Excellent from Dr. Singh. I lack experience associated with the specifics of your country, but the drainage of land, dredging of streams, and other hydrologic modifications such as modifying flooding regimes with dams can cause or contribute to loss of wetlands and in coastal areas expansion of salt influence when channels are enlarged and deepened. Climate change/sea level rise have various models with limited ability to forecast specifics. There may be ways to mitigate the hydrologic modifications. Early rice growers sometimes used small dikes to help limit landward expansion of high tides, and also stored water to be released sufficient to keep highest tides or wind driven seas from damaging rice plantations. You might search out some papers by Dr. Art Parola, University of Louisville in Kentucky relative to groundwater dams to raise and rehydrate floodplains where channels were entrenched. The groundwater dams in floodplain or marsh would bury logs and clay to impermeable or restricted flow layer to help maintain hydration and ability to flood or saturate more frequently.