Inspections of septic tanks by council officials will begin next year.
The Minister for the Environment says householders who own septic tanks can register with their local authority from this evening.
They have to sign up by February 1st 2013.
Inspections will be free - but it's not yet known how many will be carried out.
Phil Hogan has told an Oireacthas Committee that it will be significantly cheaper for householders to register early: