A global portal for advancing sustainability in WASH

Water Person Years

International development should be based on a vision that investments today should last for generations to come. With this long-term perspective, Water Person Years will be a practical way to measure impact, efficiency and sustainability.delete

In early 2011, an informal working group was formed to come up with a better unit for capturing sustainable WASH services and to collect data on alternative indicators for these services. The founding members are representatives from Fontes Foundation, Improve International, WASH Advocates, WASHCost and Water For People.

Throughout 2011 the group has organized monthly meetings and is now ready to open the discussion to other interested professionals and organizations. The working group has decided to focus on the indicator water-person-years (WPY) developed by Fontes Foundation and test whether it can be used both to measure past successes and to guide decisions about future investments.


  • Map the existing efforts in the sector to develop and try out new indicators
  • Test water-person-years in practice and further develop and improve the indicator
  • Test water-person-years for sanitation
  • Disseminate information about the WPY indicator and promote its use
  • Create a platform for discussion for professionals and information in the sector
  • Participate at conferences and events around the topic
  • Map the impact that indicators have on policy-makers, project design and investment in the sector

    Being a static indicator, coverage does not take into account the number of people that will get water every year in future from a new water system, if it is kept functional. It is therefore necessary to add a time aspect to the coverage figure when allocating funds, and this indicator is called WPY. WPY tells us how many people get access to water from year one and each year throughout the lifetime of the infrastructure, and makes it possible to express the impact of an investment in a cumulative way, over a period of time. Assessing investments in ‘water-person-years’ over a defined period of time, allows for a more efficient allocation of resources, and calls for a rethinking of the current development approach.


    The concept of ‘water-person-years’ (WPY) is a new way of measuring the impact of investments. Assessing investments in WPY over a defined period of time, allows for a more efficient allocation of resources, and calls for a rethinking of the current development approach. Measuring in WPY is necessary for shift a focus from new infrastructure development to operation and maintenance of existing water systems, something that is crucial for sustainability.

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    WPY is a tool that can be used by governments, donors and NGOs to justify long-term funding and higher budget allocations for operation and maintenance.

    Click here to apply Water Person Years to your organization's data!

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