Freedom of information act. - also contact your state agency.
Most city , town and county offices want you to comply with drainage tie ins , that is what the planning part of the planning, buliding and inspection department is all about. You pay their salaries via your taxes so that when you require help with their infrastructure they are there to assist you. They should not be confrontational, after all, they are going to get revenue from you when you apply for the permit and you might as well do the installation to their code compliance.
To not give you this basic information is assinine.

You may have to change the intake pipe so that it has two sided catch basin assemblies. The NDS catalog most likely has what you need. NDSPRO.com