Background. In the early 1990s, Three Gorges Project was launched on the upper reaches of the Yangtze River, which finally caused about 1.13 million people moving into new towns. Built in 1992, Yunyang is such a “Migrant Town”. Located on a triangular hillside zone where Yangtze River meets Pengxi River, it sits just aside the bank of Three Gorges Reservoir, whose annual vertical fluctuation is up to 30 meters. Began in 2014, landscape architects firstly completed the overall planning of 33-kilometer’s waterfront public space with a total area of 448 hectares (44% of which are located in the water-level fluctuation zone). Then, the design of the 10-kilometer waterfront space surrounding the city center was proposed, and was eventually completed in 2021.
Challenges and Objectives. Problems bothering Yunyang waterfront could be mainly listed as:
1. The shortage and low quality of public green space. Although the city’s existing waterfront has great spatial potential, it lacked reasonable planning and development. Several waterfront parks of various sizes were unattractive due to the outdated design and aging facilities.
2. The fragmentized and passive waterfront space. Waterfront area was largely occupied by buildings and facilities, resulting in the horizontal fragmentation of waterfront green spaces. Meanwhile, the riverside towering cliffs and steep revetment separated the city from river vertically.
3. The 30-meter-high fluctuation zone caused by the periodic water storage is extremely tricky. When the water level drops, large area of slope and revetment would be exposed, which seriously deteriorate the landscape appearance along the river.
Although the complex and diverse waterfront condition brought about tough problems, it also has the great potential for renewal. By improving the existing space quality, transforming the desolated area and wastelands into new green spaces and endowing them with diverse functions, integrating fractured waterfront spaces with continuous greenway through various methods, the citizens’ public life is brought to the waterfront, and the unique landscape is formed by rationally utilizing the land in the fluctuation zone where the water level dynamically changes. Eventually, a 10km ecological and social infrastructure corridor closely connects the magnificent Yangtze River with the graceful mountain city and its 280,000 citizens.
1. Integration and connectivity
In master plan stage, it is proposed to structure a slow-traffic system throughout the whole waterfront so as to integrate the urban interface and to connect the citizens with riverside. Among the waterfront connection tasks, Pengxi riverfront area makes the most tricky and typical part. The riverside is lined with cliffs and steep revetments, with the height difference between city and reservoir reaching 20m, along with connection-blocking factors scattering around, like great bridges, urban sewage pipes.
With diversified structures, two boardwalks are created to integrate these elements as a whole. The lower boardwalk is arranged along the highest water level,available for walking and cycling. While the upper boardwalk is erected above the sewage pipe. Two crisscross boardwalks dissolve the influence of negative landscape, as well as weaken the sense of distance between the city and the river. In the cliff area, the boardwalk is overhung from the rock, provides a spectacular landscape of cliff and river. Downside Shuangjiang Bridge, two natural rocks on both sides of the bridge pier are utilized to serve as structural foundation of the boardwalk, which allows the slow-traffic system to stay connected.
2. Creation of vigorous open spaces
Several existing waterfront sites are transformed into varied urban open spaces with different functions and styles.
Sunshine Beach. Located in the fluctuation zone, the site used to be a simple and dilapidated swimming pool and skating rink. With the ground being elevated, the site is transformed into an all-year-round available open space above the highest water level. A swimming pool and a paddling pool are created on the east to retain the original function, and the west part is designed into a beach, the largest one on the upper reaches of the Yangtze River, as a multifunctional urban space. Meanwhile, the previous engineering revetment is transformed into sitting terraces under the tree canopy, providing the view to the river, mountains and the bustling crowd. With fully use of the height difference, a service building is created, the roof of which is a viewing platform. Since the Sunshine Beach completion, national beach volleyball competition has been undertaken here twice.
Water Garden. It used to be an abandoned peninsula below the Yangtze River Bridge, surrounded by water on three sides and owns a great outward view, is turned into a small natural-styled garden. The water garden features spring-flowering small arbors and autumn-coloring plants. The center of the garden is an open lawn, with a series of platforms arranged along the waterfront. The space under the bridge is also fully utilized as small leisure plazas. East to the site, an existing small island above the water surface is utilized to create a viewing platform in the middle of the river, being connected to the main site with a curve boardwalk.
Moonlight Lawn. Most of the site area used to be submerged during the flood period. With large amount of abandoned soil piled up here constantly in recent years, a plot of wasteland above the water surface was formed. A leisure park with several lawns is proposed, whose open spaces match the vast river well. The park consists of a series of sparse woodland lawn, riverfront walkway, grass theatre, viewing pergola and bicycle lanes, to meet different needs of waterfront activities, as well as providing the best place to view the riverscape and the mountain-scape.
3. Dynamic Landscape. Landscape architects discovered that as the water level of the reservoir recedes in spring each year, native herbs sprout naturally in the fluctuation zone and cover the exposed soil surface. In this context, the law of nature plays a key role in shaping the distinctive landscape. Thus, the original land surface is preserved to ensure the yearly grow-wither process of plants could be retained at the maximum extent. At the same time, some native aquatic plants and hygrophytes are planted at the relatively higher elevation, to enrich the shoreline landscape and biodiversity as well. In addition, immersion-resistant material is used in the fluctuation zone to create simple trails and platforms for public activities at low water level. Benches on the platforms are designed into stone numbers to represent the different levels of each platform, make the water level fluctuation be sensible.
Conclusion. By coordinating with the departments of the Three Gorges Reservoir and other city administrations, the landscape architects struggled 7 years to transform the negative urban riverside space into a social and ecological infrastructure corridor connecting 280,000 citizens. Diverse slow-traffic system creatively integrates the previous fragmented waterfront interface; Series of gardens, plazas, green spaces, platforms, and beach serve as the city’s new stages for public activities and cultural landmarks to bring public life to the waterfront. Meanwhile, the dynamic landscape presented by the 30-meter hydro-fluctuation belt of the Three Gorges Reservoir area also integrated as part of the waterfront greenway of Yunyang, unfolding the dynamic beauty of nature.
In the project of Yunyang Riverside Green Corridor, the landscape architects encountered unprecedented challenges due to the factors of nature, society and technology. Yet the final completion of the project significantly demonstrated that the landscape architecture profession is competent in overall leadership coordinating other professions including hydrology, urban planning, municipal management, etc. This project has now become a model of urban waterfront management and environmental improvement in the Three Gorges Reservoir area in China, which makes this small county town a star city in the region all at a sudden. With the gradual connection of riverside parks and slow-traffic systems, new cultural facilities at the riverside area are also be constructed. With the ideology of concerning civic life and respecting nature, the riverside green corridor stitches the river with Yunyang, the “Migrant Town of Three Gorges” less than 30 years old. It is now not only playing a significant role in urban public life and ecology, while also continuously expanding its influence in regional culture-building, urban space organization and tourism development.