Annong River Diversion Weir is a water-control structure spanning the Annong River in Sanxing Township, Yilan; the Taiwan Provincial Government decided to build it in 1979, and it was completed in 1988 to resolve long-running irrigation and flood-drainage disputes between Sanxing and Dongshan townships. The Annong River was originally called Dianhuo ('Electric Fire') Creek, named for the tailwater discharged after the Tiansongpi Hydroelectric Plant was completed in 1922 under Japanese rule; after the weir's completion, the river was renamed 'Annong,' meaning 'farming now at peace.' A trail runs along the top of the weir, offering a view over the still water impounded upstream and the farmland downstream, in an area known for Sanxing scallion and garlic production.
The Annong River was originally called Dianhuo Creek, named for tailwater discharged after the Tiansongpi Hydroelectric Plant was completed in 1922. Due to long-standing water-rights disputes between Sanxing and Dongshan townships, the Taiwan Provincial Government decided to build the diversion weir in 1979; it was completed in 1988, when the river was renamed Annong. A roughly 2-hectare sandbar downstream of the weir was developed into a spring-water park in 1992, now part of the diversion weir scenic area.
Highlights of Annong River Diversion Weir
The Annong River is a tributary of the Lanyang River system, flowing through Sanxing Township before joining the Lanyang River. The diversion weir's primary function is water-flow regulation to reduce downstream flooding. A waterside trail has been built along the top of the weir — it is not long, the slope is gentle, and it is walkable by visitors of all ages. The weir-top view is broad: the contrast between the impounded water surface upstream and the gravel riverbed downstream, combined with the surrounding farmland extending to the distant mountains, is the main visual content here.
Sanxing Township's agricultural practices retain a relatively traditional, labor-intensive approach; the scallion growing cycle means the farmland scenery changes with the seasons. A cycling path runs along the Annong River, with some sections fully paved — the main leisure cycling route within Sanxing Township. There are no dining facilities near the weir; it is recommended to eat in Sanxing town center before heading out.
How to make the most of your visit
Practical information
Getting there and travel time
- Drive from Sanxing town center in the direction of the Annong River; there is no direct public transport, so driving or cycling is recommended.
- Tiansonpi is about 10 to 15 minutes by car from Sanxing town center; road conditions are good, though surrounding roads are mostly farm tracks — watch out for agricultural vehicles.
Nearby connections
- Within Sanxing Township, Xingjian Organic Village and other agricultural experience sites can be combined to learn about Yilan's organic farming practices.
- Heading north connects to Datong Township, with Taipingshan or Mingchi as extensions for a mountain itinerary.
Sources: Yilan County Sanxing Township Office; Wikipedia entry on 'Annong River.' Photos to be replaced with Dio's own shots.
Frequently Asked Questions
When was Annong River Diversion Weir built?
The Taiwan Provincial Government decided to build it in 1979, and construction was completed in 1988.
What was the Annong River originally called?
It was originally called Dianhuo Creek, named for tailwater from the Tiansongpi Hydroelectric Plant completed in 1922; it was renamed Annong after the weir was finished.
Why was the diversion weir built?
It was built to resolve a long-running dispute between Sanxing and Dongshan townships over irrigation intake and flood drainage by splitting the river's flow.
What scenery surrounds the weir?
The area is a major production region for Sanxing scallions and garlic, and the trail along the weir top overlooks the still water and downstream farmland.
Sources
- 第一河川分署-蘭陽新祕境-前瞻安農溪的前世今生 — 分洪堰興建年份、電火溪改名沿革
- 安農溪分洪堰 - 國家文化記憶庫2.0 — 湧泉公園闢建年份、面積