Sponge City: Breaking Through the Traditional Concept of Stormwater Management
Release Time:
2016-09-28
Source:
Sponge City: Breaking Through the Traditional Concept of Stormwater Management
Sponge city development should take urban buildings and residential communities, urban roads, green spaces and plazas, and water systems as its key platforms. All departments and disciplines involved in urban planning, design, construction, and project management must coordinate and collaborate effectively to move beyond the traditional “drainage-first” approach to urban stormwater management. By employing a range of eco-friendly techniques—including infiltration, detention, storage, purification, reuse, and drainage—sustainable low-impact development stormwater systems can be established.
For buildings and residential communities, green roofs can be implemented to both detain rainwater and deliver energy savings, emission reductions, and mitigation of the urban heat island effect; permeable paving should be used for sidewalks and plazas; where feasible, community green spaces should be designed as “sunken” areas, allowing rainwater to infiltrate, store, and naturally purify in these low-lying vegetated zones rather than being directly discharged into the storm sewer system; furthermore, landscape water bodies within the community can serve as integrated facilities for rainwater storage, purification, and reuse.
Urban roads are among the primary sources of stormwater runoff and associated pollutants, making effective control of road runoff particularly critical. Pedestrian walkways can be paved with permeable materials, and roadside green belts can be designed as sunken features; when space for green belts is limited, stormwater from road surfaces can be diverted to adjacent public green spaces for infiltration and retention. Urban green spaces and plazas should be developed into multifunctional “rainwater-harvesting parks” that serve both stormwater storage and regulation functions. Urban water systems should be equipped with adequate capacity for stormwater storage, regulation, and discharge, while waterfront green belts should be capable of treating stormwater runoff entering the system. Furthermore, waterfront shorelines should be designed as ecological revetments to enhance the self-purification capacity of water bodies.
Maintaining and restoring the water-absorption, infiltration, and water-purification capacities of urban green spaces and water bodies is a crucial approach to building sponge cities. Therefore, while ensuring the original functions of urban roads and green spaces, it is also essential to rationally plan land-use patterns and vertical design so that low-impact development stormwater facilities are effectively integrated with the urban stormwater drainage network and the overflow stormwater runoff discharge system, thereby fully leveraging the synergistic capabilities of urban “green” infrastructure and “gray” infrastructure.
