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ATTACHMENT 2
LOCAL FLOODPLAIN RISK MANAGEMENT POLICY
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CONTENTS
1
Contact Details ....................................................................................... 3
2
Background ............................................................................................ 3
3
Information that council provides ........................................................ 4
4
Why has this Policy been prepared? ................................................... 4
5
Floodplain Risk Management ............................................................... 5
5.1
Flood mitigation ....................................................................................... 5
5.2
Land use planning ................................................................................... 6
5.2.1
5.3
6
Foreshore Building Line ....................................................................................... 6
Flood education ....................................................................................... 9
What your flood category means ......................................................... 9
6.1
High Flood Risk Precinct......................................................................... 9
6.2
Medium Flood Risk Precinct ................................................................. 10
6.3
Low Flood Risk Precinct ....................................................................... 10
7
Flood Planning Level ........................................................................... 11
8
Development Control & the Planning Matrix ..................................... 11
8.1
8.1.1
8.1.2
8.1.3
General Principles for Development on Flood Liable Land ................ 11
Objectives .......................................................................................................... 11
Design Principles ............................................................................................... 12
Design Standards .............................................................................................. 13
9
Voluntary House Purchase & Voluntary House Raising .................. 17
10
Gratuity for Relocation Expenses associated with Voluntary House
Purchase............................................................................................... 18
11
What do the terms in this Policy mean? ............................................ 18
Parramatta City Council
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1 CONTACT DETAILS
Version
Date prepared Prepared by
2
15 / 02 / 2006
Project Officers –
Outcomes & Place
Unit and Land Use
& Transport
Planning Unit
Approved
by
Waterways
Systems
Manager
Date
adopted
Enquiries:
Parramatta City Council
30 Darcy Street, Parramatta NSW 2150
PO Box 32 Parramatta NSW 2124
Website:
www.parracity.nsw.gov.au
Development Enquiries:
(02) 9806 5000 (main switch)
2 BACKGROUND
Flooding is a significant issue that affects existing and future developments in
the Parramatta Local Government Area (LGA). This Policy establishes
Council’s approach to floodplain planning and the general requirements
relating to development control for the whole LGA.
The primary objective of the NSW Government’s Flood Prone Land Policy is:
“to reduce the impact of flooding and flood liability on individual owners
and occupiers of flood prone property, and to reduce private and public
losses resulting from floods, utilising ecologically positive methods
wherever possible.”
The NSW Government’s Flood Plain Development Manual (FDM) 2005,
supports the NSW Government’s Policy in providing for the development of
sustainable strategies for managing human occupation and the use of the
floodplain considering risk management principles. The development of
Council’s approach to flooding has regard to and complies with the process
outlined in the FDM. This Local Floodplain Risk Management Policy (herein
referred to as the Policy) applies the flood risk management principles of the
NSW Government at a local level.
Flooding involves significant risks to life and property. Flood risks cannot be
eliminated, but they can be avoided, minimised and responded to accordingly.
The primary application of floodplain risk management is through the
appropriate control of development within the floodplain.
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This Policy describes the principles relating to:
(a) The preparation of flood risk management plans;
(b) Provision of flood information to the community; and,
(c) Development control in the floodplain.
This Policy should be read in conjunction with all relevant council plans and
policies. These include:






The NSW Government Flood Prone Land Policy;
The NSW Government Floodplain Development Manual (FDM) 2005;
Environmental Planning and Assessment Act, 1979;
Sydney Regional Environmental Plan No 28 – Parramatta;
Parramatta Local Environmental Plan;
Parramatta Local Environmental Plan (Heritage and Conservation Plan);
and,
The relevant Development Control Plans for the City of Parramatta.

Note: Consistent with the FDM, this Policy does not apply in
circumstances of local drainage inundation as defined in the FDM and
determined by Council. Local drainage problems can generally be
minimised by the adoption of urban building controls requiring a
minimum difference between finished floor and ground levels.
3 INFORMATION THAT COUNCIL PROVIDES
Council provides the following information to the community:




Guidance and interpretation of this Policy;
Flood Risk Management Plans, developed in association with a local
floodplain risk management committee;
Advice for developing on Flood Prone Land within the LGA; and,
Flood Levels and Flood Risk Precincts.
4 WHY HAS THIS POLICY BEEN PREPARED?
This Policy has been prepared for the Parramatta LGA because Council is the
primary authority responsible for land use planning and the provision of floodrelated information.
The Policy has regard to the New South Wales Government’s FDM. The
FDM provides guidelines for the implementation of the NSW Government’s
Flood Prone Land Policy and outlines the procedures for developing
Floodplain Risk Management Plans for all water catchments within the LGA.
