RIVER BASIN REPORT PORTLAND BASIN 13 November 2000

Flood Data Transfer Project

Department of Natural Resources and Environment

This project has been supported Prepared by: by the

390 St.Kilda Rd. Natural Heritage 3004 Ph: (03) 9272-6666 Trust Fax: (03) 9272-6611 DEPARTMENT OF NATURAL RESOURCES AND ENVIRONMENT River Basin Report - Portland Basin

DISTRIBUTION RECORD

Copy Company/Position Name No.

1 Department of Natural Resources and Environment Ian Gauntlett 2 Project File VV8159.001 3Library

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REVISION LIST

Revision Revision Description of Approved Date Number Date Revision By Revision Effected

A 21/6/2000 Issued for Client Comments D B Sheehan 21/6/2000 0 13/11/00 Issued for General Distribution D B Sheehan 13/11/00

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DEPARTMENT OF NATURAL RESOURCES AND ENVIRONMENT RIVER BASIN REPORT - PORTLAND BASIN

TABLE OF CONTENTS

PAGE NO.

1 INTRODUCTION 1

1.1 Objectives, Scope of Works and Deliverables 1

1.2 Areas of Responsibility 2

1.3 Report Contents 4

2 FLOODING CHARACTERISTICS 5

2.1 Available Information 5

2.2 Drainage Characteristics 5

2.3 Extent and Characteristics of Flooding 7

2.4 Impact of Levees and Structures 8

3 CATALOGUING AND MAPPING METHODOLOGY 9

3.1 Overview 9

3.2 GIS Content 9

4 INTERPRETIVE MAPPING 11

4.1 Coverage 11

4.2 Scope and Objectives of the Interpretive Mapping 11

4.3 Information Used 12

4.4 Criteria for Delineation of Floodways and 1% AEP Flood Extents 13

4.5 Basis of Floodway and 1% AEP Flood Extent Delineation 16

5 MAPPING OUTPUT 20

5.1 Hard Copy Mapping 20

5.2 Digital Mapping 21

6 ASSESSMENT OF DATA AND CONCLUSIONS 26

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6.1 Assessment of Data and Interpreted Extents 26

6.2 Conclusions 27

7 BIBLIOGRAPHY 29

APPENDIX A MAPPING METHODOLOGY APPENDIX B LIST OF CONTACTS MADE

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1 INTRODUCTION

1.1 Objectives, Scope of Works and Deliverables

The objectives of the digital data transfer project as stated in the Project Brief were: • To produce and deliver high quality, consistent and comprehensive GIS layer and hardcopy map products showing a range of flood data for urban and rural flood plains in . • To deliver, in hardcopy and digital form, a series of flood information reports based on Municipal and river basin boundaries. • As part of the above, to reorganise the storage of existing flood and related information within FPM (Floodplain Management Group of NRE).

There are four major elements of the project: a) Collection and transfer of NRE and other authorities flood information - a data review and management process. b) Recording and analysing the flood information in a Geographical Information System (GIS). c) Reorganisation of the source flood data under a new cataloguing system for re- storing at NRE. d) Preparation of reports and mapping to record a), b) and c).

A key output of the flood data transfer project is the formulation of Flood Data Maps which detail all captured data and Flood Planning Maps which provide 1% AEP1 Flood Extent and Floodway delineation. Both the 1% AEP Flood Extent and Floodway mapping are critical input to the flood management and land use control processes being developed by the CMA’s and Local Government.

Dialogue with municipalities was a key element of the project. This included soliciting information from them and seeking advice regarding towns to be mapped in detail and the accuracy and presentation of reports and mapping.

The Floodway and 1% AEP Flood Extent mapping has only been carried out for locations where information was available and of sufficient quality to justify delineation. Hence, the extent of Floodway and 1% AEP Flood Extent mapping is not a comprehensive coverage of all flood plains or all flooding problem areas. The Flood Data maps provide a record of available past mapping and as such known problem areas.

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The project requires delivery of three levels of reporting, namely:

• Flood Mapping Reports - are, as stated in the Brief, to provide an easy to use reference source for flood information at the municipal scale in support of planning and other related activities; • River Basin Reports - are, as stated in the Brief, to provide an easy to use reference source for flood information at the river basin scale. The river basin reports will be a major source document on flooding for CMA’s in the delivery of floodplain management services. • A Glenelg Hopkins Catchment Management Report - an aggregate report covering those parts of the three river basin reports within the Glenelg Hopkins CMA operating area.

Digital maps in GIS format facilitate access to flood information that can be readily, reviewed, analysed and amended.

This Basin Report is for the Portland Basin.

1.2 Areas of Responsibility

The area covered by this report is the Portland Basin as shown in Figure 1.1, Locality Plan. Figure 1.1 highlights the following: • Glenelg Hopkins Catchment Management Authority has jurisdiction over the Eumeralla, Moyne and systems. • part of the Shires of Glenelg, Moyne and Southern within the Portland Basin. The particular areas of responsibility are summarised in Table 1.1.

The river systems covered are all of the Eumeralla, Moyne and Fitzroy River systems, and part of the original which was diverted through the Merri River Cutting to Lady Bay in .

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% HAMILTONHAMILTON SHIRESHIRE OFOF SOUTHERNSOUTHERN GRAMPIANSGRAMPIANS

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Figure 1.1 – Portland Basin Locality Plan

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Table 1.1 - Portland Basin Responsibilities

Municipality Extent of Responsibility for River and Creeks

- Fitzroy River and tributaries Glenelg - Wattle Hill Creek and tributaries - and tributaries - Upper reaches of the tributaries of the Southern Grampians - Upper reaches of the Fitzroy River tributaries (Darlot Creek, etc) - Eumeralla River and tributaries including the - Part of the original Merri River which was diverted through Moyne the Merri River Cutting to Lady Bay in Warrnambool. - and Tributaries

1.3 Report Contents

The following sections of the report cover: Section 2. Flooding Characteristics - based on available information about flooding mechanisms and the effect of works on flooding. Section 3. Mapping Methodology - the data collection and assessment and flood mapping and GIS recording processes are outlined. Section 4. Interpretive Mapping - the basis of floodway and land subject to inundation delineation is presented. Section 5. Mapping Output - a summary of mapping output is presented. Section 6. Assessment and Recommendations - a brief summary of the quality of the mapping is provided and recommendations for extension and improvement of the data coverage.

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2 FLOODING CHARACTERISTICS

2.1 Available Information

The available information on flooding is in the following categories: • interpretive mapping of 1946 floods on part of the Moyne River in . This mapping was undertaken by the State Rivers and Water Supply Commission using historical flood levels and natural surface contours. • Non-flood aerial photography. • Hydraulic modelling to produce 1% AEP flood long-sections along the Moyne River downstream of Griffith Street Bridge. This work was undertaken by the Rural Water Commission. • A number of reports which have varying degrees of relevance to this project are: − Portland Floodplain Management Study, Rural Water Commission of Victoria and City of Portland, 1988 – this investigation determined 1% AEP flood levels for Fawthrop Lagoon and the extent of flooding along Finn Street Creek and Wattle Hill Creek. It also recommended appropriate strategies for existing and future development of the area.

