2012 / 9月
據《淡水廳誌》記載，最早的埤圳系統在今八德霄裡一帶，由漢人與平埔族共同開闢，包括4口陂塘和圳道，灌溉6 個庄的農田，完成後水權由原住民佃戶分配6 成，漢人佃戶分配4成。
Coral Lee /photos courtesy of Jimmy Lin /tr. by Scott Williams
Jets slowly descend into Taoyuan International Airport, offering passengers fleeting glimpses of flickering mirror-like ponds on the ground below. The ponds, which dot the entire Taoyuan Tableland, are irrigation works that were built by our ancestors as they carved farmland from the wilderness. Closely packed over a vast stretch of the plateau, these works give Taoyuan a landscape like few other places on Earth.
Over the last 30 years, more than 10,000 of Taoyuan’s irrigation ponds have been filled in to support urban and commercial development. Only 2,800 remain, slowly gaining the attention and care of the public under the twin umbrellas of wetlands conservation and a campaign to include them on the World Heritage register.
What does the mention of Taoyuan bring to mind? Factories? Dense population? The international airport? Patchwork fields?
Few people realize that Taoyuan has its own unique rural scenery. Its undulating plateau, so different from the broad, flat Jianan and Lanyang Plains, is dotted with rice paddies. Surprises are frequent when you travel its canal-lined roads. An elegant ancestral hall in the middle of a field might stir thoughts of the distant past. You may catch a glimpse of an old brick building standing beside a byway, or of someone laundering clothes in a pool under a large tree. At higher elevations, you’ll find irrigation ponds shimmering in cool breezes on hot summer days.
While rice paddies elsewhere in Taiwan get their water from streams or irrigation works linked to large reservoirs, those on the Taoyuan Tableland still rely on 700-some irrigation ponds. Linked to the Taoyuan and Shimen Canals to form a web-like irrigation system, these ponds provide the water for the paddies in a dozen-odd townships, including Dayuan, Luzhu, Bade, Yangmei, and Xinwu.Tracing the source
But 300-odd years ago, the vast Taoyuan Tableland was a wilderness without a single pond. The plateau’s topography is what allowed the pond system to grow to its present scale.
Much of Taoyuan is, effectively, the alluvial fan of the Dahan River (formerly known as the Shimen River), which once flowed from Mt. Shimen straight to the sea. But 30,000 years ago a tectonic shift caused the Taipei area to abruptly lose 200 meters of elevation. This drew the Dahan River northward, where it was captured by the Danshui River system. As a consequence, two downstream rivers—the Guanyin River and the Daku River—lost their headwaters and became short “beheaded streams.” Because these beheaded streams are almost completely without water in the dry season and often flood during heavy rains, they are useless for irrigation.
Though the plateau has springs, they don’t carry enough water for irrigation. The idea of digging pools to store rainwater emerged during the reign of Emperor Qianlong (1736–1795) in the Qing Dynasty.
According to official annals, the earliest of the irrigation pond systems was located in what is now the Xiaoli area of Bade City. Built by ethnic Chinese and lowland Aborigines, the system included four ponds and irrigation channels providing water to the fields of six property owners. The completed system delivered 60% of its water to Aboriginal tenant farmers, and 40% to ethnic Chinese tenant farmers.
Chang Wen-liang, a professor with the Department of Bioenvironmental Systems Engineering at National Taiwan University, says that our ancestors made very intelligent use of the Taoyuan Tableland’s topography—high in the west, low in the east—building ponds at higher elevations and allowing gravity to draw the water downhill. They also dug storage ponds at lower elevations, eventually building more than 150 ponds in the area. “It was a beautiful piece of irrigation work,” says Chang.Intelligent water systems
Following a severe drought during the Japanese era, the Japanese government built intakes at Shimen to draw water from the Dahan River, dug the Taoyuan Canal as a major irrigation channel, and regularized irrigation volumes by consolidating more than 2,000 of the county’s scattered, variously sized ponds into just 200-some.
Yoichi Hatta, a Japanese hydraulic engineer, designed and oversaw the construction of the Taoyuan Canal. Hatta did such excellent work on the project that his commanding officer reassigned him before its completion, putting him in charge of the even more challenging Jianan Canal and Wushantou Reservoir project. When completed in 1928, the Taoyuan Canal provided enough water to support the conversion into rice paddies of 20,000 hectares of land in the northern part of the plateau.