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The steps for preparing and implementing a Floodplain Risk Management
Study and Floodplain Risk Management Plan are depicted by Figure 1 below.
Figure 1: Floodplain Risk Management Process (FDM, April 2005)
Floodplain
Risk
Management
Committee
Data Collection
Flood Study
Floodplain
Risk
Management
Study
Floodplain
Risk
Management
Plan
Implementation
of Plan
5 FLOODPLAIN RISK MANAGEMENT
The various flood studies, plans, policies and standards provide an equitable
and consistent approach for land affected by potential floods, in accordance
with the principles contained in the FDM.
Floodplain risk management is about occupying the floodplain and optimising
its use in a manner which is compatible with the flood hazard and at a level of
risk which is accepted by the community. Floodplain Risk Management Plans
are the instruments which apply specifically to each catchment within the LGA
and set out the relevant controls and actions for the optimal use of the
floodplain.
For those floodplains and catchments for which a Floodplain Risk
Management Plan has not yet been prepared, this Policy provides measures
to manage flood-related risks, in a manner consistent with the current FDM.
Council applies 3 types of responses to flood risk issues. They are flood
mitigation (structural measures to reduce flood impacts), land use planning
and flood education.
5.1 Flood mitigation
Council has a comprehensive flood mitigation program that includes a
prioritised project database. All flood mitigation projects are defined by
previous flood studies and flood risk management plans, and priority projects
are identified in Council’s management plan.
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5.2 Land use planning
The control and management of land use provides the most effective means
of managing the consequences of flood and hence, minimising flood risks.
For example, the consequences of a hospital being subject to increased
depths of fast moving floodwaters with no warning has been determined as an
unacceptable risk to the community, while shallow backwater flooding of a
plant nursery with adequate warning times may be considered an acceptable
risk.
Council’s land use zones determine the appropriate type of use for flood liable
land. The building design then has to appropriately respond to the sitespecific flood constraints. The building design considerations are outlined in
the applicable development controls for flood liable land. They include
various objectives, design principles and design standards to achieve the
principles of the FDM. In particular the design standards utilise a planning
matrix approach to convey the specifications required. The matrix of
development controls, based on the flood risk and the land use, aims to
balance the risk exposure across the floodplain and ensure design of the
development responds adequately to the flood situation.
5.2.1
Foreshore Building Line
An important part of land use planning is to define the land where it is
undesirable to build. The Parramatta Local Environmental Plan and Regional
Environmental Plan include a Foreshore Building Alignment based on a 25metre setback from the Parramatta River. The Foreshore Building Line is
applied primarily to preserve the scenic qualities of the River.
In future amendments to the Environmental Planning Instruments the
Foreshore Building Line may be amended to include three areas where
planning controls are desirable, these being:

To identify, preserve and enhance important vegetation communities by
the restriction of development and consequent clearing within these
areas and associated buffer areas. Suggested buffers been provided in
Table 1 for each type of vegetation. The areas mapped by the
consultant may require refinement during the process of defining the
foreshore building line to take into consideration on-site practical
difficulties in implementing buffer areas where they extend into areas of
existing extensive development.

To provide an open setback area from the waterway corridors, within
which minimal development occurs and a predominance of landscaping
prevails, to provide for the preservation and enhancement of the scenic
qualities of these corridors. This line is based on the existing Foreshore
Building Line.

To identify the areas of high flood risk within the Flood Risk Precinct
maps where new development is generally undesirable and
redevelopment and alterations and additions to existing buildings must
be stringently controlled to minimise potential damages to property and
risk to human life.
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It is recognised that the foreshore building line effectively represents a
development standard, and Council may from time to time need to exercise
appropriate flexibility in varying the setback restrictions of the foreshore
building line, through the application of State Environmental Planning Policy
No. 1 – Development Standards. The provision of an objective will be
important in assessing any objections to the standard.
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Table 1: Recommended Vegetated Buffers for the Foreshore Building Line
Vegetation Type
Rainforest
Swamp Oak
Disturbed
Riparian
Vegetation
Adopted
Single
Medium MultiPrivate
Public
Road
Commercial Industrial
Buffer
Residential Density, storey
Open
Open Reserve
Width
Development
Town
Units Space/park Space
House,
etc
Villas
20
20 - 25
20 - 30
20 10
10
10 - 15
20 - 30
30
30
10
10
10
10
5 - 10
5
5 - 10
10 - 15
10 - 15
15
10 - 15
15 - 20
15 10 - 15
10
10 - 15
20 - 30
30
20
Open
Forest/Woodland
10
10
10 - 20
10 20
5 - 10
5 - 10
10
20
20
Mangroves
25
20
25 - 30
25 30
20
15
25
30
30 - 50
Sedgeland
30
20 - 30
30 - 40
30 –
40
20
15 –
20
20 - 30
30 - 50
50
Saltmarsh
30
20 - 30
30
30
20
15 20
20 - 30
30 - 50
50
Note: buffer widths are regarded as estimates and as a minimum. Site specific assessments will be necessary
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5.3 Flood education
Council seeks to provide information to raise awareness of the flood problem
so as to enable individuals to understand how to manage themselves and
their property in response to flood warnings and in a flood event. It invokes a
state of flood readiness, which allows the individual to react within an
appropriate time.
