Is there a better approach for sidenav dashboard layout with subnavigation?

I have the following scenario in terms of navigation.

It's a dashboard admin layout. Some pages have sub-navigation. The Events menu item in the left-hand menu will render the Event List Page on the main/detail area. The Event List Page allows the user to navigate into an Event Detail Page. From this point, it has a set of navigation items that belong to the event management system itself - the News, Schedule and Maps.

The problem is, I don't know how to keep navigation consistent given the deep level model. The below mockup is the draft that I have so far, but I'm trying to choose a good approach in terms of UX (I'm not the UX guy by the way, I'm the knows nothing about UX programmer guy). It looks like a pretty good ideal but like I said, I'm not the UX guy therefore I'm not sure on it.

Anyways, is it a good approach? Is there a better approach?

^{download bmml source – Wireframes created with Balsamiq Mockups}