The Pont du Gard and the Pont de Roquefavour

Le Pont du Gard
© Benh Lieu Song 2014

It is impossible to imagine the effect which this granite chain linking two mountains produces, this rainbow made of stone which fills the whole horizon,  these three levels of porticos which eighteen centuries of sun have gilded.   I have seen several of the wonders of the world, but I have never seen anything which is as beautiful, as grand, as pure, as this magnificent granite epic which is called Le Pont du Gard.

 — Alexandre Dumas

To reinforce their prestige and domination throughout their many conquests, all the emperors of ancient Rome established towns during a thousand year period.

Searching for a place to settle, the Romans considered water as a “symbol of life”. To be able to build fountains, water tanks, latrines, artisan workshops or thermal baths, indispensable to the life of the city, the Romans had to be able to channel water as close as possible to the populations.

Aqueducts — a word formed from the two Latin words aqua (water) and ducere (to drive) — were therefore constructed by the builders of ancient times and nowadays Roman aqueducts, still visible, allow water to travel from source for a long way.

Before undertaking the building work of an aqueduct, the Roman constructors made very careful studies of the area, studying the environment, the condition of the soil in the vicinity around the source of drinking water.  Then the infrastructure was adapted according to the gradations of the terrain. One can therefore see that in Nîmes, the sources of the rivers Airan and the Eure, close to Uzès, are situated thirty kilometres to the North West of the town, and higher up, but they had to follow the contours of the hills to maintain a gradual slope and assure a regular water flow.

The watertightness of the canals, a particularly crucial element of the work, is equally an engineering masterpiece:  On a base of mortar and gravel, a U-shaped hannel was erected, and coated internally with reddish tile mortar. A cradle-shaped arch, also rendered with cement, covered the work. This description testifies to us the extraordinary skill of the engineers.

 

Known as the highest bridge in the Roman Empire, the Pont du Gard, 49 metres high and around 275 metres in length, is situated in the South East of France.

Built, we believe, between 38 and 52 A.D., the bridge required and used more than 50,000 tonnesof stone sourced from the quarry at Estel 400 metres upstreamof the works.   Around a thousand men were trained to work in these enormous building sites and perfect immeasurably difficult works.  “one doesn’t know what one ought to admire more, the size of the stones or the precision with which they are installed “, commented M. Grangent and M. Durand after studying the bridge.

The architecture of the bridge itself is designed as a number of arches constructed to allow the water to flow along the aqueduct above the bridge towards the town and thus cross the rivers Gardon or Gard.  The construction had to be very strong and solid to span the river, which had very irregular currents and violent spates.  This is the reason why the piles of the bridge were built in the shape of the hull of a ship, to better cut through the current.

Still today, in the 21st century, even after violent floods and the river in spate, when the water reached up to three quarters of the level of the lower arches, around 20 meters high, the bridge survived and did not suffer any damage.

The total length of the upper part, where the water flows on the third level, is 490 meters long.  This third level therefore supports the channel which is in turn supported by 47 arches, each 4 m 80 cm wide.   The difference in level is only 12 metres, namely an average incline of 24 cm/km, or 2.4 mm/meter.

The first and second levels of the bridge have respectively six and eleven large arches, their length varying between 15,5 meters and 24,5 meters.  The total difference in levelof the aqueduct is 17 meters for the 50 kilometers from the source to the city, passing via the bridge.

2500 years ago the Roman constructors developed such know-how that they built aqueducts of such a size that they still do not fail to surprise us in the 21st century:  the longest aqueduct of Roman times is the one in Carthage of 132 km,and one in Cologne of 95.5 km. In Gaule, two in the Lyons area, at Gier, 75 km,and at Brévenne, 60 km.  The one in Eygalières in Arles is 51 km, in Fréjus andTrasley in Bourges, 42.5 km.

The 12 upper arches were partly destroyed in the Middle Ages, and it was not until the 19th century that the Emperor Napoleon 111, an amateur archaeologist, had the bridge restored, returning it to its original appearance.  The monument was once again the object of important renovations.  Between 1842 and 1846 Charles-August Questel created a staircase in the interior of the last arch, in one of the piles with access to the channel.  From 1855 to 1859, important renovations took place, under the management of Jean-Charles Laisné.

 

Le Pont du Gard and the Route d’Uzès

Roman aqueduct, built on the river “Le Gardon”, during the reign of Agrippa,  son-in-law of Augustus, to take water to Nimes.

269 m in length by around 50m. height.

3 levels of arches, the first made of 6 arches, the second of 11 the third of 35.

A very picturesque tourist area, between Nîmes and Avignon.

Le Pont du Gard as it is nowadays

 

“There is not a monument from Roman times the sight of which surprises and troubles one to the same extent.  You see it suddenly, on a bend in the road, elegant and majestic, framed by the sky, and framing with its arches the graceful scenery of the stream and the hills”

— A great admirer of the bridge

 

In 2000, the French Finance Ministry, under the auspices of  “Great National Monuments” with the help of local authorities, Unesco  and the European Union, launched a development project for the site,  entrusted to the architect Jean-Paul Viguier, to ensure the preservation of this exceptional monument.

Léonce Reynaud, Traité d'Architecture, 1870 Image Gallica / BnF

Léonce Reynaud, Traité d’Architecture, 1870
Image Gallica / BnF

Le Pont de Roquefavour

It is inconceivable to tell the story of the Pont du Gard without mentioning “the modern copy” from the beginning of the 19th century, le Pont de Roquefavour.

The young architect, Lucas Monsaingeon, named the RMH Prize winner of 2016, made a detailed study of this bridge, and of course some of the references which follow struck a chord with him.

Marseille was still, at the beginning of the 19th Century, supplied by water by the rivers Huveaune and Jarret, which had historically supplied drinking water. The rate of flow became insufficient, posing problems of hygienewhich could encourage such epidemics as cholera.

It is in this context that Marseille hoped to bringone of its old dreams to reality, which has seen utopian projects and personal initiatives followed since the 16th century without success : to fetch water from the River Durance more than 80 km away.   The plan reckoned on taking water from the Durance at the level of the Pertuis Bridge, and taking it to Marseille by a channel 100 km long, of which 10,234 metres would be underground, and which would include four aqueducts.

In 1838 the definitive project was adopted and entrusted to the young engineer for Roads and Bridges, Franz Mayor de Montricher (a charismatic engineer who profoundly influenced the city of Marseille) and to William Fraisse.   It necessitated 15 years of work inspired by the ancient “Pont du Gard”.

L’aqueduc de Roquefavour
Photo © Florent Ruyssen 2011

The final choice of an aqueduct bridge was led by several parameters, explained Lucas Monsaingeon :

  • Technique – the cast iron pipes did not seem tested enough to withstand high pressure;
  • Personnel – Montricher always seemed driven by his pride to erect something which would be his masterpiece; and lastly
  • Prestige – because the Marseille Mayor’s office was keen to achieve a monumental work in the region.

Classified as a historic monument in 2002, the Roquefavour Bridge is today promoted to boast about the area’s merits, but in truth, the monument seems to have fallen into oblivion.  However Joseph Méry would write of Roquefavour :

Marseille wanted to supercede Rome, its sister, by its conquest of water. It built the indestructible Roquefavour aqueduct, inferior in grace but superior by the force of its du Gard style.

 * * *

The Gallo-Roman era, by the mastery of its elements, and guided by rules in respect of engineering, still dominates modern constructors.  The masterpiece of creative human genius and the skillfulness of Roman architects, aqueducts are a unique and exceptional testimony to this civilization, a remarkable example.

Text by Jacqueline Mainguy

English translation Jeannette Weston

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