6 WHAT YOUR FLOOD CATEGORY MEANS
Land within each of the floodplains within the LGA can be divided into flood
categories based on the different levels of potential flood risk. The relevant
Flood Risk Precincts (FRP’s) for each of the floodplains are outlined below. A
property may be subject to more than one FRP.
6.1 High Flood Risk Precinct
The high flood risk precinct is where high flood damages, potential risk to life,
evacuation problems are anticipated or development would significantly and
adversely affect flood behaviour. Within this precinct there exists a significant
risk of flood damages without compliance with flood-related building and
planning controls. Hence, the majority of development should be restricted in
this precinct.
This has been defined generally as the area of land below the 100 year flood
that is either subject to a high hydraulic hazard or where there are significant
evacuation difficulties.
HIGH
Figure 1: High Flood Risk Precinct
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6.2 Medium Flood Risk Precinct
A significant risk of flood damage exists in the medium flood risk precinct, but
these damages can be minimised by applying appropriate development
controls. Generally, this has been defined as land below the 100 year flood
that is not subject to a high hydraulic hazard and where there may be some
evacuation difficulties.
MEDIUM
Figure 2: Medium Flood Risk Precinct
6.3 Low Flood Risk Precinct
The low flood risk precinct is that area above the 100 year flood and most
land uses would be permitted within this precinct. Although a risk of flood
damages exists, appropriate planning and building controls can minimise the
risk to an acceptable level.
This area has been defined as all other land within the floodplain (i.e. within
the extent of the probable maximum flood) but not identified within either the
high flood risk or the medium flood risk precinct.
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LOW
Figure 3: Low Flood Risk Precinct
7 FLOOD PLANNING LEVEL
The Flood Planning Level (FPL) is the level below which Council places
restrictions on development due to the hazard of flooding. The adopted FPL
used for planning controls purposes is derived from a combination of the 100
year Average Recurrence Interval (ARI) flood event level and a freeboard of
500mm, i.e. the 100 year ARI flood level plus an additional 500 mm height.
8 DEVELOPMENT CONTROL & THE PLANNING
MATRIX
The criteria for determining applications for proposals potentially affected by
flooding are structured in recognition that different controls are applicable to
different land uses and levels of potential flood inundation and hazard.
8.1 General Principles for Development on Flood
Liable Land
8.1.1
Objectives
O.1
To ensure the proponents of development and the community in
general are fully aware of the potential flood hazard and consequent
risk associated with the use and development of land within the
floodplain.
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O.2
To require developments of high sensitivity to flood risk (e.g. critical
public utilities) be located and designed such that they are subject to
no or minimal risk from flooding and have reliable access.
O.3
Allow development with a lower sensitivity to the flood hazard to be
located within the floodplain, subject to appropriate design and siting
controls, provided that the potential consequences that could still
arise from flooding remain acceptable having regard to the State
Government’s Flood Policy and the likely expectations of the
community in general.
O.4
To prevent any intensification of use within a High Flood Risk Precinct
or floodway, and wherever appropriate and possible, allow for the
conversion to natural waterway corridors.
O.5
To ensure that the proposed development does not expose existing
development to increased risks associated with flooding.
O.6
To ensure that design and siting controls required to address the
flood hazard do not result in unreasonable impacts upon the
character, amenity or ecology of an area.
O.7
To minimise the risk to life by ensuring the provision of appropriate
access from areas affected by flooding up to extreme events.
O.8
To minimise the damage to property, including motor vehicles, arising
from flooding.
8.1.2
Design Principles
P.1
The proposed development should not result in any increased risk to
human life.
P.2
The additional economic and social costs which may arise from
damage to property from flooding should not be greater than that
which can reasonably be managed by the property owner, property
occupants and general community.
P.2
The proposal should only be permitted where effective warning time
and reliable access is available for the evacuation of an area
potentially affected by floods to an area free of risk from flooding.
Evacuation should be consistent with any relevant flood evacuation
strategy where in existence.
P.3
Development should not detrimentally increase the potential flood
affectation on other development or properties, either individually or in
combination with similar developments that are likely to occur within
the same catchment.
P.4
Motor vehicles are able to be relocated, undamaged, to an area with
substantially less risk from flooding, within an effective warning time.
