Grenoble flood 1859
Encyclopedia
Historically, centenarian floods did extensive damage in the Isere Valley
. In October 1859, it rained continuously for five days. A warm wind melted the snow, and the temperature suddenly increased from 12 to 19 degrees on November 2. The simultaneity of those two events resulted in an exceptional flood. In a single night, the water in Grenoble
rose at a rate of 15 to 20 cm per hour.
s. The violence of the water current aggravated the destruction, especially city infrastructure
such as the Saint-Laurent bridge. Six people died during this flood, and the hospital had to retain its dead until November 17th, because they couldn’t bury them. Casualty figures stayed low because the river rose relatively gently in the actual city of Grenoble.
From an economic point of view, stocks of goods were destroyed. Stocks that had been set up by traders in order to prepare for big markets in November, like the market of Saint Andre, and military stocks, were washed away.
There was at that time a wall around Grenoble, dating from Roman times. Parts of these remains are still visible. The objective was to prevent flood water from entering into the city. The cost of the 1859 flood damage to these walls added up to over 400 000 French Francs, valued in the local currency at the time of the event.
dams and flood barrier
river development. These developments have limited the subsequent extent of flooding. A government entity has been created, called “le Syndicat Mixte des Bassins Hydrauliques", which now manages the landscapes and provides prevention against the potential risks of modern flooding.
Despite the construction of dams
, which were designed to protect the people living next to the Isère river, the town of Grenoble is still threatened by floods.
Although for more than a century big floods haven’t occurred, that doesn’t exclude the threat. Eleven ruptures were noticed after the flood of 1859. These ruptures occurred at weak spots including boucle du bois Francais, courbe de la taille (athough the dam here is being reinforced), boucle de Giere, courbe du campus. In 2001, the Isere river attained a volume of 1000 m³/s , which caused local flooding almost everywhere there were modern weak spots. Some dam
s in the Grenoble catchment area are very weak, in bad condition and not large enough to contain flooding.
It was only in 2011 that the government took action, and decided to invest in 112 projects, called SYMBHIthat will take seven years and will help reinforce the dam system. These were financed on the basis that it is cheaper to prevent that to repair. This project is 42% financed by the General Counsil of Isere, 30% by the government, the ‘’intercomunalite ‘’ finances 20% and the "Eau Rhône-Méditerranée et Corse" 8%. Projects will start in pont de Charat and will end in Grenoble centre. In case of a major crisis
, the losses could be evaluated at 400 or 500 million euros if the a disaster similar to that of 1859 were to happen again. Modern technology
can predict a flood in the Isere river
6 to 10 hours before it occurs.
An estimated 300,000 Grenoble citizens are directly exposed to floods. Finally, even though the flood of Isere in 1859 caused much damage, only 6 people died.
. On the statue there is a lion's head instead of a dragon.
Isère River
The Isère is a 286 km long river in southeastern France, in the Rhône-Alpes région. Its source is in the Alps on the border with Italy, near the ski resort Val d'Isère. It flows into the Rhône River in Pont-de-l'Isère, a few km north of Valence...
. In October 1859, it rained continuously for five days. A warm wind melted the snow, and the temperature suddenly increased from 12 to 19 degrees on November 2. The simultaneity of those two events resulted in an exceptional flood. In a single night, the water in Grenoble
Grenoble
Grenoble is a city in southeastern France, at the foot of the French Alps where the river Drac joins the Isère. Located in the Rhône-Alpes region, Grenoble is the capital of the department of Isère...
rose at a rate of 15 to 20 cm per hour.
Grenoble Flood 1859
On November 2, water levels in the city reached 5.35m above the average low water mark, rising so quickly that people who went out with dry feet couldn’t go home half an hour later. The whole inner city was flooded. In the streets, the water rose from 1m 32cm to 1m 50cm, making normal movement impossible and forcing people to move in raftRaft
A raft is any flat structure for support or transportation over water. It is the most basic of boat design, characterized by the absence of a hull...
s. The violence of the water current aggravated the destruction, especially city infrastructure
Infrastructure
Infrastructure is basic physical and organizational structures needed for the operation of a society or enterprise, or the services and facilities necessary for an economy to function...
such as the Saint-Laurent bridge. Six people died during this flood, and the hospital had to retain its dead until November 17th, because they couldn’t bury them. Casualty figures stayed low because the river rose relatively gently in the actual city of Grenoble.
From an economic point of view, stocks of goods were destroyed. Stocks that had been set up by traders in order to prepare for big markets in November, like the market of Saint Andre, and military stocks, were washed away.