2.2 Drainage Characteristics

The Portland Basin as shown on Figure 2.1 consists of several separate river systems generally flowing in a southerly direction for up to 50km before reaching the coast. Within the basin the major river systems include the Eumeralla, Fitzroy and Moyne River Systems.

2.2.1 Eumeralla River

The Eumeralla River rises in the Southern Grampians in the vicinity of Penshurst and flows approximately south west to Codrington. At Codrington the Eumeralla has a catchment area of approximately 500km2. From Codrington the River flows south east to the confluence with the Shaw River at Lake .

Little flood information is available for the Eumeralla River system.

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% HAMILTONHAMILTON

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Portland L E G E N D River Basin Boundaries

Watercourses Basin Study Area Boundary

Figure 2.1 Portland Basin River Systems

2.2.2 Fitzroy River

From its beginnings in the Lower Glenelg National Park, the Fitzroy River flows south east through Heywood and on towards the coast. By Heywood the catchment area is approximately 233 km2. Several tributary streams join the Fitzroy River including Sunday Creek immediately downstream of Heywood and Darlot Creek about 10km from the coast between Narrawong East and .

A detailed River Survey was undertaken in the early 1930s, since this time little additional investigation has been undertaken. The 1946 flood resulted in several properties being flooded in Heywood.

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2.2.3 Moyne River

The Moyne River rises in the Southern Grampians in the vicinity of Penshurst and flows south to the confluence with Backs Creek just downstream of Riddell’s Road near Kirkstall. The river continues to flow south to the only river gauge on the system at Toolong, where the catchment area is approximately 570km2. From Toolong the river flows south to Port Fairy.

Little flood information is available for the upper reaches of the Moyne River system, however due to serious flooding of Port Fairy in 1946 there are a number of sources of information within the township including a limited flood study.

2.3 Extent and Characteristics of Flooding

2.3.1 Eumeralla River

There is no recorded information on which to base a detailed description of the extent and characteristics of flooding within the Eumeralla River System. There is some interpreted flood extent information within the township of Macarthur.

The extent of 1% AEP flooding identified within Macarthur covers an approximate length of 2kms and an area of 0.6km2.

2.3.2 Fitzroy River

The extent of flooding along the Fitzroy River was defined through Heywood and downstream. The primary source for the extent along the Fitzroy River is the 1933 River Survey although this was supplemented with a field visit and observation of dryland aerial photos in the vicinity of Heywood. At Heywood the Fitzroy River breaks out into the northern flood plain and most flooding occurs north of the township. Within Heywood flooding is generally constrained to a narrow band fronting the river.

The conveyance of the Fitzroy River has been improved at various stages with some success by both private and government funded desnagging operations.

2.3.3 Moyne River

Apart from some historic and statistical data within the township of Port Fairy, there is little recorded information on which to base a detailed description of the extent and characteristics of flooding within the Moyne River System.

The conclusions that can be drawn from the available data are as follows:

• The largest flood event on record within the basin was March 1946, hence this event has been commonly adopted as the 1% AEP Flood.

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• The extent of 1% AEP flooding identified within the Moyne River System is principally confined to Port Fairy and Belfast Lough, and covers an approximate length of 22kms and an area of 11.5km2.

The Moyne River system floodplain is relatively confined to a width of generally 0.2 to 1.0 km, but with several locations where the floodplain is wider and incorporates Belfast Lough and wetlands.

2.4 Impact of Levees and Structures

2.4.1 Fitzroy River

Some levees exist along the lower reaches of the Fitzroy River downstream of Narawong East and along Darlot Creek, very little information is known about the majority of them. Significant road and rail bridges cross the Fitzroy River, following the 1946 flood some of these structures were blamed for flooding within Heywood. It is understood that the major constrictions have subsequently been removed.

2.4.2 Moyne River

There is only one significant levee for which data was available. This levee has been created by raising the level of Regent Street in Port Fairy (to act as a levee preventing flooding south of Regent Street). No as constructed survey is available to confirm that the design level of 3.2m AHD plus 300mm minimum freeboard was achieved. As a result, the levee was ignored when determining the 1% AEP flood extent.

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3 CATALOGUING AND MAPPING METHODOLOGY

3.1 Overview

An overview of the process adopted for dealing with flood mapping and other information, the GIS mapping steps and preparation and presentation of mapping and reports is presented in Appendix A. The process schematic considers both the document management processes and the major mapping stages (data collection, data capture and interpretation) of the project. The key stages of the process were: • Data collection and assessment for suitability including data management processes adopted for registering and retaining maps, plans and reports. The document register covers the DNRE FLOODATA database, existing information held by Egis Consulting and that collected from municipalities and other authorities. • GIS recording including all the data capture steps for historic floods including scanning and georeferencing, digitising and attributing, checking attributes and linework. Attributing and other GIS functions were according to DNRE Metadata requirements. Quality tolerances and objectives are specified in the DNRE Guidelines. • Derivation of Floodways and 1% AEP Flood Extents and recording in GIS format as for historic floods • Deliverables, reports and mapping for the Portland Basin, consisting of preparation of available flood planning and flood data mapping for rivers and streams within the basin.

The following subsections deal in more detail with the methodologies for data collection and assessment, GIS recording and interpretive mapping.

3.2 GIS Content

Table 3.1 details the GIS layers including name, features, purpose, theme and key attributes.

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Table 3.1. - GIS Data Layers

Coverage Name(1) Features Purpose Theme Key Attributes FLFEAT25 Polygon declared flood features such as declared drainage channels or floodways name, type, notes flood areas and approved flood schemes. FLXT_ XYZ Polygon, Arc features delineating historic flood extents flood extents methodology derived from flood photography, survey, etc. start date, reliability, notes FLXT_INT_ X Polygon, Arc features delineating Interpreted Maximum flood extent for flood extents reliability, notes historic floods. FLXT_STAT 9 Polygon, Arc features delineating derived (statistical) flood extents derived flood extents methodology from modelling or other means. reliability, notes FLHITE_ XY Arc, Node, features delineating observed, modelled and interpreted flood flood heights Point heights derived from flood mapping projects. FLHITE_ST 9 Arc, Node, features delineating derived (statistical) flood heights derived flood heights Point from modelling or other means. FLLEVEE25 Arc, Node centre lines and details of flood levees relevant to flood levees custodian, ownership mapping projects condition FLOODWAY25 Polygon, Arc delineating interpreted floodways floodways type of flooding FLRUNKM100 Point stream running km relevant to flood mapping projects FLSTRUCT25 Point location of man made structures on flood plains structures name, type, ownership FLFD_ XYZ Arc historic flood extent flow direction arrows FLFD_GENERIC Arc flow direction arrows for floods not associated with a particular historic flood event FLTI_ W Polygon location of areas covered by Flood Topo Data flood topo format, notes FLGI Polygon location of areas covered by Flood geology, soil maps, etc flood geology type, format FLSI_ XY Polygon location of areas covered by Satellite Photography satellite photos type, format FLPI_ XY Polygon location of areas covered by Aerial Photography aerial photos type, format

