Kaye - Aha that explains the interest :) Good to know you live in a similar region too, so you know how it is to live under comparable circumstances. Btw I can easily spot the Folsom Dam with Google Maps.
Ken – The website you mention has some info in english too, see the links in my earlier post, or see the pulldown menu under the Union Jack in the upper right corner.
The Delta Works are initially made to protect us against flooding, but is just part of a whole complex system to control the flow of water in the region. Being the drainpit of our neighbouring countries, rivers are also a risk for flooding. A movable barrier like the Haringvlietsluizen regulates the flow of the main rivers to the sea for instance. As the majority of the land in the delta is below see level a system of ditches, canals, sluices and pumps regulate the amount of water not only keeping our feets dry, but also keeping the ground water at the desired level to maximize crop production, but also to avoid sinking (“inklinken” in Dutch) of land if the level is too low. Also sea water salinizates land along the shores making the soil less profitable, so we must keep that under control too. Besides that transport over water must remain possible, not to forget the delicate shellfish fishery. So water management makes it possible to combine all these elements and make them work together as good as possible. Quite a lot of effort has to be made......though.
So the dams, barriers, dykes etc. are the visible part of that plan / system, the Maeslant Barrier was the last project completing the Delta Works. Directions for getting to the Barrier see the first link in my earlier post. If possible visit that other massive project the Oosterschelde Storm Surge Barrier and the “Watersnoodmuseum” near Ouwerkerk / Zierikzee too.
I really hope you enjoy your visit.