Building sustainable urban systems for the future

Planning a city to meet today's needs **without using up resources or harming the environment** for the future.

The area of **land and water** a city needs to **supply its resources and absorb its waste**.

A city designed to be **environmentally low-impact** — renewables, green space, recycling, compact form.

A city that uses **sensors, data and digital networks** to run services (traffic, energy, waste) more efficiently.

A layout where residents reach work, shops, schools and health care within a **15-minute walk or cycle**.

Grouping several street blocks and **removing through-traffic** to reclaim space for people and green areas.

Homes sit near services, so people **walk or cycle** instead of driving -> lower transport emissions.

**High consumption, wealth, car ownership and fossil-fuel energy** raise the per-person footprint (e.g. New York).

**Sustainable** = the low-footprint outcome; **smart** = the **data/technology tool** used to get there.

Barcelona (superblocks), Curitiba (bus rapid transit), Singapore (smart traffic + water), Masdar/Songdo (built eco/smart cities).

**Cost, equity, privacy and retrofitting** existing megacities — Masdar and Songdo ran over budget and under-occupied.

Both sides (gains AND limits), **named cities/schemes**, accurate terms, and a justified judgement.

A city's ability to **absorb shocks and stresses** (floods, heat, decline, rapid growth) and keep functioning and recovering.

The physical and service backbone of a city: **transport, water, sanitation, energy, waste, housing and digital networks**.

**Who decides and how** a city is run — government, business, NGOs and residents planning, funding and running the city.

Improving or extending existing systems — e.g. **retrofitting old pipes** or adding metro lines under a working city.

Designing today's infrastructure to **cope with future climate and population pressures**.

**Long-term concentrated poverty**, poor housing and weak services in parts of a city.

Land is already in use (resettlement/sprawl), ageing systems, high cost, site limits and community/planning opposition.

Rapid growth outpaces supply, so services break down — e.g. **Lagos**, where traffic, flooding and informal areas spread.

Where you build transport decides where the city expands — **Curitiba** built BRT corridors first and steered dense growth along them.

Building cities to cope with shocks: **flood defences, drainage, zoning off flood plains, green space and future-proofing**.

Strengths: flood defences and green space cut damage and cool the city. Weaknesses: high cost; rapid growth and low incomes limit it.

Both strengths AND weaknesses, a named city (Singapore, Barcelona), and a balanced, justified evaluation.