THE REMARKABLE FLOOD CONTROL MECHANISMS OF THE NETHERLANDS

Imagine waking up one morning and finding everywhere around your home swallowed up by water because there has been a flood or a bad storm overnight. Imagine that this nightmare didn’t just occur occasionally, but very regularly. Well, just before your imagination gets the best of you, such was the reality of the people of the Netherlands.

In this article, you will discover the immense flooding crises and struggles that have plagued the Netherlands for many centuries, claiming hordes of life and terribly altering the topography of the area.

The Netherlands is a densely populated country in Western Europe informally called Holland. It is flanked by Rivers Rhine and Meuse, and as a result of its low elevation and flat topography, 2/3 of its area is vulnerable to flooding. This may not seem remarkable in any way, till you discover that only 50% of the entire country is more than a few feet above sea level. What this translates to is that there are some persons living the nightmare you barely imagined a few minutes ago.

As far back as 325BC, Greek geographer, Pytheas, pointed out that more persons died struggling against water than against men in the “low countries”. These low countries refer to areas like Netherlands where the land is below sea level and so susceptible to immense flooding sagas. Again, a first century author, Pliny commented in his book, natural History, on the devastating effects the inhabitants of these areas consistently battled with as a result of continuous influx of the ocean’s vast tide into stretches of land.

Even keeping livestock and living ordinary lives like people of other areas was a luxury that that they couldn’t afford since all undergrowth had been pushed far back.

In an interview with The World From PRX, Chris Zevenberg, a Professor of Flood Resistance of Urban Systems at the IHE Delft Institute for Water Education, stated that the Netherlands faces flooding risks from three major sources: storms and storm surges from the seas, flooding from surrounding rivers and floods from heavy rainfall.

As depressing as these occurrences have been to the Netherlands over the years, they have risen to become the vanguard in water engineering, with one of their flood prevention projects, Delta Works, gaining global acclaim by the American Society of Civil Engineers as one of the seven wonders of the modern world. Today, they are consulted for training all over the world to teach other engineers on how to adapt to the global

warming threats of flooding and storm surges in the near future. Astounding, right? How the tables have turned!

The Netherlands definitely didn’t toss a magic wand over their land and compel these feats to happen in one moment. Rather, what has grown today to receive global recognition began over 2,000 years ago and has continuously morphed through various stages and processes to become what it is today. Multiple flood disasters and consequent losses further strengthened the quest for improved strategies to combat the flooding risks.

STRATEGIES IMPLEMENTED TO CURB FLOODING

1. PEAT SWAMPS: The flood-threatened areas were at first covered by extensive peat swamps – rows of coastal dunes and natural embankments which prevented the seas from washing away the swamps.

2. EARTH DIKES: When overtime, the seas began to break through these natural defenses, the inhabitants resorted to raising earth dikes with a protective layer of seaweed to protect their crops against occasional flooding.

3. TIMBER DIKES: The earth dikes however, brought about new challenges, as after each flooding, the difference between the water level on one side and the land level on the other side of the dikes grew such that whenever the dikes overflowed or was breached in any way, the destruction was more fatal than that of the flooding itself. The inhabitants of the area then resorted to the much less successful timber dikes, which eventually were eaten up by the ship-worm.

4. STONE DIKES: The people of the Netherlands thereafter transited to using stone dikes, which caused grave financial strain on the inhabitants, as the stones had to be imported from other countries, the Netherlands having no natural occurring rock.

Netherlands dikes

Today, the Netherlands still very much make use of dikes as part of their flood control strategies. However, they are now made with a core of sand, covered by a thick layer of clay to provide waterproofing and resistance against erosion. Areas without a foreland have a layer of crushed rock below the waterline to slow wave action. Up to the high waterline is often covered with carefully laid basalt stones or a layer of tarmac, while the remainder is covered by grass and maintained by grazing sheep.

5. DAMS: In areas where peat swamps were developed for draining water from the land by digging a system of parallel drainage ditches, the land areas became wet again and due to the continuous subsidence of the land, it became increasingly tasking to drain excess water. Therefore, dams were constructed on the river banks to prevent high water levels flowing back upstream and overflowing cultivated lands.

6. WINDMILLS: The dams brought about another disadvantage as they blocked off shipping and economic activity. Thus, the inhabitants turned to polder windmills, which could raise water at high levels. This system is still in use today, although more technological advancements have brought about more effective flood control strategies.

RECENT DEVELOPMENTS

The Netherlands saw much technological developments in the 20 th century, which led to the undertaking of larger projects to further improve safety against flooding and reclaim large areas of land. The most popular of these works are the Zuiderzee Works and the Delta Works. The Zuiderzee Works spanned from 1920 to 1975 and consisted of a system of dams, land reclamation and water-drainage works for the damming off of the Zuiderzee, a large shallow inlet of the North Sea. The more famous Delta Works spun off as a solution to dam all the river mouths and sea inlets, since the sea defenses in the South West river delta were inadequate to withstand a major storm surge. It consisted of laying 10,250 miles of dikes around 350 structures, 13 dams, including barriers, sluices, locks and levees.

Delta Works project

In 1997, the world’s largest storm surge barrier was constructed around the Rijmond area, keeping the economic activities of the area in mind.

FUTURE CONCERNS

With the staggering statistics of a flood chance of once every 10,000 years in the Netherlands, one would think that the Netherlands have vanquished flooding completely.

Sadly, flood control experts warn that complacency would culminate in immense fatalities in the near future. Professor Zevenberg revealed that although the old defense systems have been groundbreaking so far, they may fail in the near future, as forecasts unveil potential sea level rises that could overwhelm the Netherlands’ flood control measures. Consequently, the country is now preparing for such failure.

The bane for the new Room for the River project is a strategy of living with the water instead of fighting against the water by allowing for the periodic flooding of indefensible land. Instead of merely responding to flood disasters, this new strategy encumbers anticipating and preparing for them through multi-level systems.