Dealing with Environmental Degradation Caused by Urban Sprawl Uusing Smart Code as a New Approach (Case Study: Qazvin City and its Peri Urban Area)

Over a period of 26 years, the population of Qazvin has increased by 1.6 times, while its size has become 2.9 times greater. This imbalance between population and urban area growth is called urban sprawl. Sprawl pattern causes many problems, especially in the environmental field. For example, thousand-years-old gardens in the south area of Qazvin is destroying due to urban sprawl pattern. Green belt gardens around Qazvin city purifies south industries pollution and improves air pollutant indexes Thus, finding a solution to dealing with these consequences seems to be necessary. In this study, in order to in front Qazvin sprawl pattern and environmental issues arising from it, based on the smart code instructions, a model is suggested. According to this model, the proposed strategies are listed.


Most critics agree that the major problem of general urban growth is urban sprawl. There is a broad agreement on how to tackle the current patterns and smart growth option, as anti-sprawl has been accepted. In spite of this convergence and high advertising, urban growth shift in the United States has slow speed due to traditional zoning. Smart code is proposed as an alternative for traditional zoning and solving problems related to urban sprawl. Smart code is a model which combines the special development code with urban design and land use planning. This special development code has been proposed by Duany, Plater-Zyberk and Co (2003) headed by Anders Duany. The smart code principle supports communities with urban centers, transport, Pedestrian-oriented and mixed residential complex which encourages natural and environmental protection.

According to the proposed model, regional sector codes based on smart code instructions will be prepared after determining the study area. Since these codes are flexible and the definition of each sectors may change with regard to the status quo . Regional maps can be praperad by using software such as the GIS. Subsequently, at the local level transect map can be determined according to the definitions of smart code instruction. Finally, at the smallest level the criteria for each of the blocks, streets, and buildings can be determined through the transect map.

As urban sprawl affects the region which it deals with, it must be planned beyond the city. Hence, in this study the central city region of Qazvin as a homogeneous area was chosen. Using Holdren model also proved that Qazvin has urban sprawl patterns. In this model, the sum of population Ln (proportion of the end to the beginning of the period) with gross per capita Ln equals to area Ln: Ln (402748/248591) +Ln (163.1/88.76) =Ln (6580/2206.7) 0.48+0.61=1.09 0.44+0.56=1 That is to say, 44 % of the growth is related to population growth, while 56 % of the growth is related to sprawl and horizontal growth, which suggests that Qazvin has urban sprawl patterns. In the next step, to determine the regional sectors, this study focuses on Qazvin gardens. Although in the original version of the smart code, gardens has preserved open code due to the importance of the gardens and the flexibility of smart code, a reserved open code has been proposed for this area. Qazvin gardens have an important environmental performance to deal with industries pollution which is in line with the prevailing wind direction. In this regard, smart code proposes the transfer of the development rights to protect such valuable elements. According to the surveys, considering the ecological power of land for urban and industrial development, there is a capable area in the south of Qazvin which can be used for the transfer of the development rights. Choobindar village can be an appropriate choice in this regard. After determining other sectors, regional map can be finally prepared. After determining regional sectors, regional map can be produced. This plan would be seen as an upper plan for comprehensive plans. In addition, it cleverly provides developers a tool for determining lands that must be protected or developed. In preparing regional map, some strategies has been considered, and the most important of them are listed below: Determining the areas in which development is strictly prohibited in order to protect the green and open spaces.
Controlling the physical growth of villages around the city to prevent the destruction of agricultural land.
Applying the transfer of development rights in order to protect valuable elements such as traditional Qazvin gardens.
Encouraging the creation of high density residential areas in suitable fabrics.