Large cities, towns and even small neighborhoods do not spring up overnight. They are the result of careful planning by civil and design engineers, project managers, architects, environmental planners and surveyors. The integration of these disciplines is known as urban development. Urban development is a system of residential expansion that creates cities. Residential areas are the primary focus of urban development. Urban development occurs by expansion into unpopulated areas and/or the renovation of decaying regions.

Natural Expansion

Population growth in major cities requires expansion. Urban developers look to neighboring natural territories to build needed housing and recreational areas. Natural expansion is the creation of residential areas in undeveloped or underdeveloped regions. Natural expansion requires the destruction of the wilderness. However, urban planners must work closely with environmental protection agencies to ensure that protected wildlife and plant life are not destroyed.

Urban Renovation

In extremely populated areas natural expansion is not always possible. If a large city is surrounded by other cities, there is no place for the larger city to expand into. In this case urban planners look to renovate decaying neighborhoods, obsolete industrial districts, and other unused spaces. On a much larger scale than natural expansion, urban renovation requires the compliance of city-dwellers. City planners and urban developers carefully consider the needs of the population in renovating urban areas.

Sustainable Development

Sustainable development seeks to establish a balance between human needs and environmental preservation. Urban planners consider maintaining sustainable development in expanding and renovating urban areas. When an urban area expands into wildlife regions, much care is taken to integrate the wilderness with the developing city. Sustainable development in urban expansion focuses on curtailing the city's production of pollution, increasing the availability of recycling facilities, and focusing on the efficient usage of alternative energies.

When an urban area is renovated, urban developers enact sustainable development by integrating alternative energies into the city's power grid, removing pollution producing facilities, reusing building materials, and improving existing recycling facilities.

Difficulties

Urban development is a time consuming and expensive process. It requires joint efforts between organizations, institutions and individuals. It requires major funding by governments, corporations and individuals. The development of urban areas through renovation and expansion require major transformations of existing neighborhoods, industries, transportation systems, sewage and waste management systems, technologies and cultures.

Urban developers must find a balance not only in preserving the natural environment and the development of a large city, but also in maintaining the culture and atmosphere of the original city. For example in the aftermath of hurricane Katrina urban developers in New Orleans are considering how to build a city safe from natural disasters, but also retain the vibrancy and culture of the famous city.

Criticisms

While urban development is a necessity as global populations grow, there are many criticisms of the system. Many consider the external influences of the government and urban planner's to be detrimental to the development or renovation of urban areas. Critics of these external influences argue that the inhabitants of cities should have more influence in the renovation and development of their neighborhoods. Because urban planning is focused on future development, many argue that the field ignores current problems.