The impact of building embankments and reclaiming land along the riverfront on the dynamics of the river, scouring of the riverbed and on the stability of bridges was analysed in detail. Various heights of embankments and various waterway widths were taken into consideration to arrive at the proposed design.
The fundamental objective of the design was to ensure that the building of the embankments and narrowing of the waterway does not in any way raise the high flood level beyond what can be expected in the present condition of the river. A secondary objective was to ensure flood control in the low-lying areas of Ahmedabad.
Findings
The estimation of HFLs for a 5 lakh cusec flood, analysis of required embankment heights and existing riverbank levels showed that, of the three different waterway widths, a width of 275 m was optimal to achieve the objectives of the design.
