The world's biggest morning glory

"The grass is one of our sensors" said Andrijanto, one of the managers of Jatiluhur dam. It is the third in a series of large dams storing part of the water supply of Jakarta. Nearby a herd of goats walked on the sloped face of the dam, far enough away that we could not hear the bells around their necks. Apparently, when the dam face starts leaking, the grass turns green and this is a low cost way of monitoring it. Maybe the goats are a low cost way of maintaining the sensor too.

Goats on the job, left

Jatiluhur also has the largest “morning glory” spillway in the world. It is shaped like a squat vuvuzela so water can flow over the top of it and down into the center.  Three other dams claim to have the largest such spillway (Whiskeytown Lake, Ladybower Reservoir and Monticello Dam, each around 25 meters/80 feet diameter) but Jatiluhur is wider than all of them combined (90 meters/290 feet). 

Walkway to the morning glory

 When asked if he’s been to the bottom of the spillway Andrijanto answers “Of course, of course!” Apparently willingness to go in the spillway is one of the conditions of working there (but not necessarily part of the job interview). Naturally, there have been times that he went to the bottom and co-workers joked that the crane to bring him back up was broken. I do think the original crane attached to the dam was broken, however.

The view down into the spillway. Note metal ladders at top of photo for scale.

The overhead view of the spillway from space on google maps

Group photo of water managers (in blue uniforms, Andrijanto is 3rd from the left) and researchers from Pusair. 

A few times during the tour of the grounds, Andrijanto touched on a theme of “The most important thing in water management is discipline.” Discipline to do routine maintenance. Discipline to stick to the plan, even during crisis. Discipline to have a plan. “Obey the rules, have discipline”.

It is something of a contradiction because every couple minutes he was eager to demonstrate some innovative feature they had implemented. There is only one Jatiluhur dam and it probably does not have a user guide (or rather the manual is likely 10 binders large... turn to page 2,968 for “what to do if goat falls in spillway”). They need practical creative solutions to one-of-a-kind problems. It seemed like when they ran out of ideas they asked the sage engineer who has worked there longer than I have been alive (next year he gets his 50-year pin). 

As we walked down the tunnel inside the dam to the base of the spillway (photos not allowed), the air gets hot and dank like the bottom of a mine. The air conditioner was not working that day. The tunnel openned to a flourescent lit cavern with turbines and control panels. Everything was cement and metal so there is nowhere for the sound to go as the turbines whir away. Some of the large machines were being field dressed, every part laid out orderly on a blanket.

Into the tunnel

It sounds like Andrijanto has thought about the dam day and night for the 10 years he has worked there. He is paid to worry... worry effectively. There is no room for self-deception. My impression is that his biggest fear is that some day something will go wrong with the dam and a pitchfork and torch-yielding angry mob will come and carry him away.

Problems do happen. Just two weeks ago a small spillway at Buaran Dam failed on one of the delivery canals far downstream. A bank gave away, causing water to flow back into Buaran River, cutting off water supply to the Pejompongan water treatment plant in Central Jakarta. Nearly 1 million customers were affected for days. They say it was a combination of a “natural disaster” and a lack of maintenance.

Andrijanto’s impression of forecasts? Before the largest flood in recent history, the climate forecasters were saying it was going to be dry, so the operators tried not to draw the reservoir down too much. In essence, they were told to zig and the climate zagged. Maybe this was climate change they thought.

What is a water manager to do in that situation? “We cannot reject the decision of the forecasting agency, they have the authority to make the forecasts” It is not the water manager’s place to second guess the forecasters. The forecasters are experts, that is their job. “They have the equipment to make the forecasts, not us”. Of course, like the US and Australia, the forecasters get feedback and suggestions from the water managers, such has how there might have been recent errors.

At this point, Andrijanto turned the tables and asked “Do you think that we have to review our models for climate forecasting in the future?” In essence, what do I think of climate change? Remember, the recurring theme to this point was to make a plan and stick to the plan... but make a new plan if it is clear that something else is needed. Do they need a new plan?

First, I do not know enough of the technical details about Indonesia’s systems to make any conclusions. Also, changes in predictability 1-3 months ahead is a subtly different issue than if the climate itself is trending or becoming more variable. But I said that, at least overseas, it is clear that the climate is changing and it is going to change in the future. Of course the models are wrong and are not going to work as well in the future. How things will change though is uncertain, so I cannot suggest a better plan than what they already have. It is like “the road is due for a curve, we just do not know if they should start turning left or right... Be prepared for a turn however”. Spoken like a true academic I suppose!

