Whenever it shall appear that any electrical utility, electric cooperative or consolidated political subdivision is failing or omitting, or about to fail or omit, to do anything required of it by law or by order of the Commission or is doing, or about to do anything or permitting or about to permit anything to be done contrary to or in violation of law or of any order of the Commission, an action or proceeding shall be prosecuted in any court of competent jurisdiction in the name of the Commission or the State for the purpose of having such violation or threatened violation discontinued or prevented, either by mandamus, injunction or other appropriate relief, and in such action or proceeding, it shall be permissible to join such other persons, corporations, municipalities or consolidated political subdivisions as parties thereto as may be reasonably necessary to make the order of the court in all respects effective.