File Naming Convention: (1) XYZ = date related numerals 9 = probability of flood event W = contour interval

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4 INTERPRETIVE MAPPING

4.1 Coverage

In this section the basis for the delineation of Floodways and 1% AEP Flood Extents for the rivers systems in the Portland Basin is presented. The watercourses for which data is available, and for which interpretive mapping has been considered are outlined below:

Fitzroy River System

• Darlot Creek from Branxholme to the Fitzroy River; • Fitzroy River from upstream of Heywood to the coast; • Surrey River near Portland-Heywood Road.

In the vicinity of Portland

• Wattle Hill Creek; • Finn Street Creek.

Other individual systems

• Eumeralla River at Macarthur; • Moyne River at Port Fairy; • Belfast Lough; • Low-lying land between Port Fairy and Warrnambool (Merri River).

The towns in the Portland Basin for which Floodway and 1% AEP Flood Extent delineation was carried out at 1:5,000 scale were Macarthur, Port Fairy, and Portland.

4.2 Scope and Objectives of the Interpretive Mapping

Interpretive mapping is the process set out in the Brief to be:

“providing the best estimate of the estimate of the extent of flooding for specific areas, for a 1% AEP flood event. Maps are further enhanced by delineating floodways, showing 1% AEP flood level contours and other relevant information.”

It is expected that floodways extents will be the basis for subsequent declaration of Urban Floodway Zones or Rural Floodway Overlays under the State Planning Policy Framework (VPPs). Similarly, the 1% AEP Flood Extent will be the basis for subsequent declaration of Land Subject to Inundation Overlays (LSIO) under the VPP Framework.

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The objective of the mapping, as set out in Clause 15.02-1 of the VPPs is to assist the protection of:

• Life, property and community infrastructure from flood hazard. • The natural flood carrying capacity of rivers, streams and floodways. • The flood storage function of floodplains and waterways and floodplain areas of environmental significance.

It should be noted that areas shown as being flooded on the Flood Planning Maps and in the digital datasets may include pockets of flood free land. Conversely, there may be areas affected by flooding that have not been shown either on the maps or included in the digital datasets because there was either insufficient or no existing flood information.

4.3 Information Used

The information of most use for interpretive mapping was:

For the Eumeralla River System

• State topographical map base, STI (subject to inundation) layer; • Non-flood aerial colour photography; • Geological Survey Mapping (digital and hardcopy @ 1:250,000).

For the Fitzroy River System

• Fitzroy River Survey; • old Shire of Portland Rural Land Mapping; • Topographic Mapping (digital and hardcopy @ 1:50,000); • Geological Survey Mapping (digital and hardcopy @ 1:250,000); • Non-flood aerial colour photography.

For the Portland Area

• Portland Flood Plain Management Strategy 1998 by the Rural Water Commission of Victoria and the City of Portland; • Designated levels; • old Shire of Portland Rural Land Mapping; • Topographic Mapping (digital and hardcopy @ 1:50,000).

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For the Moyne River System

• Moyne River – Port Fairy Flooding Profiles, showing 1% AEP (1946) flood levels and profile, RWC Plan 300664, December 1990; • Moyne River – Port Fairy, Limited Flood Study and Flood Profiles, showing 1946 extent, SR&WSC Plan 135802; • , Cross Sections (and profiles) of Moyne River, SR&WSC Plan 132489; • Port Fairy Sewage Authority contour plans, Scale 1:1250, April 1979; • Port Fairy Limits of Development, floodway extent and levels, NRE plan 10940; • Geological Survey Mapping (digital and hardcopy @ 1:250,000); • Non-flood aerial colour photography. Further information regarding 1% AEP Flood Extents is available for the area around the Port Fairy Wastewater Treatment Plant, adjacent to Hamilton-Port Fairy Road and Albert Road. Contact Portland Coast Region Water Authority for details.

4.4 Criteria for Delineation of Floodways and 1% AEP Flood Extents

4.4.1 Guidelines for Delineating Floodways

The delineation of floodways was in accordance with the criteria set out in the Advisory Notes for Guidelines for Delineating Floodways (NRE, July 1998). The key criteria used to delineate floodways in the Portland Basin were as given in the following sections. As presented in Section 6 of the Guidelines, the criteria cover three main aspects:

• flooding characteristics - focuses on the definition of significant floodpath. At one level this can be defined in terms of flood hazard (depth-velocity). However, for wide floodplains, where flood plain storage has a significant function in flood attenuation, reliance on this criteria alone could result in excessive constraint on flood flows. • socio-economic factors - encompasses consideration of flood hazard and economic value of the floodplain. For the rural floodplains, economic value is relatively low and therefore floodway definition can be relatively generous. The main exception is urban floodways. • environmental values - relates to the natural flood flow distribution to wetlands and other storage areas.

The Flood Planning Maps show both rural and township areas delineated as Floodway and Land Subject to Inundation (LSI). These delineations are based on hydraulic and related considerations and therefore take no account of existing zonings or overlays. For example, floodway may be delineated over existing residential, commercial or industrial development and/or public purpose land.

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Council should apply a floodway zone (UFZ) to urban areas delineated as floodway for all cases where the land is substantially undeveloped. However, Council may consider it inappropriate to apply a floodway zoning (UFZ) over urban areas which have been substantially developed. In these areas a floodway overlay would be appropriate even if the area is no longer physically operating as floodway. Detailed local knowledge will identify such areas.

A floodway overlay would also apply over lands zoned for public purposes and delineated on the Flood Planning Maps as floodway.

Councils need to review their planning schemes in the context of FDT Project outputs and adjust or confirm zones and overlays as appropriate.

4.4.2 1% AEP Flood Extent

The delineation of 1% AEP Flood Extent is likely to be used for the LSI Overlay in municipal planning schemes and therefore shows: • significant flood storage areas that should be subject to planning control; • effluent streams that should be subject to planning control; • areas where inappropriate works which might be damaged by floods or may aggravate the impact of floods and should come under adequate planning control.

4.4.3 Use of Geological Mapping

For the Eumeralla and Moyne River Systems, the geology was used as a guide to support the use of historic, statistical or non-flood aerial photography extents for the 1% AEP flood extent and floodway.