Control building with Mr Heru

We asked the senior engineer if he had any reflections after 49 years? He said that building the dam 1 meter higher would make it capable of handling the Probable Maximum Flood (basically the largest conceivable flood, the total worst case scenario). In the meantime, I suppose everyone has to expect the unexpected and hope that the angry mobs and goats keep at bay.

Interview with a NWS river forecaster

This webpage from the US National Weather Service has an interesting interview with one of their river forecasters. It gives a profile of what Andrea Holz does as a forecaster, how she became a forecaster, what some of the challenges of the job are, etc. It's recommended reading, I hope to do profiles like that for other forecasters.

Andrea Holz, forecaster featured in this profile. 

Hydrologic oddities: Linow lake

Lake Linow in Tomohon, North Sulawesi, Indonesia slowly changes color from red to green to blue every now and then. This is because there are sulfuric vents that change the mix of gases in the water. The shallows bubble and let off white smoke.

Here's a satellite image of the lake from Google Earth (in the green phase)

And some others from the ground...

(source)

White waters in foreground (source)

(source)

Happy birthday!

This morning I rolled out of bed, drew back the curtain and was faced with a volcano and about 2,500 Muslims in white responding to the call to prayer. In some time-zones it's still my 37th birthday.

The  (inactive) volcano Klabat. The active one is to the right.

My view of the call to prayer. Usually this is a playground. A military statue in the foreground is covered up in green cloth.

Today is Eid, the end of Ramadan, the biggest holiday of the year in Indonesia. 

Yesterday was spent on a tour of Tangkoko Nature Reserve in North Sulawesi. When we left in the morning, the hotel was running on an electric generator, the internet was down and the water pressure was low because the hydropower plants were straining under a two week drought now near the end of the dry season.


The day started off taking snaps of the streamgage (the yellow box) on the Kuala Tondano (Tondano River) where it crosses the Jalan Martadinata bridge. This is the largest river above Madano, draining a major lake.

As we walked into Tangkoko, we heard that Lonely Planet was filming a nature documentary there. The jungle has a very high Leaf Area Index, green everywhere.

Tangkoko's real draw however is the wildlife. It takes a careful eye to spot...

...unless a pack of 30 Black Macaques comes storming up...

Jungle Kitty and Black Macaque in tree.

We briefly merged with another group and their guides. 

The Black Macaques are expressive...

expressive in many ways. Here's the rest of the above photo, with modesty bars included:

We first heard about the park from a French diving instructor with a thick accent. She was enthusiastic about a certain kind of bear that she struggled to describe. She said they're like "Koala Bears"... They keep babies in a pouch. They have big eyes. They have a long tail that wraps around the tree. They have a long body. They are named like the pasta. It felt like the longer she talked the less we understood. We eventually found out the "Long Bears'" real name is Sulawesi Bear Cuscus, pronounced like "cous cous". 

My photo of the long bear

A better photo (source)

Not too different from a Koala Bear that was spotted nearby (staged).

We waited an hour for a Hornbill to come feed at its nest. 

Look closely for the flapping wings in the center of the photo. 

Someone else's photo (source)

What draws film crews in from all over is a small monkey that lives in a Strangler Fig tree.

Hiding in the gaps and only coming out at twilight is the Tarsier, the world's smallest primate. Note the two small glowing dots for eyes:

It jumps out, grabs its food and jumps back faster than you can see, much less take a photo of. This photo gives an idea of the relative size of its head to its body.

The Tarsier is also an Internet sensation for being the cutest animal ever found. 

(source)

On the way out of the jungle there was a tarantula:

and Kitty was menaced by a "75 centimeter long" cockroach in the Ranger Station office, captured here:

The ranger convinced us that they best way to combat jungle mites was a impromptu swim in the ocean.

Arriving back late to Manado, the streets were filled with a massive party. There were people dancing on top of parked cars, riding around blaring music, setting off fireworks. On getting back to the room, we turned on the TV and ran across an Animal Planet documentary that featured the wildlife (literally, the same animals) we had spent the day with ("I know that beach! We were at that tree!").  It was humbling to realize that the Tarsier monkey is nearly extinct and we were able to see them up close in their own habitat.

Ayung River in Bali, Indonesia

From where I'm sitting (a lobby in a hotel in a small town in Sulawesi), I can count 14 geckos on the wall. Last night the check-in clerk tapped a wall map "your room is here" and two lizards skitted out from behind it.

Last week was rafting on the Ayung River near Ubud in Bali. This small, free-flowing river passed through canyons and there were many waterfalls. At the end of the ride was a small side dam in part of the channel. Much of the landscape looks like this:

The green receptors in my eyes were completely saturated. 

