the landscaper incorrectly removing the irrigation system
I think we need clarification of what this actually means.
Eg Was it a lot only system or a common property system?
Eg what is “incorrectly”? That it was intentional but done a wrong way? Or was it unintentional?
And what exactly got removed? And what exactly was damaged by the leaks? Was it lot property(s), common property or both?
Establishing negligence is not always simple. In fact it’s often difficult. Good luck if the OC can or wants do it but it will need the OC, or its insurer, to actually establish it.