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Po (river)

Coordinates:44°57′9″N12°25′55″E/ 44.95250°N 12.43194°E/44.95250; 12.43194
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This article is about the Italian river. For other uses, seePo.
Po
The Po inTurin,Piedmont
Map of the Po watershed
Location
CountryItaly, France and Switzerland
Po BasinItaly, Switzerland, France
CitiesTurin,Cremona,Piacenza,Ferrara
Physical characteristics
SourceMonte Viso
• locationNearCrissolo, Piedmont,Italy
• coordinates44°42′5″N7°5′35″E/ 44.70139°N 7.09306°E/44.70139; 7.09306
• elevation3,700 m (12,100 ft)
MouthAdriatic Sea
• location
NearAdria, Veneto,Italy
• coordinates
44°57′9″N12°25′55″E/ 44.95250°N 12.43194°E/44.95250; 12.43194
• elevation
0 m (0 ft)
Length652 km (405 mi)
Basin size74,000 km2(29,000 sq mi)
Discharge
• average1,540 m3/s (54,000 cu ft/s)
• maximum3,100 m3/s (110,000 cu ft/s)
Basin features
Tributaries
• leftDora Baltea,Ticino,Adda,Oglio,Mincio
• rightTanaro
[1][2]

ThePo(/poʊ/POH,Italian:[ˈpɔ])[3]is the longest river in Italy. It flows eastward across northern Italy, starting from theCottian Alps.The river's length is either 652 km (405 mi) or 682 km (424 mi), if theMaira,a right bank tributary, is included. Theheadwatersof the Po are formed by aspringseeping from a stony hillside at Pian del Re, a flat place at the head of theVal Pounder the northwest face ofMonviso.The Po then extends along the45th parallel northbefore ending at a delta projecting into theAdriatic SeanearVenice.

It is characterized by its largedischarge(severalrivers over 1,000 kmhave a discharge inferior or equal to the Po). It is, with theRhôneandNile,one of the three Mediterranean rivers with the largest water discharge.[4]As a result of its characteristics, the river is subject to heavy flooding. Consequently, over half its length is controlled withembankments.[1]

The river flows through many important Italian cities, includingTurin,Piacenza,CremonaandFerrara.It is connected toMilanthrough a net ofchannelscallednavigli,whichLeonardo da Vincihelped design. Near the end of its course, it creates a widedelta(with hundreds of small channels and five main ones, calledPo di Maestra,Po della Pila,Po delle Tolle,Po di GnoccaandPo di Goro) at the southern part of which isComacchio,an area famous foreels.ThePo Valleywas the territory of RomanCisalpine Gaul,divided into Cispadane Gaul (south of the Po) and Transpadane Gaul (north of the Po).

Geography

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The Po has a drainage area of 74,000 km2in all, 70,000 of those being in Italy, of which 41,000 is inmontaneenvironments and 29,000 on the plain.[2]The slope of the Po's river valley decreases from 0.35% in the west to 0.14% in the east, a low gradient. Along its path lie 450 standing lakes.[2]Almost all of the rest of the non-Italy basin is inSwitzerland,primarily in thecanton of Ticino,which is essentially drained by the riverTicinorising in theGotthard Area,and includesLake MaggioreandLake Lugano.A small part of thecanton of Grisonsdrains to the Po, partly via the Ticino. TheSimplon Valleyin thecanton of Valaisis drained by theDiveria.[5] A minute section of the Po basin belongs toFrancein theVallée Étroite[it;fr](literally, the Narrow Valley) running fromMont Thaborto the Italian ski resort ofBardonecchia.although in France, Vallée Étroite is so remote it is essentially administered by Italy (telephone network, rubbish collections, etc.[6]). Further minuscule parts of the Po's basin (measurable in the hundreds of metres of linear distance) within France are found in the form of small streamheads forced into France by the1947 Peace Treaty of Parisas a punitive measure against Italy. These can be found on theMont Cenisand Mongenevre passes. The former contains a reservoir dammed at the Po end and so technically constitutes part of its basin, although it contributes little to the water flow as the water is, by definition, retained by the dam. The Po is the longest river in Italy; at its widest point it is 503 m (1,650 ft) across.[1]

