Abstract: A process for de-icing roadways to which is applied a melting agent to lower the freezing point. In order to save melting agent (salt), the melt water running off the roadway is collected and re-used for de-icing purposes provided that its melting agent content is adequate. To implement the process, use is made of a device for de-icing roadways including, along the length of the roadway, components such as spray nozzles (34) to apply the melting agent and run-off channels (16) to divert the water into a drainage channel (18) connected to a collector channel in its cycle. According to the invention, the run-off channels (16) lead into at least one collector tank (20) which returns the adequately concentrated melt water to the spray nozzles (34) via a supply line (26).