P.5
Procedures would be in place, if necessary, (such as warning
systems, signage or evacuation drills) so that people are aware of the
need to evacuate and relocate motor vehicles during a flood and are
capable of identifying the appropriate evacuation route.
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P.6
Development should not result in significant impacts upon the
amenity of an area by way of unacceptable overshadowing of
adjoining properties, privacy impacts (eg. by unsympathetic house
raising) or by being incompatible with the streetscape or character of
the locality (including heritage).
P.7
Proposals for raising of structures must provide appropriate
documentation including a report from a suitably qualified engineer to
demonstrate the raised structure will not be at risk of failure from the
forces of floodwaters.
P.8
Proposed development must be consistent with Ecologically
Sustainable Development (ESD) principles. The proposed design
must ensure it does not compromise ecological function.
P.9
The proposal must not constrain the orderly and efficient utilisation of
the waterways for multiple purposes.
Note: An evacuation plan is not sufficient to negate compliance with all
building regulations.
8.1.3
Design Standards
All proposals are to have regard to the planning matrix. The procedure to
determine which designs standards apply to proposed development involves:
i.
identifying the land use category of the development from the Land
Use Category Definitions table that follows;
ii.
identifying the relevant floodplain and flood category of the land (refer
to Catchment Management Unit of Council for the Flood Risk Precincts
and relevant flood risk mapping ); and
iii.
applying the objectives, design principles and design standards, as
outlined in this section.
The planning matrix below outlines the design standards relevant to each of
the floodplains to which this Policy applies.
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Table 2: Land Use Category Definitions
Land Use
Categories
Sensitive Uses
and Facilities
Critical Utilities
and Uses
Subdivisions
Filling
Residential
Commercial or
Industrial
Tourist Related
Development
Open Space or
Non-urban
Uses
Definitions
Community facilities or public buildings which may provide an important
contribution to the notification and evacuation of the community during
flood events; centre-based child care services; Hospitals; Housing for
older persons or persons with a disability; Educational establishments;
Institutions; and Nursing Homes.
Hazardous industry or storage establishments; Offensive industry or
storage establishments; Liquid fuel depots; Public utility undertakings
(including generating works) which may cause pollution of waterways
during flooding, are essential to evacuation during periods of flood or if
affected during flood events would unreasonably affect the ability of the
community to return to normal activities after flood events;
Telecommunication facilities; Transfer stations; waste facilities and waste
processing facilities.
Subdivision of land which involves the creation of additional allotments.
The net importation of fill material onto a site, except where:
i. final surface levels are raised by no more than 100mm over no
more than 50% of the site; or
ii. filling is no more than 800mm thick beneath a concrete building
slab only.
Compensatory earthworks, involving cut and fill, is not considered to be
filling provided that:
i. there is no net importation of fill material onto the site; and
ii. there is no net loss of flood storage at all flood levels.
Backpackers’ accommodation;
Bed and breakfast establishments;
Boarding houses; Businesses; Community facilities (other than sensitive
uses and facilities); Dual occupancies; Dwelling-houses; Granny flats;
Group homes; High density housing; Home-based child care services;
Home occupation; Local shops; Medical consulting rooms; Multi-unit
housing; Professional consulting rooms; Recreation establishments;
Residential flat buildings; Serviced apartments; Special home activities;
terrace housing; and Utility installations (other than critical utilities)
Brothels; Bulky goods retailing; Car parking stations; Car repair stations;
Churches; Clubs; Commercial premises; Community drop-off centres;
Depots; Entertainment facilities; Equipment hire centres; Health care
professional buildings; High technology industries; Hotels; Industry; Light
industry; Materials recycling depots; Medical centres; Motels; Motor
showrooms; Panel beating shops; Places of worship; Public buildings
(other than an essential community facility); Public transport facilities;
Recreation facilities; Remote distribution centres; Restaurants; Resource
Recovery facilities; Restricted premises; Road transport terminals;
Service stations; Shops; Television stations; Vehicle rental centres;
Veterinary establishments; Transport and Warehouse or distribution
centres.
Kiosk; Market and Tourist facilities.
Animal establishments; Boatsheds; Extractive industries; Forestry; Grain
transport depots; Helipads; Jetties; Mines; Mineral sand mines;
Recreation areas and minor ancillary structures (e.g. toilet blocks or
kiosks); Retail plant nurseries; Roadside stalls; and Slipways.
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Land Use
Categories
Concessional
Development
Definitions
Concessional development is any development or redevelopment that
would normally not be permitted under this Plan, but may be permitted as
a concession provided it:
i. is kept clear of any floodway; and
ii. involves an acceptably small (see below for limits) addition or
alteration to an existing development that will not cause no
significant increase in potential flood losses or risks or adverse
impact on adjoining properties; or
iii. redevelopment for the purposes of substantially reducing the
extent of flood affectation to the existing building provided that
such redevelopments incorporate to the fullest extent practical,
design features and measures to substantially reduce the
existing potential for flood losses and personal risks, and avoid
any adverse impacts on adjoining properties – especially
obstruction or diversion of floodwaters and loss of flood storage.
