Road Construction and Kerinci Seblat National Park Part 1.5: Malapetaka!

Graphic from Padang Ekspres

In the last post I mentioned that I would focus on the ecological and environmental impacts of roads.  I'm going to postpone that discussion so that I can talk about a mini-crisis that has gripped Sungai Penuh over the past couple of days.  Last week torrential rains caused widespread flooding and other calamities in the Kerinci valley and surrounding regions, including Solok Selatan district and Pesisir Selatan district, both of which share borders with Kerinci Seblat National Park.  While the flooding and landslides caused by the rains are tragic, the provide an illustration of several points I made in the last post.

Map from welt-atlas.de

As I mentioned in the last post, Sungai Penuh, in the middle of the Kerinci Valley, is served by three roads to the wider world.  Two roads take different routes to Padang, a city of just over one million people 6-7 hours to the north.  The other road follows a tributary of the Batang Hari river south out of the valley towards Bangko and on further to Sarolangun and Jambi, 11 hours away to the east of Sungai Penuh.  The Bukit Barisan mountains, which form a spine longitudinally down the western side of Sumatra, are the major obstacle.  These mountains make it difficult to get in or out of the valley and this is what has spurred the call for new roads to link up "isolated" areas like Lempur village.  So as you can imagine, with only three roads in or out, if one of them is put out of commission for some reason or another, commercial havoc is wrought on the denizens of the valley.

This is exactly what happened a couple of days ago.  The floods, exacerbated by the longer-than-normal dry season (1), triggered several longsors or mudflows, one of which completely blocked one of the routes to Padang (known locally as the Tapan road).  Normally this road is used mainly by truck traffic delivering goods (including gasoline) from Padang in the north and the port at Painan on the west coast.  The longsor covered the road, and so for the past few days gasoline has been in short supply.  I noticed it first when I went down to Lempur on Saturday: a line of cars and trucks extending for probably 300 meters in either direction from the Pertamina (2) station in south Sungai Penuh.  I'd never seen anything like it; the only thing that comes close is pictures of fuel lines in the US in the early 1970s caused by the OPEC oil embargo.

Traffic snarl caused by line at the Pertamina

Pertamina with Pit-bound profiteer in foreground

This morning the story was the same.  I didn't want to face the crowd, but I was down to my reserve tank, and to me it's always good to have a full-tank when you're in a foreign country, so after the two meetings I had scheduled were cancelled because the meetee didn't show I made my way up the hill to another Pertamina.  Motorcycles and stepthroughs swarmed around the lone pump like worker bees on the queen, while scores of cars and trucks queued up.  Then from across the street I spied a roadside gasoline stall.  These are common in Indonesia as Pertaminas are sometimes few and far between.  Trucking and bartering in a way that would make Adam Smith proud, small-time entrepreneurs fill jerry cans with gas to sell to passing motorists.  I usually avoid them because I worry about impurities in the gas, but today the convenience was too much to resist.  Normally gas is about .59 cents a litre, or $2.25 or so a gallon in Indonesia.  You generally pay a bit of a premium on the roadside, but today the price was 10,000 rupiah per litre; about $1.10, or $4.16 a gallon.  This is a four-fold jump in the price of gas.  Friends told me that in some places the price was as high as 20,000 rupiah per liter.  I didn't want to wait around, so I forked over 50,000 rupiah for 5 liters, made some snide remarks about the special hell waiting for profiteers and gougers, and kabured.  I did take the opportunity to make some pictures and talk to some of the folks waiting.  One gentleman told me he had been there an hour already, and it looked like he had at least another hour to go.  He also told me that they are rationing gas at this point, so you can't get a full tank.

The reason I'm writing this post is because I think the road advocates will use the fuel shortage as support for the position that a new road is needed.  What better proof could you ask for?  It's especially timely since the investigative team I mentioned in the previous post is currently examining the proposed roads.  All it takes is one landslide to cripple the economy of the valley; think of all the productive hours lost while civil servants wait in line at the pumps (3).  Now imagine what would happen if the local volcano erupted, covering one of the existing roads in lava or lahar while thousands attempted to flee the valley.

But there's another side to the debate.  Though it's hard to prove at this point, the longsor that closed the road was most likely due to a) deforestation, b) poor engineering, or c) a combination of the two.  I've written previously on how cutting down trees undermines the stability of slopes.  Trees have extensive root systems which help to anchor the ground in place.  Cut down the trees and you lose the anchors.  Trees are especially important in tropical places (like Indonesia) where there is a lot of rain.  For some insight into the second possibility, have a look at the picture to the left.  I took this photo of a road cut on the way to Lempur last Saturday.  Look how steep the slope is.  There's no buttressing or anything else to add stability.  As you can see, erosion has already started, though the cut is only a year or so old.  These types of things are common around here, and the result is pretty predictable.  Shear stress eventually exceeds shear strength, and it all comes tumbling down.

So is the answer more roads, or is it more money and better engineering?  I don't know the answer to that question, but for the time being it looks like the former is going to win out. 

NOTES

(1)  When the ground is dry less water is able to infiltrate (seep down into the ground).  Once the ground is a little bit moist it is much more permeable.  So very dry ground often makes flooding worse.  

(2)  Pertamina is the state-owned petroleum company; most if not all gas stations in Indonesia are Pertamina stations. 