The alluvial and paludal deposits (Qra, Qrc, and Qrm) compared reasonably well in shape with the edge of frequently wetted ground apparent from non-flood aerial photography of the area, but location was poor. Accordingly the geology was not adopted as floodway or 1% AEP flood extent.

For the Fitzroy River System, geological mapping was used to assist the delineation of Floodways and 1% AEP Flood Extent. The geological classifications of primary significance for interpretative mapping are the recent alluvial deposits. The most relevant of this group is stream alluvium (Qra) although in some areas the Malanganee Sands (Qrd and Qrs) are also significant.

Based on comparison of the geological extents with historical and interpreted extents for recorded flood events, it has been possible to draw some general conclusions regarding the relationship between geological deposits and the flood extents classifications of Floodway and 1% AEP Flood Extent.

The stream alluvium extent is considered to more closely match the extent of more frequent flooding (i.e. 20 to 40 year RI) and is comparable to Floodway extents. For extensive swamp depressions and wetlands, and major effluent watercourses, the combination of all of the recent alluvial deposits more closely represents 1% AEP Flood Extent.

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Where possible, available records of major floods and terrain interpretation from orthophotos have been used to confirm extent in association with other information.

The formation extents are as defined in the 1:250,000 Geological Survey mapping series plans which are available in digital format. It is understood that the mapping linework is more representative of 1:50,000 scale mapping than the published 1:250,000.

Hence, where other flood and terrain information is available this mapping is considered a reasonably reliable guide to interpretation at 1:25,000 but not for 1:5000 scale mapping. Comparison with orthophotos and flood photography confirms this assessment of the geological mapping reliability.

Where there is no other flood or terrain data available, the geological mapping was not used for definition of either Floodways or 1% AEP.

4.4.4 Rural Land Mapping

Rural Land Mapping (RLM) within the Basin is generally based on alluvial deposits from geological mapping and is considered to have a very low or uncertain reliability. The overall quality of the positioning of the linework/extent is quite low and whilst comparing well with geological extents the linework/extent could be in error by significantly more than ± 100 metres. While the position of the RLM extents is uncertain, the areas within the extents should be considered flood affected.

Where available and in the absence of more accurate information, Rural Land Mapping has been adopted as the 1% AEP Flood Extent.

Rural Land Mapping for the old and Shire of Portland covered many areas within the current Shire of Glenelg. Much of the RLM is based on topographic and geological features. In the absence of more detailed information and where the positional accuracy allowed, the rural land mapping was digitised directly. In some of these regions the extents were digitised in relation to digital topographic features to improve positional accuracy.

4.4.5 Impact of Levees

The impact of major levees on recorded flood extent has been considered in the delineation of floodways. The only levees in this category in the Portland Basin are:

• Regent Street on the floodplain of the Moyne River in Port Fairy. • Several levees along the lower reaches of the Fitzroy River and Darlot Creek

Generally, the 1% AEP Flood Extents have been determined without consideration of levees or other man made works.

Design levels, construction standards and maintenance regimes for most levees which are on private property and are privately owned are unreliable and inconsistent. In the main, such levees offer a level of protection well below that for a 1% AEP flood. Accordingly, the effects of all levees, other than audited public levees, have been ignored in the delineation of 1% AEP Flood Extents.

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4.5 Basis of Floodway and 1% AEP Flood Extent Delineation 4.5.1 Eumeralla River System

No flood extents or levels of any kind were available for the township of Macarthur. Therefore, non-flood aerial photography was used to delineate areas of frequently wetted land within the township. The extent derived from the photographs was similar in shape but generally wider than the STI (subject to inundation) layer of the state topographic map base.

The alignment and shape of the alluvial geology in the township of Macarthur did not compare favourably to the either the extent derived from the aerial photographs, the STI, nor any other topographic information. Hence geology was not considered appropriate for use in interpretation. No other flood data was available, consequently the extent derived from the non-flood aerial photographs was adopted as the 1% AEP Flood Extent.

Due to the absence of any sufficiently detailed ground level information and flood level information, Floodway within the township could not be determined.

4.5.2 Fitzroy River System

Within the Fitzroy River system, the only information available included the Fitzroy River Survey, the old Shire of Portland RLM, digital topography and geology, and colour non-flood aerial photography. All of these sources of information have similarly low reliability, thus the 1% AEP Flood Extent was determined using a combination of these.

No Floodway delineation was possible outside of Portland township due to a lack of flood level or detailed ground level information.

Along Darlot Creek to the Fitzroy River, and in some areas along the Surrey River, the 1% AEP Flood Extent was delineated using the old Shire of Portland RLM. The original plan on which the old Shire of Portland RLM is depicted is of very low quality. The base plan is a an enlarged photocopy of a 1:50,000 topographic plan, and the RLM is delineated with thick, hand drawn lines, and thus was deemed to be of too low quality to be used directly for 1% AEP Flood Extent interpretation. To improve the accuracy of the linework, the RLM was re-created by: • determining the methodology used to create the original RLM delineation (outlining areas subject to inundation and swamps shown on the topographic base plan using geology as a regional guide) • then applying the same methodology using digital geology and digital topographic data. This recreated RLM was adopted as 1% AEP Flood Extent along Darlot Creek.

Along the Fitzroy River upstream of Heywood, non-flood aerial photography did not show a clearly defined flood plain or frequently wetted areas. Also, alluvial geology extents in this area did not correlate with either topography or features visible in aerial photographs. As a result, the Fitzroy River Survey Edge of High Ground was seen as the only appropriate source of information, and thus was adopted as 1% AEP Flood Extents.

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Around Heywood township, the Fitzroy River Survey Edge of High Ground was also adopted as the 1% AEP Flood Extents. However, some amendments were made to identify some areas of the floodplain which were clearly shown as being frequently inundated in non-flood aerial photography.

In particular, aerial photography identified the narrow flow path through the township as being wider than shown in the Fitzroy River Survey. Also, The Fitzroy River Survey did not show a large area to the north east of the township, near Sunday Creek, as floodplain. However, this area is clearly seen as recently inundated in non-flood aerial photography. These two areas have been included in the 1% AEP Flood Extents.

It should be noted that extents around Heywood township are of low reliability. Extents shown on the 1:5000 scale map for the town are probably more representative of 1:50,000 scale mapping. They should be treated with caution, and must be verified with original source data wherever possible.

Downstream of Heywood, 1% AEP Flood Extent was generally delineated using the outer envelope of: • the Edge of High Ground extent shown on the Fitzroy River Survey, • estimation of the edge of floodplain from non-flood aerial photos, • and the re-created version of the old Shire of Portland RLM based on digital geology and topography, as described above.

The 1% AEP Flood Extents include Homerton Swamp, between Darlot Creek and the Fitzroy River. Although the Fitzroy River Survey does not show this area as floodplain, both digital topography and geology data support it being defined as subject to inundation.

