The balancing of incoming and outgoing water allows the
Canal du Midi
The Canal du Midi (; ) is a long canal in Southern France (). Originally named the ''Canal Royal en Languedoc'' (Royal Canal in Languedoc) and renamed by French revolutionaries to ''Canal du Midi'' in 1789, the canal is considered one of the g ...
to operate as it does. Each time a lock operates, large quantities of water are either required to fill it or dump from it into the lower level
pound. There must be a constant source of water in order to fill and the excess water dumped must have a place to exit the canal without it overflowing. Being able to provide this water source was one of the most important problems to be solved by
Pierre Paul Riquet, its creator.
In the canal's original configuration of 1687, water was provided by the
Rigole de la plaine from the
River Sor and from the
Bassin de Saint-Ferréol. The
Bassin de Lampy was added later. Since the drought of 1989–1990, water can also be made available from the
Lac de Montbel.
Water leaving the canal between locks, will exit through either a
weir
A weir or low-head dam is a barrier across the width of a river that alters the flow characteristics of water and usually results in a change in the height of the water level. Weirs are also used to control the flow of water for outlets of l ...
() or a
siphon
A siphon (; also spelled syphon) is any of a wide variety of devices that involve the flow of liquids through tubes. In a narrower sense, the word refers particularly to a tube in an inverted "U" shape, which causes a liquid to flow upward, abo ...
(). Leaving through the
weir
A weir or low-head dam is a barrier across the width of a river that alters the flow characteristics of water and usually results in a change in the height of the water level. Weirs are also used to control the flow of water for outlets of l ...
, the water simply flows over the side of the canal via a stone or concrete ledge. If the water reaches a specific level, it may be siphoned off via a stone
siphon
A siphon (; also spelled syphon) is any of a wide variety of devices that involve the flow of liquids through tubes. In a narrower sense, the word refers particularly to a tube in an inverted "U" shape, which causes a liquid to flow upward, abo ...
.
See also
*
Aqueducts on the Canal du Midi
*
Canal du Midi
The Canal du Midi (; ) is a long canal in Southern France (). Originally named the ''Canal Royal en Languedoc'' (Royal Canal in Languedoc) and renamed by French revolutionaries to ''Canal du Midi'' in 1789, the canal is considered one of the g ...
*
Locks on the Canal du Midi
Notes
: Distance in km from the beginning of the canal in
Toulouse
Toulouse (, ; ; ) is a city in southern France, the Prefectures in France, prefecture of the Haute-Garonne department and of the Occitania (administrative region), Occitania region. The city is on the banks of the Garonne, River Garonne, from ...
.
References
{{Reflist
External links
CanalMidi.comThe Canal du Midi - "Seuil de Naurouze"
Canal du Midi