Rosetta Branch (RB) is the Nile western branch, which is considered the main freshwater resource for the western governorates of the Nile Delta, in addition to El-Beheira governorate, Egypt. This work aims to investigate the effectiveness of applying six feasible water quality management scenarios for the RB at Kafr Elzayat (KZ) City, where two major pollution sources (industrial companies and the Tala Drain) are discharging their effluents to the branch. A hydro-ecological model for the branch was developed based on MIKE 11 modeling system (3 modules). The developed model was calibrated using field hydrodynamic and water quality records for the branch during the period from November 2014 to August 2015. The calibrated model results were considered a base case for the simulated management scenarios. According to the study results, diverting the Tala Drain effluents to the nearest main drain will significantly enhance the branch water quality, while diverting of the industrial companies’ effluents to the city sewer system will significantly enhance the water quality conditions downstream of the study. The expected scenario of decreasing the RB discharge, due to future climatic changes and/or construction of the new Ethiopian dams, will significantly affect the RB water quality status in a negative way. Urgent management plans, based on the presented scenarios results (or a combination of them), should be applied to enhance the branch water quality. The Tala Drain should be, at least, provided by a water quality treatment plant, and the branch freshwater discharge should be increased.

罗塞塔支流 (RB) 是尼罗河西部支流，被认为是尼罗河三角洲西部各省以及埃及埃尔贝黑拉省的主要淡水资源。这项工作旨在调查对 Kafr Elzayat (KZ) 市的 RB 应用六种可行的水质管理方案的有效性，其中两个主要污染源（工业公司和 Tala Drain）正在向该分支排放污水。该分支的水文生态模型是基于 MIKE 11 建模系统（3 个模块）开发的。开发的模型是使用分公司在 2014 年 11 月至 2015 年 8 月期间的现场水动力和水质记录进行校准的。校准后的模型结果被认为是模拟管理场景的基础案例。根据研究结果，将塔拉排水管的出水引至最近的主排水管将显着提高支管水质，而将工业公司的出水引至城市下水道系统将显着改善研究下游的水质条件。由于未来的气候变化和/或埃塞俄比亚新水坝的建设，减少 RB 排放的预期情景将以负面方式显着影响 RB 水质状况。应根据所呈现的情景结果（或它们的组合）应用紧急管理计划来提高分支水质。塔拉排水管至少应由水质处理厂提供，并应增加分支淡水排放。