02.07.2021 Views

North Wagga Submission for BMT Group Peer Review

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

Submission presented on behalf of the North Wagga Wagga

Residents’ Association (NWWRA) to BMT Group for

consideration in the Peer Review of the 2009 and 2018 FRMPs.

Author:

Contributors:

Fiona Ziff, Treasurer of the NWWRA.

Dr Jenny Woods

Professor Michael Friend

Fiona Ziff

Dated: 10 March 2021

Page 1 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

Contents

Executive Summary .................................................................................................................................... 3

Background ................................................................................................................................................. 5

Timeline of Flood Risk Mitigation Process .................................................................................................. 6

Discussion of issues arising. ........................................................................................................................ 9

(1) Critical information pertaining to the unsustainable emotional and financial trauma endured by

Residents as a direct result of flooding and inadequate protection, is omitted from the 2018 FRMP.. 9

(2) Critical feedback from all prior community consultation conducted in the aftermath of the

catastrophic 2012 flood, all favouring a 1 in 100 levee for North Wagga, is omitted and in its place

targeted feedback that has been specifically cherry-picked to skew it towards a foregone conclusion

contradicting Residents’ express needs. ..............................................................................................10

(3) Critical information presented in all preceding flood reports, that favour a 1 in 100 levee for

North Wagga, is omitted and contradicts arguments used in the 2009 FRMP to support the

recommendation of a 1 in 100 levee upgrade for Central/CBD. ..........................................................15

(4) The cumulative effects on flood levels from the thickened vegetation and the Main City Levee

upgrade, which expose North Wagga to the increased risk of a Council-made flood, are not

considered in the 2018 FRMP. ..............................................................................................................20

(5) The 2018 FRMP lacks assessment of intermediate Levee options. ................................................21

(6) The 2018 FRMP relies on a weak Matrix scoring system. ...............................................................22

References ....................................................................................................................................................25

Page 2 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

Executive Summary

The 2018 Floodplain Risk Management Plan (FRMP) recommends further investigation of a 1 in 20 levee

and the Voluntary House Raising (VHR) and Voluntary House Purchase (VP) Scheme as flood risk mitigation

options for North Wagga. It also recommends that a 1 in 100 levee not be pursued any further for the

following main reasons:

a) the upstream impact is unacceptable.

b) North Wagga Residents would have a false sense of security and become complacent about flood

risk, increasing the risk that people would not evacuate on time in a flood event, exacerbated by

the low flood island issue.

c) it may not be aesthetically pleasing.

d) it may impact private and public land and it may need to be completely replaced, impacting

construction practicality and cost estimates.

e) it may lead to increased development behind the levee.

f) flood water may get trapped behind the levee causing a swamp.

Following the catastrophic 2012 flood, Council promised to investigate a 1 in 100-year protection levee for

North Wagga. A mandatory community consultation was conducted by Council in March 2015, followed

by an on-line survey in May 2015. Both resulted in majority support for a 1 in 100 levee, the results of

which were omitted from the 2018 FRMP. WMAwater’s 2014 Flood Model Revision Report; the Public

Work’s 2015 North Wagga Wagga Levee Options and Third Party Impacts Report; and the Council’s 2015

PSRP-7 Levee Upgrade Detailed Design & Community Consultation Report were also undertaken, which

collectively conclude that a 1 in 100 levee for North Wagga is the most favourable solution for North Wagga

because it has - majority support from the community; minimal upstream impact; significantly reduces

Annual Average Damages to justify cost; and overall substantially benefits flood mitigation in the Wagga

Floodplain. The conclusions reached in the 2018 FRPMP contradict these reports.

Council have made their position on North Wagga publicly clear over the years, that is, they cannot justify

spending money in North Wagga and it shouldn’t be expected because Residents bought In North Wagga

knowing it is in a floodplain with limited protection. It appears that because the various flood studies and

community consultations conducted after the catastrophic 2012 flood did not support their agenda,

Council ultimately steered the most recent flood study and community consultation for the purpose of

skewing information in the 2018 FRPMP. This culminates in the flawed Multi Criteria Assessment Matrix,

which rather than reflect what earlier flood studies recommend and what Wagga’s most vulnerable

floodplain community needs, reflects what Council are willing to provide.

