Monday, June 20, 2011

Lentang Forest Recreational Park (Air Terjun / Hutan Lipur Lentang)

Benus River in the Lentang Forest Recreational Park
Lentang waterfall is actually not a waterfall, but a stretch of the Benus River as it drops through a large section of granitic boulders.  The Benus forms in the mountains above Kampung Janda Baik and picks up the Sum Sum River just downstream of the Kampung.  It flows through a Recreational Forest Park (Hutan Lipur) before emerging from the jungle and going under the Karak Highway.  The Karak is the major east-west roadway which carries people from the population centre of Kuala Lumpur to the east coast and north through Bentong and the township of Karak.  It is a great place to stop for a picnic, swim in the slower, lower section or to enjoy a cooling soak in the upper boulder stretch.

If you are driving from Kuala Lumpur eastward, look for the exit sign after passing through the tunnel and going past Genting Sempah.  It is several kilometers down the hill with an exit to the left and back under the highway.  If you are going UPhill towards KL, then the exit is a simple left exit to the front gate.
Boulder Rapids (not a Waterfall)
The lower part of the Benus River is wide and shallow, with a sandy bottom, and is a picnic/swimming (wading) section for families and children.  For the more adventurous (not that much more), there is a section further upstream of a boulder patch in which the water drops down through with small pools and great sounds.  Boulder rapids are not true waterfalls, but if one has tinnitus, they are great at providing white noise to sooth the soul.  (Put the following video on a loop and see if I'm correct!)

Benus River Suspension Bridge
Massive Leaves
Like a lot of Malaysian recreational areas, they have tacked signs up to several trees indicating the genus and species, and sometimes with more information like uses of the tree.  I like that feature since the Malaysian rain forest has an incredible diversity of trees, bushes, butterflies, flowers, insects, birds, and trash.  (Need I say it, this recreational park has its own set of food outlets.)
Another Shorea species
Walking up the road a short ways beyond the food stalls, I came to a side stream which has a wading pool built at the bottom of a diversion wall.  Further upstream, I found a very sharp, steep, V-shaped canyon that has all of the features of a landslide-scoured channel.
Side Canyon With Channel Scour to Bedrock
The photo above shows water flowing directly on top of bare bedrock (i.e., no streambed gravels) with an isolated patch of forest in the middle.  There is a true knickpoint (waterfall) in the background just visible as a patch of white to the left of the tree on the far right side.  (Some day when I have more time available -i.e., no one waiting for me to stop my canyon climbing- I want to take a hike further upstream.)  There is a story here.

Here is a closer shot of the flow over bare bedrock.
Flow Over Bare Bedrock
The regolith in this canyon is quite exposed along the edge, another indication that a pile of rocks and soil were flushed out of this section during some large rainstorm-induced flow in the past.

Exposed Regolith
The rocks in this area are full of feldspar crystals, which indicates rocks in the granite family, but these were somewhat low in quartz, thus, something like a diorite or gabbro.  (I need a real geologist to take a look and tell me what the following photo shows.)
Feldspar Crystals in Bedrock Boulder
This side canyon is just uphill from the boulder stretch on the Benus River, so one can surmise that many of the boulders in the Benus (well-rounded) came down from this canyon and were eroded by the flow of the river.
But, hey, this blog post is getting a bit rocky now so I'll just say that the Lentang Park is a great place to stop off on a hot day, and there are a lot those in Malaysia!


  1. mengingatkan kenangan masa pegi air terjun lentang.

  2. Sama sama. Malaysia ada banyak tempat macam ni yang sangat cantik dan sunyi.