The environment kept its miraculous balance due to God's power till man, intentionally or non-intentionally, started to corrupt God's creation. This led to a huge problem, namely damaging the environment. Hence, the researcher decided to study and analyze costs, environmental returns of water industrial facilities of Toshka project of agricultural expansion under the title " A proposed Model to Measure Cost & Return in Water Facilities with the aim of Assessing Environmental Performance- Applied Study on Toshka Project" . This is due to the importance quality of accounting information for decision-making and conducting a research study of the opinions of a sample of those responsible for industrial facilities of Toshka Project. For the theoretical part of the studyk, light was shed on care of these facilities of environmental issues and nature of environmental costs borne by these facilities. The researcher also examined concept and nature of environmental costs and means of approaching them. As for the applied part, it is the research study and building a measurement model of cost & return. Through a questionnaire form distributed on those working at industrial facilities at Toshka Project, results and recommendations to achieve goals of the research were attained, the most important of which are: Firstly, Results: There is no moral relationship of statistically significance between rationalizing costs in water facilities and the results of the environmental performance of these facilities. There is no moral- relationship of statistically significance between cost rationalization, revenue of water facilities & the amount of environmental pollution. There is no moral relationship of statistically significance among the results of suggested model for measuring the cost & revenue of water facilities & rationalizing environmental performance of Toshka Project. Secondly: Recommendations: Paying attention to laying out qualified cadres in the accountant units & operational ones related to environment. Activating the laws that make the facilities conform to their responsibilities towards the environment & paying attention to research & study for indicating the role of environmental legislations & their effects on environmental costs. Paying attention to evaluation as a tool for improving the facilities performance periodically as well as research and study of accountancy information in evaluating  environmental performance .