The Fly River is the third longest
river
A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of ...
in the island of
New Guinea
New Guinea (; Hiri Motu: ''Niu Gini''; id, Papua, or , historically ) is the world's second-largest island with an area of . Located in Oceania in the southwestern Pacific Ocean, the island is separated from Australia by the wide Torres ...
, after the
Sepik River
The Sepik () is the longest river on the island of New Guinea, and the second largest in Oceania by discharge volume after the Fly River. The majority of the river flows through the Papua New Guinea (PNG) provinces of Sandaun (formerly West Se ...
and
Mamberamo River
The Mamberamo (''Indonesian: Sungai Mamberamo'') is the second longest river on the island of New Guinea, after Sepik River (1,146 km) and third largest in Oceania by discharge (5,500 m3/s) volume after Fly River (7,500 m3/s) and Sepik (7,00 ...
, with a total length of and the largest by volume of discharge in
Oceania
Oceania (, , ) is a geographical region that includes Australasia, Melanesia, Micronesia, and Polynesia. Spanning the Eastern and Western hemispheres, Oceania is estimated to have a land area of and a population of around 44.5 million ...
, the largest in the world without a single
dam in its catchment, and overall the 20th-largest primary river in the world by discharge volume. It is located in the southwest of
Papua New Guinea
Papua New Guinea (abbreviated PNG; , ; tpi, Papua Niugini; ho, Papua Niu Gini), officially the Independent State of Papua New Guinea ( tpi, Independen Stet bilong Papua Niugini; ho, Independen Stet bilong Papua Niu Gini), is a country i ...
and
Papua Province
Papua is a province of Indonesia, comprising the northern coast of Western New Guinea together with island groups in Cenderawasih Bay to the west. It roughly follows the borders of Papuan customary region of Tabi Saireri. It is bordered by ...
of
Indonesia
Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Gui ...
. It rises in the
Victor Emanuel Range
The Victor Emanuel Range is a limestone mountain range in the New Guinea Highlands of western Papua New Guinea. It was named after the King of Italy by the Italian naturalist Luigi D'Albertis while he was charting the course of the Fly River, ...
arm of the
Star Mountains, and crosses the south-western lowlands before flowing into the
Gulf of Papua
The Gulf of Papua is located in the southern coast region of New Guinea. It has a total surface area of .
Geography
Some of New Guinea's largest rivers, such as the Fly River, Turama River, Kikori River, Purari River, and Wawoi River flow ...
in a large
delta. The Fly-Strickland River system has a total length of making it the longest river system of an island in the world, including
Strickland River is the longest and largest tributary of Fly River, making it the farthest distance source of the Fly River.
Description
The Fly flows mostly through the
Western Province of
Papua New Guinea
Papua New Guinea (abbreviated PNG; , ; tpi, Papua Niugini; ho, Papua Niu Gini), officially the Independent State of Papua New Guinea ( tpi, Independen Stet bilong Papua Niugini; ho, Independen Stet bilong Papua Niu Gini), is a country i ...
and for a small stretch, it forms the
international boundary
Borders are usually defined as geographical boundaries, imposed either by features such as oceans and terrain, or by political entities such as governments, sovereign states, federated states, and other subnational entities. Political borders ca ...
with
western New Guinea
Western New Guinea, also known as Papua, Indonesian New Guinea, or Indonesian Papua, is the western half of the Melanesian island of New Guinea which is administered by Indonesia. Since the island is alternatively named as Papua, the region ...
. This section protrudes slightly to the west of the
141°E longitude line. To compensate for this slight gain in territory for Papua New Guinea, the border south of the Fly River is slightly east of the 141°E longitude line. As part of this deal, Indonesia has the right to use the Fly River to its mouth for navigation.
The principal tributaries of the Fly are the
Strickland and the
Ok Tedi.
Close to its mouth, the flow of the Fly River encounters a
tidal bore
Tidal is the adjectival form of tide.
Tidal may also refer to:
* ''Tidal'' (album), a 1996 album by Fiona Apple
* Tidal (king), a king involved in the Battle of the Vale of Siddim
* TidalCycles, a live coding environment for music
* Tidal (se ...
, where an incoming high tide pushes water upstream until the tide changes. The range of this tidal bore is still undocumented.
