Check out the California Model Water Efficient Landscape Ordinance, at http://www.owue.water.ca.gov/. It is in the process of final revision and is set to go into effect January 2010. It outlines the services and responsibilities of CIDs.
The CID process is pretty involved with classes and tests and can take awhile to get certified. If you are not quite sure you want to get the CID certification you could go for the Certified Irrigation Auditor (CIA). This you could do in a weekend with a class and a test. As a CIA you will have a general knowledge of water efficiency techniques and be able to gauge the performance of the system.
If you are an RLA already you can do anything a CID, or CIA can do. So maybe just taking some refresher/update classes on irrigation efficiency is an option.