Councillors are in a position to encourage the council to take enforcement action as a priority.
In case you later need to take your case to the Local Government Ombudsman, you should keep a record of any information you give to councillors and officers.
So if you want them to do something about a breach, you need to help them understand why it's such a problem.
Councillors are more likely to pay attention when many people point out a problem, so try to gather public support for your cause.
You could ask people to sign a petition or write to the local paper about the problem, asking it to publicise it.