The adopted 1% AEP Flood Extents downstream of Heywood and along Darlot Creek correspond well with the alluvial geology extents in the area. This further reinforces the adoption of these flood extents.

Where digital topography alone was used for interpretation, it is likely that the 1% AEP Flood Extent would be significantly greater than the given delineation, but without further investigation such extent cannot be estimated. Areas of poor drainage and therefore prone to shallow flooding do exist outside the defined 1% AEP Flood Extents.

4.5.3 Portland

Within the township of Portland extents are based on plans produced as part of the 1988 Portland Flood Plain Management Study. These plans showed the 1% ARP Flood Extent through Portland based on available 2m contours. The 1% AEP Flood Extent was based on the 1946 flood with modelling undertaken to account for subsequent conveyance and storage changes since this time. Outside of the modelled area the flood plain was adopted as the 1% AEP Flood Extent. The floodway was generally adopted as the 1% envelope given the constrained nature of the waterway with the exception that areas shown as flood Fringe “A” and “B” were excluded. All Portland extents were cross checked with historic spot levels where available.

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4.5.4 Moyne River System

1% AEP Flood Extent

Port Fairy and Belfast Lough – Because the 1946 flood is the largest on record in this region, and because very little other information exists, it seems appropriate that various authorities in the past have adopted it as the 1% AEP Flood.

A flood extent for the 1946 flood was available for areas between Belfast Lough and Gipps Street bridge which was used for the 1959 planning scheme. In these areas, the 1946 flood extent has been adopted as the 1% AEP Flood Extent.

The Moyne River 1% design flood profile, derived from estimated 1946 flood levels, is defined on RWC plan 300664 downstream of Gipps Street bridge. This profile was translated into an approximate flood extent using Sewerage Authority contour plans. The result was adopted as the 1% AEP Flood Extent along the Moyne River downstream of the Gipps Street Bridge.

As a result of the 1946 flood, mitigation works were proposed including raising the level of Regent Street in Port Fairy to act as a levee to prevent flooding to its south. The effect these works have had on the 1% AEP Flood Extent has not been taken into account. This is due to a lack of as constructed survey information confirming that the required road level of 3.2m AHD plus 300mm minimum freeboard has been achieved.

In other areas, including Belfast Lough, upstream of Belfast Lough, and areas west of the and Albert Street, 1% AEP Flood Extents have been derived using alluvial geology as a guide to the extent of flooding, and interpreting non-flood aerial photographs.

Low-lying land between Port Fairy and Warrnambool (Merri River): No flood extents or level information was available for the low-lying land between Port Fairy and Warrnambool (Merri River). Consequently, the only resources available for interpretation were non-flood aerial photos and alluvial geology extents.

Non-flood aerial photography was used to delineate frequently wetted land. The extents derived from the photographs were similar in shape but generally wider than the state topographic map base’s STI layer and alluvial geology extents, and thus was adopted as the 1% AEP Flood Extent.

Floodways

Port Fairy and Belfast Lough: Upstream of Gipps Street bridge as far as Model Lane, Port Fairy Sewerage Authority plans were available showing ground level and contour data. Using the Gipps St bridge flood level of 3.2m, these plans provided an extent similar in shape to the adopted 1% AEP Flood Extent. Therefore, Floodway was defined using the Sewerage Authority Plans as any area inundated in a 1% AEP Flood Event to at least 0.5m depth. This depth was chosen as it takes into account the highly urbanised environment in central Port Fairy, as well as the low velocity flow regime which would exist in this wide floodplain.

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Upstream of Model Lane (on both sides of the Moyne River), no ground level information was available. The best information available was non-flood colour aerial photography, which was used to delineate frequently wetted areas. These areas have been adopted as Floodway.

Downstream of Gipps Street bridge, Floodway on the west bank of the river was interpreted in the same way as the 1% AEP Flood Extent, using Sewerage Authority contour data and a 1% AEP flood profile. Along the east bank of the Moyne River south of the Gipps Street Bridge, there was a small section of floodway defined by NRE on plan 10940, and this was also adopted as Floodway.

Low-lying land between Port Fairy and Warrnambool (Merri River): Due to the absence of any sufficiently detailed flood level or ground level information, no floodway could be defined in this area on depth criteria alone.

However, part of this area acts as a flood overflow for the Merri River. In order to maintain this as an important flood storage area, the overflow path has been defined as Floodway within the only. Within Moyne Shire, the overflow path remains as 1% AEP Flood Extent without Floodway.

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5 MAPPING OUTPUT

5.1 Hard Copy Mapping

The flood mapping consisting of Flood Data and Flood Planning maps, which were prepared for the Shires within the Portland Basin, are listed in Table 5.1.

Key plans for the mapping within the Portland Basin are presented in Figures 5.1 (a to c) and Figure 5.2 for the municipalities of Glenelg, Moyne and Southern Grampians. A shaded tile indicates that a Flood Data Map and/or a Flood Planning Map has been produced for that location, but not necessarily both.

Table 5.1 - List of Map Tiles

TYPE MUNICIPALITY MAP No. TITLE SCALE Flood Data Glenelg 500500-026 Wallacedale / 25000 Flood Data Glenelg 500500-029 Hotspur / 25000 Flood Data Glenelg 500500-030 Sinclair / Milltown 25000 Flood Data Glenelg 500500-031 Breakaway Creek / Eccles 25000 Flood Data Glenelg 500500-034 Gorae / Fitzroy River 25000 Flood Data Glenelg 500500-035 Tyrendarra / Eumeralla 25000 Flood Data Glenelg 500500-038 Julia Reef / Codrington 25000 Flood Data Glenelg 500500-043 Heywood Township 5000 Flood Data Glenelg 500500-045 Portland Township 5000 Flood Planning Glenelg 500501-026 Wallacedale / Byaduk 25000 Flood Planning Glenelg 500501-030 Sinclair / Milltown 25000 Flood Planning Glenelg 500501-031 Breakaway Creek / Eccles 25000 Flood Planning Glenelg 500501-034 Gorae / Fitzroy River 25000 Flood Planning Glenelg 500501-035 Tyrendarra / Eumeralla 25000 Flood Planning Glenelg 500501-037 Portland / Narrawong 25000 Flood Planning Glenelg 500501-038 Julia Reef / Codrington 25000 Flood Planning Glenelg 500501-043 Heywood Township 5000 Flood Planning Glenelg 500501-044 Portland Township 5000 Flood Planning Glenelg 500501-045 Portland Township 5000 Flood Data Moyne 500504-006 Wallacedale / Byaduk 25000 Flood Data Moyne 500504-012 Breakaway Creek / Eccles 25000 Flood Data Moyne 500504-025 Saint Helens / Moyne River 25000 Flood Data Moyne 500504-026 / Dennington 25000 Flood Data Moyne 500504-029 Lady Julia / Port Fairy 25000 Flood Data Moyne 500504-036 Port Fairy 5000 Flood Data Moyne 500504-037 Port Fairy 5000 Flood Planning Moyne 500505-006 Wallacedale / Byaduk 25000 Flood Planning Moyne 500505-012 Breakaway Creek / Eccles 25000 Flood Planning Moyne 500505-013 Banangal / Carmichael 25000 Creek Flood Planning Moyne 500505-025 Saint Helens / Moyne River 25000 Flood Planning Moyne 500505-026 Koroit / Dennington 25000 Flood Planning Moyne 500505-029 Lady Julia / Port Fairy 25000 Flood Planning Moyne 500505-035 Macarthur 5000

