Hell or High Water: China’s Historic Wooden Bridges in Danger
On Aug. 6, the 900-year-old Wan’an Bridge in Pingnan County, a locality of Ningde City in the coastal Fujian province, was destroyed when it suddenly burst into flames.
A national-level protected monument, Wan’an was a “wooden arch corridor bridge,” which for centuries was an ancient architectural calling card for the region. In the fire, five of its six spans were completely destroyed. While investigations into the incident are still ongoing, all that remains now is part of the easternmost span’s corridor and roof.
Videos of the bridge ablaze quickly trended on social media platforms the next day. For Wan’an was one of a kind: 98.2 meters long and 4.7 meters wide, it was first constructed in the Song dynasty (960-1279), and was the longest wooden arch corridor bridge left standing in China.
Though its significance eludes many, wooden arch bridges are revered among Chinese architects and conservationists, and have garnered a reputation as “living fossils” and “legacy embodiments of ancient civil engineering concepts.” In Fujian and Zhejiang provinces, there are still more than a hundred similar bridges.
Amid a wave of enthusiasm from the local population for new wooden arch bridges, the traditional techniques behind their construction have well and truly been revived, but the protection of the ancient structures themselves still has much room for improvement.
Currently, China’s approach to the protection of national heritage sites prioritizes “conservation and rescuing endangered structures before all else” — but to keep these legacy structures alive, preventative conservation is key.
Few experts, however, had imagined that such architectural marvels would gain public attention in such a tragic fashion.
Myth no more
Though many people have perhaps never heard of wooden arch bridges, the Bianshui Rainbow Bridge in Kaifeng in the central Henan province, featured on the Song scroll painting “Along the River on Qingming Festival,” a national treasure, is quite famous and closely resembles this type of structure.
Not a single nail or rivet is used and all components fit together thanks to mortise and tenon joints — where one piece (tenon) slots or fits into another (mortise).
For some time, the intricate design and construction of the Rainbow Bridge were considered a product of the painter’s rich imagination. At least until the late 1970s, when scholars discovered wooden arch bridges in the mountains of Zhejiang and Fujian provinces.
Dai Zhijian, a professor at the Architecture and Civil Engineering School of Xiamen University who has long studied these bridges, believes arch bridges are the most technically delicate type of wooden bridge in Chinese history.
The bridge’s construction uses the technique of bianliang (literally “interwoven beams”), in which two sets of beams interlock to form a stable arch. One set has three long beams of timber arched across a span, while the other comprises five slightly shorter beams that alternate among the first set, forming an ancillary arch.
Rather than being held together with metal hardware, horizontal and vertical beams are connected at their intersections using traditional carpentry joints resembling mortises and tenons.
Due to their structural characteristics, the beams carry a significant amount of upward pressure that makes them susceptible to collapsing. Therefore, roofs were often added to weigh them down, hence the term “corridor bridges.” They are usually 20 to 40 meters long.
Most of these more than 100 structures are located within a small region of no more than 200 kilometers from north to south, spanning the counties of Pingnan, Shouning, and Zhouning in Fujian; as well as Taishun and Qingyuan in Zhejiang.
It’s why they are also called “Minzhe wooden arch bridges,” with Minzhe being a contraction of Fujian and Zhejiang in Chinese.
Technically, restoring Wan’an isn’t a very difficult feat. Deputy County Mayor of Pingnan Li Zhangtong said in an interview with The Paper that archives of the bridge are suitably comprehensive.
Add to that the collaboration of the local “inheritors of the national intangible cultural heritage,” and the bridge’s restoration looks hopeful. However, the historical value will inevitably be affected.
In 2003 and 2004, Zhejiang and Fujian separately applied for world cultural heritage status for wooden arch bridges, both to no avail. In 2012, seven counties in both provinces succeeded in getting 22 “Minzhe wooden arch bridges” included in a list of sites that China intends to submit to UNESCO for world cultural heritage status.
