Ottelia acuminata, an aquatic plant species endemic to Southern China, is an indicator species for clean water. Its reblooming in Erhai Lake demonstrates the ecological recovery process, from a polluted body of water to a resilient and sustainable waterscape. This ecological restoration project improved the threatened ecosystem by creating opportunities for the growth of these delicate blossoms.

Erhai Lake plays a vital role in connecting residents of towns around the lake spiritually with mother nature, such as Shuanglang, Xizhou, etc. It serves as a worship place for the Bai people, an ethnic minority with a population of about 53.8% in Dali. Utilizing this unique attachment to the waterscape, the design team maximized ecological benefit with minimal human intervention. The design reinvigorates Dali City’s iconic yet filthy water and restores the landscape, environment, and habitat of endangered species while supporting the needs of nearby industry and agriculture.

This project established a 129-kilometer-long, 900-hectare open reservation area along Erhai Lake. Its water quality and biodiversity have significantly improved, providing a sustainable lake restoration strategy and system for organizations worldwide.

Complex site constraints forced the design team to propose landscape planning methods that differed by scale, making dynamic responses to social challenges with the re-evaluation of the gift of nature, so as to expand nature’s efficiency. Commencing in March 2018 and completed by 2021, this project constructed a nature-based solution for waterscape management in the scale of entire watershed with multidisciplinary cooperation, government intervention, and public participation.

After construction, the team tested the effectiveness of the ecological restoration through continuous monitoring. In the 900-hectare natural lakeside buffer zone, 350 ha wetland can reduce chemical oxygen demand by 1,160,957 kg, total nitrogen by 59,540.7kg, and total phosphorous by 17,963.7 kg annually. The water quality of Erhai Lake has been upgraded from Case IV to Case II (water standard in China). Biodiversity, especially the number of birds, has improved significantly. The Ottelia acuminata that were wiped out by pollution have returned to rebloom.

This project proposed effective methods and strategies to protect the natural landscape and resolve the conflicts between man and nature. It reflects the ability to solve complex social and economic problems, reversing the negative impacts of overdevelopment and facilitating the development of a healthier and more cohesive Erhai Lake community. The project raised the quality of life for residents and preserved the culture of minorities. The average passenger flow in the Erhai area has reached 11,600 people a day, with more than 4,000 people using bicycles and other slow-traffic facilities. The upgraded environment has positively influenced the local industry. The restored lakeside attracts many primary school classes, photographers, and hikers, making for a more colorful and engaging community atmosphere.

Erhai Lake Ecological Restoration Project sets forth methods and strategies to protect the natural landscape and solve the contradiction between man and land, permanently limits poor development practices and has outlined a regional process of responsible development combined with preservation of lake.

Other landscape architecture offices involved in the design of landscape: ZEHO ECO，BIDR

Project location: Dali City, Yunnan Province, China

Design year: February 2019 – June 2021

Year Built: June 2021