Redistribution Archive


QLD, TAS & NT federal redistributions – estimates of margins

In recent months, federal redistributions have been completed for Tasmania, the Northern Territory and Queensland, with Queensland’s being finalised on January 5.

As far as I can tell, no-one else has published margin estimates for the five Tasmanian seats and the two NT seats. Antony Green has published his estimates of the Queensland margins here. You’ll see that my estimates don’t diverge by much – by 0.1% per seat on average.

I have recently been calculating my own redistribution margins as part of the process of transferring booths so that I can produce maps for the new boundaries as part of my guides. This time I decided to use a new methodology which should be more reliable and quicker.

The AEC publishes data on how many votes were cast at each polling place (and each method of special vote) from each SA1 – the smallest area used for Census data. The AEC also publishes a list of every SA1 and which electorate it has been moved into (and out of) for each redistribution.

Using these datasets, it’s possible to quickly take the results of each booth, split them up in proportion to how much of that booth’s voters have been redistributed, and calculate new totals.

This is superior to my old methodology, where I would move booths according to which seat they lie in. Unfortunately this did not take account of small shifts where no booth moved, or where a booth was right on the border. I would have to guess how much of the booth’s voters would’ve shifted. The new method uses the actual AEC data. It is also a better solution to moving special votes. I’ve traditionally taken an even proportion of all special votes, even though this includes a bunch of pre-poll booths which are distributed across a seat. In practice these pre-poll booths would likely take more voters from one area than another, so distributing their votes according to the actual homes of the voters is far superior.

As to the results of these redistributions, 12 Queensland electorates experienced no change at all. Not one of the 37 seats has changed party. The biggest change has taken place in Lyons, with the Labor margin strengthened from 2.3% to 3.8%. The second biggest effect was in Blair, where the Labor margin was cut from 8.9% to 8.1%.

The five most marginal seats in these three jurisdictions did not experience any change. There was no boundary change in Flynn, Longman, Forde or Herbert, and the minor change to Capricornia had no impact on the seat’s margin.

The full list of margins are below the fold. I look forward to using this new method to quickly calculate margins for the three remaining redistributions (Victoria, SA and ACT) when the draft boundaries are released in coming months.

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Tasmania goes to the polls – March 3

It appears that the Tasmanian premier, Will Hodgman, will today call the state election for March 3. For the first time since 2002, the Tasmanian election won’t coincide with the South Australian election, set for March 17.

Current polling suggests the Liberal majority government (holding 15 out of 25 seats) will struggle to maintain its majority (although they do still have a chance). The balance of power in a hung parliament would likely be held by the Greens, although we can’t rule out the possibility of the Jacqui Lambie Network winning a seat. As has become common in Tasmanian elections, both major parties have ruled out governing with the Greens, which could lead to a messy outcome if neither side holds a majority. Kevin Bonham discussed this prospect in a blog post yesterday.

I have published a complete guide to the Tasmanian election. Here are the links to the five seat guides:

Each guide contains a list of candidates (to be updated when nominations close), along with an electorate history, past results, breakdowns of results into sub-areas, and maps showing those results.

Tasmania’s state electorates normally follow the same boundaries as federal electorates, but it’s worth noting that the recent Tasmanian federal redistribution has not yet been implemented for state elections. So this will be the last election using an electorate named “Denison”, and the new boundaries will first be used for the next federal election and then for the Tasmanian state election in 2022. These boundaries will likely be replaced by the time of the 2026 election.

This guide has been put together thanks to the donations of the 38 patrons who have signed up via Patreon. If you appreciate this website and would like to support my upcoming coverage of these two state elections, please consider signing up and chipping in a few dollars a month.


Queensland federal redistribution finalised

Six Australian states and territories have been due for federal electorate redistributions during the current federal parliamentary term – we’ve already completed the process in Tasmania and the Northern Territory, and the process was well under way in Queensland.

It turns out that the final decision for the Queensland federal redistribution was announced on January 5. The decision appears to be exactly the same as the draft map, which I blogged about in October.

You can download the boundaries file from the maps page, and you can see how the boundaries have changed in the below map.

This redistribution was one of the most subtle in recent years. Twelve out of 30 seats experienced no change, while the other 18 mostly experienced minor changes.


QLD federal redistribution – draft released

I’ve been quite busy recently and hadn’t had time to deal with the recent draft released for the Queensland federal redistribution.

To be honest it’s the least interesting redistribution I’ve encountered in the nine years I have written for this blog. Queensland is maintaining its 30 federal electorates after a series of rapid redistributions which repeatedly increased its seat numbers. Twelve electorates were left entirely untouched, and most of the others underwent very minor changes.

Antony Green has analysed the boundaries and made estimates for the electoral boundaries. No seat flipped party, although a few have a changed margin.

You can now download my boundary map for this draft proposal.

I have also recently updated a number of other maps: the final Tasmanian federal map, the final NSW local government boundaries as of 2017, and the New Zealand electoral map updated to reflect the results of the 2017 election. You can download them all from the maps page.


