ABSTRACT
Introduction In The Netherlands systematic intervention in natural water conditions started already ten centuries ago. Through the building of mounds, dams and dikes the inhabitants of the lowlands enclosed tidal embayment and reclaimed land in the tidal areas and estuaries. At present without the protection of dunes, dikes and dams about 65% of the country would be inundated either by sea at storm surges or by the rivers at high discharges. Flood disasters caused by storm surges and severe river floods occurred in The Netherlands several times each century, even during the second half of the 20th century. The occurrence of such destructive events is mostly the decisive factor that forces government and responsible authorities to take action and to improve protection measures against floods.
