Would you please explain to me why the highway dep...

Would you please explain to me why the highway department can come through our neighborhoods and displace snow to cover our already clear sidewalks and obstruct access to our mailbox and access to our driveways. ? You have made more work for us. I understand the rules from your department state that if we have a private company clear our streets that they cannot cover sidewalks, obstruct access to mailboxes and driveways or cover drain systems. Why is it you can break all these rules. You do a good jobs on the main roads, but subdivisions are different.