Abstract Floods and corresponding plains are very important to the river to fulfill its complex bio-geomorphological functions. These functions vary in importance from one river to another river. Hence, in this work an attempt has been made to evaluate bankfull discharge and its width. The analysis is carried out at seven Central Water Commission (CWC) hydro-meteorological sites on main stem of Ganga River. The bankfull discharge is assessed using an approach of ‘partial duration series’ rationally in flood frequency analysis for each CWC site. The region covering at-least a part of its flood plain, i.e., bankfull width is derived using rating curve of respective CWC site and validated using pre-post monsoon cross-sections and google-earth imageries at all CWC sites. The present methodology overcomes the problem of incised and semi-incised rivers. The results are indicative of the likely minimal river space (both essential and desirable) for the seven locations, but unexplained anomalies exist in terms of discharges along the length of the river.

中文翻译：

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恒河中平原（半）切开恒河现场岸边流量宽度水文评估框架

摘要 洪水和相应的平原对河流实现其复杂的生物地貌功能具有重要意义。从一条河流到另一条河流，这些功能的重要性各不相同。因此，在这项工作中，已经尝试评估满堤排放及其宽度。分析是在恒河干流的七个中央水务委员会 (CWC) 水文气象站点进行的。在每个 CWC 站点的洪水频率分析中，使用“部分持续时间序列”的方法合理地评估了堤岸流量。至少覆盖其洪泛区一部分的区域，即河岸宽度是使用各自 CWC 站点的评级曲线得出的，并使用所有 CWC 站点的前季风横截面和谷歌地球图像进行验证。本方法克服了下切和半下切河流的问题。