Grange Planning Brain

title: Amendment C104gpla - Teesdale Flood Study FO and LSIO Mapping council: golden-plains state: vic category: amendment classification: MAJOR status: pending last_compiled: 2026-05-30 source_docs:

  • Final Council Meeting Agenda 23.09.2025.pdf
  • Item 7.1 Attachments - Planning Scheme Amendment C104gpla - Teesdale Flood Study Panel Report.pdf
  • Council Meeting Agenda 22.04.2025.pdf
  • Item 7.1 Planning Scheme Amendment C104gpla Teesdale Flood Study 5.pdf
  • AGENDA - Council Meeting - 24 October 2023.pdf
  • 8.4.1 - Authorisation of Planning Scheme Amendment C104 - Tessdale Flood Study.pdf
  • 8.4.2 - Authorisation of Planning Scheme Amendment C104 - Tessdale Flood Study-2.pdf

Amendment C104gpla - Teesdale Flood Study FO and LSIO Mapping

Amendment C104gpla is a flood-risk mapping amendment for Teesdale that seeks to replace outdated Flood Overlay and Land Subject to Inundation Overlay mapping with controls based on the Teesdale Flood Risk Identification Study and 1% Annual Exceedance Probability flood modelling with climate change to 2100. (Source: Final Council Meeting Agenda 23.09.2025.pdf, p.6) Its practical effect is to move flood intelligence from a technical study into the Golden Plains Planning Scheme, so future subdivision, buildings and works in affected parts of Teesdale are assessed against mapped flood hazard rather than older overlay boundaries. (Source: Council Meeting Agenda 22.04.2025.pdf, pp.8-11)

Background

Council commissioned Water Technology to prepare the Teesdale Flood Risk Identification Study for Native Hut Creek and tributaries in Teesdale. (Source: AGENDA - Council Meeting - 24 October 2023.pdf, p.16) Teesdale is identified as a Priority Flood Risk Area in the Corangamite Regional Floodplain Management Strategy because the town has both riverine and flash flood risks and Native Hut Creek flooding has damaged residential properties. (Source: Council Meeting Agenda 22.04.2025.pdf, pp.6-7)

The study was funded through the Risk and Resilience Grants Program managed by Emergency Management Victoria, with Australian Government and Victorian Government funding under the National Partnership Agreement for Disaster Risk Reduction. (Source: Final Council Meeting Agenda 23.09.2025.pdf, p.6) Council adopted the study and authorised preparation and exhibition of the amendment on 24 October 2023. (Source: AGENDA - Council Meeting - 24 October 2023.pdf, p.16) The Minister for Planning authorised the amendment with changes on 14 November 2024. (Source: Council Meeting Agenda 22.04.2025.pdf, p.8)

Analysis

What the amendment changes

The amendment implements the Teesdale Flood Risk Identification Study by amending the Flood Overlay and Land Subject to Inundation Overlay maps in Teesdale. (Source: Final Council Meeting Agenda 23.09.2025.pdf, p.6) The mapping is based on land likely to be within the 1% Annual Exceedance Probability flood extent with an 18.4% projected rainfall intensity increase to 2100. (Source: Council Meeting Agenda 22.04.2025.pdf, p.8) The 2100 horizon was selected because built form such as housing is expected to remain in use over that timeframe. (Source: Council Meeting Agenda 22.04.2025.pdf, p.8)

The number of Teesdale properties affected by the FO and LSIO was reported in 2023 as increasing from 103 to 141 properties, including 28 properties with existing houses. (Source: AGENDA - Council Meeting - 24 October 2023.pdf, p.17) The amendment therefore does not operate as a township-wide growth control; it is a targeted hazard-control update affecting identified floodplain land. (Source: AGENDA - Council Meeting - 24 October 2023.pdf, pp.17-19)