Queensland election guide – redistribution summary

Queensland has recently undergone a redistribution of state electoral boundaries, the first in almost a decade. The existing boundaries were used at three elections: 2009, 2012 and 2015.

The number of seats was increased from 89 to 93. This resulted in the creation of five new electorates, with two seats merged.

The inner-city electorates of Indooroopilly and Mount Coot-tha were merged into the new seat of Maiwar. Maiwar is a marginal LNP seat, with a margin of 3%.

Five new seats were created:

  • Bancroft – Labor seat on the northern fringe of Brisbane, with an 8.3% margin.
  • Bonney – marginal LNP seat on the Gold Coast, with a 2.2% margin.
  • Jordan – safe Labor seat at the eastern edge of Ipswich, with a 13.5% margin.
  • MacAlister – Labor seat in the north-east of Logan, with a 6.4% margin.
  • Ninderry – LNP seat on the Sunshine Coast, with a 6.9% margin.

Eleven other electorates have changed their name.

Former nameNew name
Brisbane CentralMcConnel
BeaudesertScenic Rim
Mount IsaTraeger

The last Queensland state election produced a result of 44 Labor, 42 Liberal National, 2 Katter’s Australian Party and 1 independent.

Antony Green’s redistribution estimate (which I will discuss further below) produces a result of 48 Labor seats, 42 Liberal National seats, 2 Katter’s Australian Party and 1 independent. Two of those Labor seats are now held by independent MPs elected in 2015 as Labor candidates, and one of those LNP seats is now held by a One Nation MP, elected representing the LNP.

Notes on redistribution calculations

I have produced my own estimates of the impact of the redistribution on each electorate. I have produced my own estimates as part of the process of breaking each electorate into sub-areas.

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Tasmanian federal redistribution – let’s try that again

Tasmania is currently undergoing a redistribution of its federal boundaries – the second of six federal redistributions due during this parliamentary term. The boundaries will also apply to Tasmanian state lower house elections, but probably not until the 2022 state election.

The draft boundaries were released earlier this year, and they saw a few significant changes. The seat of Bass, which covers most of the Launceston area, retracted in to just cover areas surrounding the Tamar river, losing the north-eastern corner of the state. Lyons underwent changes in a number of areas.

It is standard practice for federal redistributions to go through two rounds of suggestions and comment, followed by the release of a draft map, then two more rounds of objection and comment, followed by the release of the final boundaries. This time, however, the AEC has chosen to open up another round of objections and comment, as the boundaries released today were significantly different to the first draft.

No changes were made to the boundaries of three of the five seats, but there were significant changes to the Bass/Lyons border. Bass regained the Dorset and Flinders council areas in the north-eastern corner of Tasmania, and lost the small part of the Meander Valley council area contained within the Launceston urban area. This area was contained in Bass at least since 2001.

At the other end of the state, the Hobart-area seat of Denison has been renamed Clark, after Andrew Inglis Clark: state Supreme Court justice, Attorney-General and one of the inventors of the Hare-Clark voting system. This followed a campaign to change the seat name, including from sitting MP Andrew Wilkie and his predecessor Duncan Kerr.

You can download the new boundary map here, or view the three versions of the boundary on the below map:

I’ve seen some commentary expressing frustration about the removal of the urban parts of the Meander valley from Bass, sticking them in an electorate which stretches to the edge of Hobart.

Unfortunately it isn’t possible for Bass to contain both the Meander Valley area and the Dorset/Flinders corner without pushing Bass over quota.

Based on projected 2021 enrolment figures, Bass must lie within 3.5% of the average. In real numbers, they must have between 74,289 and 79,677 projected enrolment. Bass is projected (as drawn) to have 75,653 voters.

There are three areas which have been moved between Bass and Lyons – the Meander Valley area on the south side of Launceston, the Dorset/Flinders corner of the state, and the West Tamar area which was moved from Lyons to Bass in the original draft and remains there. Each has between 5867 and 7828 voters as of 2021, and if all three were included in Bass it would be more populous than is permitted.

So the original Redistribution Committee decided to make Bass more of a Launceston-based electorate, moving the rural north-east into Lyons, and the augmented Commission has instead decided to make Bass follow local government areas, leaving part of the Launceston urban area in Lyons.

So now there is time for interested parties to argue the case. Theoretically they could also decide to completely reverse the Lyons-Bass border back to its previous boundaries, putting the West Tamar back into Lyons, but this is unlikely.

Bass second draft74,46775,653
Lyons second draft75,50878,313
Meander Valley (Bass to Lyons)6,8407,233
Dorset/Flinders (Bass to Lyons to Bass)5,8495,867
West Tamar (Lyons to Bass)7,6757,828
Minimum enrolment67,51374,289
Maximum enrolment82,51579,677

Various map updates

Following on from the recent publication of the final Queensland state electoral boundaries, I’ve updated Google Earth boundary maps for three other jurisdictions:

  • Tasmanian federal electorates – The draft boundaries were published on May 5. These boundaries will also cover Tasmanian state lower house elections, although it is unlikely to be finished in time for the 2018 state election.
  • Tasmanian upper house electorates – The final boundaries were published in May, and will first be used at the May 2018 election.
  • North Sydney ward boundaries – I had missed a change in North Sydney’s ward boundaries since the 2012 election. The council had cut its wards from four to three, which necessarily required a change in boundaries.

