I work at an IT services company. It has about 10 departments of mostly IT consultants. Most of these departments stand on their own and there is little interaction between them.
In the past few years most of the projects we've done have been "in house" so all of the colleagues were always together for the most part of the day. In last year or two a lot has changed. A lot of people left, a lot of new people joined and, most importantly, the projects we do are now usually performed at the client's office. When we're at the client it is usually solo.
As was to be expected, most of our (new) colleagues don't feel like they are part of a team and so company morale is quite low.
I've been working on improving this and my efforts have been noticed and so I've been promoted to "community manager".
I've tried to organise knowledge sharing sessions (that we stream so that colleagues at other locations can follow as well) and after-hour drinks but I feel it is still not enough.
I've thought about organising events for two departments at a time to get to know each other but I've not had very positive feedback on that.
So my question is this: What should I do (or propose to the management to do) to get the community going again?
Edit: There is budget available to organise events but it is not easy to come by. Each department has about 100 people.
Edit2: We are allowed to take up billable time to organise events; but management feels that the commitment should come from both sides. This means that part of the time can be billable, the other part would be personal time. Such as an event in the afternoon or early evening.
We do have quite a few large meeting rooms or cantines; there is enough room to host a bunch of people. The standard infrastructure is available; projection equipment, sandwiches and beverages when needed, ...