Zao River is one of the “Eight Rivers of Chang’an” described in Chinese historical literature. After Jue River diverted, Zao River became a river without a source and the status in the “Eight Rivers” was replaced by Jue River. In that case, Zao River assumed the responsibility of sewage and flood discharge in the southern, western and northern suburbs of Xi’an. The long-term discharge of industrial wastewater and domestic sewage has gradually deteriorated the water quality of Zao River, and the river ecosystem has also been greatly damaged. At the same time, with the development and construction of the city, the urban area of Zao River is gradually covered by urban roads, road green belts, buildings, etc., becoming an underground river. The river is heavily silted, and the pollution is prominent.
In November 2018, the Central Ecological and Environmental Protection Supervision Group pointed out that the black-odorous water of Zao River has been covered up and the construction of the sewage removal pipeline in Chang’an section has been perfunctory response. In March 2019, the Implementation Plan of Zao River Three-Year Special Regulation Plan (2018-2020) was officially issued, which aims to carry out systematic and comprehensive improvement of Zao River.
Site and Challenges: How do cities and rivers blend together
According to the existing problems and site characteristics, the Chang’an section of Zao River is divided into three parts. The upstream section is close to the source, and the surrounding areas are mostly villages and towns. The current situation of the river is a dry hard drainage canal, with disorderly growth of vegetation on both sides and a single landscape. The urban section is in the old urban district where the river has been encroached upon by urban construction, the road is narrow and there is no space for public activities. In the downstream section, the pollution of the water is severe due to sewage discharge, which has affected the surrounding residents. The negative treatment method can no longer hide the seriousness of the problem. How should this ancient river that has witnessed the dynasty change of Xi’an adapt to the development of a modern city and reintegrate into people’s lives?
▲改造前后环境对比，contrast of the environment before and after renovation
Objectives and Design Strategies: From urban sewage river to ecological landscape river, building a comprehensive urban blue-green infrastructure
This plan will make overall plans for the river corridor system, greenway system and plant habitat system, balance the layout of parks and green spaces. Expand green space and build urban ecological corridors and ecological experience areas through revetment renovation, urban greening and other measures, forming the urban green ecological network. Create a CEAD (Central Ecological Active District) that integrates ecological conservation, cultural heritage, closeness to nature, strolling and leisure, and create a new landmark for the future development of Chang’an District.
▲改造后的空间概览，不仅是一条河流廊道，更是连接城市中人与人的纽带，让人们在此休憩交谈、休闲健身、家庭交流，在这里重建社区温度 Overall view of the space after renovation. It is not only a river corridor, but also a link between people in the city. Allowing people to have a rest and talk, enjoy leisure and fitness, communicate with family, and rebuild the community temperature here.
The surrounding land of the downstream section is mostly residential communities and schools. The main renovation measures for this section are to remove the cover plate, dismantle the original revetment of masonry, widen the river channel and transform it into a variety of ecological duplex sections. Combined with the design of multi-layer steps, water playing squares and stages, make it being a dynamic area where citizens can participate and interact.
▲下游段改造前后示意图，Diagram before and after renovation
▲护岸采用流畅的曲线台阶消化高差，让原本僵硬笔直的岸线变得富有韵律感，Revetment with smooth curves
▲自然草坡亲水空间，natural grass slope space near the river
In order to meet the needs of parent-child activities, the planning and design of the 100-meter green belt, water area, and children playground provide the surrounding communities with outdoor family leisure and interactive communication spaces, which also provide an urban public space with broad vision, beautiful landscape and complete facilities.
▲户外家庭休闲娱乐的公共空间，outdoor public space for family leisure
The comprehensive river regulation of Zao River Chang’an section is a systematic solution that put forward by multi-professional collaboration and cooperation. It is to build a multi-level blue-green infrastructure serving urban citizens through the reconstruction of the river corridor ecosystem. Through the overall planning of landscape design, this project integrates the reuse of rain and flood resources, ecological flood control technology, water ecological restoration technology, etc., and builds the Zao River Chang’an section into a demonstration area integrating ecological management, science education, leisure and tourism, which will improve the regional human settlements and help the development of Chang’an District.
▲夜幕降临也丝毫没有降低儿童活动区的人气，The nightfall did not reduce The popularity of the children’s playground
▲通过丰富的夜景亮化设计，突出流畅的河岸线，为市民夜间休闲活动提供多样的公共空间 Through the night scene lighting, the smooth riverbank line is highlighted. It can also provide a variety of public space for citizens’ leisure activities at night
▲舒适的滨河空间，the comfortable riverside space
▲夜幕下的河流成为市民傍晚休闲健身的好去处，the riverside becoming the destination for local people to work out in the dusk