The Floodplain Development Manual informs us that “The Primary objective of the NSW Flood Prone Land

Policy is to reduce 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

Page 3 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

methods wherever possible”. It also states the social and economic needs of the community must be

satisfied, and that options be community supported.

Contrary to the Floodplain Guidelines, the 2018 FRMP is in our view flawed for the following reasons:

1) Critical information pertaining to the unsustainable emotional and financial trauma endured

by Residents as a direct result of flooding and inadequate protection, is omitted.

2) Critical feedback from all prior community consultation, conducted in the aftermath of the

catastrophic 2012 flood, all favouring a 1 in 100 levee for North Wagga, is omitted and in its

place targeted feedback that has been specifically cherry-picked to skew it towards a foregone

conclusion.

3) Critical information presented in all preceding flood reports that favour a 1 in 100 levee as the

best option for North Wagga is omitted, and it contradicts arguments used in the 2009 FRPMP

to support the recommendation of a 1 in 100 levee upgrade for Central/CBD.

4) The cumulative effects on flood levels of the thickened vegetation and the Main City Levee

upgrade, which expose North Wagga to the increased risk of a Council-made flood, are not

considered in the 2018 FRMP.

5) Lacks assessment of intermediate Levee options.

6) Relies on a weak Multi-Criteria Assessment Matrix.

With clear direction from a Senior Council Staff member during a 2017 committee meeting, that Council

do not wish to spend any money in North Wagga, the committee members confidently signed off on a flood

report which justifies further study of either VHR or VP, or a token levee which will see the inundation of

174 properties in an event slightly higher than a 1 in 20 flood event, increasing to 215 during a 1 in 100

flood event equating to an Average Annual Damages bill of approx. $1,583,000.

North Wagga Residents (the Residents) are facing a heightened risk of flood which will be largely Councilmade,

and proper protection in the form of a 1 in 100 levee is required as a matter of urgency. To deny

North Wagga, in the way Council has done and continues to do, is not incompetence, it is in our view

negligence. It is emotionally and financially the right thing to do to relieve Residents of the unsustainable

emotional and financial trauma attributable to regular flooding. The current situation is not justifiable,

particularly in light of the fact that Federal and State provide technical and financial support to avoid it

wherever possible, nor is it ethical.

The Association trusts that the Peer Review will highlight the flaws in the current flood plan and

recommend that in accordance with previous studies, community consultations, reports and the State

Policy Guidelines, Council should make arrangements to implement the 1 in 100 levee in North Wagga

without further delay to avoid another catastrophe and the legal consequences that may eventuate.

Page 4 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

Background

The North Wagga Wagga village (“North Wagga”) comprises approximately 203 households and a

population of approximately 600 people.

It is arguably Wagga’s first settlement. Wagga’s first hospital was built in North Wagga. Prior to the 1960’s,

people bought in North Wagga because compared to Central, North Wagga posed the least flood threat in

the floodplain, sitting on land that is mostly higher than the original parts of the CBD. The village mostly

suffered what the older residents call “minor and very manageable flooding” that saw most residents

remain in their homes during an average flood event.

According to Council’s engineers WMAwater, North Wagga is Wagga’s “high risk” community, protected

by a 1 in 8 levee (a 12% AEP levee). It was originally constructed in the 1990’s as a 1 in 20 levee.

The only reason why North Wagga secured the 1 in 20 levee was because Mr. Albert Bergman, a Resident,

lobbied decision makers for approx. 20 years and they finally relented. So convinced were the decisionmakers

that North Wagga should disappear, the 1985 Development Control Plan excluded the village of

North Wagga. It was destined to rot but with Mr. Bergman’s assistance, the Residents resisted, and a sign

was erected which is still in place today stating, “We Shall Not Be Moved”.

Wagga’s “Low Risk” community in Central Wagga, has been protected by a levee originally constructed in

the 1960’s, which has been upgraded over time with the most recent upgrade being in 2019 to a 1 in 100

levee (1% AEP Levee).