Po Valley

[edit]
Main article:Po Valley

The vast valley around the Po is called the Po Basin orPo Valley(ItalianPianura PadanaorVal Padana); the main industrial area and the largest agricultural area in the country - accounting for 35% of Italianagricultural production.[7]In 2002, more than 16 million people lived in the area, at the time nearly one-third of the population of Italy.[1]

The two main economic uses of the valley are for industry and for agriculture. The industrial centres, such asTurinand Milan, are located on higher terrain, away from the river. They rely for power on the numeroushydroelectricstations in or on the flanks of the Alps, and on the coal/oil power stations which use the water of the Po basin as coolant. Drainage from the north is mediated through several large, scenic lakes, commonly referred to as theItalian Lakes,and shared with Switzerland. The streams are now controlled by so many dams as to slow the river'ssedimentationrate, causing geologic problems. The expansive, moist and fertileflood plainis reserved mainly for agriculture and is subject toflash floods,even though the overall quantity of water is lower than in the past and lower than demand. The main products of the farms around the river arecerealsincluding – unusually for Europe –rice,which requires heavyirrigation.The latter method is the chief consumer of surface water, while industrial and human consumption use underground water.

Tributaries

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The Po has 141tributaries.[1]They include (R on the right bank, L on the left, lookingdownstream):

TheReno(R) was a tributary of the Po until the middle of the eighteenth century when the course was diverted to lessen the risk of devastating floods. TheTanarois about 50 km (31 mi) longer than the upper Po at their confluence nearAlessandria.

The longest tributaries of the Po areAdda(313 km),Oglio(280 km),Tanaro(276 km) andTicino(248 km).

Po Delta

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Protected areas

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Flamingoes in the Po Delta Regional Park.

The Po Delta wetlands have been protected by the institution of two regional parks in theregionsin which it is situated:VenetoandEmilia-Romagna.The Po Delta Regional Park in Emilia-Romagna, the largest, consists of four parcels of land on the right bank of the Po and to the south. Created by law in 1988, it was managed by a consortium, theConsorzio per la gestione del Parco,to whichFerraraandRavennaprovinces belong as well as ninecomuni:Comacchio,Argenta,Ostellato,Goro,Mesola,Codigoro,Ravenna,Alfonsine,andCervia.Executive authority resided in an assembly of the presidents of the provinces, the mayors of the comuni and the board of directors. They employed a Technical-Scientific Committee and a Park Council to carry out directives. In 1999 the park was designated aWorld Heritage SitebyUNESCOand was added to "Ferrara, City of the Renaissance, and its Po Delta."[8]From 2012 the park is managed by theEnte di Gestione per i Parchi e la Biodiversità - Delta del Po,composed by thecomuniof Alfonsine, Argenta, Cervia, Codigoro, Comacchio, Goro, Mesola, Ostellato and Ravenna.[9]The 53,653 ha (132,580 acres) of the park contain wetlands, forest, dunes and salt pans. It has a highbiodiversity,with 1,000–1,100 plant species and 374 vertebrate species, of which 300 are birds.[10]

Active delta

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The most recent part of the delta, which projects into theAdriaticbetweenChioggiaandComacchio,contains channels that connect to the Adriatic and therefore is called the active delta by the park authorities, whereas the fossil delta contains channels that no longer connect the Po to the Adriatic (but once did). The active delta was created in 1604 when the city ofVenicediverted the main stream, thePo grandeorPo di Venezia,from its channel north ofPorto Viroto the south of Porto Viro in a channel then called theTaglio di Porto Viro,"Porto Viro cut-off". Their intent was to stop the gradual migration of the Po toward the lagoon of Venice, which would have filled up with sediment had contact been made. The subsequent town ofTaglio di Pogrew around the diversionary works. The lock ofVolta Grimanablocked the old channel, now thePo di Levante,which flows to the Adriatic through Porto Levante.[11]

