History of piped water supply system development in Nepal dates back to 1895 A.D., when the first Bir Dhara system (1891-1893) was commissioned. The system also led to establishment of Pani Goshowara Adda and it provided limited private and community standpipes in few selected parts of Kathmandu. The water service were then gradually extended to few other prominent places like Amalekhgunj, Birgunj, Palpa and Jajarkot . The sector received a fair priority in the First Five Year Development Plan, which started in 1956, but the sector activities were placed under the Department of Irrigation for a long while until the Department of Water Supply and Sewerage (DWSS) was formally established in 1972. Since it's establishment the department has been providing lead inputs in the development of water supply and sanitation programs throughout the country. Initially DWSS was limited to constructing comparatively larger water supply systems in the district headquarters and urban centers but it gradually expanded to have a nationwide network to serve all kinds of settlements - urban, semi-urban and rural areas. Today DWSS is providing a nationwide service through its 5 regional, 42 Divisional and 28 Sub-divisional offices spread throughout the country. DWSS has strength of about 1660 staff with a fleet of more than 170 Professional who have expertise in Engineering, Chemistry, Sociology, Finance, Administration etc.
The water sector and the DWSS underwent a major restructuring in 1990 when the sector activities were streamlined by defining DWSS as the lead agency in the sector. All water supply and sanitation programs split between DWSS and Ministry of Local Development (then MPLD) were consolidated to provide one window projects delivery through DWSS. This proved a major step in sector development as demonstrated by that the existing national water supply coverage of 37% in 1990 has been expanded to over 80% as of today. Similarly, the sanitation coverage- defined as access to safe excreta disposal facility- has been expanded from about 6% in 1990 to over 50% now. After the unified program implementation approach, it has been possible to achieve worthwhile sustainability of water supply and sanitation services through active participation of benefiting community in the planning and implementation process during projects construction and by entrusting the regular operation and maintenance of these systems to the local users committees.
The interim constitution of Nepal has defined access to water as a fundamental right to its citizens and to support this, the country has set a target to provide all Nepalese with access to basic water supply and sanitation services by 2017 A D.