Waipa Growth Strategy 2050
April 2017 - July 2017
Waipa District Council recently reviewed their District Growth Strategy. To support this review several scenarios were developed in WISE to represent the plausible outcomes of the draft Waipa District Growth Strategy 2050.
The key questions that were of interest to Waipa DC with respect to draft Growth Strategy were:
- Would residential growth stay within the expected criteria of:
- Always having at least 3 years of residential land supply available across Cambridge/Te Awamutu area
- There are always at least three growth cell area available for residential development across Cambridge/Te Awamutu area
- To understand infrastructure demands based on how quickly proposed growth cells might develop under population projections
- How might different demands for residential land use types (particularly lifestyle residential land use - a.k.a large lot residential) affect the development behaviour in growth cells?
Scenario Outputs
The first scenario set up in WISE used the starting “Reference” and incorporated the proposed growth cells in the draft Growth Strategy into the model. This scenario was run to represent the Reference for this case study.
Under this scenario it was noticed that there was a lot more lifestyle (large lot) residential growth than there were zoned areas in the current District Plan and draft Growth Strategy (~800 ha occurs outside ‘planned’ zoned areas).
Therefore a second scenario was developed which reduced the allocation of future population growth into lifestyle residential land use so that by 2050 only the zoned areas were occupied. The difference between these two scenarios for lifestyle residential growth can be seen in Table 1.
Table 1: Lifestyle land use allocation under Reference and Reduced Lifestyle scenarios
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Hectares of Lifestyle - allocated by scenarios in Waipa District
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Scenario \ Year
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2013
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2020
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2030
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2040
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2050
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Reference
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5027
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5405
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6003
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6343
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6431
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Reduced Lifestyle - medium
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5027
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5352
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5653
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5774
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5810
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This “Reduced Lifestyle” scenario was then run for both the medium and high population growth projections. The results were used to assess the spatial patterns and rates of residential development. The development rates for medium population projection for the Te Awamutu and Cambridge areas are shown in Figures 1 and 2 respectively.
Te Awamutu Residential growth
For the scenario using the Medium population growth projection the results show:
- The existing growth opportunities in Te Awamutu township are taken up by early 2020’s (~60 ha of development) and a further ~150 ha of development occurs in the planned growth cells by late 2020’s.
- With respect to the 3 year supply threshold of land use supply for residential land, this comes under pressure in Te Awamutu from about 2021 for medium projection. This quick uptake of growth cells means that most cells fill in the Te Awamutu area (Figure 1) leaving little opportunity for further development from early 2020’s until release of more growth cells in 2035.
- The T11 and T8 cells are slightly slower to fill and this appears to be a result of displacing existing ‘lifestyle’ and ‘other agriculture’ land uses which are more resistant to replacement.
For the scenario using the High population growth projection the results show:
- The existing growth opportunities in Te Awamutu township are taken up by 2020 (~60 ha of development) and a further ~150 ha of development occurs in the planned growth cells by about 2022.
- With respect to the 3 year supply threshold of land use supply for residential land, this comes under pressure in Te Awamutu from about 2020 slightly earlier than for the medium projection.
- Also under the high population growth scenario this lack of supply is not fixed when the planned growth cells come ‘online’ in 2036 as they fill very quickly and by 2040 there is not enough land to meet the three year supply.
Figure 1: Rates of residential infill for growth cells around Te Awamutu
Cambridge Residential growth
For the scenario using the Medium population growth projection the results show:
- The existing growth opportunities in Cambridge township are mostly taken up by early 2030 (~110 ha of development) and a further ~330 ha of development occurs in the planned growth cells in the same timeframe.
- With respect to the 3 year supply threshold of land use supply for residential land, this does not come under pressure in Cambridge under the medium growth projection. This uptake of growth cells in Cambridge (Figure 2) shows a steady infill of Cambridge North with slower infill of C2&C3 and the other available cells (C1 and C7) not starting to infill until mid-late 2020’s.
- This late response is likely to be driven by the earlier infill of Te Awamutu growth cells meaning population growth in mid-late 2020’s primarily occurs in Cambridge under this scenario.
For the scenario using the High population growth projection the results show:
- The existing growth opportunities in Cambridge township are taken up by 2026 (~110 ha of development – 4 years earlier than under medium growth projection) and a further ~150 ha of development occurs in the planned growth cells by about 2028 (2 years earlier than under medium growth projection).
- With respect to the 3 year supply threshold of land use supply for residential land, this comes under pressure in Cambridge from about 2040 slightly earlier than for the medium projection.
Figure 2: Rates of residential infill for growth cells around Cambridge
Spatial Patterns of Residential development
The spatial development of future low density residential growth for Cambridge and Te Awamutu is show using “Likelihood” animation maps in Figures 3 and 4 respectively. These “Likelihood maps” provide an indication of the likelihood that this land use (low density residential) would occur at a location at a future time based on multiple runs of the WISE scenario and a statistical analysis (Monte Carlo).
Figure 3: – Animated “Likelihood map for Cambridge low density residential development (medium population projection)
Figure 4: – Animated “Likelihood map for Te Awamutu low density residential development (medium population projection)
Implications for Growth Strategy and Other Policy
The key findings from the scenario results are:
- Te Awamutu shows slightly more residential growth early on in the scenarios compared with Cambridge.
- They have equal areas of new residential development by about 2023 and by 2050 Cambridge has significantly more new development, nearly twice as much as Te Awamutu.
- The rate of infill between the two townships is a function of the “neighbourhood” influences and geophysical suitability of cells as set up in the model. Creating a different pattern of future growth to ‘balance’ or influence spatial growth would require directed implementation of the growth strategy or other actions by property developer.
- For these scenarios the future growth cells have been released for development at two timeframes, 2015 and then 2036. This does result in some restriction in development opportunities, particularly for Te Awamutu and under the high population growth projection. However these ‘modelled’ restrictions could be avoided by tracking growth demands and releasing some growth cells for development earlier and /or changing the relative ‘restrictions’ to encourage more growth earlier in some of the Cambridge growth cells.
- The scale and location of lifestyle (large lot) residential land use needs further consideration. To keep the future growth of this land use within the planned areas in the draft Growth Strategy will required much more restrictive stance on this land use type so that only ~5% of the future population growth (between 2013-2050) can go into this land use (compared with ~20-25% over the last decade). Alternatively additional areas for lifestyle residential could be considered. The location and extent of these would need to be considered by council to strike a balance between meeting community demand and maintaining the values of a rural landscape. The pressure and opportunities from lifestyle land use will also be influenced by approaches taken by neighbouring district councils.
- Applying restrictions to create a lower level of lifestyle growth results in increased demand for low density residential land, in this case resulting in 110 ha of additional low density residential development by 2050. In these scenarios the reduction in lifestyle growth was reallocated to only low density residential. The opportunities of encouraging more medium to high density residential have not been explored in these scenarios and this could provide another avenue to manage demand for future residential land in specific areas.
Further scenarios could be developed and explored to understand possible consequences of other District policies or the effects of approaches being taken by Future Proof or neighbouring Districts on the Waipa District. Some suggested additional scenario opportunities are:
- Alternative sequencing of growth cells to minimise any development restrictions or direct growth between townships.
- Assessment of the placement and zoning setup for additional lifestyle (large lot) residential growth area
