Watersheds and Water Engineering

This week in Japan I visited two parks on Miyajima Island and gardens in Okayama and Takamatsu. These experiences have made me consider how water powerfully shapes landscapes and how humans use a variety of strategies to control the flow and movement of water.

Miyajima Island
Miyajima Island, or Shrine Island, is designated as one of Japan’s three most scenic spots; it is best known for the Itsukushima Shinto Shrine and its floating red O-Torri (or grand gate). The visitor guide pamphlet notes that Miyajima has “Places of historic interest, cultural assets and promenades full of the beauties of nature” and highlights the island’s “history and tradition, blue sea, mountains and greenery.”

Itsukushima Shrine, Miyajima, Japan

Itsukushima Shrine, Miyajima, Japan

The shrine is a powerful example of human engineering—it was constructed to respond to the changing tides. The shrine is built on pier structures so that the shrine appears to float over the water. The walking corridors are engineered with spaces between the floorboards to allow water at unusually high tides to rise up through the gaps and to allow rainwater to drain down through the gaps. At high tide the O-Torri appears to float, but at low tide it stands in mud and visitors can walk out to it.

O-Torri at low tide, Miyajima Island, Japan

O-Torri at low tide, Miyajima Island, Japan

The shrine has been located at the base of Mt. Misen, a watershed, since the sixth century and it was designated as a UNESCO world heritage site in 1996. Water drains from Mt. Misen into rivers on the mountain and then into the Seto Island Sea. In 1945 rain runoff from the Makurazaki typhoon carried debris down the Momijidani River and buried the shrine in 20,000+ cubic yards of dirt and sand. In 2004 the shrine was again damaged by another typhoon. These weather events are important reminders of the power of water to impact landscapes and human built structures.

Holly and I hiked to the top of Mt. Misen along the Momijidani Park walking trail and back down the mountain along the Omoto Park walking trail. Both the Momijidani and Omoto parks are located within Setonaikai National Park, a park that includes 3000 islands in the Seto Island Sea. The trails were very, very steep with hundreds of stone stairs. As I hiked the steep slopes I observed evidence of fallen trees and soil erosion caused by the movement of water.

Momijidani River, Erosion Control Works, Momijidani Park, Miyajima, Japan

Momijidani River, Erosion Control Works, Momijidani Park, Miyajima, Japan

After the 1945 typhoon that caused extensive damage to the shrine, Momijidani Park was redesigned to control erosion caused by significant water flow. In the re-design engineers hid concrete waterways, did not cut down trees, and sited stones from the site to re-direct water. The design is notable in the balance achieved between engineering excellence and preserving the “natural” beauty of the river.

Waterway, Omoto Park, Miyajima, Japan

Waterway, Omoto Park, Miyajima, Japan

At Omoto Park visitors see a different design approach. Here the waterway’s engineered design is visible in a concrete base with carefully placed stones, both within and along the channel. This waterway reminded me of the carefully designed water reservoir and texture pool at Cal Anderson Park in Seattle, Washington.

Ponds and Streams in Japanese Garden Design
Water is a significant landscape feature in many Japanese gardens; ponds are central to the garden design. As I have noted in previous blog posts, water is a preferred landscape feature for humans. Japanese gardens are intentionally designed with this human preference in mind.

Sawa-no-ike Pond, Korakuen Garden, Okayama, Japan

Sawa-no-ike Pond, Korakuen Garden, Okayama, Japan

Korakuen Garden in Okayama is designated as one of Japan’s three most beautiful gardens. Here visitors can view and walk around three ponds and the streams that join them. The Sawa-no-ike pond is the largest—visitors can view rice and lotus fields at one end and Japanese style residences at the other end. Thus the design integrates “nature” and “culture” at each end of the pond. The redirection of water from the Asahi River to run within the garden, and then to rejoin the river, has created the ponds and streams that are a primary feature of the garden’s design. Floods damaged this garden in 1934, as did bombing in 1945. Each time the garden has been restored using illustrations and written descriptions of the original design.

Nanko (South Pond) with Mt. Shiun in Background, Ritsurin Garden, Takamatsu, Japan

Nanko (South Pond) with Mt. Shiun in Background, Ritsurin Garden, Takamatsu, Japan

Ritsurin Garden in Takamatsu is another renowned strolling garden where ponds and hills are purposefully constructed to create a walking promenade that provides a variety of views. This garden is located at the base of the Mt. Shiun watershed. The mountain extends the views of the garden by providing “borrowed scenery.” The watershed is the source of the water that flows into the streams and ponds within the garden. Visitors can enjoy ceremonial tea in the Kikugetsu-tei teahouse while looking out to views of the South Pond as wasen, traditional Japanese wooden boats, float by. The teahouse is nestled between Mt. Shiun, the South Pond, and a crescent moon shaped bridge, demonstrating the intricate connections between nature and culture.

Seawalls
Takamatsu is a large port city like Tacoma, Washington. Ferries regularly leave the busy Takamatsu port for the many islands in the Seto Island Sea, just as ferries regularly transport people and goods from Tacoma to Vashon Island in Washington.

Seawall, Takamatsu, Japan

Seawall, Takamatsu, Japan

As I’ve walked along the Takamatsu pier, and piers on nearby Teshima and Ojijima Islands, I’ve noted the use of seawalls to protect built areas from the action of tides and waves. Seawalls are yet another engineering strategy, like erosion control and redirecting water, which humans have used to manipulate the flow of water and to control potential damage caused by tidal action.

Water and the Human Built Environment
Humans have used a variety of engineering strategies over the centuries to build structures near the sea and on mountains, to redirect the flow of water, and to control erosion and tidal action. Events like the flooding caused by typhoons and tsunamis are important reminders about the power of water to shape and re-shape landscapes. The Itsukushima Shrine and the Korakeun and Ritsurin gardens have been built, re-built, and modified for many centuries. These cultural/natural sites are evidence of the dynamic and ongoing relationship between the power of water and human engineering to create landscapes. As I visited parks and gardens, and considered the role of water and water control strategies in these environments, I was reminded of an essay I recently read about how the legacy of a site is shaped by nonhuman nature, human-designed water policies, and our collective history and memory about the significance of a site. In the essay entitled “Constructing Nature: The Legacy of Frederick Law Olmsted” Anne Whiston Spirn writes:

“Niagara Falls is shaped by water flowing, rocks falling, and trees growing, by artists and tourists, by journalists and landscape architects, engineers and workers who divert the water. Niagara is constructed through processes of nonhuman nature, through water use policies, paintings and postcards, memory and myth” (p. 98).

View from Itsukushima Shrine to O-Torri, Miyajima, Japan

View from Itsukushima Shrine to O-Torri, Miyajima, Japan

For more information about this research project read the Project Overview.

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Resources
Spirn, A.W. (1995). Constructing nature: The legacy of Frederick Law Olmsted. In William Cronon, W. (Ed) Uncommon ground: Toward reinventing nature. (pp. 91-113). New York: W. W. Norton & Company.

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Amy E. Ryken

Amy E. Ryken

Amy E. Ryken studies partnerships that foster connections between schools and community resources, such as museums and outdoor environments. She is particularly interested in a broad definition of learning that considers how people learn, in a wide range of settings and activities, over the life span.
Amy E. Ryken

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