Of the three in Pingnan, collectively referred to as Baiqianwan (“Hundred, Thousand, Ten-Thousand,” the first characters of each bridge’s name), only Wan’an and Qiansheng made the list. The third, Baixiang, burned down in 2006.
In 2011, however, Baixiang was rebuilt using traditional techniques for “authentic restoration,” with the help of individuals such as Huang Chuncai, a third-generation bridge craftsman. But it was no longer eligible for nomination.
Beginning 2020, UNESCO introduced a limit of “one per country per year” for cultural heritage applications. There are currently dozens of sites on China’s application waiting list. It may be a few decades before these wooden arch bridges can be submitted for consideration.
For China’s ancient structures, the threat of floods and fires has always posed a significant challenge.
Research by architectural scholar Liu Yan on wooden arch bridges found that they were typically reconstructed once every 50-100 years due to water and fire damage. Wan’an itself is an example.
In 2016, a total of nine bridges in Zhejiang and Fujian were destroyed in one go in the flooding caused by Typhoon Meranti. Among those ruined were the Xuezhai and Wenxing Bridges in Zhejiang’s Taishun County — both classified Major Historical and Cultural Sites protected at the National Level.
According to Dai, due to their lack of metal hardware, if the water level rises beyond a certain point, the bridge becomes buoyant, and thus the beams disconnect.
Hu Miao, a “national representative inheritor” of the traditional construction techniques used in wooden arch bridges, reportedly witnessed such an event. “We fear it will be swept away like a raft the moment the river swells,” he says.
Hu underscores that every time the rain gets worse, whether day or night, he and some heritage preservation officials keep watch over the bridges. If necessary, they dismantle some of the bridges’ components and wait until the river settles before rejoining them.
If some components get swept away, a salvage effort usually follows. Even if they have to be retired, they can still act as references for restoration.
When the corridor bridges of Taishun were swept away in 2016, the county government issued an urgent announcement: anyone who discovers a component should — provided that it is safe to do so — secure them. Eventually, they were able to recover over 90% of what was lost.
Dai believes that the ever more frequent destruction by flooding in recent years is in part due to water conservancy projects. Newly built reservoirs and similar projects have raised water levels. For these bridges, he says, “Conservancy and conservation can be at loggerheads.”
But for ancient wooden structures, fire is even more disastrous. In a huge fire in 2021, 104 houses were gutted in Cangyuan County in the southwestern Yunnan province, wiping out almost an entire village.
Wooden arch bridges aren’t just vestiges of the past — they’re still part of daily local life. People like to cool off, chat, and smoke in the shade of those roofs. Firecrackers can also be seen on holidays. During the 2001 Spring Festival, Wan’an was almost destroyed by a fire caused by a haywire cracker.
Corridor bridges offer a spiritual space where locals observe folk beliefs. People set up shrines for ancestors and deities, and burn copious amounts of incense, especially on holidays.
In 2005, the Meichong Bridge in Zhejiang’s Jingning County was destroyed in a blaze caused by a joss stick that a villager inserted between the boards of the bridge walkway during the Dragon Boat Festival.
According to Liu Yan, this custom didn’t pose much of a risk throughout history because ancient joss sticks weren’t as powerful and would not likely have set a bridge afire. But now, joss sticks with synthesized oxidizers make them much more dangerous.
Relevant authorities took action. Dai says that the majority of wooden arch bridges in Zhejiang were officially rid of shrines several years ago. And since August 2021, Tangshun banned the use of flammable items such as firecrackers and joss sticks on these bridges.
But in many other regions, fire safety management is far from adequate. Cultural conservation expert and former Deputy Dean at the Chinese Academy of Cultural Heritage Zhan Changfa says that though it’s a fact that ancient wooden structures are susceptible to water and fire damage, what’s more important is ascertaining whether any preventative measures were put in place.
