The scale and nature of urban environmental problems vary at four levels: household level, community level, city as a whole and national/global level. Urban environmental problems common to most cities in the developing world are listed as follows:
- Air pollution—more heat, noise, particulates and smog
- Heat island formation due to built-up area, roads and less trees
- Buildings create local wind tunnels, obstruct air flow and cause shading
- Since the soil is covered, organisms die due to the weight of buildings
- Pavements and roads prevent infiltration, which causes flooding
- Hard built-up surfaces prevent evaporation from the soil, and hence result in less cooling
- Crowded settlements due to rising cost of land
- Breakdown of communities and anonymity breed crime and deviancy
- Slums develop through illegal occupation of public land
- Inadequate water and sanitation facilities
- Lowered resistance to many diseases
- Many people live in unsafe locations near to industries, open drains and waste dumps
- High energy consumption
- High traffic intensity
- Nightlife/24-hour society with many recreation avenues
- Impersonal, superficial, transient human relations
- Monetization of services, trading and retail
- Fashion for identity
- Nontraditional employment in industries, ports, transport, etc., often unionized, developing sub-cultures
- Cities are responsible for 75 per cent GHG emissions.
Clean water supply, waste management, noise pollution, GHG emission, high levels of road traffic, less quality green spaces, crowded housing, etc., are some of the environmental issues that are commonly observed in a city. The measures to improve the situation are to be multi-sectoral, multi-actor, multi-system and multi-level oriented. Different cities employ different measures, incorporating a few or many aspects of this multi-pronged approach.
One approach is to use technology to solve environmental issues. With the introduction of high speed internet internet (such as a leased line) into urban centres, cities become smarter and there is less reliance on paper, and wasted natural resources. Obviously technology is not a panacea and can cause many environmental issues on its own.