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TYPE MUNICIPALITY MAP No. TITLE SCALE Flood Planning Moyne 500505-036 Port Fairy 5000 Flood Planning Moyne 500505-037 Port Fairy 5000 Flood Data Sth Grampians 500502-031 Branxholme / Violet Creek 25000 Flood Data Sth Grampians 500502-036 Wallacedale / Byaduk 25000 Flood Planning Sth Grampians 500503-031 Branxholme / Violet Creek 25000 Flood Planning Sth Grampians 500503-036 Wallacedale / Byaduk 25000

It should be noted that Flood Data Maps were only produced in areas where there was at least one historic or interpreted extent. Other data in isolation, such as levees or flood levels, did not warrant the production of a Flood Data Map.

Information contained in the Flood Data and Flood Planning maps is detailed in Table 5.2.

Table 5.2 - Flood Information and Flood Extent Contents

ITEM FLOOD DATA FLOOD PLANNING cadastral base á á topographical features (roads, streams etc) á á watercourse running distances á à levees á á CMA and municipal boundaries á á flow direction arrows à à historical & max interpretive flood extents á à historic flood levels á à flood structures à à floodways à á 1% AEP Flood Extents à á 1% AEP flood level contours à á

5.2 Digital Mapping

Digital mapping for the entire Study Area was supplied to NRE as follows:- • ARC/INFO export format • DXF & ASCII format • PDF format

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SHIRE OF 002002 003003 004004 GLENELG

005005 006006 007007 008008

011011 009009 010010 012012 041041 CASTERTONCASTERTON 042042

013013 014014 015015 016016

017017 018018 019019 020020 021021

022022 023023 024024 025025 026026

027027 028028 029029 030030 031031 PP OO RR TT LL AA NN DD BB AA SS II NN 043043 HEYWOODHEYWOOD

032032 033033 034034 035035 % 036036 037037 038038 044044 037037 038038 0 10 20 045045 PORTLANDPORTLAND Kilometres

039039 Mapping Areas 039039 040040

River Basin Boundaries

Figure 5.1a - Flood Data and Flood Planning Mapping Index Glenelg 1:25,000 and 1:5,000 Scale

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SHIRE OF MOYNE 002002 003003 004004 005005

006006 006006 007007 008008 009009 010010 011011 CARAMUTCARAMUT 011011

MACARTHURMACARTHUR 012012 013013 012012 013013 014014 015015 016016 017017 PP OO RR TT LL AA NN DD BB AA SS II NN MORTLAKEMORTLAKE HAWKESDALEHAWKESDALE

WOOLSTHORPEWOOLSTHORPE 018018 019019 018018 019019 020020 021021 022022 023023

024024 025025 026026 027027 028028

PORTPORT FAIRYFAIRY

029029 030030 031031 032032 %

0 10 20 see Fig 5.2 Kilometres 033033 034034

Mapping Areas

River Basin Boundaries

Figure 5.1b - Flood Data and Flood Planning Mapping Index Moyne 1:25,000 Scale

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SHIRE OF SOUTHERN 002002 003003 GRAMPIANS

004004 005005 006006 007007 008008

009009 010010 011011 012012 013013 014014

015015 016016 017017 018018 019019

020020 021021 022022 023023 024024 039 COLERAINECOLERAINE

DUNKELDDUNKELD 025025 026026 027027 028028 029029 % HAMILTONHAMILTON

0 10 20 030030 031031 032032 033033 034034 Kilometres PP OO RR TT LL AA NN DD PENSHURSTPENSHURST BB AA SS II NN PENSHURSTPENSHURST Mapping 035035 036036 037037 038038 Areas

River Basin Boundaries 040

Figure 5.1c - Flood Data and Flood Planning Mapping Index Southern Grampians 1:25,000 Scale

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035035 035035 MACARTHURMACARTHUR 012012 012012 013013 010144

018018 018018 019019 020200

PP OO RR TT LL AA NN DD BB AA SS II NN

024024 024024 025025 026026

036036

1:5,000 Mapping Areas 037037 PORTPORT FAIRYFAIRY

River Basin Boundaries

Figure 5.2 - Flood Data and Flood Planning Mapping Index Moyne 1:5,000 Scale

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6 ASSESSMENT OF DATA AND CONCLUSIONS

6.1 Assessment of Data and Interpreted Extents

6.1.1 Data Reliability

The reliability of the data entered into the GIS was in accordance with the NRE’s Guidelines on Assessing Reliability, April 1998. In general, it is recommended that where required for accuracy reasons, the source data be reviewed to confirm the accuracy of the GIS.

6.1.2 1% AEP Flood Extent Delineation Reliability

The Guidelines give a detailed description of the basis of three grades, HIGH, MEDIUM and LOW which leave room for judgement of the confidence limits of the linework (Refer Table 14 of the Guidelines. These guidelines can be translated back to spatial confidence limits which are presented in the Guidelines for consideration of historical event recording as: • HIGH - ± 50 metres • MEDIUM - ± 100 metres • LOW - greater than ± 100 metres

Whilst the Guidelines give two detailed methodologies for determining the delineation reliability, it is concluded that the general quality of the data in most cases precludes the use of any other grade than LOW. In some cases where there are well defined topographic features, a grading of MEDIUM would be possible. However, such cases are quite rare and therefore of little consequence. This conclusion is based on the following general limitations in the data and digital conversion process: • Raw Data Limitations - photographed extent not at maximum; - recorded event not close to 1% AEP; - poor quality photography (clouds, reflection, obliques, etc); - poor quality mapping (lack of documented basis, notional appearance, presented without reference to topography, scale too large, etc) - lack of associated orthophoto and/or contour mapping. • Conversion to Digital Format - georeferencing distortions (tolerance of not greater than ± 60 metres was generally achieved); - disparities in digital base mapping (differences in waterway alignments between cadastral and rivers and streams topography mapping and also geological mapping).