For example, Wan’an was listed as a heritage site at the national level in 2006. Every year, the National Cultural Heritage Administration earmarks fire safety funds for it. But the fire that consumed it came with no warning.
Then and now
Dai believes that significant improvements have been made in the past few years in conservation, and that governments and villagers do appreciate these sites more. But in the absence of sustained, routine, and comprehensive protection, many ancient bridges are fading away.
At one point, traditional building techniques were at risk of dying out; for more than three decades since 1969, bridge craftsman Huang Chuncai worked on no bridges.
According to architectural scholar Liu Yan, by the end of the 1970s, there were only three groups of traditional bridge craftsmen left in Fujian, who’d been imparting their skills for more than three generations, including Huang’s family.
It was not until 2003 that the National Cultural Heritage Administration organized a survey into the wooden arch bridges of Pingnan and took note of the craft. That’s when Huang’s skills were brought out of retirement.
In 2009, “Traditional design and practices for building Chinese wooden arch bridges” was included on UNESCO’s List of Intangible Cultural Heritage in Need of Urgent Safeguarding. Four people, including Huang, became representatives of this craft and started to take apprentices.
After the economy took off in recent years, locals found the means to raise money for new bridges, as it’s believed to improve fengshui, or geomancy. In this practice, bridges are supposed to “lock in water” — thus, by building a bridge just upstream from where they live, one can prevent fortunes from “flowing away,” generally keep disaster at bay and bless the family with more babies.
Dai explains: “Everyone chips in, from a couple hundred yuan to several hundred thousand yuan.”
To this day, villagers electing boards to raise money for bridges remains customary in the mountains of Fujian and Zhejiang. Dai says that for locals, constructing new bridges is considered honorable, whereas preserving old ones brings nothing. He’s even seen a new bridge that is purely ornamental and doesn’t benefit transportation in any way — one end leads nowhere.
Liu Yan’s research also mentions that two of the wooden arch bridges restored in Shengshuitang village in Zhejiang are located right next to concrete bridges.
The project organizers explained that it was as much about fengshui, as charitable intentions. This facelift even extended to the village’s name. In the past, it was called Shatang, or “Sandy Pond,” which was deemed unappealing as a sandy pond is hostile to life such as fish. So they changed it to Shengshuitang, or “water conservation pond.”
As such, the market provides craftsmen like Huang with a stable source of work. Dai estimates that 20 to 30-odd wooden bridges have been built in Fujian in the past few years.
This is undoubtedly a good thing to preserve intangible heritage. The craft is no longer endangered, but the bridges themselves — the ancient ones, not the new imitations — still are.
For local governments, the incentives are also clear. Repairing ancient bridges and building imitations both require money, but the latter can aid tourism. Dai believes this is “building fake antiques, which means little for the genuine artifacts.”
Meanwhile, Zhan, the former Deputy Dean at the Chinese Academy of Cultural Heritage, points out the recent destruction of Wan’an Bridge highlights the dire lack of warning mechanisms and preventative protection measures, which currently are supposed to be the very core of conservation.
In the field of ancient architecture, closely monitoring a building’s state and tending to its daily maintenance are paramount.
According to Zhan, China still has a long way to go on sustainable planning for conservation work. Currently, daily maintenance remains elusive for most sites. What gets trumpeted instead, is “rescuing endangered structures before all else,” which in reality often means allowing structures to fall into disrepute and only intervene at the last minute.
Says Zhan: “Rescue initiatives are like sending ‘sick’ artifacts to the ER: we resuscitate them, but the problem doesn’t go away. How to conserve cultural artifacts is a matter that we urgently need to discuss.”
Reporter: Zhang Tianqi.
A version of this article originally appeared in The Intellectual. It has been translated and edited for brevity and clarity, and is published here with permission.
Translators: Lewis Wright; editors: Zhi Yu and Apurva.
(Header image: The wreckage of Wan’an Bridge, Aug. 7, 2022. VCG)