The ubiquity of concrete and recovering constructing stone walls

The modern world depends on a lot of concrete but that comes at a cost. Here is a description of efforts to instead build with stone:

Photo by Miguel u00c1. Padriu00f1u00e1n on Pexels.com

In 2018, UNESCO inscribed dry stone walling as an Intangible Cultural Heritage of Humanity, stating that “the technique exemplifies a harmonious relationship between human beings and nature.” When building a dry stone wall, Kaneko told me, you have to work with the contours of the land and irregularities of each stone. John New, the chair of the West of Scotland Dry Stone Walling Association, told me that “when you’re building a stone wall, you become part of the environment. Brown hares will just come up and stop and watch you.” Deer too. Almost as soon as it’s built, a stone wall is inhabited by insects—a key indicator of biodiversity—and small animals such as voles, chipmunks, and wrens. In China, researchers have documented the remarkable diversity of plants thriving on ancient stone walls—even in urban environments.

In rocky regions around the world, groups are working to preserve and promote the craft of dry stone walling, touting the benefits to biodiversity and low carbon footprint. These are inherently local efforts because building with stone makes the most sense when it can be sourced locally. (In the past, farmers used stone unearthed while clearing the very fields they needed to terrace or fence.) In Scotland, for example, trucking in material for a stock fence from far away could cost upwards of $5,000, New said. The most ambitious recent dry-stone-walling projects, such as the multimillion-dollar effort to restore the stone walls of Italy’s Cinque Terre, are in service of historical preservation. But Stone Walls for Life, the EU-funded project organizing the Cinque Terre restoration effort, argues that the walls strengthen resilience to climate change, too, by improving drainage and preventing landslides. They plan to replicate this kind of undertaking around the EU.

In Japan, Kaneko told me, most of the people who still know how to build simple utilitarian stone walls are in their 80s. In the past, if a stone wall along a rice paddy or road collapsed, the community would gather to repair it. This collective experience was key. When I met him again at a Kyoto café (in the concrete Kyoto International Conference Center, near a concrete-encased river), Kaneko told me about a 1919 Journal of Engineering article that emphasized the importance of human skill and discretion rather than objective numbers in stone-wall building. Although perfecting the craft of stone walling takes a lifetime, Kaneko said that an amateur, with no formal engineering experience, can learn the basics in about four days. Through workshops all over the country, he and Sanada teach people to place stones with the long side angled down into the slope, to make sure that each large stone touches at least two others, and to fill behind the large stones with small rocks or gravel as they build. There have been attempts to standardize and mechanize dry stone walling, using, for example, software and a robotic excavator. But Kaneko says that in many cases, the sites where he works are too narrow or steep for a machine to access. To him, stone walling’s reliance on man power instead of machine power, and passed-down knowledge instead of equations, is part of its value. “I like the very wild dry stone walls,” he told me.

Embracing those qualities, though, requires trust and experience. In July, Kaneko traveled to the town of Genkai, on Japan’s Southern island of Kyushu, to repair the walls at Hamanoura Tanada, a scenic and historic site where nearly 300 small terraced rice paddies chisel the dramatic slopes above an inlet of the Genkai Sea. A few years ago, the town’s planning and commerce division invited Kaneko to teach five local construction companies how to build dry stone walls so they could preserve the traditional scenery. But even with that training, none of them was willing to take on rebuilding stone walls. It’s seen as a labor-intensive and risky job, Kaneko said. Companies that use concrete can reliably calculate the strength of their walls, but it’s nearly impossible to estimate the engineered strength of any particular dry stone wall. Although villages and private landowners can choose stone over concrete, there have been no mainstream attempts to return to dry stone walling for major new public-works projects in Japan, Kaneko told me. In the United States, most landscaping walls shorter than three or four feet don’t need to be permitted, Alan Kren, a structural engineer at Rutherford + Chekene, told me. To build stone walls on any larger scale would likely require new standards for using these old techniques.

Lots of potential connections between this and the move to modernity more broadly:

-New crafts and methodologies that people know and use while older techniques fade away.

-Technological and scientific progress in new materials but costs with which we have not fully reckoned.

-Lost community moments replaced by private activity.

-Local efforts are difficult to sustain given broader global and social pressures.

The march of concrete will go on while some advocate for other options. And perhaps at some point concrete will be replaced by another material and the techniques of using concrete could be lost.