In the World Bank we often discuss how important it is to integrate solutions across sectors. In Mombasa, Kenya, we have an example of how a comprehensive sediment management approach will allow the government to lower the environmental impact of a proposed dam and save tens of millions of dollars by reducing the amount of sediment that the dam traps. When too much sediment is trapped in a dam, the lifespan of the dam is shortened considerably so reducing sediment is key for long-term success.
Water management lies behind most of the great development challenges of the 21st Century. It's obvious but we too often forget that we won't be able to achieve food security, energy security, healthy cities and productive ecosystems without greatly improving how we manage water. In the global north, the challenges of basic access to water services are less pressing than they are in the south but -- as hurricane Sandy showed New York -- the challenges of making the right quantity and quality of water available where it is most needed still loom large.
While on its path to becoming the largest city in the Americas, Sao Paulo used its natural capital - water - to generate electricity, fuel industry, and satiate its ever-growing population. Natural infrastructure was traded for the concrete form and the city’s great rivers paid a high price for industrialization.
The result? Tremendous growth (averaging 5% per annum) that stimulated rapid and unplanned migration to the city and environmental pollution. Urban sprawl generated little to no infrastructure for managing water, sanitation and wastewater, or solid waste. Clearing the land for houses caused erosion and compacted soils, and the resulting increase in runoff has made an already wet city even more prone to floods.
Pakistan’s population of nearly 181 million is growing at 2% per year; this population explosion has resulted in the country meeting the international definition of water stress—water availability in Pakistan has plummeted from about 5,000 cubic meters per capita in the early 1950s to less than 1,100 m3 per capita in 2011.
This ominous, mounting water paucity impairs the lives of Pakistan’s rural women, who bear the arduous responsibility of collecting and providing water for their households. The absence of a safe water supply at or near their homes—and the resulting need to walk up to 4 km or more to get water each day—has aggravated the burden of women’s duties in many ways, making them vulnerable in terms of both their health and personal safety.
Rural women are the worst victims of water scarcity; however, in some communities, evidence indicates that women are emerging as a “herald of change.”
All climate negotiations have been based on staying below 2°C above pre-industrial temperatures. Yet it looks increasingly unlikely that that will be possible. A new report, Turn Down the Heat: Why a 4°C Warmer World Must be Avoided, suggests that there is a 40 percent chance that we will reach 4°C by 2100 even if we stick to the agreed emission reduction commitments.
What does water look like in a 4°C world?
Put simply: it's complex. Water is a complicated system and one of the major impacts of climate change is the effect on the hydrological (water) cycle. These impacts will coincide with an unprecedented increase in demand for water because of population and economic growth.