It was concluded that to differentiate the available data would require an additional grade of VERY LOW (for say ±500 metres)

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A summary of the reliability assessments of 1% AEP Flood Extents is presented as follows: • Eumeralla River System – Low throughout - the estimated 1% AEP Flood Extent is based on interpretation from non-flood aerial photographs. • Moyne River System – Low to Medium - The estimated 1% AEP Flood Extent is based on Port Fairy Limited Flood Study and Flood Profiles, interpretation from non-flood aerial photographs, and geological mapping, and site visits. The Moyne River 1% AEP Flood Extent north of the Gipps Street bridge and south of Manifold Street in Port Fairy is considered to be medium reliability. Although the digital datasets do not allow Floodway reliabilities to be assigned, the Floodway near Model Lane and upstream should be considered to be low reliability, and downstream to Gipps Street bridge and beyond can be considered medium reliability. • Fitzroy River System - LOW - The estimated 1% AEP Flood Extent is based on geological mapping, digital topographic data, non-flood aerial photography, and information from a 1933 River Survey. • Darlot Creek – LOW - The 1% AEP Flood Extent was based on the old Shire of Portland RLM, originally derived from 1:50,000 topographic data and geology. • Portland township – LOW / MEDIUM – Within the township the 1 % extent is based on relatively high reliability modelled flood height contours and existing 2m ground surface contours (expected to be accurate to half the contour interval ie 1m vertical). Extents derived using these 2 m ground surface contours and the modelled 1% flood height contours have been assigned a MEDIUM reliability. The 1% extent beyond this region is based on the flood plain extents and no modelling, therefore this region has been assigned a LOW reliability.

6.2 Conclusions

6.2.1 Application of Mapping

The available flood mapping for the Portland Basin is a relatively good coverage in terms of flooding problems. However, the quality of mapping is mixed with only some areas having a HIGH grading quality. Hence, where it can be justified in terms of identified flood damage or potential flood damage, further work should be carried out to improve the quality of 1% AEP Flood Extent and Floodway extent mapping.

The Flood Data maps should only be used for identifying the location of past flood problem areas. The extents on the Flood Data Maps should not be used for planning purposes without further investigation and confirmation.

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6.2.2 Co-ordination and Referral

There is a strong case for considering the management of the streams within the Portland Basin be co-ordinated between the municipalities and CMAs. There are a total of three municipalities and the Glenelg Hopkins CMA with responsibility for parts of the Portland Basin.

It is essential that the three municipalities and the CMA in the Portland Basin adopt similar approaches and rules for considering development applications and establish a clear process of referral.

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7 BIBLIOGRAPHY

Rural Water Commission of Victoria and City of Portland (1988). Portland Flood Plain Management Study

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MAPPING METHODOLOGY DEPARTMENT OF NATURAL RESOURCES AND ENVIRONMENT River Basin Report - Portland Basin

1. SUMMARY OF METHODOLOGY

The overall process adopted for dealing with the flood mapping and other information is given in Figure A.1.

Data Collection Cataloguing and Assessment

Data Management and Control

The project brief required use of an MS-Access database to manage DNRE’s flood plans of relevance to Egis Consulting's data capture area. Information collected from municipalities, CMAs and other authorities and agencies is similarly managed.

The main function of the database was to allow tracing of documents through the project tasks, and to assist in the development of a new Catalogue system for DNRE’s continued use upon completion of the project.

The information collected was that which was readily available without extensive searches for and research of flooding information.

VV8159.090 VV8159.090.Rev0 A.1 DEPARTMENT OF NATURAL RESOURCES AND ENVIRONMENT River Basin Report - Portland Basin

Figure A.1 - GIS Mapping Steps

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2. DATA ASSESSMENT

The Metadata requires extraction of information under the following categories: 1. flood extents (historical, statistical, interpretive); 2. levees (location, custodianship, ownership, heights); 3. flood heights (historical or calculated); 4. structures (culverts, syphons, bridges, regulators, weirs, retarding basins); 5. floodways (derived and declared); 6. features (declared or approved drainage course, flood extent or level area); 7. running river distances; 8. flow direction.

All mapping, data and other information received was assessed for suitability for including in the GIS. The information included:

Type of Information Used in GIS for delineating or defining: vertical flood photography (usually flood extents, floodways, structures available in mosaics in B&W, colour or infra-red) oblique flood photography (colour, flood extents, floodways, structures B&W) flood mapping from previous flood extents, floodways, structures interpretation of flood photography flood investigation reports flood extents and levels, floodways, structures, flow direction flood history mapping and reporting flood extents and levels, structures, flow direction topographical survey on orthophoto flood extents and levels, floodways background structures historical flood level recordings from flood levels, structures CMA, municipality, Vic Rail, Vic Roads etc. files

Generally, where information could be transferred into the GIS and was not deemed in conflict with other information it was included. Specific exclusions were: • same information was already available from a more reliable source; • quality of information was ambiguous and of such poor quality that it may be misleading; • location of culverts and other structures relating to local drainage; • all recorded levee bank heights or levels (included only representative number).

Approval from DNRE was sought and received for significant data exclusions relating to interpretation of information quality and ambiguity.

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3. FLOOD MAPPING AND GIS RECORDING

Process and Software Applications

The conversion of flood data and other information into a GIS format has the following major steps: 1. Background scanning and registration 2. Flood data interpretation 3. Digitising of flood data 4. Building of GIS Models 5. Preparation of Hardcopy Outputs

These major steps are described in more detail in the following sections.

The software used in the process were:

Software Description Applied in: TNT-mips High end, high powered, GIS georeferencing, registration, Version 5.9 and mapping software. rubbersheeting, clean and building of layers, integrity checks, formation of digital files suitable for importation to ArcInfo Microstation CAD software reading and manipulating produced digital mapping MapInfo Entry level GIS and mapping digitising and attributing of flood Version 4.0 software. information, production of hard copy output

Scanning, and Georeferencing in TNT-MIPS

The various flood mapping information were assessed for scanning suitability. In some cases, in particular for certain black and white air photography, some boundary delineation was required using Chinagraph or other appropriate markers.

Registration of the scanned images to the cadastral base was carried out by identifying up to 12 control points on the scanned image and “matching” these to the equivalent cadastral points. This process called rubbersheeting / resampling removes image distortion by tying down known control points on a scanned Raster image to known cadastral coordinates, resulting in stretching/compression of the image. In some instances, it was necessary to subdivide the image and undertake separate referencing.

The registered scanned Raster images were then exported to MapInfo for digitising and attributing the relevant information.

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Digitising/Attributing in MapInfo

In accordance with the Metadata, the information contained in the scanned Raster images was converted through digitising and attributing into vectors (points, lines, polygons) data, and stored in a series of theme based master GIS layers. The themes recorded comprised: • flood extents - historical, statistical and interpreted; • floodways - interpreted type, extent and location; • levees - name, ownership, custodianship, location and levels; • structures - name, type; • flood heights - contour, spot height, declared, documented

The structure of GIS layers is defined in detail in DNRE’s Metadata standards. The main aspects of the Metadata are summarised in Table 3.1.