The amendment also fixes a separate planning-scheme administration problem created after Amendment C80gpla introduced FO1 and LSIO1 controls for Inverleigh in September 2019. (Source: Council Meeting Agenda 22.04.2025.pdf, p.8) Council reported that an administrative error during gazettal of C80gpla removed FO and LSIO schedules that had applied to existing mapping across the shire, leaving no schedules applying to those overlays since 2019. (Source: Council Meeting Agenda 22.04.2025.pdf, p.8) C104gpla would apply Teesdale schedules to existing FO and LSIO mapping, proposed to be renamed FO2 and LSIO2. (Source: Council Meeting Agenda 22.04.2025.pdf, p.8)

The flood-risk mechanism

The planning mechanism is straightforward: flood study outputs become statutory overlay boundaries, and the overlays trigger planning assessment for buildings, works and subdivision in mapped flood-prone land. (Source: Council Meeting Agenda 22.04.2025.pdf, pp.8-11) FO controls are more restrictive for higher-risk flood areas, while LSIO controls allow some development in lower-risk floodwater areas subject to floodplain-management assessment. (Source: Council Meeting Agenda 22.04.2025.pdf, p.8)

The study used hydrology and hydraulic modelling, road and drainage infrastructure inputs, rainfall inputs and topographic information from multiple LiDAR datasets. (Source: Council Meeting Agenda 22.04.2025.pdf, p.7) The modelling was tested against the 2011, 1995 and 1973 flood events and against community-supplied historical observations. (Source: Council Meeting Agenda 22.04.2025.pdf, p.7) The 2023 authorisation report records that calibration was difficult because the study area had no stream gauges, few rain gauges within the catchment and limited accurate historical flood-level information. (Source: AGENDA - Council Meeting - 24 October 2023.pdf, p.18)

Because direct instrumental data was thin, the study relied on joint validation using anecdotal information gathered through consultation. (Source: AGENDA - Council Meeting - 24 October 2023.pdf, p.18) Council’s April 2025 report states that the Australian Rainfall and Runoff guide recognises anecdotal information as valuable for flood-model calibration. (Source: Council Meeting Agenda 22.04.2025.pdf, p.9) The important planning consequence is that the amendment rests on a model validated through multiple imperfect evidence sources rather than a long local gauge record. (Source: AGENDA - Council Meeting - 24 October 2023.pdf, p.18)

Climate change and conservative mapping

The Project Reference Group, comprising Water Technology, Council, CCMA and SES members, agreed to use the high-emissions RCP8.5 scenario to 2100 for the amendment mapping. (Source: Council Meeting Agenda 22.04.2025.pdf, p.8) Council’s stated reason was that the mapping is intended to mitigate potential future impacts and reduce risk under climate uncertainty. (Source: Council Meeting Agenda 22.04.2025.pdf, p.8) The 2023 report also records that the Reference Group preferred RCP8.5 because it provided the most protection and differed only marginally from other modelled projections. (Source: AGENDA - Council Meeting - 24 October 2023.pdf, p.19)

This matters because objectors contested the climate-change assumption, but Council reported that applying RCP8.5 rather than present-day 1% AEP conditions affected only three additional properties in total and added FO coverage to part of five additional properties. (Source: Council Meeting Agenda 22.04.2025.pdf, p.10) The practical effect is that most of the overlay expansion appears to come from updated flood modelling and hazard interpretation, not solely from the climate-change uplift. (Source: Council Meeting Agenda 22.04.2025.pdf, pp.8-10)

Subdivision and development consequences

The amendment would make flood risk a more explicit constraint on subdivision and development in affected parts of Teesdale. (Source: Council Meeting Agenda 22.04.2025.pdf, p.11) Council reported that some properties may no longer be able to be subdivided if the proposed overlays identify flood-affected land. (Source: Council Meeting Agenda 22.04.2025.pdf, p.11) Council also stated that allowing additional development in flood-affected locations would be contrary to Clause 13.03-1S of the Golden Plains Planning Scheme. (Source: Council Meeting Agenda 22.04.2025.pdf, p.11)

The downstream planning effect is not only on individual dwellings; it also affects the pattern of infill and greenfield subdivision around local drainage paths because community concerns during early consultation focused heavily on subdivision-related runoff and local drainage effects. (Source: AGENDA - Council Meeting - 24 October 2023.pdf, p.18) New buildings and works within FO or LSIO land would need CCMA consideration to ensure they do not obstruct flow paths, worsen flood behaviour or create safety and damage risks. (Source: Council Meeting Agenda 22.04.2025.pdf, p.11)

