First and second advice:

On May 16, 1953, the Deltacommission gave its first piece of advice: to raise the Schouwens Dike from 3 metres above NAP (Normal Amsterdam Water Level) to 5 metres above NAP. This was not included in the Deltaplan.

The second piece of advice from the Deltacommission was to close down the river Hollandse IIssel. This advice was of great importance, because if the dikes along the river IIssel were breached, an industrialised area with over 1.5 million inhabitants would be in danger. It was suggested to close the Hollandse Ijssel by means of a storm surge barrier near the river’s estuary. A movable dam was chosen that is only closed in the case of a storm tide, so as to not harm shipping traffic, and reduce interference with the the water's flora and fauna. The advice for closing the Hollandse IJssel was given in the same year in which the flood took place. One year later, in 1954, building was initiated.