Traditionally, urban water managers have relied on large-scale, supply-side infrastructural projects to meet increased demands for water. This supply-side approach is under increasing pressure from a variety of mega-trends. To enhance urban water security, water managers are turning toward demand-side management.
By Robert C. Brears
Traditionally, urban water managers, faced with increasing demand for water alongside varying levels of supplies, have relied on large-scale, supply-side infrastructural projects, such as dams and reservoirs, to meet increased demands for water. This supply-side approach, however, is under increasing pressure from climate change, rapid population, and economic growth and even land-use changes impacting the availability of good quality water of sufficient quantities.
To enhance urban water security, water managers are turning towards demand-side management which aims to improve the provisions of existing water supplies before new supplies are developed. There are two types of policy tools available to achieve urban water security: fiscal tools and non-fiscal tools.
Fiscal tools to achieve urban water security
Fiscal tools include water pricing and the use of subsidies and rebates to modify water users’ behavior in a predictable, cost-effective way. Urban water managers typically price water using increasing block tariff rates, which contain different prices for two or more pre-specified quantities (blocks) of water with the price increasing with each successive block, or two-part tariff systems which contain a fixed charge and variable charge. Subsidies and rebates meanwhile are used to encourage water users to make sustainable consumption choices, for instance, subsidies are commonly used to encourage the uptake of water-saving devices and water-efficient appliances or technologies while rebates are commonly used to accelerate the replacement of old water-using fixtures and appliances. Overall, positive incentives are found to be more effective than disincentives in promoting water conservation.
Cape Town hiking its water tariffs
The City of Cape Town has a block rate tariff structure for water consumption. Due to the drought, the city increased its water prices in a bid to reduce water consumption. The price for water increased by 27% from July 1, 2018, and will increase by another 30.45% in 2019 followed by a 22% rise in 2020/2021. This will result in the price of water more than doubling between July 1, 2018, and July 1, 2020. In the first round of tariff increases, the new tariffs on a monthly bill for non-indigent persons will range from R179.58 for the first 6 kilolitres of water consumed (with indigent people receiving the first 6 kilolitres free per month) to R20,365.56 for consumption over 50 kilolitres.
New York City’s On-Site Water Reuse Grant Pilot Program
New York City’s Department of Environmental Protection has launched its On-Site Water Reuse Grant Pilot Program to provide commercial, mixed-use, and multi-family residential property owners with incentives to install water reuse systems. Grants are available for water reuse systems at the individual building and district level, with district-scale projects involving two or more parcels of land such as a housing development, where the project reduces demand in the shared distribution system. Individual building-scale projects can receive up to $250,000 in reimbursement for a system designed to save at least 32,000 gallons per day (gpd), and district-scale projects are eligible to receive up to $500,000 in reimbursement for a system designed to save at least 94,000 gpd. The NYC Construction Code regulates two types of on-site water reuse systems that can be installed: wastewater reuse systems (black water, grey water, rainwater) for non-potable uses including flushing of toilets and urinals, laundry, and subsurface drip irrigation systems and rainwater reuse systems for non-potable uses including subsurface drip irrigation.
Non-fiscal tools to achieve urban water security
Urban water managers often rely on a range of non-fiscal tools to achieve urban water security including regulations as well as education and public awareness. Regulations often used include […]