Located in the northern section of Huahai (Sea of Flowers), Kaiping District, Tangshan City, the project covered a total area of 2.18 square kilometers. The Expo was held from June 26th to October 18th, 2021, as a tribute to the 100th anniversary of the founding of the Communist Party of China. The original site of the project was a subsidence area caused by coal mining where the geological conditions were complicated—sinkholes and vertical shafts densely covered the area. Therefore, the biggest problem was to avoid all the dangerous parts of the area while maintaining a rational layout. ZEHO ECO, as the overall planning and design company of the project, put forward the forward-looking design concept of operating before opening up, and, with advantages of on-site design, successfully finished the work of planning, structuring, landscape, operation, ecology, architecture, and exhibition in a professional and coordinated way. We finally became the participant in the construction of the fifth Expo for the scientific planning that is highly in line with the on-site conditions and the strong construction capabilities.

With the theme of “Flower Dancing in Tangshan, a Heroic City”, the Fifth (Tangshan) Gardening Exposition of Hebei is aimed to promote urban transformation and achieve high-quality development, highlighted the function of the Huahai (“Sea of Flowers”) Project, and achieved coordinated development with Nanhu Lake. It was an outstanding expo featuring ecological restoration, innovation, smart safety, and sustainable development.

“Ecological restoration”—Green concept and ecological technology to create a modern landscape garden: No arable land was occupied as the original site was an industrial wasteland in Kaiping District. The project used 2.3 million cubic meters of construction waste, non-hazardous waste piles, and integrated geotechnical technology to build mountains from soil; built a self-purifying and self-sustaining water ecosystem to form an ecologically saving sponge; constructed ecological treatment facilities to achieve 100% recycling and reuse of sewage; created a waste recycling system through the recycling and reuse of waste plants, crushing and covering of green waste, composting use of garden waste, and domestic waste sorting and collecting.

“Innovation”—An Expo that combines traditional culture with new technologies: The overall design was based on Chinese landscape paintings. Geotechnical engineering techniques experimental modeling helped to shape the layout. We innovatively integrated five traditional ancient courtyards into the public landscape construction; meanwhile, according to the geographical conditions, pavilions, terraces, and bridges were also integrated into the landscape, demonstrating the artistic conception and essence of Chinese classical gardens. Traditional Chinese wooden structure was adopted in the construction of the main buildings, and the doors, windows, thermal insulation, and interior decoration were made of new materials, so that the “ancient” buildings can also meet green standards, to promote sustainable retention and long-term use after the Expo. Three-dimensional flower carving, national quintessence made from plants and other works, vividly demonstrated the integration of progressive new garden concepts and techniques into the traditional culture and regional characteristics.

“Smart Security”—5G and big data technology to ensure health and safety: Traditional static displays were transformed into interactive experiences with the help of big data and artificial intelligence technology. Based on experience of disaster prevention and mitigation and reconstruction gained from the Great Tangshan Earthquake, in the Safety Training Center, we used the VR technology to provide a more realistic earthquake drill, allowing people to learn safety instructions in an immersive experience; in the Smart Life Center, we built a space scene made by VR, AR, holographic projection and other technologies to create an interactive experience of light and shadow, making visitors feel as if they were in the beautiful starry sky and the Milky Way; with the help of new technologies and new materials such as smart facilities, 3D printing, etc., special exhibitions such as the Health Botanical Garden, the Smart Life Garden, and the New Material Garden carried out outdoor, parent-child, and interactive science popularization of the trend of future gardens on scenic and interesting landscapes; smart service products such as smart parking reminder and seedling identifier created a brand new smart, efficient and practical garden experience.

“Sustainable development”—to solve the problems of operation after the Expo: Cultural activities such as the concentrated display of regional culture during the Expo and research and training sessions after the Expo highlighted the contemporary characteristics of garden culture, enhanced cultural confidence, and boosted the revival of art in Hebei Province; the layout for post-conference operations had been taken into consideration since the beginning of planning and design. We brought new industries into the park to improve regional functions and coordinated other industries in the Huahai area, leading the transformation and development of the city, boosting employment of residents, and realizing a better life for all.

After the project was completed, the abandoned mine was turned into a beautiful landscape. The ecological “scars” were completely healed, and the urban “cracks” were perfectly stitched—over 150 kinds of ecological plants were used to successfully restore 91.6 hectares of industrial wasteland. The Fifth (Tangshan) Gardening Exposition of Hebei provided a model of environmental rebirth and ecological restoration, as well as a grand gardening feast, and it would become a crucial hub for economic growth that promoted the conversion of Tangshan's new and old growth drivers and green and high-quality development.