The Dahan River (, also spelled Tahan) is a river in northern
Taiwan
Taiwan, officially the Republic of China (ROC), is a country in East Asia, at the junction of the East and South China Seas in the northwestern Pacific Ocean, with the People's Republic of China (PRC) to the northwest, Japan to the nort ...
. It originates in
Hsinchu County
Hsinchu County (Wade–Giles: ''Hsin¹-chu²'') is a county in north-western Taiwan. The population of the county is mainly Hakka; with a Taiwanese aboriginal minority in the southeastern part of the county. Zhubei is the county capital, where ...
and then flows through
Taoyuan City
Taoyuan () is a special municipality (Taiwan), special municipality of the Taiwan, Republic of China (Taiwan) located in northwestern Taiwan, neighboring New Taipei City to the north-east, Yilan County, Taiwan, Yilan County to the south-e ...
and
New Taipei City
New Taipei City is a special municipality located in northern Taiwan. The city is home to an estimated population of 3,974,683 as of 2022, making it the most populous city of Taiwan, and also the second largest special municipality by area, be ...
for 135 km, before it joins
Xindian River
The Xindian River (or Xindian Creek) () is a river in northern Taiwan. It flows through New Taipei and the capital Taipei for .
Overview
The Xindian River is one of the three major tributaries into the Tamsui River. Its main tributary is the Be ...
in
Taipei
Taipei (), officially Taipei City, is the capital and a special municipality of the Republic of China (Taiwan). Located in Northern Taiwan, Taipei City is an enclave of the municipality of New Taipei City that sits about southwest of the n ...
to form the
Tamshui River. The upper reaches of the Dahan are also known as Takekan Creek () or Taigang Creek (泰崗溪). An alternative historical name for the Dahan is the Shihmen River (石門溪).
Geography and geology
The Dahan River begins on
Pintian Mountain
Mount Pintian () is a mountain in Taiwan.
Geology
The mountain stands with an elevation of and is part of the Shei-Pa National Park.
See also
*100 Peaks of Taiwan
*List of mountains in Taiwan
*Shei-Pa National Park
Shei-Pa National Park () ...
in
Hsinchu County
Hsinchu County (Wade–Giles: ''Hsin¹-chu²'') is a county in north-western Taiwan. The population of the county is mainly Hakka; with a Taiwanese aboriginal minority in the southeastern part of the county. Zhubei is the county capital, where ...
, near the border of
Shei-Pa National Park
Shei-Pa National Park () is a national park located in the central part of Taiwan around the peaks of Hsuehshan and Dabajian Mountain, with an area of , covering the area of Hsinchu County, Miaoli County and Taichung City. High mountain ecology, ...
, at the confluence of Takekan Creek (大嵙崁溪)and the Baishi Creek (白石溪)near
Jianshi town. The Takekan, the larger of the two is sometimes considered part of the
main stem
In hydrology, a mainstem (or trunk) is "the primary downstream segment of a river, as contrasted to its tributaries". Water enters the mainstem from the river's drainage basin, the land area through which the mainstem and its tributaries flow.. A ...
. It flows north through a narrow gorge and receives the major tributaries of Sanguang Creek (三光溪), Lala Creek (拉拉溪), and Xibuqiao Creek (西布喬溪) from the east. At the Dongyanshan (East Eye Mountain) Recreation Area in
Fuxing, it turns west and flows into
Shihmen Reservoir
Shihmen Dam (; also spelled Shimen or Shihman) is a major rock fill dam across the Dahan River in northern Taoyuan City. It forms the Shihmen Reservoir (), Taiwan's third largest reservoir or artificial lake. It provides irrigation in Taoyuan, fl ...
, which is formed by the
Shihmen Dam
Shihmen Dam (; also spelled Shimen or Shihman) is a major rock fill dam across the Dahan River in northern Taoyuan City. It forms the Shihmen Reservoir (), Taiwan's third largest reservoir or artificial lake. It provides irrigation in Taoyuan, fl ...
. Below the dam it flows northeast across
Daxi District
Daxi District (), formerly known as Daxi Township (), is a district in eastern Taoyuan City, Taiwan. In March 2012, it was named one of the ''Top 10 Small Tourist Towns'' by the Tourism Bureau of Taiwan.
History
The Daxi area was occupied ...
, then into the
Sanxia District
Sanxia District () is a District (Taiwan), district in the southwestern part of New Taipei, Taiwan. It is the second largest district in New Taipei City by area after Wulai District.
Name
The old name of Sanxia, ''Sa-kak-eng'' () refers to t ...
of
New Taipei City
New Taipei City is a special municipality located in northern Taiwan. The city is home to an estimated population of 3,974,683 as of 2022, making it the most populous city of Taiwan, and also the second largest special municipality by area, be ...
, where it receives the
Sanxia River
The Sanxia River () is a tributary of the Dahan River in New Taipei City, northern Taiwan.依三峽鎮志第一章《地理》總計三峽溪幹流長約二八·五公里,較日治時期二三公里增長四公里餘,蓋河道變遷, ...
(三峽溪). It continues to flow northeast across New Taipei City until its confluence with the
Xindian River
The Xindian River (or Xindian Creek) () is a river in northern Taiwan. It flows through New Taipei and the capital Taipei for .
