That’s a good questions. I don’t know if any website provides this type of information for automated sprinkler systems to access. In fact, I recently wrote a research grant that proposes to integrate OpenSprinkler with government policies allowing it to be auto-compliant with the local watering policies. This would require a website like you descried that provides an API for easy checking of policy updates. But I have no idea if this type of service already exists or not.