If you have not already, setting up a capital committee to review expenditures in advance of the start of the project provides some assurance that the projects have been vetted against return on investment. Lastly, developing a post-audit process enables the team to review and monitor the progress of ongoing investments.
Remember not to double-dip on the capital projects EBIDTA contribution for the upcoming year - your budgetary baselines should move in concert with these investments. All projects that straddle the budgetary year, should be rolled over into the new plan. Business planning is the road map that identifies where you are headed in advance.