Many of the photos from this post were taken from other webpages (sources 1 , 2 ,3 ,4 ,5 ,6 ,7 ,8 ,9 ,10 ,11 ,12) because I was concerned about getting the phone wet... but straight after the first bend was an unexpected delight. I caused a stir on the raft with all my "ooh! ooh!"-ing ("what is it? waterfall? monkey? snake?"). There was an automated river gage. It looks like a tall metal tube with a small shack on the top.

Even more unexpected was that there was another gage a few more minutes downstream, almost identical to the first, except that the bottom of the tube looked torn away. I've googled up one side of the internet and down the other and can't find any pictures of these gages. I tried to find info on Balinese streamgages, but the best I could find was that many years ago a few gages were installed but no readings were ever taken. I don't know if these are the same gages.

Speaking of surprises, nowhere was it advertised that there's a long stretch of the Ayung's banks that are carved by local artists, commissioned a couple years ago by a resort on the hill. Google turned up a photo of the artists in action:

The carvings are finished and here's a selection of some others' photos from the web

It goes on forever and has a baffling level of detail.

I did get a chance to stand under a waterfall:

If you feel that your job is difficult, consider the life of this lady, carrying dozens of wet life vests at a time on her head up hundreds of stairs.

Bali to the highlands

On the flight from Perth to Indonesia, we saw some great water features in Western Australia. There were many circular depressions filled with water, near the rivers. I had seen these on Google Earth before but didn't quite know what they were. I'm still not sure I know why they happen. 

Water quality seems a major concern in Indonesia and you'll likely see signs like this, even in relatively posh resorts.  

On our second day we went from Denpasar to Ubud to see a cremation ceremony for a member of the royal family. The driver was happily obliging although somewhat confused by my excited arm flapping and insistence to stop whenever we crossed over a bridge. Many of the rivers in the rural areas are in canyons and are pretty.  

It's the dry season right now so the water is low. 

 As we got closer to Ubud though, a few of the rivers on the outskirts had some trash but this was more the exception than the rule.

CSIRO floreat raingages

After talking with the folks at CSIRO Floreat (Perth), I took a stroll around campus. These are restricted sites, so I always recommend checking in with reception before visiting. These campuses though are usually a fascinating mix of green-spaces like the below...

next to rusty drums full of chemicals, windowless buildings labeled "Danger quarantine", experimental greenhouses and so on.

In a back lot I came across this little weather station. The wind direction vane looked like it had seen better days (the bent thing on the right) but the wind speed cups (the bowls on the left) where whirring away as the wind picked up. It then started spitting rain, coming down in horizontal sheets. I had to hide in a shelter for a dirt pile to keep dry. Soon after, the driveways started forming small streams.

On the other side of campus, my eyes just about fell out of my head when I came across this:

 I used to have something like this at my house in Portland. The inner ring fills up with rain pouring down the funnel. The black top comes off and the tube can be lifted out, read, emptied and put back in. If the rain gets very heavy, the water pours over into the outer ring. It was neat.


Sorry, I meant, "it was neat... times NINE!" There were nine gages at three different heights set up in a set of triangles.

In Portland I similarly had two gages next to eachother and would read both and compare them. It was surprising how different they could be, even just a couple feet apart. 

CSIRO floreat and Perths' water woes

Before leaving for Indonesia, I had a chance to spend at day at CSIRO in Perth/Floreat with Kevin Petrone and Richard Silberstein. They both work on a range of topics, but perhaps most in the news is their work related to this now famous chart of Perth water supply inflow. The data and chart are from the water suppliers and Kevin and Richard's group's work is in understanding what's going on. Each bar is a year's flow and the higher bars are the wetter years. The average flow for the last 5 years has been about 1/6th what it was from 1911-1974.

They believe that after dry years, the groundwater levels drop, making it harder to get good runoff later on, even if the rainfall comes up to normal. Indeed, the rainfall plot does not look nearly as bad as the runoff graph.

You might think of it this way. You have a bank account and there's income and expenses. When your balance gets low, the bank starts charging you fees. These fees keep knocking you below the minimum balance threshold. So you get more fees and keep falling behind. It's possible to break the cycle, but it takes a pay rise or maybe hitting the lottery.

Similarly, in a few years rainfall was low so the water table dropped. That makes it harder to get water from the landscape to the river. So then there's less runoff and the soils around the rivers dry out. Then the water table drops further and even if there's more rain, there's not as much of a connection between the landscape and the river.