Following Taiwan’s retrocession, the ROC government in 1947 began work on the Guangfu Canal, extending the Taoyuan Canal irrigation district to the southwest. After completing the Shimen Reservoir, the government went on to build the Shimen Canal to the south of the Taoyuan Canal in 1963, linking more than 400 irrigation ponds in the southern part of the county to the reservoir.
The irrigation maps put out by Taoyuan’s various irrigation associations show that the main arteries of the Taoyuan, Guangfu, and Shimen Canals traverse the plateau from east to west, with transverses flowing northwards from the main channels into lower-elevation land, and then spreading out into a dense network connecting variously sized ponds. Roughly half of the water in the irrigation system is rainwater. The other half comes from the Shimen Reservoir. The system made Taoyuan the “rice basket” of northern Taiwan until the 1980s.
“The pond systems use gravity to transport water to each of the irrigation districts,” says Monica Kuo, a professor of landscape architecture at Chinese Culture University who is promoting the inclusion of the irrigation works on the World Heritage register. “They follow the land. The process doesn’t require pumps or waterwheels of the sort they use to move water in the Netherlands. The ponds are intelligent manmade artifacts worth preserving.”A family’s story
“The ponds don’t only provide irrigation. Each pond is a living, productive ecosystem,” says Chen Chie-peng, a professor with the Department of Interior Design at Chung Yuan Christian University. Chen, who began studying Taoyuan’s ponds in 2003, says that Taiwan’s early residents organized families and communities to dig the irrigation channels they needed to survive on the dry, windy plateau. The completed irrigation works turned previously barren land into fertile fields that allowed for more prosperous lives, the construction of temples, and the putting down of roots. The ponds chart the rise and fall of families, reveal aspects of ethnic cultures, and have historical implications.
For example, the Fanjiang Ancestral Hall and nearby Xinwu Pond in Taoyuan’s Xinwu Township are living reminders of the development of a Hakka farmstead.
The Fanjiang clan came to Taiwan from Huizhou, Guangdong Province during the Emperor Qianlong’s reign. In those days, northern Taiwan was dominated by immigrants from Fujian Province, obliging the Fanjiangs to settle in the wilds of Taoyuan. After receiving permission to clear and cultivate land, they worked their way inland from the coast, gradually adding to their holdings. More than 100 years of hard labor converted wilderness into fertile fields, attracting other pioneers.
When the Fanjiang clan completed their magnificent ancestral hall in 1855, they caused a sensation in the township. Residents brought their friends to “come see the new building.” Over time, the area even came to be called “new building” (“xinwu”), a name it bears to the present day.
The ponds are indelibly imprinted upon the childhood memories of many Taoyuan natives.
Qiu Xianda, head of the Irrigation Association’s Bade office, will never forget the fishing, pond crossing, and water fights he enjoyed as a boy. And he fondly recalls the annual “scooping the pond” festivities held prior to the Lunar New Year.
He explains that as winter approached, pond owners would let their ponds go almost dry. When water remained only in the deeper area at the center, locals would begin “scooping the pond.” Men would net the larger fish, then the women and children would catch any small fish, shrimp and crabs the men had missed and toss them into bags. The idea was to prevent them from dying from the cold in the pond. The kids had a great time, and loved the big meals that followed, making it one of the most anticipated events of the year.From resplendent to dilapidated
But the joys of the agrarian lifestyle couldn’t compete with the attractions of city life and the prospect of industrial and commercial development. After the completion of the Shimen Reservoir, the ponds became superfluous. In the 1980s, factories began moving to Taoyuan as well. As the demand for land rose, farms shrank and ponds disappeared.
Since the 1970s, a myriad of factors have contributed to the filling in of ponds, from the construction of the airport and the resettlement of military dependents to urban planning measures that rezoned nearby land and built schools, hospitals, industrial parks, and government offices. Worse, industrial runoff has polluted many of the remaining ponds and caused farmers to let their land go idle. As a result, Taoyuan’s irrigation ponds now cover just 2,900 hectares, down from 9,000 at their peak.
Today, the Taoyuan and Shimen Irrigation Associations control 700-some ponds. In addition to managing irrigation, the associations also rent ponds to aquaculturalists who use them to raise fish and shrimp. The other 2,000-odd ponds are owned either by clans or individuals. Most of these are used for aquaculture, shrimp fishing, or adjustments to the fengshui of personal residences. In recent years, local governments and irrigation associations have responded to the burgeoning interest in the ponds by sprucing some of them up for use as recreation areas. Zhongli City’s Qingtan Park and Bade City’s Taoyuan Bade Eco Pond Park are cases in point.
But there are also many “wild” ponds. Largely uncared for, these have evolved into ecological treasures and educational resources.
