A/HRC/30/39 household size, income and property value, among others, with care taken that marginalized and vulnerable individuals and groups are not being charged an unaffordable rate. 2. Uniform volumetric tariff 64. Uniform tariff approaches depend on a metered system, where households pay a fixed rate for each unit that they use. Such systems will generally be cheaper to administer than a differentiated system. However, they do not take account of households’ size or ability to pay, or whether a household has particular needs that will require more water, such as dialysis or other health needs. They will almost invariably lead to better-off households having access to more water or paying lower bills than poorer residents. Where poorer households access larger quantities of water to meet their requirements, services may become unaffordable without additional safeguards. 3. Differential pricing 65. Differentiated tariffs, which intend to provide a lower tariff targeted at poorer households or communities, may be more complex to administer but may help to ensure affordability even for disadvantaged households. Yet, difficulties remain in ensuring that they actually reach the target groups. In the United States, several municipalities have adopted differential pricing with the aim of higher-income households subsidizing lowerincome households. Recently, the Philadelphia City Council passed legislation to establish a low-income programme to ensure that water bills are affordable in relation to income. To ensure that residents are aware of the programme, the bill places an affirmative obligation on the city to refer them to the programme. 66. Increasing block tariffs is a common model for differential pricing in which differing quantities of water (or sewage) are charged at different rates. The first “block” may be set at a “lifeline” tariff – a sufficient quantity for the average household – at a low rate, generally below the cost of providing the service. Once this first “block” has been used, there is an increase in price so that households using water beyond their basic domestic and personal needs will pay comparatively more. 67. To ensure affordability for all households, it is imperative that the blocks are set appropriately. If the first block is too small, or the tariff is too high, poor families will not be able to afford to buy sufficient quantities of water. However, if the first block is too large, or the tariff too low, then people who do not actually need the lowest rate will benefit, which may put the overall financial sustainability of the system at risk. 68. One problem with this system is that often poorer households have more household members or share their connection with other households, and will therefore reach the maximum quantity for the “lifeline” tariff, and be forced to pay a higher rate, as is the case in Jordan (see Special Rapporteur’s report, mission to Jordan (A/HRC/27/55/Add.2), para. 24). In Portugal, the regulator has therefore proposed that municipalities and providers ensure a particular tariff for people living in larger households,40 as has Los Angeles.41 40 Water and Waste Services Regulation Authority (Portugal) Recommendation No. 01/2009 “Tariff formation for end-users of drinking water supply, urban wastewater and municipal waste management services” (“Tariff Guidelines”), para. 1.2, available from http://www.ersar.pt/Website_en/ViewContent.aspx?SubFolderPath=%5CRoot%5CContents%5CSite EN%5CMenu_Main%5CDocumentation%5CERSAR_OtherDocuments&Section=Menu_Main&Boo kTypeID=5&FolderPath=%5CRoot%5CContents%5CSiteEN%5CMenu_Main%5CDocumentation& BookCategoryID=2&BookID=2077. 17