Leave Taipei 台北 Friday evening by train to spend the night in Xincheng 新城 closer to the trail head.
Saturday morning we drive in 14 km from Heping 和平 up the Heping forest road 和平林道 (or Dazhuoshui forest road 大濁水林道) along the south side of the Heping River 和平溪 (or Dazhuoshui river 大濁水溪) which marks the border between Hualien and Yilan 宜蘭 counties. Passing beyond all the cement quarrying industry of Taiwan Cement we arrive at the Dongbu Power Plant Bihai Branch 東部發電廠 碧海機組 where the road is blocked by a gate. An aborigine guard comes out to inform us that passage beyond the gate requires approval from the Taiwan Power office in Hualien 花蓮 despite the mountain entry permits 入山許可證 we hold issued by the county police authorities. The Nanxi Dam 南溪壩, another 10 odd kilometers further in on the Heping forest road, at an altitude of 545 meters, on the Heping South River 和平南溪 creates a reservoir with a capacity of 635,000 m3 supplying water to the turbines at Bihai after dropping 445 meters. Surveying for the dam began in 1996. Construction started in 2001 and the dam began operation in December of 2011 after project costs of NT$16.5 billion (US$ 569 million). An intake valve connects the dam at 545 meters altitude with a 6,549 meter long headrace tunnel to Bihai Power Plant at an altitude of 100 meters where a vertical Pelton turbine generates 61.2 MW of power. The plant generates 237 GWh annually. 18 hours of daily water capture and storage generate enough electricity to supply six hours of peak load in the region.
We turn around and drive almost a kilometer back down the valley where we can drive down to the river and drive back up the sandy packed truck track along the river bank almost back up to the level of the power plant again. Packing up to hike we quickly discover that the river is impossible to cross here and we hike back downstream well below our parking spot before we find a place where we can cross to the north side of the Heping River 和平溪. We find a gravel industry road on the north bank that cuts off a little over a kilometer of tracing along the river. We have lost hours of daylight to negotiating the beginning of the hike.
Various records of the road indicate that the road went on for 50 to 60 kilometers following along south of Heping South Stream 和平南溪. Some records suggest military function. There are also records of aborigine settlements which don't seem to exist anymore. The Nanxi Dam 南溪壩 was built in a remote area and most of the material and construction material was brought to the site with helicopters. Dam construction required the building out of 28 kilometers of road, 13 tunnels and 15 bridges. Excavation was limited to protect the integrity of the landscape. Though we were not permitted to enter the road, we clearly see the road in the contour of the mountain slopes south of us until we leave the south branch of the river to trace Heping North Stream 和平北溪.
Taiwan is a 36,000 square kilometer subtropical island. Steep mountains over 1,000 meters in elevation cover 32% of the island; hills and terraces between 100 meters and 1,000 meters make up 31%; while alluvial plains below 100 meters, where most human activity is concentrated, cover the remaining 37%. The northeast monsoon prevails from October through March. Typhoons and thunderstorms bring in abundant rainfall from May through September. The mountains are dominated by fractured, and deeply weathered metamorphic and sedimentary rock. Intense rainfall and flow of flood water causes severe erosion which is compounded by earthquakes which undermine the stability of the slopes. The rivers of the island are short and steep, becoming torrential during heavy storms. About 78 % of annual precipitation falls from May through October, with most water delivered by storms and typhoons. Average annual rainfall is 2,515 millimeters or 90.5 billion cubic meters. Average annual runoff is 66.8 billion cubic meters, of which only 23 % or about 15.4 billion cubic meters, are available for the use during the dry period from October through April. Annual pumped groundwater is estimated at 7.1 billion cubic meters.
We arrive at the Heping North Stream 和平北溪 confluence at noon and are off again after a lunch break at 1 PM.
The Heping North river 和平北溪, Heping South river 和平南溪 Feng stream 楓溪 combined drain a 561 km2 watershed through the 48.2 km long river system originating from headwaters at Nanhuda mountain 南湖大山 at an elevation of 3,740 m in the central mountain range 中央山脈 flowing across Nanao township of Yilan county 宜蘭縣南澳鄉 and Xiulin township of Hualien counties 花蓮縣秀林鄉 before disgorging into the Pacific ocean on the island's east coast.
We tracked corresponding river height and rainfall at Bihai to gauge the possibility and safety of getting through the canyons into the upper reaches of Heping North stream 和平北溪. The Heping river system 和平溪水系 is administered by the First River Management Office 第一河川局 of the Water Resources Agency 水利署 under the Ministry of Economic Affairs 經濟部. The bureau operates Xinengbu 希能埔 river water level measuring station in Heping Village 和平村. Rainfall is measured at Taiwan Power Corporation Dongbu Power Plant Bihai Branch 秀林鄉臺電公司東部發電廠碧海機組廠. The CWB also maintains a comprehensive library of annual almanacs of the rainfall, flow and silting of all of the islands watersheds
After a 5 hour, 20 km trace from the Heping river confluence, with many challenging crossings we arrive at our base camp destination at Buxiaowan stream 布蕭丸溪 just at nightfall. Our overall elevation climb today is from 100 m to 350 m. Our camp site is on high bluffs of sediment pushed up in recent storm drainage where the Buxiaowan stream 布蕭丸溪 flows into Heping North Stream 和平北溪 in the northeast corner of a vast washed out bend in the main river. Our original itinerary had us dropping or full packs here and tracing up the Buxiaowan stream 布蕭丸溪 another 2.3 km in the late afternoon with light packs north to the confluence with Liuxing stream 流興溪 where Buxiaowan hot springs 布蕭丸 was last reported. But we are too late for that. We look around our camp for signs of Dazhuoshui 大濁水 hot springs, but the whole landscape has been drastically resculpted by recent storms.
There are several records of natural wild hot springs on branches of Heping North stream 和平北溪. The information from different sources is inconsistent, including naming. Storms may have covered springs or revealed new ones. So a survey is required.
With limited time, we decide that Mohen stream 莫很溪 is the more interesting option to explore. We leave our camp with light packs at 7 AM deciding that we need to be back by 11 AM in order to be able to get back out to Heping before dark. Leaving the vast wash in the bend of the river at our camp at Buxiaowan 布蕭丸, the stream passes through a short slot where we visit a little bat cave before the river bed opens again into another vast wash of sediment banks at the Mohen stream 莫很溪 confluence.
We turn around in sight of a landslide upstream on Mohen stream 莫很溪 which looks to be the beginning of a second slot canyon. Returning at 8:30 will allow us enough time to get back to our camp and walk out back out to Heping by the end of the day. We saw flags in the direction of the Mohen peninsula walk over by Nick was unable to follow the trail.
We pack up for the hike out.
As we take our final rest back at the confluence with Heping south stream we see the first other people we have seen on our trip far on the opposite bank of the river. They are traveling downstream parallel to us with a dog. One of them crosses to speak with us and asks not to take any photos of them. We notice that they are floating a large log downstream. The urge us to hurry to get down and across before the spillway releases. We continue travelling downstream parallel to them watching them float their giant log. As we approach our parked car we notice that a blue truck has come down to meet the men in the evening dusk to collect the log.