Overview
The Xindian River is one of the three major tributaries into the Tamsui River. Its main tributary is the Be ...
, which forms the
Tamsui River
The Tamsui River (alternatively Danshui River, ) is third longest river in Taiwan after Zhuoshui River and Gaoping River, with a total length of , flowing through Hsinchu County, Taoyuan, Taipei and New Taipei City. It is located in northern pa ...
.
The Dahan River once flowed north through the area of
Taoyuan City
Taoyuan () is a special municipality (Taiwan), special municipality of the Taiwan, Republic of China (Taiwan) located in northwestern Taiwan, neighboring New Taipei City to the north-east, Yilan County, Taiwan, Yilan County to the south-e ...
to empty into the Taiwan Strait about west of the mouth of the Tamsui River. The
Taoyuan Plateau
The Taoyuan Plateau () is a plateau located in northern Taiwan. It borders the Linkou Plateau in the northeast, the Hsuehshan Range in the southeast, the Hsinchu Hills in the south, and the Taiwan Strait in the west. In order to irrigate this ar ...
is the ancient
alluvial fan
An alluvial fan is an accumulation of sediments that fans outwards from a concentrated source of sediments, such as a narrow canyon emerging from an escarpment. They are characteristic of mountainous terrain in arid to semiarid climates, but a ...
of the Dahan River, created by sediments eroded from the mountains. About 30,000 years ago, tectonic movement caused the
Taipei Basin
The Taipei Basin () is a geographic region in northern Taiwan. It is the largest basin in Taiwan. The basin is bounded by the Yangmingshan to the north, the Linkou Plateau to the west, and the Ridge of Xueshan Range to the southeast. The shape ...
to drop in elevation, and the Tamsui River system
captured the Dahan River and caused it to flow northeast. As a result the Dahan River cut a canyon through the alluvial sediments for more than to reach the new lower elevation. The former channels of the Dahan River remain as "beheaded" streams that flow only seasonally across the plateau.
Dams
Due to the lack of a natural water source for the Taoyuan plateau, thousands of artificial ponds were constructed to capture summer rainfall for irrigation, making the area one of Taiwan's most productive agricultural regions. In 1928 the Taoyuan Canal was dug to divert water from the Dahan River near the present location of Shihmen Dam. The canal enabled a more constant water supply for Taoyuan and effectively returned water to old channels of the river that had been cut off thousands of years ago. Due to urbanization, the Dahan river is increasing in importance as a domestic water source, while the use for irrigation has decreased.
The Shihmen Dam, one of Taiwan's first multi-purpose water projects, was completed in 1964. It provides flood control, irrigation, domestic water supply and hydroelectricity for much of Taoyuan and New Taipei City. The dam has had problems with
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 with water. Silt usually has a floury feel when ...
build-up since its construction, due to the high rate of erosion caused by
typhoon
A typhoon is a mature tropical cyclone that develops between 180° and 100°E in the Northern Hemisphere. This region is referred to as the Northwestern Pacific Basin, and is the most active tropical cyclone basin on Earth, accounting for a ...
storms and earthquakes in the upper Dahan River drainage. About 123 "sabo dams" (
check dam
A steel check dam
A check dam is a small, sometimes temporary, dam constructed across a swale, drainage ditch, or waterway to counteract erosion by reducing water flow velocity. Check dams themselves are not a type of new technology; rather, the ...
s) have been built along the Dahan River upstream in order to block silt and extend the useful life of the Shihmen reservoir. Chief among these is the
Junghua Dam
Ronghua Dam () is a dam crossing the Dahan River, a tributary to the Tamsui River, in Fuxing District, Taoyuan City, Taiwan. , upstream.
NTPC Travel – Dahan River Left and Right Bank
/ref> The second largest dam, the Baling dam, failed during Typhoon Wipha in 2007, destroying Baling village and washing of silt into the Dahan River.
The Taiwanese government has proposed the construction of a mega-dam on the Takekan Creek known as Gaotai Dam (高台壩) to trap silt and provide additional water storage. This plan has been criticized due to its potential environmental damage, and its limited useful life, because the new reservoir would also eventually fill with silt.
Bridges
* Daxi Bridge
The Daxi Bridge () is a suspension footbridge in Daxi District, Taoyuan City, Taiwan. It connects Rui'an Road Section 1 and Daxi Old Street. The bridge is also known as the Lover's Bridge. History
The bridge was originally built in 1934 as a ba ...
* Luofu Bridge
The Luofu Bridge () is a bridge in Fuxing District, Taoyuan City, Taiwan.
Architecture
The bridge was built over the Dahan River along Provincial Highway 7. The iron arch bridge is long.
See also
* List of bridges in Taiwan
As of October ...
See also
*List of rivers in Taiwan
This is a list of rivers ( or ) on Taiwan Island in the Republic of China which are over :
* Dongshan River - Yilan County -
*Lanyang River - Yilan County -
**Yilan River - Yilan County -
** Qingshui River - Yilan County -
** Luodong Ri ...
References
{{commons category, Dahan River
Rivers of Taiwan
Landforms of Hsinchu County
Landforms of Taoyuan City
Landforms of New Taipei
Landforms of Taipei