Sustainable development of Zhengdong New District

1 Introduction

Plan strategy

Zhengdong New District is to the east side of capital city of Henan province---Zhengzhou, which started from Zhengzhou airport and national economic-Technological development area. It is from 107 national highway to the west, Peking-Zhuhai highway to the east, airport highway to the south, and Lian-huo highway to north, including 150 KM2 land, which equals to the current city constructed area of zhengzhou( 132 KM2 with 2.6 million residents). The plan was made in 2001 and it is said that it will be finished in 20-30 years. Now the construction of 30 high-rise apartment buildings in inner ring of the CBD has been completed. (Fig.1)

Fig.1 The constructed part

Fig.2 The spatial relationship between Zhengzhou(city on the left) and Kaifeng(city on the right)

The selection of the site is based on the region development strategy. As the capital city of the province, Zhengzhou's leading role is not enough and as a famous historical city in china, Kaifeng's(a city to the

east of Zhengzhou) has great potential. The Zhengzhou-Kaifeng region will benefit from Zhengdong new district because it located on the development axis of Zhengzhou towards Kaifeng. ( Fig.3)

Fig.3 The development strategy for Zhengzhou-Kaifeng region

In 2001, the government held the international competition for the new district plan. The Japanese architect Kisho Kurokawa won the first prize, most of his idea is realized in the final construction. He proposed to develop a southwest---northeast axis of the history and ecology for the city, with all the important land marks and points close to it, like central square, Shang dynasty relics, central government of Henan province, CBD, subcenter of CBD, Dragon lake, and the 2 main rivers going through the city:Jinshui river and Xionger river. ( Fig.4)

And according to the current X city structure by 2 railways, he planed a double V industry area.

Fig.4 Consideration of whole city

The plan of Kisho Kurokawa

Kisho Kurokawa is kind of famous in architect field and he has some ideas about city development. One of them is metabolism (metabolize and recycle)and he used it in his plan for Zhengdong new district. The main idea is to design the function areas as cells. This ideal and theoretical pattern got few chance to be realized except in competition of developing countries. (Fig.5)

Fig.5 Cells pattern Fig.6 Master plan

In the master plan ( Fig.6),the concept is to develop the area in communities, including CBD area, Dragon lake area, commercial and residential area and economic-Technological area etc. Every community is surrounded and connected by curved roads. Large green is created along rivers, lakes, highways to provide ecological environment.

In CBD area, there are 2 parts. The south ring is CBD, which is also the core of the whole new district (3.45 KM2), with two circles of 60 skyscrapers. Inner ones are 80 meters, outer ones are 120 meters high, and the pedestrian street is in between. The north circle is the subcenter of CBD, mainly office buildings, hotels and residential communities. It is also high rise, 100 meters high in the plan. The two circles is connected with a 3.7 KM canal with 40 meters buildings on both sides, forming a Ruyi shape ( Fig.7). In two rings and area to its east, more than 6 KM2 of water surface is designed, aiming to create a water town. And about the water source in this dry land of china, the master said because the area was full of lakes and ponds, the underground water level is high, and reclaimed water

Fig.7 Ruyi

could be another source. 2 Problem

Land waste

The area of the new district is the same as the old city. The problem of low quality urbanization is obvious here. And as the main agriculture area in China, the reduce of production land give more pressure to the food problem.

Function

Zhengzhou doesn't need a CBD yet because it is not in that development stage. Henan province is still in the early industry period, there is not requirement for CBD. The CBD circle is full of residential housing, because few could buy or rent the office or commercial buildings. And the occupancy rate of housing is only 15%, which make district a ghost city at night. (Fig.8) Fig.8 Residential housing in CBD

Ideal pattern and Transportation

A concept plan is taken as a construction plan and then is realized. Except the blind worship for foreigner designers, the legal process of planning and consulting in china should be considered carefully.

Then transportation problems emerge. Because of the shape of cells, the continuous curved road make driving very difficult and dangerous. And because of the independence of separate communities connected only by highways, they are like isolated islands far from old city and far from each other. While CBD requires high accessibility, if the CBD could really grow.

Landscape and water

Zhengzhou is a city in north part of china which is relatively dry comparing to south part. Its annual precipitation is 640mm, and evaporation is 1800-2000mm. Thanks to it is close to Yellow river, from which 80% water use of city come, and other 20% is from underground water. Now the crisis for yellow river is rising because of development of all cities close to it, so there is few water for landscape. As for the underground water, in old city the level has decreased for 30 meters in 30 years. So the master's plan for water Fig.9 Flyovers

source has to find alternative choice.

It is difficult to find the information of former landscape pattern,like geography and water. But it is obviously that the new plan did not take it into consideration.

Scale

The scale of new district is huge, and it is mainly for cars. The transport for people and cars is mixed, people can get lost in enormous flyovers. (Fig.9)

3 Vision from landscape perspective

Problems and solutions

Condensed development & Urban farm ( land bank )Focus to develop constructed part, return the undeveloped land to agriculture and use the land between the roads as urban farm. The north ring of subecenter of CBD can be canceled.

Mix use & development orderAs there is not enough business and many residence housing in the CBD, the strategy need to be changed into attract more people to live here in the process of urbanization. After decades,when there is needs, CBD could be developed. But in this process, as residence and cultural buildings

Fig.10 Human scale

Land waste

sizeFunctionNot enough business

Ideal pattern

Curved transport

No connections

No water for landscape

Non-human scale

Urban farm & land bankCondensed development

Mix use Change development order,residence first

Change plan for new parts

Ecological axis Track transport

Lake as wetland Reclaimed water Urban farm

Use landscape to restructure space, weak the circle

Use landscape to restructure space

already take the circle space, real CBD could be only part of the circle or outer part. So the feeling of big CBD circle could be altered by landscape, the space will be restructured. At the same time, be human scale.(Fig.10)

New Transportation planAs there is only part of the road system finished and it is difficult to change, we can only avoid the mistake in latter part.

Wetland and reclaimed water systemAlter the big lake into a wetland system with water cleaning function. Take water from reclaimed city water and clean it in the wetland. Then the central area become a part of ecological axis of whole city. (Fig.11)

Fig.11 nature reserve in city

Fig.12 Landscape connection with old city Fig.13 landscape change inside CBD