The success of Confluence is based on the principle of knowledge sharing and collaboration. However, there is another level needed to coordinate - e.g. a communication channel that lets participants organize and plan their collaboration. Integrate these channels into your intranet and your staff can coordinate with each other first and then collaborate effectively on content together.
Share information and conversations with your colleagues on a central open platform.
Build forums directly into Confluence pages and let your teams hold their discussions there. Forums can be searched for content, authors etc. or sorted according to importance.