简介 Project Statement
An urban wetland was created as a solution to manage storm-water runoff and tail water from water supply plant. A network of water adaptive recreational uses were introduced, including pedestrian paths and resting places, which are largely detached from the ground. Cattle were also introduced to create an agricultural husbandry that is productive while creating a low maintenance solution to make the otherwise “messy” nature into a cherished urban park that is intensively used by urban residents year round.
A northern panorama of the wetland park with new urban development in the background: The network of boardwalks and bridges detached from the ground and water edges, floats above and runs through native communities, allowing intimate connection with nature without interrupting its processes.
挑战与目标 Challenges and Objectives
Harbin is one of the major Chinese cities in northeast area of the country. The city is subject to flooding due to its location at the lower reach of the Songhuajiang River. An existing 500-year flood control wall along the riverbank cuts off a 200-hectare (494-acre) wetland from the main river. The wetland habitat was deteriorating due to the lack of water supply. Meanwhile, the rapid urban development north of the site caused severe storm-water inundation while the discharge of the contaminated storm water caused the water quality of the river to decline. In addition, tail water from a newly built water supply plant dumps 1,500 cubic meters (53,000 ft3) of contaminated wastewater into the Songhuajiang River. The sum of these development and pollution inputs created worrisome problems for the local community. At the same time, public space is fervently desired due to the dramatic increase of urban population and development.
The aerial photographs along with photos of the pre-exiting site reveal the deteriorating condition of the site due to its isolation from the main river resulting from the recent flood wall. Urban storm water runoff and tail water from a water supply plant caused pollution to harm the river. The degraded ecosystem and pollution challenged and inspired the design of the wetland park.
The initial understanding of the site was to turn the isolated wetland into a major park as well as a storm water and wastewater remediation area that would enhance native wetland habitat. But thorny issues emerged as the result of further study. The landscape architect discovered that the seasonal change of the water table is as much as 2 meters (6 feet) between dry and wet seasons, which thwarts the intention to combine public spaces with a resilient wetland landscape. In addition, such a large public space would be difficult to manage since the restored native vegetation would soon become too messy and wild to allow access and used by the people year round.
Site Map and Design Concept: A water resilient park with adaptive elevated boardwalks，pedestrian bridges and platforms, which are detached from the seasonally changing wetland edges. Designed bio-swales remediate storm water runoff.
The design objective was to fashion a water resilient wetland park, which functions as an integral ecological infrastructure that remediates storm water and waste tail water from the water plant. In the process, the waste water could rejuvenate the wetland habitat. Furthermore, the landscape architect determined that limited design interventions would best serve the project objectives and transform the wetland into an accessible public space. A final challenge was establishing a low maintenance program for the park.
Urban residents enjoy platforms built into the elevated boardwalks and bridges above the water edge. They organize the landscape and provide access to the beauty of the fragile aquatic landscape in every season.
设计方案：一个功能性湿地、弹性的公园和景观牧场 Design Strategies
A working wetland for storm water remediation: A series of bio-swales were designed for the periphery of the wetland park to catch and filter the storm water runoff from the new development of the cultural center at the south and city at the north. Each day during the raining season, up to 20,000 cubic meters (706,000 ft3) of storm water on average will drain into the wetland filtration system. The bio-swales will reduce the sediment, suspended solids and heavy metals in the storm water before it flows into the central part of the wetland. In addition, 1,500 cubic meters (53,000 ft3) of tail water from the nearby water supply plant is retained and treated in the wetland to avoid polluting the river.
A series of bio-swales and ponds are designed as buffers to remediate the storm water runoff from the development area.