In the case of
residential development, the maximum size of a
concessional development is:
i. a once-only addition or alteration to an existing dwelling of no
more than 10% or 30m2 (whichever is the lesser) of the habitable
floor area which existed at the date of commencement of this
Policy or Plan; or
ii. the construction of an outbuilding with a maximum floor area of
20m2.
In the case of other development categories, the maximum size of a
concessional development is a once-only addition to existing premises of
no more than 10% of the floor area which existed at the date of
commencement of this Policy or Plan.
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FLOODPLAIN MATRIX
Planning & Development Controls
Flood Risk Precincts (FRP's)
Open Space & Non-Urban
Concessional Development
1
1
1
1
1
1
1
2
2, 4, 6
5
Management & Design
2, 3, 4
1
2
2
1, 3,
5, 6
Not
Relevant
1
Sensitive Uses & Facilities
Residential *
Critical Uses & Facilities
Flood Affectation
Car Parking & Driveway
Access
Evacuation
2
2
2
1, 3,
5, 6
1, 3,
5, 6
1, 3,
5, 6
1
3, 4
4
4
2, 4,
6, 7
5, 3, 4
1
Unsuitable Land Use
*
Tourist Related Development
1
Commercial & Industrial
1
Residential *
1
Subdivision
2
Filling
Structural Soundness
Critical Uses & Facilities
Concessional Development
1
Sensitive Uses & Facilities
Open Space & Non-Urban
Building Components
2, 5
Residential *
4, 5
1
Filling
1, 5
1
Subdivision
4, 5
1
Critical Uses & Facilities
1, 5
1
2, 5
Concessional Development
2, 5
1
2, 5
Open Space & Non-Urban
2, 5
1
Commercial & Industrial
2, 5
2
Filling
3
Subdivision
Floor Level
Planning
Consideration
Sensitive Uses & Facilities
Tourist Related Development
High Flood Risk
Commercial & Industrial
Medium Flood Risk
Tourist Related Development
Low Flood Risk
1
1
1
1, 3,
1, 3,
1, 3,
5, 6, 7 5, 6, 7 5, 6, 7
2, 4,
6, 7
1, 5
2, 4,
6, 7
1, 5
3, 4, 6 3, 4, 6 3, 4, 6
1, 4
3, 6
1, 4
3, 4, 6
2, 3, 4 2, 3, 4 2, 3, 4 2, 3, 4 2, 3, 4
2, 3, 4 2, 3, 4
For redevelopment of an existing dwelling refer also to 'Concessional Development' provisions
Floor Level
1
2
3
4
5
All floor levels to be equal to or greater than the 20 year ARI flood level plus freeboard.
Habitable floor levels to be equal to or greater than the 100 year ARI flood level plus freeboard.
All floor levels to be equal to or greater than the PMF level plus freeboard.
Floor levels to be equal to or greater than the 100 year ARI flood level plus freeboard. Where this is not practical due to compatibility with the height of adjacent buildings, or
compatibility with the floor level of existing buildings, or the need for access for persons with disabilities, a lower floor level may be considered. In these circumstances, the
floor level is to be as high as practical, and, when undertaking alterations or additions, no lower than the existing floor level.
A restriction is to be placed on the title of the land, pursuant to S.88B of the Conveyancing Act, where the lowest habitable floor area is elevated more than 1.5m above
finished ground level, confirming that the subfloor space is not to be enclosed.
Building Components & Method
1
2
All structures to have flood compatible building components below the 100 year ARI flood level plus freeboard.
All structures to have flood compatible building components below the PMF.
Structural Soundness
1
Engineers report to certify that the structure can withstand the forces of floodwater, debris and buoyancy up to and including a 100 year ARI flood plus freeboard.
2
Engineers report to certify that the structure can withstand the forces of floodwater, debris and buoyancy up to and including a PMF level.
Flood Affectation
1
2
Engineers report required to certify that the development will not increase flood affectation elsewhere, having regard to: (I) loss of flood storage; (ii) changes in flood levels,
flows and velocities caused by alterations to flood flows; and (iii) the cumulative impact of multiple potential developments in the vicinity.
The impact of the development on flooding elsewhere to be considered having regard to the three factors listed in consideration 1 above.
Car Parking and Driveway Access
1
2
3
4
5
6
7
The minimum surface level of open spaces or carports shall be as high as practical, but no lower than 0.1m below the 100 year ARI flood level. In the case of garages, the
minimum surface level shall be as high as practical, but no lower than the 100 year ARI flood level.