Mitigation options and why mapping became the preferred response

The study assessed three mitigation options and found none financially viable. (Source: AGENDA - Council Meeting - 24 October 2023.pdf, p.16) The April 2025 report identifies the options as raising Pantics Road, alternative culverts under Bannockburn-Shelford Road and waterway vegetation clearing. (Source: Council Meeting Agenda 22.04.2025.pdf, pp.11-12) Council reported that each option had significant financial or environmental cost with very limited benefit, so none was recommended. (Source: Council Meeting Agenda 22.04.2025.pdf, pp.11-12)

The result is a non-structural floodplain-management response: rather than building works to materially change flood behaviour, the amendment changes the planning controls so future land use and development respond to the mapped hazard. (Source: AGENDA - Council Meeting - 24 October 2023.pdf, pp.18-19) This has lower direct capital cost than major mitigation works but shifts practical consequences into permit assessment, subdivision feasibility and siting decisions. (Source: Council Meeting Agenda 22.04.2025.pdf, pp.11-12)

Exhibition, submissions and contested issues

C104gpla was exhibited from 6 February 2025 to 10 March 2025. (Source: Council Meeting Agenda 22.04.2025.pdf, p.8) Exhibition included letters to affected landowners, letters to agencies and prescribed ministers, newspaper notice, Government Gazette notice, and publication on Council and Department of Transport and Planning websites. (Source: Council Meeting Agenda 22.04.2025.pdf, pp.8-9) Council sent letters to 139 owners and occupiers of Teesdale properties within the proposed FO and LSIO changes. (Source: Final Council Meeting Agenda 23.09.2025.pdf, p.6)

Council received 18 submissions before referral to Panel, comprising three agency submissions and 15 resident submissions. (Source: Final Council Meeting Agenda 23.09.2025.pdf, p.6) The agency submissions from CCMA, DTP Transport and DEECA were supportive or requested no change. (Source: Council Meeting Agenda 22.04.2025.pdf, p.9) The 15 resident submissions objected to the amendment and were not resolved before the April 2025 Council meeting. (Source: Council Meeting Agenda 22.04.2025.pdf, pp.6-9)

The resident issues were concentrated around mapping accuracy, reliance on anecdotal data, absence of 2022 flood data as a validating event, survey questions, insurance costs, property values, mitigation alternatives, climate-change projections, new development impacts and consultation adequacy. (Source: Council Meeting Agenda 22.04.2025.pdf, p.9) These objections are important because they test whether the amendment is understood locally as a risk-management correction or experienced as a new burden on affected land. (Source: Council Meeting Agenda 22.04.2025.pdf, pp.9-11)

Panel outcome

Council referred the unresolved submissions to an independent Planning Panel at the April 2025 meeting. (Source: Final Council Meeting Agenda 23.09.2025.pdf, p.6) The Panel hearing was held on 30 June and 1 July 2025. (Source: Final Council Meeting Agenda 23.09.2025.pdf, p.6) Council engaged Water Technology to provide expert evidence, CCMA joined the Panel in support of the amendment, four residents were parties, and one resident called Mark Colegate of Arcadis to provide flooding expert evidence. (Source: Final Council Meeting Agenda 23.09.2025.pdf, pp.6-7)

The September 2025 officer report states that the Panel found the basis for the amendment clear and well supported, and found the study methodology and findings appropriate as a basis for flood-control mapping. (Source: Final Council Meeting Agenda 23.09.2025.pdf, p.7) The Panel recommended that Council adopt C104gpla as exhibited. (Source: Final Council Meeting Agenda 23.09.2025.pdf, p.7)

Current Status

The verified corpus position is that, as at the 23 September 2025 Council agenda, officers recommended that Council receive the Panel Report, adopt Amendment C104gpla as exhibited, and request Ministerial approval under section 31 of the Planning and Environment Act 1987. (Source: Final Council Meeting Agenda 23.09.2025.pdf, pp.6-7) The corpus does not include adopted minutes from that meeting, a Ministerial approval decision, or a Victorian Government Gazette notice confirming approval. (Source: Final Council Meeting Agenda 23.09.2025.pdf; Source: Item 7.1 Attachments - Planning Scheme Amendment C104gpla - Teesdale Flood Study Panel Report.pdf)

