Assessment Standard for Sponge City Effects

In 2014, China initiated its national action plan for sponge city development aiming to tackle urban water and environmental challenges. Since then, numerous projects have been implemented across 30 pilot cities and beyond in China through two development stages. The sponge city development, based on a systematic approach of "source reduction, process control, and systematic remediation", adopts comprehensive technical measures of "infiltration, detention, retention, purification, utilization and discharge", and coordinates the different aspects of water quantity and quality, ecology and safety, centralized and decentralized, green and grey, landscape and function, on-shore and off-shore, surface and underground, etc. It aims to control urban runoff effectively, to minimize the impacts of urban development and construction activities on the natural hydrological characteristics and ecological environment, and to enable the city's resilience like a "sponge" to adapt to environmental changes and natural disasters. This assessment standard for sponge city effects published by the Ministry of Housing and Urban-Rural Development of P.R. China is an attempt to provide guidance on the assessment of the effects of sponge city development projects and the city development as a whole. The main technical contents of this standard include: 1) general provisions; 2) terms and symbols; 3) basic requirements; 4) assessment items and 5) assessment methods. The publication of the English version of the Chinese assessment standard aims to provide non-Chinese readers an insight into what objectives are to be achieved through sponge city development and how sponge city projects are evaluated in China.