Lo Scolmatore dell'Arno (The Arno floodway) is a artificial

flood control Flood management or flood control are methods used to reduce or prevent the detrimental effects of flood waters. Flooding can be caused by a mix of both natural processes, such as extreme weather upstream, and human changes to waterbodies and ru ...

channel of the river

Arno The Arno is a river in the Tuscany region of Italy. It is the most important river of central Italy after the Tiber. Source and route The river originates on Monte Falterona in the Casentino area of the Apennines, and initially takes a sou ...

from

Pontedera Pontedera (; ) is an Italian comune with a population of 30070, located in the province of Pisa, Tuscany, Central Italy, central Italy. The town is located 20 km (12 miles) from Pisa and 50 km (31 miles) from Florence. It houses the headquarte ...

to the

Ligurian Sea The Ligurian Sea is an arm of the Mediterranean Sea. It lies between the Italian Riviera ( Liguria) and the island of Corsica. The sea is thought to have been named after the ancient Ligures people. Geography The sea borders Italy as far as ...

at Calambrone. As a consequence of the Arno flood of 1949, it was decided to start the construction of ''Scolmatore dell'Arno'' in 1954 at a cost of more than 10 billion lire of the time. The work was not completed in time for the disastrous flood of 1966 that, in addition to Florence, caused enormous damages in Pontedera and

Pisa Pisa ( ; ) is a city and ''comune'' (municipality) in Tuscany, Central Italy, straddling the Arno just before it empties into the Ligurian Sea. It is the capital city of the Province of Pisa. Although Pisa is known worldwide for the Leaning Tow ...

. The floodway branches off the Arno 40 km from the river mouth ( off the coast), just downstream Pontedera in a southwesterly direction, where the Arno proper continues towards northwest. The elevation at the

bifurcation Bifurcation or bifurcated may refer to: Science and technology * Bifurcation theory, the study of sudden changes in dynamical systems ** Bifurcation, of an incompressible flow, modeled by squeeze mapping the fluid flow * River bifurcation, the for ...

is , with the floodway's main ingate controlled by four gates that during normal water levels are closed, whereas a secondary and smaller ingate has free flow. The main channel has a total length of and after a bend downstream it continues almost straight towards the sea in a west-southwest direction. The lower forms the border between the

province A province is an administrative division within a country or sovereign state, state. The term derives from the ancient Roman , which was the major territorial and administrative unit of the Roman Empire, Roman Empire's territorial possessions ou ...

s of

Livorno Livorno () is a port city on the Ligurian Sea on the western coast of the Tuscany region of Italy. It is the capital of the Province of Livorno, having a population of 152,916 residents as of 2025. It is traditionally known in English as Leghorn ...

and

, and the mouth is situated between Calambrone and the

seaport A port is a maritime facility comprising one or more wharves or loading areas, where ships load and discharge cargo and passengers. Although usually situated on a sea coast or estuary, ports can also be found far inland, such as Hamburg, Manc ...

, south of Arno proper's mouth. Scolmatore dell'Arno has a few branches, most notably is the much older

Navicelli channel The Navicelli Channel is a channel built between 1563 and 1575 to connect Pisa with the port of Livorno. The name originates from the so-called ''navicelli'', small sized Tuscany, Tuscan boats that transported goods on the channel across the Pisan ...

that connects less than one km from the mouth, although they lie parallel for further before this channel turns towards northwest. Another few channels drain the area between Arno proper and the floodway. The main

tributary A tributary, or an ''affluent'', is a stream or river that flows into a larger stream (''main stem'' or ''"parent"''), river, or a lake. A tributary does not flow directly into a sea or ocean. Tributaries, and the main stem river into which they ...

is the

River Tora The Tora is a stream in the province of Livorno, Tuscany, central Italy. It is a stretch of water from below Pisan Hills, south of the Arno Valley. With its 29 kilometres it is the longest river that receives most of its tributaries from Livorno H ...

that converges from the mouth, just northwest of

Mortaiolo Mortaiolo is a hamlet in the comune of Collesalvetti (province of Livorno, Italy), located near Vicarello, Collesalvetti, Vicarello. The village, which has about 150 inhabitants, is located in a flat triangle between two rivers: the Scolmatore d ...

. A minor tributary is the River Zannone that converges from the mouth, just downstream the aforementioned bend of the channel. It is likely that the lower part of the channel at least partly occupies the original paths of Tora and Zannone. Both these rivers originates from the Pisan hills south of the Arno valley and the channel itself. The floodway was designed for a capacity of per second, which should handle 60% of the water flowing through Pisa, but this magnitude was never achieved and due to lack of maintenance the actual drainage of the channel is not more than per second. A related problem is

silt Silt is granular material of a size between sand and clay and composed mostly of broken grains of quartz. Silt may occur as a soil (often mixed with sand or clay) or as sediment mixed in suspension (chemistry), suspension with water. Silt usually ...

deposits of the

that lies adjacent to the floodway's mouth.

Plans for future navigability of the channel

There is an ongoing project to improve the navigability of the channel, intended exclusively for freight, excluding the use of tourist boating on the channel. The navigability is developed to promote the connection between the dock in the port of Livorno and commercial activities at Guasticce and Vicarello, upstream at a distance of . It will use the current channel's connection to the port of Livorno, primarily through excavation of the channel to ensure a width of about and a depth of at least , so as to allow the passage of boats and barges larger to the present. The project also includes the raising of the deck of the bridge of the Aurelia road (by Stagno) and the construction of docks for loading and unloading of goods at Guasticce and Vicarello.

References

{{Coord, 43, 40, 06, N, 10, 37, 17, E, region:IT_type:landmark_source:kolossus-itwiki, display=title Buildings and structures in the Province of Pisa Canals in Italy Pontedera