Montech water slope
Encyclopedia
The Montech water slope is a type of canal inclined plane
built on the Canal de Garonne
, in the commune of Montech
, Tarn-et-Garonne
, South West France
. It is managed by the publicly-owned Voies navigables de France and it replaced a group of five successive locks.
is based on a sloping channel up or down which a wedge of water retained by a water tight gate is moved. This technique was invented in the 19th century by the German engineer Julius Greve and described by the French engineer Jean Aubert
in 1961. The Montech water slope was inaugurated in July 1974.
A sloping concrete channel is continuously fed by a small stream of water. A movable gate spans the channel. The points of contact of the gate with the channel are tight but not fixed. Two adapted diesel locomotives, one on either side of the channel support the gate.
To allow a boat to ascend: the gate is lifted, the boat enters the channel, and then the gate is lowered. This isolates the wedge of water, on which the boat is floating, from the canal it has left. The locomotives ascend the slope pushing the water wedge in front of the movable gate. The boat rides on the water wedge.
Animation - Click on « comment ça marche » (or go directly to the animation)
Each diesel electric locomotive develops 1000 hp distributed to four drive motors, one on each of the four axles each with two large pneumatic tyres.
The three contact faces of the gate with the channel are equipped with seals to keep the wedge of water in place. The gate is raised or lowered using a hydraulic ram.
The shock absorber is a hydraulically-levelled hinged metal frame. It allows boats to be moored to the gate during ascents and descents. An electronic system keeps motion gentle and smooth. Finally triple brakes slow the system without jerks.
Canal inclined plane
An inclined plane is a system used on some canals for raising boats between different water levels. Boats may be conveyed afloat, in caissons, or may be carried in cradles or slings. It can be considered as a specialised type of cable railway....
built on the Canal de Garonne
Canal de Garonne
The Canal de Garonne, formerly known as Canal latéral à la Garonne, is a French canal dating from the 19th century which connects Toulouse to Castets-en-Dorthe. The remainder of the route to Bordeaux uses the Garonne River. It is the continuation of the Canal du Midi which connects the...
, in the commune of Montech
Montech
Montech is a commune in the Tarn-et-Garonne department in the Midi-Pyrénées region in southern France.-References:*...
, Tarn-et-Garonne
Tarn-et-Garonne
Tarn-et-Garonne is a French department in the southwest of France. It is traversed by the Rivers Tarn and Garonne, from which it takes its name.-History:...
, South West France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
. It is managed by the publicly-owned Voies navigables de France and it replaced a group of five successive locks.
Operating Principles
The principle of the water slopeWater slope
A water slope is a type of canal inclined plane built to carry boats from a canal or river at one elevation up to or down to a canal or river at another elevation.-Operation:...
is based on a sloping channel up or down which a wedge of water retained by a water tight gate is moved. This technique was invented in the 19th century by the German engineer Julius Greve and described by the French engineer Jean Aubert
Jean Aubert (engineer)
Jean Aubert was a French engineer. In 1961 he used the idea of the German engineer Julius Greve from the last century to describe a pente d'eau, which was a way of moving boats up the gradient of a canal without locks. The design consisted of a sloping channel through which a wedge of water on...
in 1961. The Montech water slope was inaugurated in July 1974.
A sloping concrete channel is continuously fed by a small stream of water. A movable gate spans the channel. The points of contact of the gate with the channel are tight but not fixed. Two adapted diesel locomotives, one on either side of the channel support the gate.
To allow a boat to ascend: the gate is lifted, the boat enters the channel, and then the gate is lowered. This isolates the wedge of water, on which the boat is floating, from the canal it has left. The locomotives ascend the slope pushing the water wedge in front of the movable gate. The boat rides on the water wedge.
Animation - Click on « comment ça marche » (or go directly to the animation)
Details of the machinery
By its power and ingenuity the slope engine is the key to the system. It consists of:- The two locomotives rigidly connected together by a cross piece which spans the channel with the locomotives travelling on the channel's banks.
- The gate acts as a big valve connected to the rigid cross member by an arm.
- A horizontal beam serving as a shock absorber between the boats and the gate.
Each diesel electric locomotive develops 1000 hp distributed to four drive motors, one on each of the four axles each with two large pneumatic tyres.
The three contact faces of the gate with the channel are equipped with seals to keep the wedge of water in place. The gate is raised or lowered using a hydraulic ram.
The shock absorber is a hydraulically-levelled hinged metal frame. It allows boats to be moored to the gate during ascents and descents. An electronic system keeps motion gentle and smooth. Finally triple brakes slow the system without jerks.
Benefits
The water slope allows the five locks it replaced to be bypassed. These locks are still in use, mainly to allow the passage of pleasure boats. The water slope is reserved for boats 30 to 40m in length and ascends or descends in 20 minutes, 45 minutes faster than the passage of the five locks.Design features
- Weight of the engines: 200 tonnes
- Pushing effort: 60 tonnes
- Speed : 4.5 km/h
- Volume of water moved : 1,500 m³
- Slope of the channel : 3 %
- Height of the slope: 13.30 m
- Depth of water wedge moved: 3.75 m
- Length of the water wedge : 125 metres
- Power of the locomotives: 2 x 1000 HP
- Length of the channel: 443 m
- Width of the channel: 6 m
- Duration of passage: about 6 minutes
- Length, width and capacity of the boats : 38.5m, 5.5m and 250 tonnes.
See also
- Fonserannes water slopeFonserannes water slopeThe Fonserannes Water Slope, is a disused inclined plane on the Canal du Midi parallel to the Fonserannes Lock. It has a rise of and a slope of five degrees.This technique for a water slope was described by the French engineer Jean Aubert in 1961....
- GaronneGaronneThe Garonne is a river in southwest France and northern Spain, with a length of .-Source:The Garonne's headwaters are to be found in the Aran Valley in the Pyrenees, though three different locations have been proposed as the true source: the Uelh deth Garona at Plan de Beret , the Ratera-Saboredo...
- Canal du MidiCanal du MidiThe is a long canal in Southern France . The canal connects the Garonne River to the on the Mediterranean and along with the Canal de Garonne forms the Canal des Deux Mers joining the Atlantic to the Mediterranean. The canal runs from the city of Toulouse down to the Étang de Thau...
- Original French article from which this article was translated