Within Teamwork, you can delete a project from your site at any time.
Note: Only site administrators and users with permission to add projects can delete projects from your site.
Click the options button (three dots) to the right of the project name and select the Delete option from the Manage Project section of the dropdown menu.
Once you delete a project it will be moved to the trash can for 30 days. Items can be restored from the trash can within this timeframe.
For more information, see: Viewing and Restoring Deleted Projects