(3) 

The Temples of Dieng Plateau

This weekend I was fortunate enough to be invited out of the city on a day trip to the Dieng Plateau. I've been working pretty hard lately, and the Dieng plateau is one of the few "on-the-map" places in this part of the country that I hadn't yet visited, so I gladly jumped at the opportunity. The Dieng plateau is about 2000 meters above sea-level in Central Java in the region of Wonosobo. Dieng (from Di Hyang, "Place of the Gods") is the home to several Hindu temples dating from around 12-1300 years ago. Compared to the masterpieces at Borobudur and Prambanan these temples are relatively plain, but they were built a couple of hundred years prior. These temples are neat because they represent a mixture of Javanese culture with the Hindu religion and don't really resemble other Hindu temples in India. They were built here in memory of ancestors in the hopes that the spirits would continue to protect the living. They are dedicated to the god Shiva, who was the favored god of the Javanese Hindus. There isn't much of a written record concerning the temples, and for a long time they were all but lost to the outside world. However, they were "rediscovered" in 1814 (1) by a British soldier vacationing in the area. At that time they were submerged in a lake! Around the middle of the 19th century the Dutch colonial authorities started draining the lakes and cataloging the sites. The picture you see is from the Arjuna complex



The Dieng Plateau is also a volcanic landscape (technically a "complex volcano", an "an extensive assemblage of spatially, temporally, and genetically related major and minor volcanic centers with their associated lava flows and pyroclastic rocks [Francis, 1994]), and the tell-tale features that provide a clue to the tectonic violence just beneath the surface of the Earth are a significant attraction here as well. There are a couple of stratovolcanoes ( including the Sumbing and Sondoro volcanoes)here and a number of craters. Other features include fumaroles, which are volcanic openings in the earth's crust where gas and steam escape, and solfataras, which are fumaroles that emit sulfurous gases (2). All of these features suggest that the Dieng area has been affected by numerous phreatic eruptions. Phreatic eruptions happen when magma rising from below comes into contact with water beneath the surface. This causes the water to quickly turn into steam, which increases the pressure below the ground. When enough pressure builds up there is a violent, explosive eruption that sends steam, ash, rock, and water everywhere. As you can imagine, the Dieng plateau can be a very dangerous place, not just for the phreatic eruptions but also due to the fumaroles. For example, in 1979 149 people were killed when they tried to flee the area. For several days there had been signs of an impending eruptions, so some villagers decided it was a good time to head for the hills (3). Several days later the villagers were found dead on the trail, lined up as though they were walking. Authorities presumed they all suffocated when a cloud of poisonous gas descended upon them. But despite the dangers, the Dieng plateau, because of its cooler temperatures and rich soils, is an important agricultural region. The government has also initiated a geothermal project to generate electricity. We stopped at a hot spring where water and gas bubble up from below. If you've ever wondered what it smells like when the earth farts, you should visit this place. The smell comes from sulfur, one of the principle substances ejected from volcanoes and springs. I've included a video clip of the bubbling pool for your viewing pleasure. Unfortunately the blogging software doesn't come equipped with Smell-O-Vision.

One of the best things about the trip, though, was getting there. During the 3 hours it took to go from Jogja to the plateau we passed through some stunning scenery. Climbing into the mountains you'll pass miles and miles of vegetable farms. The milder climate allows farmers to grow a wide variety of produce, including potatoes. But the striking thing about the agricultural landscape is the density of it; virtually every nook and cranny is planted with some sort of vegetation. Entire hills have been completely given over to terracing. And while this enables increased agricultural production, the environmental consequences are very apparent: slope failures that have resulted in landslides. I've included a series of photos to the right to give you an idea of how this happens. In the first picture (sorry about the blur; I took it from the car) you can see a farmer working on freshly terraced area. Terraces are created by removing all the vegetation and cutting into the mountain to create a level surface for planting. This has two very negative effects: 1) the trees and other vegetation serve as anchors for the soil; their roots help keep the soil in place, and 2) the walls of the terrace increase the slope of that part of the hillside to nearly 90 degrees, which increases "shear stress" and weakens the structure of the slope. In the second picture you can see an entire hill covered with terraces. Nearly all of the original vegetation has been removed and only a few trees remain. In the third picture you can see the unfortunate results of this farming strategy: a landslide. The one in this picture is a relatively small one, but in some cases a significant portion of the hill comes tumbling down. Although the farmers construct rock walls to reinforce some of the terraces, it's usually just a matter of time before a landslide happens in this very rainy environment.

(1) For a short time between 1811 and 1818 the British controlled Java. This was a part of the Napoleonic Wars in Europe. France's Napoleon conquered the Netherlands, and thus took over all the Dutch colonies. France's enemy, England, then invaded Java and after 45 days took control. The English ceded control back to the Dutch at the end of the war.

(2) The name solfatara comes from a crater of the same name near Naples, Italy. Although the volcano is dormant, it still emits sulphurous gas.

(3) Or, in this case, out of the hills...

References:

Francis, P. 1994. Volcanoes: A Planetary Perspective. Oxford University Press, New York, 443pp. Via Oregon State's Volcano World site.

Van Bergen, Manfred, Alain Bernard, Sri Sumarti, Terry Sriwana, and Kastiman Sitorus. 2000. Crater Lakes of Java: Dieng, Kelud, and Ijen. Excursion Guidebook for IAVCEI General Assembly, Bali 2000. Find Here....