Dimension | Indicator | Sources | Observations |
Capacity, access and availability | Water available for use (EA definition) per capita - dry year | Water available for use (EA definition) and population data obtained from the June reports of regulated companies (Table 10i), available here: http://www.ofwat.gov.uk/regulating/junereturn/ | Geographical coverage: England and Wales |
| Water available for use (EA definition) per capita - critical period | Water available for use (EA definition) and population data obtained from the June reports of regulated companies (Table 10iii), http://www.ofwat.gov.uk/regulating/junereturn/ | Geographical coverage: England and Wales |
| Sewage treatment capacity | Sewage treatment capacity: data obtained from the June reports of regulated companies (Table 15), http://www.ofwat.gov.uk/regulating/junereturn/ | Geographical coverage: England and Wales |
Asset or capacity utilisation | Security of Supply Index - dry year | SOSI: data obtained from the June reports of regulated companies (Table 10i), available here: http://www.ofwat.gov.uk/regulating/junereturn/ | Geographical coverage: England and Wales Individual company scores were weighted by population Veolia South East was excluded due to data unreliability issues |
| Security of Supply Index - critical period | SOSI: data obtained from the June reports of regulated companies (Table 10iii), available here: http://www.ofwat.gov.uk/regulating/junereturn/ | Geographical coverage: England and Wales |
| Sewage treatment capacity utilization | Total load entering sewerage system: data obtained from the June reports of regulated companies (Table 15), available here: http://www.ofwat.gov.uk/regulating/junereturn/ | Geographical coverage: England and Wales Note: assumes 1 tonne of BOD is equivalent to 1 tonne of BOD5 |
Service quality and reliability | Interruptions of supply | Properties subject to unplanned supply interruptions of 12 more: indicator reported in Ofwat's "Service and delivery - performance of the water companies in England and Wales" available here: http://www.ofwat.gov.uk/publications/los/rpt_los_2009-10 | Geographical coverage: England and Wales |
| Properties subject to sewer flooding incidents | Properties subject to sewer flooding incidents (overloaded sewers and other causes): indicator reported in Ofwat's "Service and delivery - performance of the water companies in England and Wales" available here: http://www.ofwat.gov.uk/publications/los/rpt_los_2009-10 | Geographical coverage: England and Wales |
| Inadequate pressure of mains | Pressure of mains water - Percentage of connected properties below reference level: indicator reported in Ofwat's "Service and delivery - performance of the water companies in England and Wales" available here: http://www.ofwat.gov.uk/publications/los/rpt_los_2009-10 | Geographical coverage: England and Wales |
Asset condition | Distribution losses | Distribution losses: indicator reported in Ofwat's "Service and delivery - performance of the water companies in England and Wales" available here: Mains length: data obtained from the June reports of regulated companies (Table 11), available here: http://www.ofwat.gov.uk/regulating/junereturn/ | Geographical coverage: England and Wales |
| Leakage as a distributional input | Total leakage: indicator reported in Ofwat's "Service and delivery - of performance of the water companies in England and Wales" Distributional input: indicator reported in Ofwat's "Service and delivery - performance of the water companies in England and Wales" available here: http://www.ofwat.gov.uk/publications/los/rpt_los_2009-10 | Geographical coverage: England and Wales |