Tapped out: how can cities secure their water future?

• Published in: Water policy Vol. 15; no. 3; pp. 335 - 363
• Main Authors: RICHTER, Brian D, ABELL, David, LOUGHRAN, Maria, MESTRE, Cristina, REARDON, Melissa, SIEGFRIED, Emma, BACHA, Emily, BRAUMAN, Kate, CALOS, Stavros, COHN, Alex, DISLA, Carlos, O'BRIEN, Sarah Friedlander, HODGES, David, KAISER, Scott
• Format: Journal Article
• Language: English
• Published: London International Water Association 01.01.2013; IWA Publishing
• Subjects: Agricultural management; Applied sciences; Basins; Buildings. Public works; Cities; Conservation; Consumption; Cost analysis; Cost effectiveness; Desalination; Distribution. Storage; Earth sciences; Earth, ocean, space; Ecological effects; Ecological monitoring; Environmental restoration; Exact sciences and technology; Exhaustion; Farmers; Fatigue; Freshwater; Groundwater; Groundwater management; Hydrology. Hydrogeology; Importation; Inland water environment; Irrigation; Partnerships; Recycling; Restoration; Rural areas; Rural communities; Seawater; Stormwater; Sustainability; Timing; Wastewater; Water conservation; Water consumption; Water desalting; Water resources; Water resources development; Water resources management; Water supply; Water supply. Pipings. Water treatment; Australia; United States; North America; America; Oceania; Water supply; Water resource management; Water conservation; Urban area; Aquifers; Dry out; Prospective; Shortage; Efficiency; Town; Inter-basin transfers; Cooperation; Watershed; Rural area; Agriculture; Aquifer depletion; Water scarcity; Urban―rural partnerships; Urban water supply; Water spring; Case study; River drying; Desalination; Trend analysis; Irrigation efficiency; Transfer; Cost analysis
• ISSN: 1366-7017; 1996-9759
• DOI: 10.2166/wp.2013.105

Cities around the world are struggling to access additional water supplies to support their continued growth because their freshwater sources are becoming exhausted. Half of all cities with populations greater than 100,000 are located in water-scarce basins, and in these basins agricultural water consumption accounts for more than 90% of all freshwater depletions. In this paper we review the water development histories of four major cities: Adelaide, Phoenix, San Antonio and San Diego. We identify a similar pattern of water development in these cities, which begins with the exhaustion of local surface and groundwater supplies, continues with importation of water from other basins, and then turns to recycling of wastewater or stormwater, or desalination of either seawater or brackish groundwater. Demand management through water conservation has mitigated, to varying degrees, the timing of water-system expansions and the extent to which cities rely on new sources of supply. This typical water development pattern in cities is undesirable from a sustainability perspective, as it is usually associated with serious ecological and social impacts as well as sub-optimal cost effectiveness. We highlight case examples and opportunities to invest in water conservation measures, particularly through urban-rural partnerships under which cities work with farmers to implement irrigation conservation measures, thereby freeing up water for ecological restoration and use by cities.