BelowTaglio di PotheParco Regionale Veneto,one of the tracts under the authority of theParco Delta del Po,contains the latest branches of the Po. ThePo di Gnoccabranches to the south followed by thePo di Maestrato the north atPorto Tolle.At Tolle downstream thePo di Veneziadivides into thePo delle Tolleto the south and thePo della Pilato the north. The former exits at Bonelli. The latter divides again at Pila into theBusa di Tramontanato the north and theBusa di Sciroccoto the south, while the mainstream, theBusa Dritta,entersPunta Maistraand exits finally past Pila lighthouse.

Despite the park administration's definition of the active delta as beginning at Porto Viro, there is another active channel upstream from it at Santa Maria in Punta, where theFiume Podivides into thePo di Goroand thePo di Venezia.

Fossil delta

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The fossil Po is the region of no longer active channels from the Po to the sea. It begins upstream fromFerrara.TheFiume Pocurrently flowing to the north of Ferrara is the result of a diversion atFicaroloin 1152 made in the hope of relieving flooding in the vicinity ofRavenna.The diversion channel was at first called thePo di Ficarolo.TheFiume Pobefore then followed thePo di Volano,no longer connected to the Po, which ran to the south of Ferrara and exited nearVolano.In Roman times it did not exit there but ran to the south as thePadus Vetus( "old Po" ) exiting nearComacchio,from which split thePo di Primaroexiting close toRavenna.[12]

Before 1152 the seaward extension of today's delta, about 12 km (7.5 mi), did not exist. The entire region from Ravenna to Chioggia was dense swamps, explaining why theVia Aemiliawas constructed betweenRiminiandPiacenzaand did not begin further north.

Geologic history

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TheMediterranean Basinis a depression in theEarth's crust caused by theAfrican Plateslipping under theEurasian Plate.Typically in geologic history the depression is filled with sea water under various geologic names such asTethys Sea.In the last period of theMioceneEpoch, theMessinian(7–5mya), theMessinian salinity crisis,a near drying of the Mediterranean, was caused by the sea level dropping below the sill at theStrait of Gibraltarand theequilibriumbetween evaporation and replenishment shifting in favor of evaporation. At that time the Po Valley and theAdriaticdepression were a singlecanyonsystem thousands of feet deep. On the southwest theApennine Mountainsbordered a land mass termed Tyrrhenis geologically. Theirorogenywas just being completed in the Miocene. On the north theAlpine Orogenyhad already created theAlps.

At the end of the Messinian the ocean broke through the sill and the Mediterranean refilled. The Adriatic transgressed into all of northern Italy. In the subsequentPliocenesedimentary outwash primarily from the Apennines filled the valley and the centralAdriaticgenerally to a depth of 1,000 m (3,300 ft) to 2,000 m (6,600 ft) but from 2,000 m (6,600 ft) to 3,000 m (9,800 ft) off the current mouth of the Po, with pockets as deep as 6,000 m (20,000 ft). At the start of thePleistocenethe valley was full. Cycles oftransgressionand regression are detectable in the valley and the Adriatic as far as its centre and in the southern Adriatic.