Dependencies

  • Blocks: The amendment blocks unconstrained reliance on outdated FO and LSIO mapping in Teesdale because Council reports that current mapping understates flood hazard. (Source: Council Meeting Agenda 22.04.2025.pdf, pp.6-7)
  • Blocked by: Final statutory completion is blocked by adoption and Ministerial approval because the September 2025 report recommends Council request approval from the Minister after considering the Panel Report. (Source: Final Council Meeting Agenda 23.09.2025.pdf, p.7)
  • Informed by: The amendment is informed by the Teesdale Flood Risk Identification Study, hydrology and hydraulic modelling, LiDAR data, community validation, CCMA input and SES input. (Source: Council Meeting Agenda 22.04.2025.pdf, pp.7-8)
  • Implements: The amendment implements Clause 13.03-1S floodplain-management policy by identifying land affected by a 1% AEP flood in the planning scheme. (Source: Council Meeting Agenda 22.04.2025.pdf, pp.12-14)
  • Conflicts with: The amendment conflicts with some resident expectations for subdivision, insurance exposure and property value certainty because those were recurring objection themes during exhibition. (Source: Council Meeting Agenda 22.04.2025.pdf, p.9)

The key external authority is the Corangamite Catchment Management Authority, which is the floodplain-management authority for floodplain strategies and flood advice and supported the amendment at Panel. (Source: Council Meeting Agenda 22.04.2025.pdf, pp.6-7; Source: Final Council Meeting Agenda 23.09.2025.pdf, pp.6-7) The amendment also links to Emergency Management Victoria, VicSES and CFA because the study produces flood intelligence used for warning, evacuation and emergency response planning. (Source: AGENDA - Council Meeting - 24 October 2023.pdf, pp.16, 24)

Gaps in This Analysis

The extracted text for the attachment titled Item 7.1 Attachments - Planning Scheme Amendment C104gpla - Teesdale Flood Study Panel Report.pdf contains page headers but does not expose the Panel Report body text, so this page relies on the September 2025 officer summary for Panel findings rather than direct Panel reasoning. (Source: Item 7.1 Attachments - Planning Scheme Amendment C104gpla - Teesdale Flood Study Panel Report.pdf) The extracted text for Item 7.1 Planning Scheme Amendment C104gpla Teesdale Flood Study 5.pdf also contains page shells rather than the underlying study and amendment documents, so the detailed flood maps, flood depth tables, damages assessment and property-by-property overlay changes cannot be independently analysed from that attachment. (Source: Item 7.1 Planning Scheme Amendment C104gpla Teesdale Flood Study 5.pdf)

The extracted text for 8.4.1 - Authorisation of Planning Scheme Amendment C104 - Tessdale Flood Study.pdf and 8.4.2 - Authorisation of Planning Scheme Amendment C104 - Tessdale Flood Study-2.pdf likewise contains page headers without recoverable body text, so the Water Technology summary report, data collation report, validation report, design modelling report, flood intelligence report and mitigation report are not available in analyzable form through the manifest extraction. (Source: 8.4.1 - Authorisation of Planning Scheme Amendment C104 - Tessdale Flood Study.pdf; Source: 8.4.2 - Authorisation of Planning Scheme Amendment C104 - Tessdale Flood Study-2.pdf) This is a material corpus gap because it prevents independent checking of model assumptions, flood depths, velocity outputs, damages estimates, mitigation benefit-cost results and exact land parcels affected. (Source: AGENDA - Council Meeting - 24 October 2023.pdf, pp.16-18)

A further status gap remains because the manifest does not include confirmed minutes for the 23 September 2025 meeting or a gazettal notice, so the amendment should be treated as pending Ministerial approval unless later approval evidence is added to the corpus. (Source: Final Council Meeting Agenda 23.09.2025.pdf, pp.6-7)

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