By 2050 it is projected that 60% of the world’s population will be living in urban areas. Coupled with rapid population growth the world will have 41 mega-cities by 2030, each with more than 10 million inhabitants. At the same time global demand for water is projected to outstrip supply by 40% in 2030 and 55% in 2050.
As such numerous cities around the world are at risk of water insecurity – the inability of a population to safeguard sustainable access to adequate supplies of good quality water – as a result of climate change and the various impacts of urbanization.
The costs of increasing water supply
Traditionally, cities facing increased demand for water, along with variable supply, have relied on large-scale, supply-side infrastructural projects such as dams and reservoirs to meet increased demand for water. This is termed ‘supply-side’ management. However, supply-side management is costly in economic, environmental and political terms. Economically, water has to be transported over long distances increasing the costs of transportation. Additionally, the water is often of inferior quality and so requires additional treatment for potable consumption, increasing energy as well as chemical costs in water treatment plants. Environmentally, large-scale diversion of water disrupts the health of waterways that support aquatic ecosystems. Politically, because the vast majority of water is transboundary, ‘importing’ water creates political tensions with other water users, irrespective of whether they are located in the same country or not.
Balancing rising demand with limited supply
To reduce demand for scarce water, cities are turning to the use of demand management strategies to make better use of existing supplies before plans are made to further increase supply, where demand management is the promoting of water conservation during times of both normal conditions and uncertainty, through changes in the practices, cultures and people’s attitudes towards water resources. In addition to the numerous environmental benefits of preserving the health of ecosystems and their habitats, demand management is cost effective as it allows cities to better allocate scarce financial resources, which would otherwise be required to build expensive dams and water transfer infrastructure.
Achieving urban water security through demand management
Urban water security – the ability of an urban population to safeguard sustainable access to adequate supplies of good quality water – can be increased through demand management that aims to: reduce loss and misuse; optimize water use by ensuring reasonable allocation between various users while taking into account downstream users, both human and natural; facilitate major financial and infrastructural savings for cities; and reduce stress on water resources by reducing unsustainable consumption levels.
Types of demand management instruments
There are two types of demand management instruments available to cities to achieve urban water security: economic and regulatory instruments and communication and information instruments. Economic and regulatory instruments include: the pricing of water to lower consumption levels; subsidies and rebates for the uptake of water-efficient technologies; retrofitting of new or existing developments with water meters and water efficient devices; and product labeling of household appliances’ water efficiency. Communication and information instruments include public education on the need to conserve water including public events and social media campaigns that raise awareness on the need to use water wisely as well as school curriculum that raises awareness of the hydrological cycle at a young age.
With rapid urbanization and climate change impacting urban water security around the world, cities can use a variety of demand management instruments to change people’s attitudes and behavior towards scarce water resources. By balancing rising demand with limited supplies, cities not only reduce their water footprint but also make significant financial savings that can be put towards more productive uses.
Robert C. Brears is the author of Urban Water Security (Wiley). He is the founder of Mitidaption, Mark and Focus, is Director on the International Board of the Indo Global Chamber of Commerce (IGCCIA), Industries and Agriculture, and a Visiting Fellow (non-resident) at the Center for Conflict Studies at MIIS, Monterey, USA.