Pond 731 in Yangmei’s Gaorong ward is one such. Just 1.1 hectares in area, it was originally dug by the Taiwan Water Corporation to provide water in the event of the failure of the Shimen Reservoir. After many years of maintaining the pond without ever putting it to use, the TWC allowed the sluice gate to fall into disrepair. With that, the pond ceased to function as a water-storage pool and, over time, evolved into a shallow marsh that has become home to numerous wild animals and plants.An eco-paradise
When a team from the Taipei Zoo carried out a long-term study of Pond 731, it found many rare and protected species living there, including the Taipei frog, the yellow pond turtle, and the plumbeous water snake. The team also found 34 species of dragon- and damselflies, a figure that amounts to a quarter of the species in Taiwan, as well as the largest collection of pied paddy skimmers seen in Taiwan.
Designated a conservation area by the Council of Agriculture in early 2012, the pond is now Taiwan’s smallest wildlife preserve.
The Taoyuan branch of the Society of Wilderness has been organizing volunteers to help maintain the ponds for years. “Neglected ‘wild’ ponds become marshy very quickly,” says Zhang Yanqi, head of SoW’s Taoyuan office. He explains that pioneer species such as swamp rice grass and swamp panic often colonize the ponds, and that invasive fish species such as the common snakehead and tilapia are very persistent as well. If the ponds are to provide living space for indigenous species, people must make the effort to keep them free of invasive species.
In addition to providing homes to plants and animals, the ponds are also likely to benefit human beings in this era of extreme climatic events. When torrential rains fall, pond systems act like a sponge, soaking up rainwater and channeling it underground. During droughts, that same groundwater can be a lifesaver.
Chen Chie-peng notes that even though the plateau should be less prone to floods than low-lying ground, the torrential rains of June 11, 2012 flooded some 900 hectares in Taoyuan. In fact, Taoyuan was one of the counties and municipalities that suffered the worst flooding from the storm. Kainan University, where the floodwater stood a foot deep, is built on one of the areas where irrigation ponds were filled in to make way for development.Crisis
Chen says that Taoyuan’s irrigation ponds have been collectively designated “national wetlands” by the Ministry of the Interior. But since they have not been individually designated, owners and property developers still have opportunities to manipulate their zoning.
Worryingly, while the legislature has speeded up its scrutiny of the proposed Wetlands Act, some landowners are eager to fill in “redundant” ponds before the act takes effect. Furthemore, the Rural Rejuvenation Act passed in 2010 allows 10% of rural land to be rezoned for development, and the pending Wetlands Act, in its current form, fails to designate ponds under 2,500 square meters in area for conservation. What this means is that a property owner who fills in a 2,500-square-meter pond can develop 250 square meters of that land. This situation is placing small ponds in jeopardy.
The Rural Rejuvenation Act also permits property owners to lump scattered holdings together to calculate their area. For example, an owner with five pieces of land totaling three hectares distributed across Taoyuan and Hsinchu is permitted to develop any 10% (about 3,000 square meters) of that total. As many of Taoyuan’s irrigation ponds are in locations that are attractive to developers, this is likely to result in the concentration of large amounts of new development in Taoyuan.
“Irrigation ponds have a significant, lasting value,” says Chen, who argues that we can do more than turn them into parks. He urges us to set our imaginations to work on rejuvenating the ponds, to seek ways to integrate them with everyday life in Taoyuan.
In 2007, Chen planned a “tour itinerary” for Xinwu Township, connecting 12 secondary canals in the Taoyuan Canal system, a number of ponds, and the Fanjiang Ancestral Hall into a recreation and tourism corridor. Unfortunately, the government department implementing the plan had concerns about public safety. By choosing not to open up all of the canals designated by the plan, it limited the effectiveness of the community reconstruction program.
Currently, nearly every primary school in Taoyuan’s many townships stands within one kilometer of an irrigation pond. If Taoyuan’s teachers were able to exploit their local pond resources, which are excellent tools for ecological education, the ponds would become more relevant to their communities.
“The ponds are Taoyuan’s bright spots,” says Chen, whose study of the ponds has taught him to love them. He even bought a home next to one, and often takes his child for walks around it. Chen spends his daily bicycle commute planning new and different canal routes highlighting the area’s diverse agricultural scenery.
Chen says that the ponds and canals integrate local history and culture with environmental education and sightseeing potential. If factored into urban planning and rural development programs, he believes they have the potential to change Taoyuan’s way of life and make the county a healthier and more sustainable place.