I recently had a great interview session with several officers of the construction employer. I sent a thank you to each one and am hoping for a decision soon. It has been about a week. What should be my next move? I am afraid that my chances of an offer is getting slimmer by each passing day.

There can be several reasons there has been no decision yet and you have not heard back. Foremost, they may still be interviewing other construction executive job seekers. When you left the interview did you ask them when they expected to make a final decision?
If you worked with a recruiter to get the interview I would call them and ask for a progress update; that's their job. If you didn't work with a recruiter, try sending an email to the decision maker.
In the email bring up another benefit of hiring you and mention something said in the interview that will jog their memory as to who exactly you are. There is nothing wrong with persistence. You just need to be careful in becoming annoying.