From the Pleistocene alternation of maritime and alluvial sediments occur as far west asPiacenza.The exact sequences at various locations have been studied extensively. Apparently the sea advanced and receded over the valley in conformance to an equilibrium between sedimentation and glacial advance or recession at 100,000-year intervals and 100 m (330 ft) to 120 m (390 ft) fluctuation of sea level. An advance began after theLast Glacial Maximumaround 20,000 years ago, which brought the Adriatic to a high point at about 5,500 years ago.[13]

Since then the Podeltahad beenprograding.The rate of coastal zone progradation between 1000 BC and 1200 AD was 4 m/yr.[14]Human factors, however, brought about a change in the equilibrium in the mid-20th century with the result that the entire coastline of the northern Adriatic is now degrading.Venice,which was originally built on islands off the coast, is most at risk due to subsidence, but the effect is realized in the Po delta as well. The causes are first a decrease in the sedimentation rate due to the locking of sediment behind hydroelectric dams and the deliberate excavation of sand from rivers for industrial purposes. Second, agricultural use of the river is heavy; during peak consumption the flow in places nearly dries up, causing local contention. As a result of decreased flow, salt water is intruding into theaquifersand coastal ground water.Eutrophicationin standing waters and streams of low flow is on the increase.[15]The valley is subsiding due to the extraction of ground water.[2]

Human impacts

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Pollution

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Always prone to fog, the valley is subject to heavy smog due to industrial atmospheric emissions, especially fromTurin.[16]

The city of Milan had no sewage treatment plants. Sewage went through channels directly into the Po, for which theEuropean Environment Agencycited the city.[1]Since 2005, all sewage from Milan is treated in plants at Nosedo, San Rocco and Peschiera Borromeo. These treat the sewage from over 2.5 million inhabitants.[17]

In 2005, water from the Po was found to contain muchbenzoylecgonine,passedbycocaineusers inurine.Based on these figures, cocaine consumption was estimated to be about 4 kg daily, or 27 doses per day per thousand young adults in thedrainage basin– nearly three times higher than estimated.[18]

On February 24, 2010, the Po was contaminated by anoil spillcoming from a refinery inVillasantathrough theLambro,theAgenzia Nazionale Stampa Associatanews agency has estimated it to be about 600,000 liters.[19][20]

Water resource management

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The Po inSan Mauro Torinesein July 2012.

Until 1989 water resources were administered regionally or locally. The major authority on the lower Po was theMagistrato alle Acque di Venezia,first formed in the 16th-centuryRepublic of Venice.It made all the decisions concerning the diversion of the lower river. Most part of the delta is still inVeneto.

In 1907 under theKingdom of Italythe agency became theMagistrato alle Acqueand took responsibility for all the water resources in northeastern Italy. Currently it is a decentralized institution of the Ministry of Public Works, headed by a chairman appointed by the Head of State and the Council of Ministers. Its headquarters are in Venice. Its domain is the management and protection of the water system inVeneto,Mantua,Trento,BolzanoandFriuli-Venezia Giulia.

In 1989 in response to the major geologic problems that were developing along the river Law no. 183/89 was passed authorizing The Po Basin Water Board (Autorità di bacino del fiume Po), which would direct operations concerning all the water resources in the Po basin (see underPo Valley). Its headquarters have been inParmasince its inception in 1990. It considers itself a synergy among all the institutions concerned with the preservation and development of the Po basin. It is administered by officials chosen from the administrations of the constituent regions and provinces.[21]

Green trees in the top half of the image have hanging branches, and the lower half shows vining, elephant-ear-shaped leaves.
Protected ecological rebalancing area on the Stellata in Mesola and Cavo Napoleonico

In 2009 the water board began its Integrated River Basin Management Plan to meet theEuropean Union(EU)Water Framework Directive,2000/60/EC.[22]This takes in water management and flood risk plans antecedent. Between 2009 and 2015 the Po Valley Project (the implementation of the plan) took more than 60 measures, notably to: heighten and strengthenlevees,increaseflood-meadows,resume natural sediment transport and deposition points, enlarge wetlands, afforest, re-nature, promote biodiversity and recreational use.[23]

[edit]

