6.3 Planning for sustainability
You could say that the purpose of urban planning is to manage land use so that it is sustainable. This means it should bring economic benefits, with social equity and without causing environmental harm. The promotion of ‘socially and environmentally sustainable human settlements development’ is part of the mission of UN-Habitat, the United Nations programme that is ‘working towards a better urban future’ (UN-Habitat, n.d. 2). They set out five principles for urban planning, shown in Box 6.1 (UN-Habitat, n.d. 1).
Box 6.1 UN-Habitat’s five principles for sustainable neighbourhood planning
The UN-Habitat approach to urban planning is based on three key features of sustainable neighbourhoods and cities, which are that they should be compact, integrated and connected. Five principles support these three features:
- Adequate space for streets and an efficient street network.
- High density of people: at least 15,000 people per km2.
- Mixed land use: housing mixed with business and other economic uses.
- Social mix: houses in different price ranges and tenures (rented, owned etc.) in any given area.
- Limited land-use specialisation: large areas should not be allocated for a single function.
In contrast with the zoning approach, these five principles emphasise the need for mixed land use developments that integrate different functions of residential, commercial and business together. Ideally, urban plans should mix housing with employment opportunities and include schools, shops and health care facilities. An adequate street network will allow access for cars, public transport and service vehicles. Plans should also consider the need for space for places of worship and for entertainment and leisure. Incorporating this diverse range of requirements for the urban environment is challenging. To be successful and sustainable, urban plans should ideally be developed with the participation of the people who will be living and working in the area. Meeting these expectations also requires significant economic resources, an effective decision-making and regulatory framework, and good governance.
We will now consider in a little more detail some aspects of sustainable urban planning that are particularly relevant to WASH, the environment and health, but are typically absent from unplanned developments. These are: housing quality; the infrastructure related to water, sanitation and solid wastes management; drainage systems; and green spaces.