Flexibility – Inland waterways are less flexible like roads. transportation can be carried out only with some fixed points, individualization or molding for public benefit is not possible. Navigability – Diversion of water for irrigation reduces river flow and further siltation broke down the navigability very easily. Safety risks – Risks to human life and health most prominently involve drowning or, in cold waters, hypothermia, if a passenger or crew member falls overboard.