InRomantimes the waterway was navigable as far upstream asTurin.[24][25]Today the waterway is navigable for substantial craft (up to 1350tonnes—theEuropean Class IV waterway standard) fromCremonato the river delta on theAdriatic.Passage by smaller vessels is available for some distance above Cremona. In the lower reaches the surrounding basin is generally flat and it is served by a complicated network of small canals linked to the river.[26]However, transit is severely hampered during summer months by low water levels.[27][28]

Dams

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At the village ofIsola Serafiniin thecomuneofMonticelli d'Ongina,Piacenza Province,40 km (25 mi) downstream from Piacenza, a 362 m (1,188 ft) long, 20 m (66 ft) high gate dam featuring eleven 30 m (98 ft) openings gated by vertical lift gates, crosses the Po. Nine gates are 6.5 m (21 ft) high and two are 8 m (26 ft) high for sediment-scouring purposes. A spillway to the right passes through a hydroelectric station of 4 generators of 76 MW each operated by a 3.5–11 m (11–36 ft) head of water. The spillway connects to a diversionary canal subtending a 12 km (7.5 mi) loop of the Po. A ship lock 85 m (279 ft) long and 12 m (39 ft) wide next to the station passes some traffic through the canal, but above the dam traffic is mainly barges. The average flow at the dam is 854 m3/s, with a 12,800 m3/s maximum.[29]

Drought

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The historic average flow for June is 1,805 cubic metres per second. In late June 2022, the flow measured inFerrarafell below an average of 145 cubic metres per second.Climate changehas caused several droughts across Northern Italy, with predictions for their frequency and the severity, resulting in a "decrease in precipitation during critical crop growing seasons".[7]In July 2022, the Italian government declared a state of emergency in the regions Emilia-Romagna, Lombardy, Piedmont, Veneto and Friuli-Venezia Giulia.[24]Water levels decreased and revealed large riverbed areas and lost objects.[30]

Cultural history

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The Po is first certainly identified in the Graeco-Roman historians and geographers of the lateRoman Republicand the earlyRoman Empire,long after the valley had been occupied successively by prehistoric and historic peoples:Ligures,Etruscans,Celts,Veneti,Umbri,and Romans. At that late date, the ancient authors were attempting to explain the provenance of the name. Perhaps the earliest of these,Polybius[31](2nd century BC), usesPados(in Greek) and says that it was to be identified with theEridanosof the poets. Moreover, the country people call itBodencus.

This implies that a "country" population either remained from prehistoric times or adopted the name in use by that substrate. The name has been segmented asBod-encusorBod-incus,the suffix being characteristic of the ancientLigurian languageof northern Italy, southern France,Corsicaand elsewhere.[32]

Pliny the Elderhas the most to say about thePadusof his times.Herodotushad expressed doubt concerning the existence of a river in Europe,Eridanos,which flowed into the northern sea, he said, from whichambercame.[33]He believed it was a Greek name (there are other Eridanos rivers in Greece), "invented by some poet," but makes no conjectures as to where it might be. Pliny points out that in his own time the Eridanos had become wrongly identified with thePadus.He does not know when or how, but like Herodotus, he blames the poets.[34]Amber is supposed to have come from there.Phaëthon,son of the sun, struck by lightning changed into poplars and exuded tears every year, which is the source of amber (a myth ofPausanias). Expressing surprise at the ignorance of the poets, Pliny says "There can be no doubt that amber is the product of the islands of the northern ocean (Baltic Sea) "and attributes its introduction into the Po Valley to theVeneti,the last link in a trade route to the north throughPannonia.