There was at that time a wall around Grenoble, dating from Roman times. Parts of these remains are still visible. The objective was to prevent flood water from entering into the city. The cost of the 1859 flood damage to these walls added up to over 400 000 French Francs, valued in the local currency at the time of the event.
Existing risks
Since then, public works have been done on the rivers, hydrolyticHydrolysis
Hydrolysis is a chemical reaction during which molecules of water are split into hydrogen cations and hydroxide anions in the process of a chemical mechanism. It is the type of reaction that is used to break down certain polymers, especially those made by condensation polymerization...
dams and flood barrier
Flood barrier
A flood barrier, surge barrier of storm surge barrier is a specific type of floodgate, designed to prevent a storm surge or spring tide from flooding the protected area behind the barrier...
river development. These developments have limited the subsequent extent of flooding. A government entity has been created, called “le Syndicat Mixte des Bassins Hydrauliques", which now manages the landscapes and provides prevention against the potential risks of modern flooding.
Despite the construction of dams
DAMS
Driot-Arnoux Motorsport is a racing team from France, involved in many areas of motorsports. DAMS was founded in 1988 by Jean-Paul Driot and former Formula One driver René Arnoux. It is headquartered near Le Mans, only 2 km from the Bugatti Circuit.- History :The year after its foundation,...
, which were designed to protect the people living next to the Isère river, the town of Grenoble is still threatened by floods.
Although for more than a century big floods haven’t occurred, that doesn’t exclude the threat. Eleven ruptures were noticed after the flood of 1859. These ruptures occurred at weak spots including boucle du bois Francais, courbe de la taille (athough the dam here is being reinforced), boucle de Giere, courbe du campus. In 2001, the Isere river attained a volume of 1000 m³/s , which caused local flooding almost everywhere there were modern weak spots. Some dam
Dam
A dam is a barrier that impounds water or underground streams. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees are used to manage or prevent water flow into specific land regions. Hydropower and pumped-storage hydroelectricity are...
s in the Grenoble catchment area are very weak, in bad condition and not large enough to contain flooding.
It was only in 2011 that the government took action, and decided to invest in 112 projects, called SYMBHIthat will take seven years and will help reinforce the dam system. These were financed on the basis that it is cheaper to prevent that to repair. This project is 42% financed by the General Counsil of Isere, 30% by the government, the ‘’intercomunalite ‘’ finances 20% and the "Eau Rhône-Méditerranée et Corse" 8%. Projects will start in pont de Charat and will end in Grenoble centre. In case of a major crisis
Crisis
A crisis is any event that is, or expected to lead to, an unstable and dangerous situation affecting an individual, group, community or whole society...
, the losses could be evaluated at 400 or 500 million euros if the a disaster similar to that of 1859 were to happen again. Modern technology
Technology
Technology is the making, usage, and knowledge of tools, machines, techniques, crafts, systems or methods of organization in order to solve a problem or perform a specific function. It can also refer to the collection of such tools, machinery, and procedures. The word technology comes ;...
can predict a flood in the Isere river
Isère River
The Isère is a 286 km long river in southeastern France, in the Rhône-Alpes région. Its source is in the Alps on the border with Italy, near the ski resort Val d'Isère. It flows into the Rhône River in Pont-de-l'Isère, a few km north of Valence...
6 to 10 hours before it occurs.
An estimated 300,000 Grenoble citizens are directly exposed to floods. Finally, even though the flood of Isere in 1859 caused much damage, only 6 people died.
The Flow of the Isere during the flood
There is currently a probability of one in ten that the flow of the Isere river could attain 900 square metres per second (m/s), which would cause very little overflow. There is a probability of one in a hundred that this could rise to 1200 m/s, which is regarded as a dangerous scenario. There is a one in two hundred probability of flow rates of 1600 m/s,as in the flood of 1859.Le Serpent et le Dragon Fountain.
Next to the Saint-Laurent Bridge in the Place de la Cimaise, there is a fountain which represents the struggle against the waters. It was built by Pierre-Victor Sappey in 1840. The sculpture consists of a lion and a snake. Next to the fountain is written a French proverb: "La serpen et lo dragon mettront Grenoblo en savon” which means "the snake and the dragon will destroy Grenoble" The serpent symbolizes the Isère river and the Dragon symbolizes the Drac riverDrac River
The Drac is a 130 km long river in southeastern France, left tributary of the Isère. It is formed by the confluence of the Drac Noir and the Drac Blanc, that both rise in the southern part of the Massif des Écrins. It flows through several reservoirs, including the Lac de Monteynard-Avignonet....
. On the statue there is a lion's head instead of a dragon.