There are a wealth of real world examples of communities working together to collectively manage the commons without either privatisation or state regulation.
If you want to know more you should familiarise yourself with the work of Elinor Ostrom.
There is a subtle technical difference in the literature, where regulation is externally imposed and codified, while communal management is devised, enforced, and most importantly, flexibly changed by those actually involved with the appropriation and management of the resource.
If you want to know more you should familiarise yourself with the work of Elinor Ostrom.