Windmills and Dams

Kinderdijk Wind Mills in the Fog

This morning we had the choice of walking and a boat ride, or biking among the 19 windmills of Kinderdijk. We're on a 250 square km. Waard or island between the rivers. In 1100 this was all swamp. Then they started digging canals to channel the water to the rivers and create arable land. In 1400 they put dikes along the rivers to prevent flooding and windmills to pump the water up about 5 feet to a higher canal or the river. This area has preserved its windmills, 17 of which are still occupied by families and two as museums. The one we toured was from 1630 with a large, heavy square structure on top. Most were built in 1738-40 and have smaller, lighter round tops. If the wind is light, you pull down two or four canvases to catch the wind. “Three sheets to the wind" is unstable. What was striking was the measuring pole which shows the various water levels: low tide on the nearby river was about 3 feet higher than the canal, yellow high tide about 9 feet higher and the worst flood seen in this area was about 12 feet above the canal and 9 feet above the land. 

Model of the Delta Works

We sailed on to Willemstad and then took a bus to the Delta Works. A flood here in 1953, from a 30-hour storm on the North Sea broke the existing dikes and killed 1800 people. A new series of dams and storm surge barriers was designed to shorten the Dutch coastline, reducing the number of dikes that had to be raised. The original plan was a series of dikes that would turn the water behind the dikes into a large freshwater lake, useful for farming behind the dikes. But work was stopped in 1973 because of the ecological concerns for turning this large sea water estuary into a fresh water lake. The plan was changed to build the Delta Works, which would leave this an estuary, but by closing the gates under extreme weather conditions, protect the people and land from flooding. It took 8 years of construction and was completed in 1986. As part of the project they had to stabilize  the sandy bottom below the water by creating a carpet of cloth and rocks for an area of 6 miles in length by 1 mile. Then build a permanent structure of pylon islands with gates 6 to 12 meters high. The gates have been closed 27 times in 33 years.

The Surge Gate we visited

We ended our day with the crew show, which had us all laughing. Jörn read a passenger's diary.