Practical experiences of the authors of this study and consultation with experts in the field were helpful in final conclusions and proposing protocols.Findings: Analysis of the scientific resources along with the practical experiences of the authors in solving fat, oil, and grease depositions in municipal sewer lines particularly in Mashhad, Iran, and consulting with experts suggested four general methods to prevent sewer line blockage. These methods included the implementation of fat and oil management practices and installation of grease removal devices in kitchens, appropriate design of new sewer lines, modification of existing sewer lines and regular sewer preventive cleaning program.Conclusion: Sewer line blockage due to fat and oil deposition is one of the big challenges for water and wastewater industry in the world and Iran. Various methods have been proposed to combat this problem. Appropriate use of the suggested methods can reduce or prevent possible problems while reducing the associated financial and environmental costs.