The minimum surface level of open parking spaces or carports shall be as high as practical, but no lower than 0.3m above the 20 year ARI flood level.
Garages capable of accommodating more than 3 motor vehicles on land zones for urban purposes, or enclosed car parking, must be protected from inundation by floods
equal to or greater than the 100 year ARI flood. Ramp levels to be no lower than 0.5m above the 100 year ARI flood level.
The driveway providing access between the road and parking spaces shall be as high as practical and generally rising in the egress direction.
The level of the driveway providing access between the road and parking spaces shall be no lower than 0.2m below the 100 year ARI flood level.
Enclosed car parking and car parking areas accommodating more than 3 vehicles, with a floor below the 100 year ARI flood level, shall have adequate warning systems,
signage, exits and evacuation routes.
Restraints or vehicle barriers to be provided to prevent floating vehicles leaving a site during a 100 year ARI flood.
Evacuation
1
2
3
4
5
6
Reliable access for pedestrians required during a 20 year ARI peak flood.
Reliable access for pedestrians and vehicles required to a publicly accessible location during the PMF peak flood.
Reliable access for pedestrians and vehicles is required from the site to an area of refuge above the PMF level, either on site (eg. second storey) or off site.
Applicant to demonstrate the development is consistent with any relevant flood evacuation strategy or similar plan.
Applicant to demonstrate that evacuation in accordance with the requirements of this DCP is available for the potential development resulting from the subdivision.
Adequate flood warning is available to allow safe and orderly evacuation without increased reliance upon SES or other authorised emergency services personnel.
Management and Design
1
2
3
4
Applicant to demonstrate that potential development as a consequence of a subdivision proposal can be undertaken in accordance with this the relevant FRMS and FRMP
Site Emergency Response Flood plan required where the site is affected by the 100 year ARI flood level, (except for single dwelling-houses).
Applicant to demonstrate that area is available to store goods above the 100 year flood level plus freeboard.
No storage of materials below the 100 year ARI flood level.
Notes
i. Freeboard equals an additional height of 500mm.
ii. The relevant environmental planning instruments (generally the Local Environmental Plan) identify development permissible with consent in various zones in the LGA. Notwithstanding,
constraints specific to individual sites may preclude Council granting consent for certain forms of development on all or part of a site. The above matrix identifies where flood risks are likely to
determine where certain development types will be considered "unsuitable" due to flood related risks.
iii. Filling of the site, where acceptable to Council, may change the FRP considered to determine the controls applied in the circumstances of individual applications.
iv. Any fencing that forms part of a proposed development is subject to the relevant Flood Effects and Structural Soundness planning considerations of the applicable land use category.
v. Development within the floodplain may be subject to the Foreshore Building Line objectives of the LEP and REP
vi. Terms in italics are defined in the glossary of this policy. Development types are specified in each land use category. These development types are generally as defined within Environmental
Planning Instruments applying to the local government area.
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9 VOLUNTARY
HOUSE
PURCHASE
VOLUNTARY HOUSE RAISING
&
Property Modification Measures known as Voluntary House Purchase (VHP)
or Voluntary House Raising (VHR) are options which can be considered in a
Floodplain Risk Management Plan in some situations. VHP can be very
expensive and so it is only used infrequently for severely flooded properties.
Council has a VHP program in place for severely flooded houses throughout
the LGA. This is generally reliant upon state and federal funding due to the
expense of such purchases.
In applying NSW Government procedures to VHP, Council ignores the impact
of development constraints and controls associated with the flood hazard, but
has regard to the socially recognised flood history.
A set of criteria that can be used for assessment of the suitability of houses
for VHR is as follows:









The houses have weatherboard, metal or fibrous cement exterior (i.e. a
flexible cladding, double brick or brick veneer houses are very
expensive to raise)
The areas is not planned to be redeveloped or rezoned
Flooding above the floor occurs quite often (e.g. during a 20 year ARI
event)
There are no plans for any other form of flood mitigation
Owners are in favour of house raising and may be willing to contribute
to the raising
The depth of flooding is such that the house raising would be not more
than 2.4 metres above ground and the floor level is above the Flood
Planning Level
The site or area is zoned for single house development (commercial
and industrial areas are generally not suitable)
In some cases, there will be a need to ensure that there is sufficient
waterway area at ground level, so in-filling may not be permitted
The potential benefits of house raising, particularly if the house is
subject to frequent over-floor flooding.
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10 GRATUITY FOR RELOCATION EXPENSES
ASSOCIATED WITH VOLUNTARY HOUSE
PURCHASE
The costs of home relocation are not covered by the Australian and NSW
Governments in their provision of grant funding for VHP. The costs are
generally borne by the vendors of the property. Council will consider a
gratuity of up to $5,000.00 towards the relocation expenses associated with
VHP under the following conditions:
1.
