Appears to be a water main for the sprinkler system.

Huntsville Utilities has received your service request and it will be reviewed by a crew for repair or replacement. Thank you for reporting this concern to us as we enhance the customer experience. No further action is required.

Thank You,
Your Huntsville Connect Customer Service Team - Huntsville Utilities

Thank you for reporting your concern to Huntsville Utilities. Your issue has been handled and we are closing your request. If you need further assistance, please let us know. Thanks for checking in with Huntsville Connect!”