The first problem is not Flow!
Most water suppliers will require an expensive "Back Flow Preventer" before the sprinkler system.
The 1/2" meter and the 1" line before everything is the next problem.
I suggest you go to your local irrigation supply house for assistance. You may search http://www.johndeerelandscapes.com for a supplier in you area. These people will assist you with the proper design. I don't recommend that you go to Lowes or Home Depot as they don't usually have qualified designers.