THE Elections Department said yesterday that the change to the boundaries of polling districts is a routine exercise that takes place when voter registers are also updated.

In an e-mailed reply to queries, the department explained how the procedure for revising the voter registers works and the knock-on effect it has on the polling districts.

The law requires that voter registers be revised within three years of the last general election - which was in May 2006.

As there would be voters who have changed addresses since then, the department looks at the addresses of voters as of Feb 1 this year, based on what is on their identity cards.

It then assigns voters to the various polling districts.

But because the number of voters in each polling district changes as a result of this, the boundaries have to be adjusted.

This is so that no polling station handles too many or too few voters.

The revised polling registers are then opened for 14 days, for eligible voters to check the department's records. If there are any discrepancies, they can raise it with the department.

After this is done, the registers will be certified and the number of voters in each polling district will be accordingly updated.

In its reply, the department said that more details of the revision exercise will be released on March 2.