The house is purchased by Council under its VHP scheme associated
with flood prone land and identified in the relevant Flood Risk
Management Plan.
2.
The vendors are residents within the Parramatta LGA and are listed as
the owners of the subject land parcel on Council’s rates notice.
3.
The VHP is subject to grant funding from the NSW and/or Australian
Governments.
4.
Suitable proof of relocation expenses is furnished to Council, i.e.
original or certified copies of paid invoices that clearly identify and
describe the relocation expenses.
5.
Claims will be limited to conveyancing and removalist costs only.
Stamp duty and other fees will not be reimbursed.
11 WHAT DO THE TERMS IN THIS POLICY
MEAN?
For the purpose of this Policy, the following definitions have been adopted:
Adequate Warning Systems, Signage and Exits is where the following is
provided:
(a)
an audible and visual alarm system which alerts occupants to the need
to evacuate, sufficiently prior to likely inundation to allow for the safe
evacuation of pedestrians and vehicles;
(b)
signage to identify the appropriate procedure and route to evacuate;
and
(c)
exits which are located such that pedestrians evacuating any location
during any flood do not have to travel through deeper water to reach a
place of refuge above the 100 year flood away from the enclosed car
parking.
Australian Height Datum (AHD) is a common national plain of level
corresponding approximately to mean sea level.
Average Recurrence Interval (ARI) means the long-term average number of
years between the occurrences of a flood as big as or larger than, the
selected event. For example, floods with a discharge as great as, or greater
than, the 20 year ARI flood event will occur on average once every 20 years.
ARI is another way of expressing the likelihood of occurrence of a flood event.
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Buffer means that part of the development site that is a transition area
between the bushland and the building
Catchment is the entire area of land drained by a river and its tributaries
bounded by a defined ridge line
Consent Authority is the council, government agency or person having the
function to determine a development application for land use under the
Environmental Planning and Assessment Act (EP&A Act).
Concessional Development see Table 2: Land Use Category Definitions
Design floor level or ground level means the minimum floor level that
applies to the development. If the development is concessional, this level is
determined based on what land use category would apply if it was not
categorised as Concessional Development. The floor level standards
specified for the relevant land use category (excluding Concessional
Development) in the low flood risk precinct are to be applied.
Development is defined in Part 4 of the Environmental Planning and
Assessment Act (EP&A Act).
Infill development refers to development of vacant blocks of land that
are generally surrounded by developed properties and is permissible
under the current zoning of the land. Conditions such as minimum floor
levels may be imposed on infill development
New development refers to development of a completely different
nature to that of the former land use. For example, the urban
subdivision of an area previously used for industrial purposes. New
developments involve rezoning and typically require major extensions
of existing urban services, such as roads, water supply, sewerage and
electric power.
Redevelopment refers to rebuilding in an area. For example, as urban
areas age, it may become necessary to demolish and reconstruct
buildings on a relative large scale. Redevelopment generally does not
require either rezoning or major extensions to urban services.
Ecologically Sustainable Development (ESD) is using, conserving and
enhancing natural resources so that ecological processes, on which life
depends, are maintained, and the total quality of life, now and in the future,
can be maintained or increased. A more detailed definition is included in the
Local Government Act 1993.
Effective warning time is the time available after receiving advice of an
impending flood and before the flood waters prevent appropriate flood
response actions being undertaken. The effective warning time is typically
used to move farm equipment, move stock, raise furniture, evacuate people
and transport their possessions.
Enclosed car parking means car parking areas which are potentially subject
to rapid inundation, which consequently increases risk to human life and
property (such as basement of bounded car parking areas). The following
criteria apply for the purpose of determining what enclosed car parking is:
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(a)
(b)
flooding of surrounding areas may raise water levels above the
perimeter which encloses the car park (normally the entrance),
resulting in rapid inundation of the car park to depths greater than 0.8m
and
Drainage of accumulated water in the car park has an outflow
discharge capacity significantly less than the potential inflow capacity.
Extreme flood means an estimate of the probable maximum flood, which is
the largest flood likely to ever occur.
Flood is a relatively high stream flow which overtops the natural or artificial
banks in any part of a stream, river, estuary, lake or dam, and/or local over
land flooding associated with major drainage as defined by the FDM before
entering the water course.
Flood compatible building components means a combination of measures
incorporated in the design and/or construction and alteration of individual
buildings or structures subject to flooding, and the use of flood compatible
materials for the reduction or elimination of flood damage.
Flood compatible materials include those materials used in building which
are resistant to damage when inundated.
Flood education, awareness and readiness:
Flood education seeks to provide information to raise awareness of
the flood problem so as to enable individuals to understand how to
manage themselves and their property in response to flood warnings
and in a flood event. It invokes a state of flood readiness.