Pliny (Hist. Nat.,iii. 122) also gives the Ligurian name of the Po asBodincus,which he translates as "bottomless". The rootbod-has been generally analyzed as containing thePIEbase *bhu(n)d(h)- seen inSanskritbudhnahandAvestanbuna- "bottom",Greekpythmen"foundation",Latinfundus"bottom",Old Irishbond"sole of the foot". The wordBodincusappears in theplace nameBodincomagus,aLiguriantown on the right bank of the Po downstream from today's Turin. The Po, along with other rivers innorthern Italy,was the scene of numerous military episodes throughout theMiddle Agesand all the major cities and coastal lordships were equipped with real river fleets. Particularly violent were the clashes between the naval squads of theGhibellinemunicipalities (CremonaandPavia) and those of the municipalities of theLombard leagueduring the thirteenth century and between the Venetian fleet and that of theDuchy of Milanin the fifteenth century.[35]

Mythology

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The Po is often identified with theEridanosor Eridanus river ofGreek mythology.This mythical river is the namesake of theconstellation Eridanus.

See also

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References

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  1. ^abcdefZwingle, Erla (May 2002)."Italy's Po River Punished for centuries by destructive floods, northern Italians stubbornly embrace their nation's longest river, which nurtures rice fields, vineyards, fisheries—and legends".National Geographic.Archived fromthe originalon December 23, 2007.Retrieved6 April2009.
  2. ^abcdRaggi, Meri; Davide Ronchi; Laura Sardonini; Davide Viaggi (2007)."Po Basin Case study status report"(PDF).AquaMoney.Retrieved6 April2009.[permanent dead link]
  3. ^Latin:PadusorĒridanus;Ancient Ligurian:BodincusorBodencus
  4. ^Margat, Jean F. (2004).Mediterranean Basin Water Atlas.UNESCO.p. 4.ISBN9782951718159.There are few rivers with an abundant flow. Only three rivers have a mean discharge of more than 1000 m3/s: the Nile (at Aswan), the Rhône and the Po.
  5. ^"Gondo on the Swiss National Map".Federal Office of Topography.Retrieved15 March2022.
  6. ^Avondo, Gian Vittorio; Comello, Marco (2022).Frontiere contese tra Italia e Francia. 1947: le valli perdute del Piemonte(in Italian). Turin: Edizioni del Capricorno. p. 120.ISBN9788877076731.
  7. ^abBorzì, Iolanda; Monteleone, Beatrice; Bonaccorso, Brunella; Martina, Mario (2021-03-03)."Estimating the economic impacts of drought on agriculture through models and surveys in the Po river basin (Northern Italy)".Egu General Assembly Conference Abstracts.Bibcode:2021EGUGA..2312066B.doi:10.5194/egusphere-egu21-12066.S2CID235565127.
  8. ^"Carta d'identità".Parco Delta del Po: Emilia-Romagna. Archived fromthe originalon 23 April 2009.Retrieved14 April2009.
  9. ^"Chi siamo | Parco del Delta del Po".
  10. ^"Protected Area".Parco del Delta del Po.Retrieved14 April2009.
  11. ^"Active Delta and Fossil Delta".Parco Delta del Po Veneto. Archived fromthe originalon 21 June 2009.Retrieved15 April2009.
  12. ^Grove, Alfred Thomas; Oliver Rackham (2003).The Nature of Mediterranean Europe: An Ecological History(2, illustrated ed.). Yale University Press. p. 341.ISBN978-0-300-10055-6.
  13. ^McKinney, Frank Kenneth (2007). "Chapter 6: Pleistocene and Holocene Sediments".The northern Adriatic ecosystem: deep time in a shallow sea(illustrated ed.). Columbia University Press.ISBN978-0-231-13242-8.
