The present paper showcases the main developments in the implementation of an asset management system for water and sanitation infrastructure in Mozambique using opensource solutions in all of its components: data collection using Open Data Kit (ODK), central database and WebGIS. Its main goal is to provide sound data on all the water sectors, including rural and urban components, for decision support. Low-cost implementation and no field internet access posed a challenge in accessing system data for correct monitoring of previously surveyed infrastructures, so developments were made to m-SINAS (mobile app) to complement ODK features to make possible offline monitoring. The new National Water and Sanitation Information System (SINAS) data are currently being used for planning purposes, especially in regions where data collection efforts are more advanced.