Another Sunday Trip To Tseng-wen Reservoir (曾文水庫)

I began last Saturday night with the intention of waking up early on the Sunday morning; events put paid to that hope. As it was, me and the girlfriend managed to get the dogs walked and get ourselves ready to leave at just after 9 a.m. I had fondled the idea of driving all the way up to Chiayi city via provincial highway three, but in the end we settled for Tseng-wen reservoir, as she hadn't been there since she was a child. We took the front entrance so that I could look at the construction for the new diversion tunnel to "Little Switzerland"...

Partial glimpse of the site looking upstream from the bridge immediately after the front entrance. It was a very bright, very hot day.

Overview of the scene; to the right the old weir and entrapment pen for the existing diversion tunnel built by Japanese engineer Yoichi Hatta, and to the left the signs of early stage construction for the new diversion tunnel, partially hidden by a clump of trees.

Close up on the existing weir and entrapment penstock.

Panorama overlooking the "shelf" behind the reservoir's three enormous tainter gates.

Finally, some English in the information signs - unfortunately, it was largely restricted to bland generalities except for the specific mention that the new sluiceway is expected to remove up to 21.1% of the sediments currently trapped behind the dam at the south end of the reservoir. 

More information in English - note the one about "enhancing public trust to the government". I'm quite sure the environmentalists will not see it that way and will do everything they can to discredit the project.

Back to Mandarin, with QR codes for your smartphone to read.

Plan of the new sluiceway in red, with the existing one in yellow.

Cross section of the new sluiceway design; the "elephant trunk" intake pipe and retaining shaft to the left of the main sluiceway and the expanded free-fall chamber to the right. This chart may be somewhat visually confusing in that the water level for the reservoir is shown as being just above the mouth for the elephant trunk intake pipe, when typically it will be much higher - I doubt I will ever see the intake pipe once it is installed. Once the water passes through the intake and into the main sluiceway itself, it will gain momentum due to the angle and distance of the sluiceway; in order to protect the river bed outside from erosion, the resulting energy of the water must be dissipated and that is the function of the expanded free-fall chamber (it is similar to the hydraulic jump and stilling bay at the end of the dam's three spillway concourses).

This box describes various dimensions of the new sluiceway tunnel and it's "elephant nose" intake design. These dimensions include the maximum and minimum elevation values for the center line of the tunnel, its' diameter and length, gradient; the diameter of the upper retaining shaft and the remote control operation of its gate; the length of the sluiceway tunnel itself after the water intake and retaining shaft and the length of the energy dissipation chamber toward the south end of the tunnel.

More details on the dimensions of the "elephant trunk" intake pipe. Again, the highest and lowest elevation values for its center line are given (195 meters and 175 meters respectively), along with the diameter (10 meters) and the overall length (56.1 meters).

A close-up cross section view of the elephant trunk intake pipe, retaining shaft and remote controlled tainter gate. In this image the elevation value given for the reservoir's water level is the maximum value before the spillway gates have to be opened (225 meters above sea level). You can see that, when the reservoir is full, the elephant trunk intake pipe will be some distance under water (perhaps as much as 30 meters).

An annotated google earth screenshot is included here illustrating the construction plan for the elephant trunk intake pipe; it is being built just south of Dapu and will be floated down the reservoir by barge to be fitted into the tunnel once the water level has been drawn down sufficiently to allow the operation to proceed. Probably this will take place sometime this winter, and I hope to be there to photograph the operation being carried out.

This chart details the modular construction method for each steel section of the elephant trunk intake pipe.

Myself feeding a poor stray, who really should have been curled up into a ball somewhere in the shade at this hour to keep out of the sun. She was placid and ate the beef jerky out of my hand with minimal fear. We looked for a container to give her our water, but the engineers in a nearby portcabin told us she already had a bowl of water there.

The view over the south end of the reservoir looking northward.

Ching-Yu waterfall (青雲瀑布), just off the Qingshan industry road. I have passed by this waterfall many times but never once found the time to go and swim and hang out there until now. Perhaps unsurprisingly, the access road has now been cordoned off by police ticker tape and a sign erected forbidding people to enter on account of one stupid girl almost drowning there earlier this year. Naturally, we ignored the stupid signs and went anyway. It's a beautiful place for a picnic and a swim as long as you don't get too close to the waterfall itself, obviously.

Phone picture taken by my girlfriend of myself standing on a rock in front of the waterfall looking up at the dark clouds that were beginning to arrive.

Another such phone picture of me swimming in the pool.

The "elephant trunk" intake pipe itself, now almost complete. I have been recording its gradual construction over the past year or so, since the work began.

One member of the Black Kites that dominate the area at the back and middle of Tseng-wen reservoir. I've never seen a single Crested Serpent Eagle here, but I've seen several at the south end of the reservoir so there is very likely a territorial separation or "agreement" of sorts in place whereby the Kites take the north end of the reservoir and the eagles take the south end of the reservoir.

I suspect this is an older bird due to the little gaps of missing feathers in both wings.

Two Kites in a dead tree overlooking a farm at the north end of the reservoir.

Close up on the top bird looking west toward the camera.

Checking over his shoulder...

Eyes forward again...

Looking to the right to make a final check...

Raising his arse in the air...

And plop! Making a "deposit".

Time to get a shift on.

Typical Kite shot; wings outstretched showing the slight bend in the middle of the wings, with flight feathers fully outstretched and triangular tail at full expansion.