The WAPC is responsible for keeping the GBRS under review and initiating changes where they are seen to be necessary. An amendment to the GBRS changes the zoning or reservation of land to allow for a different land use. The amendment process is regulated by the Planning and Development Act 2005.

An amendment is advertised inviting submissions before a final decision on a proposal is made. A submission is a chance for people to express opinion and provide information. The number of submissions received for or against a proposal will not determine the result rather it is the reasoned argument of why a particular thing should or should not be done.

Submissions assist the WAPC in reviewing planning proposals before proceeding. Advertised proposals are often modified in response to the public submission process.

Minor amendments

If a proposal does not, in the opinion of the WAPC, constitute a substantial alteration to the GBRS then it is a minor amendment. The process includes the following steps:

• The proposed amendment is referred to the Environmental Protection Authority (EPA) to decide whether environmental assessment is needed. Where the EPA requires an environmental review, this is carried out before the amendment is advertised.
• The amendment is advertised for public comment and landowners whose property is directly affected by a proposed change are contacted in writing.
• A 60 day period is provided for the WAPC to receive submissions.
• The WAPC then considers all submissions and recommends whether to modify the amendment or proceed with the original proposal. The WAPC present a report and recommendation to the Minister for consideration.
• If the Minister approves the amendment, it becomes a legally effective part of the GBRS on publication of a notice in the Government Gazette.
• Within three months of a GBRS amendment, any local government must initiate an amendment to its local planning scheme.

Major amendment

If the proposal constitutes a substantial alteration to the GBRS then it is a major amendments. The process includes the following steps:

• The proposed amendment is referred to the EPA to decide whether environmental assessment is needed. Where the EPA requires an environmental review, this is carried out before the amendment is advertised.
• The amendment is advertised for public comment and landowners whose property is directly affected by a proposed change are contacted in writing.
• A three month period is provided for the WAPC to receive submissions.
• Written submissions are considered by the WAPC. During this time, people who have made submissions may, if they wish, also make an oral presentation.
• The WAPC always reconsiders a proposed amendment in light of submissions and may choose to modify the amendment before proceeding.
• If the amendment has been substantially modified as a result of submissions, the Minister may ask the WAPC to readvertise for further public comment.
• The Minister presents the recommendations of the WAPC to the Governor for approval.
• The amendment as approved by the Governor is placed before each house of Parliament where it must remain for 12 sitting days.
• In Parliament, a member may introduce a motion to disallow the amendment. If this motion succeeds, the GBRS will not be amended. Otherwise the amendment becomes legally effective in the GBRS.