A number of Index layers where also developed. The Indices further categorise relevant source data into Aerial Photography, Satellite Photography, Geological, and Topographic themes.

Polygon Aggregation

As required by the NRE Metadata Standards, digital data is supplied as arcs and polygons for the Flood Extent (FLXT_XYZ, FLXT_INT_X, FLXT_STAT9) layers. For the Declared Floodways (FLOODWAY25) and Declared Features (FLFEAT25) layers, only polygons are required.

For all of the above layers, the attribute data was assigned to the arcs only during data collection. Polygons were then formed from the arcs by an automated polygon aggregation process. The process aggregates the attribute data assigned to the arcs to form a single set of attribute data for each polygon as outlined in Table A.1 below.

Table A.1 Polygon Aggregation Calculation Methods For FLXT_XYZ, FLXT_INT_X & FLXT_STAT9 FlevntID Min value Flextt Value with Maximum arc count Fldextid Value with Maximum arc count Flextsdt Value with Maximum arc count Flextstm Value with Maximum arc count Flextfdt Value with Maximum arc count Flextftm Value with Maximum arc count Statn_id Value with Maximum summed line length Flmeth Value with Maximum arc count Flrel Avg weighted by line length Flplnnbr Value with Maximum arc count Flatscl Value with Maximum arc count Fldeptid Value with Maximum arc count Flrep Value with Maximum arc count Flnoteid Value with Maximum arc count and not 0 (Approx) Flextver Max value For FLOODWAY (Polygons only) FlwayNID Value with Maximum arc count Flwaytyp Presumed identical for Poly. Therefore first value assigned Flnoteid Value with Maximum arc count. flwayver Max value

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For FLFEAT25 (Polygons only) Flfnamid Value with Maximum arc count Flftyp Presumed identical for Poly. Therefore first value assigned Flfstart Presumed identical for Poly. Therefore first value assigned Flnoteid Value with Maximum arc count Flplnnbr Value with Maximum arc count Flfeatver Max value

It is important to note that the FDT metadata requires only polygons for the Floodway and Features layers. Underlying arc attribute data has therefore not been included in the digital datasets.

Random manual checks of the polygon attribute data were made to ensure that the data created by the polygon aggregation process reasonably represents the original arc attribute data as captured. Flood notes were created manually for polygons where it was deemed appropriate to attach a note.

Users of the digital data should note that for detailed analyses precedence must be given to the arc attribute data over the polygon attribute data where available.

GIS Outputs

Following validation and cleaning, the GIS layers were prepared for presentation in both digital and hard copy format. The details of the format requirements are:

For Hard Copy Format

• two map series, one for Flood Information (i.e. maps displaying historical information) and one for Flood Extent (i.e. maps displaying derived information); • B1 size map series at a scale of 1:5000 for towns on a suitable tile grid to match town layout • B1 size map series at a scale of 1:25,000 based on standard topographic mapping tiles, to municipality boundaries; • having a base layer of cadastral and topographic information including roads, major drainage alignments, towns, etc.

The relevant whole and part map tiles are detailed in Section 5.0 of this report.

For Digital Format

Each coverage or layer (described in Table 3.1) was supplied as a separate file covering the whole of Egis Consulting's study area. The following data formats were supplied;

• ARC/INFO export files (.e00 files); • DXF & associated ASCII attribute file; • PDF Format for map viewing and printing

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4. DATA CATALOGUING

The Project Brief required Egis Consulting to re-organise and re-catalogue existing hard copy plans held by NRE in their Box Hill Office. The purpose of re-cataloguing hard copy data was to present it in a more logical and useable form.

The approved cataloguing system divides the existing plans into two Categories:

Category 1 Plans

These are planning scheme maps, flood maps completed on a municipal basis, and irrigation works plans, and stored by: • Primary key - Municipality • Secondary key - Information Type (planning scheme maps, flood maps, irrigation works plans)

Category 2 Plans

All other plans fall into Category 2, and will be stored by: • Primary key - River Basin • Secondary key - Stream/Subcatchment

Plans extending over more than one basin/municipality/type of information the plans were stored under the predominant basin, municipality or information type with reference in the database to the secondary areas.

The divider structure for the Portland Basin is as defined below:

BY MUNICIPALITY: Glenelg, Moyne and Southern Grampians.

Information type (one divider within each municipality): planning scheme maps, municipal based flood maps, irrigation works plans.

BY SUBCATCHMENT:

- Eumeralla River - Fitzroy River - Moyne (including Port Fairy) - Portland

VV8159.090 VV8159.090.Rev0 A.7 APPENDIX B

CONTACTS CONTACTS NRE FLOOD DATA TRANSFER PROJECT

ORGANISATION CONTACT CONTACT 2 PHONE FAX E-MAIL ADDRESS SUBURB PCODE DX NO. Glenelg Shire Council Lionel Shelton Engineer Portland (03)5522 2247 PO Box 152 PORTLAND VIC 3305

Andrew Loader Engineer Portland (03) 5522 2200 Moyne Shire Council George Borg Planning Department Scot Elliott 5568 2600 PO Box 51 PORT FAIRY VIC 3284 Southern Grampians Shire General Manager Southern 5573 0456 Locked Bag 685 (111 Council Mr Gary Van Driel Grampians Services 5573 0444 5572 2910 Brown Street) HAMILTON VIC 3300 Glenelg Hopkins Catchment Management Authority Janet Lowe Floodplain Manager 5571 2526 5571 2935 49 Thompsons Road HAMILTON VIC 3300 30015

Others

ORGANISATION CONTACT CONTACT 2 PHONE FAX E-MAIL ADDRESS SUBURB PCODE DX NO.

5139 3100 Geoff 5139 3155 JC Southern Rural Water John Cameron Wheaton 5139 3133 GW 5139 3150 [email protected] PO Box 153 MAFFRA VIC 3860 VicRoads Mike Verey 60 Denmark Street KEW VIC 3101 Rail Group, Sinclair Knight Mike 9248 3100 PO Box 2500 (Level 1, MALVERN VIC 3144 Merz David Patterson Executive Engineer Commons 9248 3208 MC 9248 3535 590 Orrong Road) (ARMADALE VIC) (3143)

General Manager Asset GPO Box 1681P (Level 3001 Vic Track Access Russell Trevaskis Management 9619 8847 9619 8851 17, 589 Collins Street) MELBOURNE VIC (3000) Level 1, 240 Victoria EAST MELBOURNE NRE Ian Gauntlett 9412 4687 Pde VIC 3002 Bureau of Meteorology Kevin Songberg 9669 4900 GPO Box 1636M MELBOURNE VIC 3001 [email protected] Department of Infrastructure Robert Fisher 9655 6666 9655 6752 c.gov.au

Contacts for Reports.xls Appendix B, VV8159.090.Rev0 Page 1 of 1