The Earth is not flat; it is hollow, like a soup plate. Not everywhere, I agree. You will think of the Great Salt Lake in Utah or the Dead Sea. I am thinking of the polders of the Netherlands, these lowlands surrounded by dykes which protect them against water: rainwater collects there and transforms them into lakes or swamps. It must therefore be evacuated.
In Quebec, it’s snowmelt time. Even if this year there does not seem to be any ice jams, several rivers are full, like some lakes. Wetlands and floodplains are no longer used to accommodate excess water. Now, new residential neighborhoods occupy the square. Residents are preparing for the flooding of their land and basements. Our firefighters take out their pumps, the cities raise the level of alert.
You understand that when the Government of Quebec announces work to protect our shores, in Sainte-Marthe-sur-le-lac or in the Bas-Saint-Laurent, my Dutch heart beats faster.
In the Netherlands, care has been taken to protect the land and its inhabitants since the Middle Ages. The saying that God created the earth, but the Dutch created the Netherlands, contains an element of truth.
Often people ask me how come I am so tall. I always answer that in 1916, the dike would have given way, the one that protected the village of Andijk, in West Friesland, where my parents were born. A severe fall storm would have caused a breach. And as the water level, at high tide, reached 1.80 m, all those whose nose was lower would have drowned.
PHOTO KOEN VAN WEEL, AGENCE FRANCE-PRESSE ARCHIVES
Reinforcement of the ems canal embankment, in Woltersum, the Netherlands, in 2012
The dam held
In reality, the dike never gave way. It was my great-grandfather, whom I never knew, who, in his capacity as head of water management, organized the works of last resort in order to prevent a flood1. But, above all, the land protected by this dyke is 5 meters below the level reached in 1916!
The storm of 1916 was not the only one. In 1917, another tidal wave hit the southwest of the country. And in 1953, the same region suffered a historic storm. The floods killed 1,900 people there. Those of you who have visited the Netherlands have seen the multiple roadblocks erected to prevent a repeat of these events.
The dyke was completed in the year 1250 and maintained ever since. However, the warming period of the Northern Hemisphere, from the VIIIe in the XIIIe century, at least in Northern Europe, caused a series of devastating storms that changed the face of the country. Regions have become islands, villages have disappeared, but our dike has held.
On the other hand, in the long run, the dykes and the pumping had an effect contrary to the objectives. If in the polders – those old lakes and peat bogs – the water is kept low in order to dry out the fields, the dry peat will settle down and you will have to pump even more.
In the same way, the rivers have been dammed there in order to protect the land against occasional flooding from rivers and rivers, in times of rain or snowmelt. Here too, protection can create a risk: when rivers contain too much water, in their new too narrow bed, the water level risks rising exponentially. It will still be necessary to raise the height of all the dikes. Unfortunately, water being fluid, it moves around and will find the weakest spot in the defense system.
Currently, human-caused climate change, this time global, is replicating and amplifying these issues, including rising sea levels. The dunes are at risk and the sea will prevent the water from the rivers from flowing.
After a century of building dams and fortifying existing defences, the Dutch realized that a paradoxical approach was needed. You need to leave more room for water.
Some of the polders will be flooded when the water flow is too great. Land along the rivers will serve as a reservoir. Their inhabitants will be displaced. Channeled rivers will resume their sinuous shape to slow the flow of water.
PHOTO OLIVIER JEAN, LA PRESSE ARCHIVES
Works in Sainte-Marthe-sur-le-Lac, one year after the dike broke in 2019
In Quebec, water takes up as much space as in the Netherlands. It looks like we are getting as much snow as in the past, if not more. Storms, downpours and storm surges will become more frequent, tidal waves stronger. Bank reinforcements in one place will cause more pressure further away. So our government’s measures are just a band-aid.
Failing to take measures that actually reduce climate change, Quebec should adopt a proactive approach to the management of rivers and lakes rather than waiting for floods and riprap on banks. In the short term, any residential construction in the riparian zones is to be avoided.