You can download a large number of past, current and future electoral boundaries as Google Earth maps from the maps page.


Queensland state redistribution – final boundaries released

The redistribution of Queensland’s state electoral boundaries concluded last Friday, and I’ve now finished my map of the electorates for download. You can download the map to use in Google Earth here.

I’ve also updated my calculations of the margins in each seat, which are at the end of this post. I estimate that there are 47 Labor seats, 44 LNP seats, as well as one KAP seat and one independent seat. On my first draft, I estimated 48 Labor seats and 43 LNP seats – unfortunately I appear to have made an error calculating the margin in Pumicestone, which resulted in me predicting it was a very marginal Labor seat – I now think it’s a marginal LNP seat, despite no change in boundaries. I feel confident this is the right result, although it doesn’t make much difference when the seat is as marginal as Pumicestone is.

As part of my calculations I’ve assigned every polling place to a new seat, and split up the special votes between the new seats, and this will be used as the basis for my guide to the Queensland election, due later this year.

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Queensland redistribution – first draft released

The first draft of Queensland’s new state electoral map was released this morning, after a broad outline was leaked last night.

The redistribution is the first in almost a decade, and the redistribution will see four additional seats created in the Assembly. The combination of these factors has meant that the changes are quite dramatic.

Five new seats have been created, while two inner-city seats have been merged.

At least three prominent MPs face a significantly tougher task in winning re-election. Labor minister Steven Miles and LNP frontbencher Scott Emerson represent neighbouring seats of Mount Coot-tha and Indooroopilly. The two seats have both been abolished and replaced by the seat of Maiwar – a seat with a margin of approximately 2.8% for the LNP. They now face the choice of a tough contest or looking for a safer seat elsewhere.

Shane Knuth, a member of Katter’s Australian Party, represents Dalrymple in north Queensland. That seat has been broken apart, with a majority of the seat going into the new seat of Hill – but only 60% of that seat is areas previously contained in Dalrymple.

There are eighteen seats, including Hill and Maiwar, where the incumbent MP currently represents less than 70% of their new seat’s population.

The five new seats are Bancroft, in northern Brisbane; Bonney, on the Gold Coast; Jordan, in the Ipswich area; Macalister on the Gold Coast-Logan boundary and Ninderry on the Sunshine Coast. Some would count Hill as a new seat, but I think it’s an obvious successor to Dalrymple.

Numerous seats have been renamed, with the Commission moving away from the norm where state electorates are named after localities. The Commission instead chose to name a dozen seats after distinguished Queenslanders, following the practice of the Australian Electoral Commission, who traditionally name seats after people. The range of individuals selected for this honour are more diverse than those with federal electorates named in their honour – less politicians, and a lot more women.

This map shows the old and new Queensland state boundaries – red represents the 2009-2015 boundaries, while green represents the draft boundaries released today. Below the map I’ve also posted my own estimates of the margin in each seat. I’m sure others will do more precise analysis, but I thought I should nail my colours to the mast and post my own estimates.

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Map update – South Australia and Tasmanian upper house

I’ve recently completed two new maps for download and use: the (kind of) final boundaries for the 2018 South Australian state election, and draft boundaries for the Tasmanian upper house.

South Australia’s state redistribution was overshadowed by the federal election last year. A final set of boundaries was released late last year, with some significant changes to the draft boundaries in southern Adelaide, but these boundaries are stuck pending a lawsuit by the SA Labor Party. Both the first draft and final draft can be downloaded from the maps page, and the map is embedded here.

I’ve also completed the draft boundaries for the Tasmanian Legislative Council. The Tasmanian upper house consists of fifteen single-member electorates, but its members are elected in a very odd way: only 2-3 seats are elected each year, with members serving a six year term. Boundaries are redistributed roughly once a decade, with the sitting members assigned to finish their term representing a new seat.

There have been some major changes to the boundaries along the east coast of Tasmania. The three Launceston-area seats have remained largely the same, as have the four Hobart-area seats and the two rural seats to the west of Hobart. The west coast seat of Murchison has undergone minor changes.

The east coast seat of Apsley has been chopped up, while the seat of Rumney in the south-eastern corner of the state has been pulled in closer to Hobart, losing Sorell and the Tasman peninsula. A new seat of Prosser stretches halfway up the east coast from the Tasman peninsula to Swansea, while the remainder of Apsley has been moved into a new seat of McIntyre.

The seat of Western Tiers has been chopped up, with the north-western seats of Montgomery and Mersey expanding south and the south-western seat of Derwent expanding north. The remainder of Western Tiers has joined the remainder of Apsley as McIntyre, a strangely-shaped seat curving around Launceston, stretching from Cradle Mountain to Flinders Island.

I would expect the final boundaries for the Tasmanian upper house to be determined later this year, and the new boundaries will be used for the first time in 2018.