Delta
The
delta of the Fly River is over 100 km wide at its entrance, but only 11 km wide at the apex upstream of
Kiwai Island. The delta contains 3 main distributary channels (the Southern, Northern, and Far Northern Entrances) that branch from a common point (the “apex”). The distributary channels are 5 to 15m in depth, separated by elongate, sand-mud islands that are stabilised by lush mangrove vegetation. The islands are eroded and rebuilt rapidly in the apex area, where they have lateral migration rates of up to 150 m/a, with slower rates for the more seaward islands. Upstream from the apex the river gradually narrows to a width of 1.6 km or less. The Fly Delta exhibits a distinctive funnel shape in plan view, attesting to the fundamental role of tidal currents in shaping the Delta's geomorphology. Mean spring tidal ranges are amplified within the delta, from around 3.5m at the seaward entrance of the distributary channels, reaching a peak of about 5m at the delta apex. Seismic profiles and radiometrically dated core samples indicate that the delta is prograding seawards at an average rate of about 6 m/a
The Fly Delta is considered as a global "type case" of a tide-dominated delta and the patterns of sedimentation seen in the Delta today have been studied by sedimentary geologists as a model for interpreting the ancient rock record
The river delta is studded with low and swampy islands covered with mangrove and nipa palm, with villages and cultivated areas on these islands. The land on both sides of the estuary is of the same character. The islands in the estuary are flat and covered with
thick, fertile alluvial soil. The largest islands are
Kiwai Island,
Purutu Island
Purutu Island is the second largest island in the Fly River delta, Papua New Guinea, after Kiwai Island
Kiwai Island is the largest island in the Fly River delta, Papua New Guinea. It is one of the Torres Strait Islands. It is 59 km long al ...
,
Wabuda Island
Wabuda Island is the third largest island in the Fly River delta, Papua New Guinea, after Kiwai Island
Kiwai Island is the largest island in the Fly River delta, Papua New Guinea. It is one of the Torres Strait Islands. It is 59 km long alo ...
,
Aibinio Island,
Mibu Island
270px, Mibu Toy Museum
is a town located in Tochigi Prefecture, Japan. , the town had an estimated population of 39,158 in 16,149 households, and a population density of 640 persons per km². The total area of the town is .
Geography
Mibu is lo ...
, and
Domori Island Domori is an Italian company which produces chocolate products. Domori has its headquarters in None, just outside Turin, Italy and since 2006 has been part of Illy Group.
History
Domori was founded in 1997 by Gianluca Franzoni. In 1993, after st ...
. Kiwai, Wabuda and Domori are inhabited.
A list of the river delta islands is:
The inhabitants of the Fly River delta engage in agriculture and hunting. Coconut palm, breadfruit, plantain, sago palm, and sugar cane are grown.
Fly River turtle
The
Fly River turtle, also known as the Pig-nosed turtle due to its odd nose, is notably different from other turtles due to its piglike nose. The only freshwater turtle to have flippers, the turtle is known to rarely leave water, except in dire circumstances. They are also known to be omnivores who rarely consume meat.
History
The Fly was first discovered by Europeans in 1845 when
Francis Blackwood, commanding the
corvette
A corvette is a small warship. It is traditionally the smallest class of vessel considered to be a proper (or " rated") warship. The warship class above the corvette is that of the frigate, while the class below was historically that of the slo ...
HMS ''Fly'', surveyed the western coast of the Gulf of Papua. The river was named after his ship and he proclaimed that it would be possible for a small steam-powered boat to travel up the mighty river.
In 1876, Italian explorer,
Luigi D'Albertis
Luigi Maria D'Albertis (21 November 1841 – 2 September 1901) was an Italian naturalist and explorer who, in 1875, became the first Italian to chart the Fly River in what is now called Papua New Guinea. He undertook three voyages up this river ...
, was the first person to successfully attempt this when he travelled 900 km into the interior of New Guinea, in his steamer, ''Neva''. It was the furthest any European explorer had ever been into the island.
[
]
Environmental issues
Both the Strickland and the Ok Tedi Rivers have been the source of environmental controversy due to tailings waste from the Porgera Mine and the Ok Tedi Mine, respectively. Sediment sampling and coring in the distributary channels of the Fly Delta had not detected copper concentrations significantly higher than background as of 1994. In 2008, Ian Campbell, a former advisor to Ok Tedi Mining Limited, claimed that company data suggest significant portions of the Fly River floodplain are at a high risk from acid mine drainage
Acid mine drainage, acid and metalliferous drainage (AMD), or acid rock drainage (ARD) is the outflow of acidic water from metal mines or coal mines.
Acid rock drainage occurs naturally within some environments as part of the rock weathering ...
.
See also
*Ok Tedi environmental disaster
The Ok Tedi environmental disaster caused severe harm to the environment along of the Ok Tedi River and the Fly River in the Western Province of Papua New Guinea between around 1984 and 2013. The lives of 50,000 people have been disrupted. One o ...
References
{{Authority control
Rivers of Papua New Guinea
Gulf of Papua
International rivers of Asia
International rivers of Oceania
Indonesia–Papua New Guinea border
Western Province (Papua New Guinea)
Rivers of Papua (province)
Rivers of Indonesia