漂浮的连接与水弹性公园：通过配置适应性植被，使水岸绿化能应对旱季和雨季高达2米的水位差。水位线以上的植被采用放任自然的管理，较高的地带则在配置的乡土树丛（Betula platyphylla和Fraxinus mandschurica）之间种植人工草甸。在生态洼地的修建过程中，尽可能减少工程量，将开挖和回填过程结合在一起，同时尽量避免坡地整理的土方工程，以最大限度保留原有的树木和地被。每年的水位波动使水域边缘出现泥泞、脏乱、难以靠近的地带，要想将湿地建设成为市民终年可以前往活动的公共空间，显然需要处理这个难题。设计师想出来的办法是建立离岸木栈道，使人行空间与地面和湿地边缘脱离。最终建成了6公里的栈道系统，连接13个休憩平台。此外，还利用当地透水的火山沙，在高地上铺出生态友好的人行道，与湿地上的栈道一起，形成一个连续的步行网络，穿梭于树丛和草地之间，极大丰富了游客的体验。
Floating connection and water resilient park: Adaptive vegetation was designed to accommodate the two-meter annual fluctuation of the water table. In the low land, vegetation was left to respond to the process of natural succession. On the higher land, stretches of semi-natural meadow were sewn between the planted native tree groves (Betula platyphylla and Fraxinus mandschurica). Except for the minimum cut-and-fill earthwork necessary to create bio-swales, little grading was planned so that all of the existing trees and ground cover could be preserved. The annual fluctuation of the water table creates an inaccessible muddy and messy water edge, and poses a huge challenge to making the wetland into a public space that would be accessible year round. The design solution was a network of boardwalk (and bridges) detached from the ground and wetland edge. Altogether 6 kilometers (3.7 miles) of boardwalk and bridges were built, linking 13 platforms and pavilions. In addition, an eco-friendly network of pedestrian paths (using permeable volcanic sand from this region) is built on the raised ribbons of land that penetrate the groves and meadows, providing a rich experience for visitors.
Floating Connection: The flourishing regenerated wetland attracts diverse wildlife while the floating board walks and platforms allowing visitors to have an intimate contact with nature without interrupting its processes (visitors watching birds and fishing at the background of the image).
Walking on the pedestrian bridges provides a pleasant experience that allows intimate contact with the nature. The blossoming wild lotus flowers in the summer attract thousands of visitors, which are otherwise invisible and untouchable due to their remote siting in the deep marsh.
Floating above the ground and the wetland edge, the boardwalks and bridges are minimum interventions that enframe nature, which might otherwise be viewed as messy. These cultural artifacts create a new form without disrupting the natural processes and patterns.
Thirteen platforms and pavilions are strategically located along the six kilometers of boardwalks and bridges. These resting places provide great views of the wetland park and the city.
An eco-friendly network of pedestrian paths (using the permeable volcanic lava sand from this region) is built on the high ground that penetrates the groves and meadows. They create a rich experience for visitors.
Husbandry landscape and low maintenance: Since the park is largely under the control of natural, rather than human, processes, it is likely to become overgrown with seasonal wetland vegetation and ground cover, forming a wild and messy naturalized landscape. Cattle were introduced to maintain low vegetation on the high land zone so that the landscape will be accessible and usable as a park. A second benefit is the production of food and an enriched landscape experience for the city dwellers that have long been separated from agriculture.
Native meadows were designed between the forest groves and the wetland edge. These are composed of self-seeding flowers create annual surprises when they are encountered within the enclosing densely forested uplands.
The integrated pedestrian network of walking and resting facilities are detached from natural habitats and are universally accessible, allowing people of all abilities to have intimate touch with the marshy nature.
By these landscape strategies, the former deteriorated wetland habitat and a neglected peri-urban site has been successfully transformed into a working wetland that remediates urban storm water runoff and waste tail water from the water supply plant. An adaptive water resilient park was created through the minimum intervention of a network of boardwalk and resting places, which enable people to be close to nature but without disturbing nature. Thus, the recreational use of a park for people is fulfilled, and the nature can recuperate.
Each of the thirteen resting platforms are detached of the ground to impose minimum impact on the native habitat. Each of them is uniquely designed in response to the local setting, and creates a contrasting surprise in the overgrown landscape. It is a minimum strategy to order and enframe the messy nature
Children have the opportunity to play and interact with the newly regenerated lush vegetation via the newly created park network.。
Minimalist design elements such as including tree groves, meadows and colored accesses (pave with local lava sand) effectively transformed the otherwise open and generic landscape into pleasant spaces and places accommodating various recreational activities.
委 托 方：哈尔滨松北投资发展集团有限公司
Project Location: Harbin City, Heilongjiang Province, China
Project Size: 118 hectares
Date of Design: July, 2011
Date of Completion: July 2013
Client: Songbei Investment Development Ptd Ltd, Harbin City