Portuguese ILIs

ILIs in Portugal 2013–15

An increasing number of Portuguese Utilities have been systematically calculating validated IWA Water Balances and leakage performance indicators as part of the National initiative for water loss and energy management (iPerdas).  The 1st (2014) and 2nd (2016) editions of this training and capacity development approach have involved 24 Water Utilities and 14 other organizations including consultants and technology providers, assisting the water utilities to develop their own water-energy loss management plans, to create awareness of the need for short, medium and long-term sustainable and integrated water and energy loss management.

13 of the 24 iPerdas Utilities and 1 other Portuguese Utility, ranging in size from around 2000 to 69000 service connections, have kindly volunteered to provide their calculated and validated ILIs for 2013 and 2015, with data provision to this website co-ordinated through the Urban Water Division of LNEC (National Civil Engineering Laboratory) based in Lisbon. This data set will substantially add to Portugal’s previous validated ILI data set of 9 Utilities from iPerdas 1st Edition previously published on the website in 2014.


Leakage Performance Categories A to D for ILI, first introduced into World Bank Institute NRW Training Modules in 2005, as defined for a High-Income Country as classified by International Water Association (IWA), are shown at the left hand side of the chart. Each Leakage Performance Category (LPC) is associated with a set of recommendations for leakage management activities appropriate to that LPC (see UARL and ILI). 5 of the 14 Utilities have ILIs in the ‘Very Low’ range  (ILI less than 1.5); and 3 Utilities are in the ‘High’ range (ILI 4 or more).

The EU Reference Document ‘Good Practices on Leakage Management’ (2015)  recommends that ILIs should be accompanied with a measure of pressure, as opportunities for pressure management for further reduction of leakage may exist. Accordingly, average pressures are also shown in the chart, with suggested categories from the EU Reference Document shown at the right hand side of the chart. Most of the systems have average pressures in the Moderate range (40 to less than 50 metres).

Acknowledgements: thanks to all Portuguese Utilities which contributed to this ILI data set, and to Helena Alegre, Dália Loureiro and Aisha Mamade at LNEC for helpful liaison associated with data provision. Congratulations also to Portugal as being the first European country to contribute a separate data set to this international ILI data base.

Future Updates: Countries in Europe and elsewhere which already have sufficient good quality ILI data to justify a separate entry within Global ILIs are also invited to Contact Us

29th October 2016