Hydrometry data rescue, a stake for the future

The knowledge of past events and long-term series is a base to understand phenomena, analyze climate change and forecast future events. To increase long term series and their accuracy, NUNIEAU software, sort of “Digitizing Table”, was developed and distributed freely since 2006 by Cerema. It is an international reference in tide gauge record, but has been improved to widespread its used for river and rainfall record. The SCHAPI (the French national service for hydrometeorology and support to flood forecasting) launched a tender to rescue the old data on rainfall and rivers available. Many improvements have been done to manage different types of rainfall charts. NUNIEAU was developed in French and is also available in English and Spanish version with collaboration of foreign institutes. Main challenge is not only to digitize old data but also assess the quality of digitized data. Protocol has been done to control the digitizing process and after to allows assessing the final quality of data.