Tidal Bore at Batang Lupar

A tidal bore, locally known as “Benak”, usually occurs during the third day and eighteenth day of the Chinese Lunar calendar month and when the high tide is rushing up the Batang Lupar.

The tidal bore is created when the force of the tide water rushing up the river causes the river to reverse its flow. The height of the tidal bore depends on the time of the year, weather and phase of the moon. The tidal action is significant for the speed in which a large volume of water fills the river channel.

The tidal bore in the Batang Lupar reaches its height at the river in front of the Sri Aman Town, which is about 28 kilometres from its mouth. The tidal bore travels further up river for another 30 kilometres to reach Engkilili, a total of 68 kilometres from the sea.

Me at Batang lupar during tea time.

Tidal Bore Phenomenon

Tidal bore is a solitary wave formed when a rising tidal front tries to enter a shallow and narrowing river with high tidal range from abroad estuary. In the process, the tidal front is retarded by the river flow and the bed friction start to build up. When it reaches the critical point, it breaks and moves forward upstream as a rushing wave called tidal bore. As it travels upstream, it will decrease in height and velocity and eventually dies out due to energy dissipation. In Malaysia, tidal bore phenomenon can only be seen at Batang Lupar, Batang Sadong, Batang Samarahan and Batang Saribas in the state of Sarawak.

Sri Aman is situated about 194 kilometres by road from Kuching City. The unique phenomenon of tidal bore occurrs in Batang Lupar. Batang Lupar flows from the Klinkang Range to South China Sea with river length of 275 kilometres. Geographicaly, Batang Lupar has a big opening at the rivermouth and becomes narrow when it reaches upstream. It is believed that tidal bore starts at Pulau Seduku located about 44.6 kilometres from river mouth and 34.5 kilometres from Sri Aman town. Tidal bore or locally known as benak occurs everyday with different wave lengths and heights. However, during spring tide, normally on the third and eighteen day of the Chinese Lunar Calendar, tidal bores with high magnitude can be observed clearly.

There is no detailled study on the tidal bore Batang Lupar. However, based on naked eyes observation, the velocity of the tidal bore is about 7 km/hr to 18km/hr with heights at times reaching to more than 3 metres. The formation of tidal bored depends on several factor as listed below:

1. Tidal range: neap tide & spring tide
2. Shape and slope of the river
3. Overall depth of the river channel
4. Weather condition and flow of river at upstream

Sarawak State Government recognises Pesta Benak (Tidal Bore Carnival) in Sri Aman as one of yearly activity in the Sarawak tourism calendar. The objective of Pesta Benak Sri Aman is to introduce Sri Aman town through tourism and encourage tourist from in and outside the country to visit Sri Aman. Apart from it, Pesta Benak is also to encourage harmonial spirit among local community.
In conjuction with this festival, there were many events organized such as development exhibition, food fair, karaoke competition, culture and art performances, development exhibitions and others.  In conclusion, tidal wave festival has made the area a popular spot in Sarawak for visitors, you can join in the fun and hitch a ride with the longboats or just watch the boatman braving the waves. You can even immerse yourself with the local culture at the food fair, good music and dance performances that are part and parcel of the festival.

The Legend of the Benak

A local legend states that once upon a time, Benak, his wife and their son were strolling along the Batang Lupar, in the Sri Aman division of Sarawak, when they accidentally hit and capsized a native, spilling him into the Batang Lupar.

Angered by this, the native, a local Iban man, vowed to avenge his misfortue and kill Benak and his family.

The next morning, the Iban man hid himself on the Batang Lupar to await the arrival of Benak and his family. Unaware that he was waiting for them, Benak and his family were unexpectedly attacked by the local, and Benak was slain.

But, his wife and child managed to escape, and every day since they stroll the Batang Lupar with great ferocity, and no compassion for the local boatmen that frequent the waters.

The Yellow Streak

Published in 1949, the English novelist Somerset Maugham’s Borneo Stories series contains a short story entitled The Yellow Streak. In it Maugham relates his near-death experience when he encountered the Benak on the Batang Lupar.

The writer was paying a visit to the Third White Rajah, Rajah Brooke, in 1924. At the Rajah’s invitation, Maugham was travelling by boat along the Batang Lupar, rowed by prisoners of the Rajah, to the town of Simanggang (now known as Sri Aman).

During his voyage, Maugham unexpectedly encountered the mighty tidal bore, was thrown from the boat, and narrowly avoided drowning. The account in The Yellow Streak illustrates Maugham’s oppinion of the benak, and that it clearly upset him nearly bringing his eminent writing career to an abrubt and untimely end.

Sources:
Gushing Roar of Sarawak’s Tidal Bore, By Martin Yee, New Strait Times Press, 21st February 2000
Brunei: Tidal Bore Fest, Borneo Bulletin, 6th June 2001, Copyright 2001 FT Asia Intelligence Wire

We went Padang, Indonesia in 6th - 7th March 2009 on a tour of 22 people consist of 4 families. It was a very interesting trip. I know myself and the other uncle I saw is the only guy in the group, minus the driver and the tour guide of course, but I rather had a great deal of time sight-seeing-while-waiting compare to the ladies shopping. Hahaha. :)) Got one time where I was the one to board the bus pariwisata (bas persiaran in Malay), and they asked me how much the kain i bought. Once the heard it’s cheap, a group of them went back off the bus into the same shop they went again. :))

Padang is actually the main city of the state Sumatera Barat. Like Shah Alam for Selangor. We didn’t actually spent much of the time there instead the places of interest are located in Bukit Tinggi, 90 km away from Padang. The picture above is us in Bukit Tinggi. Behind is called Jam Gadang where it was built back during the time of Dutch occupancy of Indonesia. Various places of interest located there including Lobang Jepang, Ngarai Sianok, Pasar Atas, Pasar Bawah, Lake Maninjau and others. Mainly, a lot of textile for baju kurung, kebaya and kebarung are suitable to buy for shopaholics. It’s a minang