Flood awareness is an appreciation of the likely effects of flooding and
knowledge of the relevant flood warning time.
Flood readiness is an ability to react within the effective warning time.
Flood evacuation strategy means the propose strategy for the evacuation of
areas within effective warning time during periods of flood as specified within
and policy of Council, the FRMP, the relevant SES Flood Plan, by advices
received from the State Emergency Services (SES) or as determined in the
assessment of individual proposals.
Flood prone land (being synonymous with flood liable and floodplain) is
the area of land which is subject to inundation by floods up to and including an
extreme flood such as a probable maximum flood (PMF).
Flood risk is the potential danger to personal safety and potential damage to
property resulting from flooding. The degree of risk varies with circumstances
across the full range floods. Flood risk in the Floodplain Management Manual
is divided into 3 types, existing, future and continuing risks. They are
described below
Existing flood risk is the risk a community is exposed to as a result of
its location on the floodplain.
Future flood risk is the risk the community is exposed to as a result of
new development on the floodplain
Continuing flood risk is the risk a community is exposed to after
floodplain management measures have been implemented.
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Flood storage is those parts of the floodplain that are important for the
temporary storage of floodwaters during the passage of a flood. The extent
and behaviour of flood storage areas may change with flood severity, and loss
of flood storage can increase the severity of flood impacts by reducing the
natural flood attenuation.
Floodplain Development Manual (FDM) refers to the document dated April
2005, published by the New South Wales Government and entitled
“Floodplain Development Manual: the management of flood liable land”.
Floodplain Risk Management Plan (FRMP) means a plan prepared for one
or more floodplains in accordance with the requirements of the FDM or its
predecessor.
Floodplain Risk Management Study (FRMS) means a study prepared for
one or more floodplains in accordance with the requirements of the FDM or its
predecessor.
Floodway is those areas of the floodplain where a significant discharge of
water occurs during floods. They are often aligned with naturally defined
channels. Floodway’s are areas that, even if only partially blocked, would
cause a significant redistribution of flood flow, or significant increase in flood
levels.
Freeboard is a factor of safety expressed as the height above the flood used
to determine the design floor level or ground level. Freeboard provides a
factor of safety to compensate for uncertainties in the estimation of flood
levels across the floodplain, such as wave action, localised hydraulic
behaviour and impacts that are specific event related, such as levee and
embankment settlement, and other effects such as “greenhouse” and climate
change.
Habitable floor area means:

in a residential situation: a living or working area, such as a lounge
room, dining room, rumpus room, kitchen, bedroom or workroom;

In an industrial or commercial situation: an area used for offices or
to store valuable possessions susceptible to flood damage in the event
of a flood.
Hazard is a source of potential harm or a situation with a potential to cause
loss. In relation to this manual, the hazard is flooding which has the potential
to cause harm or loss to the community.
Hydraulics is the term given to the study of water flow in waterways; in
particular, the evaluation of flow parameters such as water level and velocity.
Hydraulic hazard is the hazard as determined by the provisional criteria
outline in the FDM in a 100 year flood event.
Local overland flooding means inundation by local stormwater runoff rather
than overbank discharge from a stream, river, estuary, lake or dam.
Merit approach is an approach, the principles of which are embodied in the
FDM which weighs social, economic, ecological and cultural impacts of land
use options for different flood prone areas together with flood damage, hazard
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and behaviour implications, and environmental protection and well being of
the State’s waterways and floodplains.
Outbuilding means a building which is ancillary to a principal residential
building and includes sheds, garages, car ports and similar buildings.
Probable maximum flood (PMF) is the largest flood that could conceivably
occur at a particular location, usually estimated from probable maximum
precipitation (rainfall).
Reliable access during a flood means the ability for people to safely
evacuate an area subject to imminent flooding, having regard to the depth and
velocity of flood waters, the suitability of the evacuation route, and without a
need to travel through areas where water depths increase.
Risk means the chance of something happening that will have an impact. It is
measured in terms of consequences and probability (likelihood). In the context
of this plan, it is the likelihood of consequences arising from the interaction of
floods, communities and the environment.
Site Emergency Response Flood Plan is a management plan prepared in
consultation with the State Emergency Services (SES) and approved by
Council which demonstrates the means to minimise the likelihood of flood
damage, including demonstrated ability to move goods above flood level
within the likely available flood warning time and a requirement for flood drills
for larger commercial/industrial premises. This could be in the form of an
individual Flood Plan.
Subfloor Space is the space between the underside of a suspended floor
and the ground.
Survey plan is a plan prepared by a registered surveyor which shows the
information required for the assessment of an application in accordance with
the provisions of this Policy based on AHD.
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