Within Teamwork Projects, you can delete a project at any stage (permissions dependent) from the Overview area within a project.
To do this, navigate to the overview area on the project you want to delete.
Click the options button (three dots) to the top right of the page, and select Delete from the Manage Project tab.
Once you delete a project it will be moved to the trash can for 30 days however this can be restored within this time frame.
For more information, see: Viewing and restoring deleted projects