  14. ^J.P.M. Syvitski; et al. (October 2005). "Distributary channels and their impact on sediment dispersal".Marine Geology.222–223 (15).Elsevier:75–94.Bibcode:2005MGeol.222...75S.doi:10.1016/j.margeo.2005.06.030.
  15. ^"Facing Water Challenges in the Po River Basin, Italy:A WWDR3 Case Study".waterwiki.net. 2009. Archived fromthe originalon 1 August 2009.Retrieved6 April2009.
  16. ^"Haze in the Po River Valley, Italy".NASA Earth Observatory. 2009.Retrieved6 April2009.
  17. ^Recchia, Roberto."Il quadro del sistema idrico del comune di Milano".Comune di Milano.Archived fromthe originalon 23 September 2015.Retrieved7 September2015.
  18. ^"Italian river 'full of cocaine'".BBC News.5 August 2005.Retrieved6 April2009.
  19. ^"Oil spill threatens Italy's Po River".CBC News. 24 February 2010.Retrieved24 February2010.
  20. ^Giari, L; Dezfuli, BS; Lanzoni, M; Castaldelli, G (2012). "The impact of an oil spill on organs of bream Abramis brama in the Po River".Ecotoxicology and Environmental Safety.77:18–27.doi:10.1016/j.ecoenv.2011.10.014.PMID22030380.[dead link]
  21. ^"L'Ente"(in Italian). Autorità di bacino del fiume Po. Archived fromthe originalon 20 April 2009.Retrieved5 June2009.
  22. ^"Elements of Good Practice in Integrated River Basin Management: A Practical Resource for implementing the EU Water Framework Directive"(PDF).Brussels, Belgium: WWF–World Wide Fund For Nature (formerly World Wildlife Fund). October 2001.Retrieved6 June2009.
  23. ^Bortone, Giuseppe (18 March 2009)."Po Basin (Italy)"(PDF).Istanbul: Autorità di Bacino del Fiume Po.Retrieved6 June2009.
  24. ^abJones, Tobias (2022-07-10)."Quiet flows the Po: the life and slow death of Italy's longest river".The Observer / The Guardian.Retrieved2022-07-14.
  25. ^Grimal, Pierre(1983).Roman cities = Les villes romaines.Translated by G. Michael Woloch. Madison, Wis.: University of Wisconsin Press. p. 273.ISBN0-299-08930-4.
  26. ^McNeil, Ian (1990). "Italy".An Encyclopaedia of the history of technology.London: Routledge.ISBN9781134981649.
  27. ^Ferreira, Rui M. L.; Alves, Elsa C. T. L.; Leal, Joao G. A. B.; Cardoso, Antonio H. (14 September 2006).River Flow 2006, Two Volume Set: Proceedings of the International Conference on Fluvial Hydraulics, Lisbon, Portugal, 6-8 September 2006.Taylor and Francis.p. 1973.ISBN9781439833865.Retrieved18 June2022.
  28. ^Giuffrida, Angela (17 June 2022)."'We worry about it disappearing': alarm grows over Italy's drought-hit Po River ".the Guardian.Retrieved18 June2022.
  29. ^Brunelli, A.; D. Caputo; F. Chillè; V. Maugliani (2003). "The bump of a boat into a gate-structure dam: An unusual risk scenario". In Llanos, JA; Yague, J. (eds.).Dam Maintenance and Rehabilitation: Proceedings of the International Congress on Conservation and Rehabilitation of Dams, Madrid, Spain, 11–13 November 2002(illustrated ed.). Taylor & Francis. pp. 145–146.ISBN978-90-5809-534-3.
  30. ^Kuta, Sarah."Drought in Italy Reveals Sunken World War II Barge".Smithsonian Magazine.
  31. ^Histories,II.16.
  32. ^Daiches, David; Anthony Thorlby (1972).Literature and western civilization(illustrated ed.). Aldus. p. 78.
  33. ^Histories,III.115.
  34. ^Historia Naturalis,Book 37, Chapter 11.
  35. ^Romanoni, Fabio (2023).La guerra d'acqua dolce. Navi e conflitti medievali nell'Italia settentrionale.Bologna: Clueb. pp. 76–82.ISBN978-88-31365-53-6.Retrieved26 April2023.

Further reading

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[edit]
Wikimedia Commons has media related toPo river.
Wikisourcehas the text of the1911Encyclopædia Britannicaarticle "Po".
Retrieved from "https://en.wikipedia.org/w/index.php?title=Po_(river)&oldid=1232644444"