The French ministry of Ecology, Sustainable Development and Energy decided to launch a scientist participatory initiative in the field of water. This initiative brings the general public and scientist community together, with the aim to improve the knowledge in the field of water. The general public is invited to take pictures, film and conduct field experiments as witness of hydraulically interesting processes as propagation - deformation of surface waves in rivers as well as in oceans, river bed evolutions... The corresponding videos can refer to common or exceptional events: they will also constitute precious first hand documents. The documents produced can be commented by scientists and utilized for publishing purposes. ANSWER initiative is based on the collaborative tool WIKHYDRO, which is the wiki of the ministry of Ecology, Sustainable Development and Energy in the water field. Opened on Internet, it contains 1600 pages, 300 videos. The first feedback some months after the launch is positive and encouraging and some videos illustrating some physical phenomena have already raised the curiosity of the scientists. The follow-up of the initiative is to use the videos recorded during floods or storm surges to quantify some data as water levels or water velocities. ANSWER is a response to our connected society, which uses new technologies of information and communication technologies (ICT): Internet, smartphones, social networks, smart sensors... The citizen, who provides geo-referenced data, becomes a major actor of his territory. The qualitative and quantitative big data mining can contribute to improve public policies in the fields of prevention, forecasting and resilience of territories.