Indonesia 2025. Day 12. The Riam Kanan reservoir

Yesterday was a good cultural day, but today I need to see green, mountains, and water so we headed out of the city back to the foothills of the Meratus mountain range. The thing is, to get there you have to cross 50 km of city and I was reminded that Indonesia is the fourth largest population in the world (after India, China, and the United States). There are 200 million people in this country, and for a moment there they all seemed to be on the road to the Meratus Geopark.

We passed a couple of quarries where they extract serpentinite by the simple process of undermining the 50 m slope until it fails in a spectacular rock avalanche (no stinking benches in this method of mining), after which the job of the miners is to separate the blocks by size to sell as foundation stone.

We also saw a beautiful outcrop along a small mountain stream, where the water breaks into foaming rivulets and feeds a string of swimming holes that are the delight of the local children. For us the big thing is that the brook runs over blue schists, which is a really rare type of rock formed by UHP metamorphism (ultra high pressure metamorphism) along subduction zones. The rock contains multiple needles of the blue amphibole barroisite, but is not blue itself (maybe a dirty brownish blue). Details, details. The cool fact is that it is a real uncommon rock.

Form there we went to the small concrete dam that impounds the very large Riam Kanan reservoir. The reservoir reminds me of Lake Don Pedro with is many extensions parallel to the regional foliation of the mountains. I am not sure what is its main use. There is a small hydrolectric plant (three turbines, each of which can generate 10 MW, but they are not always on line), but I don't see any irrigation canals coming out of it. Rumor has it that it was conceived as a big hydroelectric project of "the New Order" during the term of the second president Suharto, but time went by and now folks come to visit for recreation and camping. There are all sorts of small villages that grew along the shores, and the views of so much water are truly spectacular.

Despite it being a hot day, Irvan and I climbed to the equivalent of the Hollywood sign to enjoy the view and feel that we were getting some exercise. Once on top, however, Irvan tried to convince me to call a motorcycle taxi to bring us down because he was "hungry and tired". "How many steps have you walked today?, I retorted, and after looking at his cell phone (the guy is a virtuoso of a thousand apps) he came back with 3,500 steps. "What? Don't you know you have to walk 10,000 steps every day?" Rather grumpily he started walking down the path, and his mood didn't improve when a moto-taxi swept past us carrying a china-doll of a girl who had been extensively photographed against the backdrop of the lake by her adoring boyfriend.

Once we got down Irvan was suddenly not hungry, so we ended having a late lunch on our way back to our hotel, in a typical restaurant of the region that offered delicious grilled fish in sweet and gooey barbecue sauce.