Since the Main City Levee was constructed in the 1960s, it has successfully diverted flood waters away from

Central Wagga and the CBD, leaving it flood free for over 57 years. These flood waters however have been

pushed up and over the token and temporary North Wagga levee, causing catastrophic flooding in 1974.

The supposed 1 in 20 levee was finalized in 1990 but was overtopped in 2012, required an evacuation in

2010, and a ‘high alert’ in 2016.

North Wagga was, and continues to be, sacrificed to save Central/CBD. Residents do not accept this

situation and the North Wagga Wagga Residents’ Association (the Association) represents most of the

North Wagga residents (“Residents”) who rightfully seek protection in the form of a 1 in 100 levee, the

same level of protection afforded to Central/CBD.

Page 5 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

Timeline of Flood Risk Mitigation Process

2002 In an act viewed by the Association as negligence, Council planted thousands of trees and

shrubs close to the pinch point in the floodplain, a Reserve of approx. 37 ha located

between the North Wagga village and the Murrumbidgee River known as “the flats”.

May 2009

The Reserve is currently protected by biodiversity legislation and has been left to thicken.

The 2009 FRMP was finalised, recommending further study into the feasibility of

upgrading the Main City Levee to a 1 in 100 for Central/CBD, and for North Wagga,

consideration be given to maintaining the existing 1 in 20 levee, and allow house raising

for suitable houses.

The Main City Levee was Council’s focus in the report, which acknowledges a vegetation

issue in North Wagga and proposes a Vegetation Management Study at the Parken

Pregan Lagoon and surrounding Reserve.

2010 to

2014

Flood modelling tools were updated and applied to the flood data and the 2012 flood was

studied. The reduction in river conveyance, evidenced by studies of the 2012 flood, led

to the downgrade of the North Wagga levee from a 1 in 20 to a 1 in 8 levee.

WMAwater confirm that the most significant contributor to this downgrade was the thick

vegetation in the North Wagga flats, increasing flood levels by some 200mm to 300mm.

March 2012

North Wagga suffered a catastrophic flood.

Council offered to look at the 1 in 100 levee option when their offer to upgrade the levee

back to the 1 in 20 level was rejected by most residents.

May 2013

Feb &

March 2014

16th May

2014

2013 Public Works commenced investigations into the economic feasibility of North

Wagga levee options and third-party impacts.

Two drafts of WMAwater’s 2014 Flood Model Revision Report favouring a 1 in 100 levee

upgrade for North Wagga were issued.

Councillor Conkey states at a Community4Wagga meeting held at the International Hotel,

that he cannot justify spending any money in North Wagga.

Page 6 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

21 May

2014

While WMAWater’s Draft 2014 Flood Model Revision Report was on public display, the

author Stephen Gray presents findings to the North Wagga residents at the North Wagga

Hall.

Mr. Gray reiterated that a 1 in 100 levee in North Wagga would have minimal impact

upstream and that it was a feasible solution for North Wagga. Residents were confident

they would secure the same protection as Central/CBD.

August

2014

March 2015

May 2015

The 2014 Flood Model Revision Report is finalised, confirming that the upstream effects

of a 1 in 100 North Wagga levee are insignificant and in fact do not differ significantly

from when only the Main City Levee is in place. It also confirms that the upstream area

is “sparsely populated” with “few properties”, deeming the overall upstream effects

small.

Council initiates community engagement meetings to discuss flood mitigation options for

the Wagga floodplain. The feedback collected at the community meetings and

afterwards demonstrates strong support for an upgrade of the Main City Levee and the

North Wagga levee to a 1 in 100-year levee.

Council initiates an on-line survey about levee options for North Wagga because they are

of the opinion that the open meetings prevented residents from speaking up against the

majority who want a 1 in 100 levee.

23 rd May NWWRA completed a door knock of the entire community to facilitate

residents’ confidential responses to the council survey. This survey resulted in majority

support for a 1 in 100 levee (75%).

13 July 2015 Council Report PSRP-7 is presented to Council’s Policy & Strategy meeting. It contains

the results of the community consultations and the 2015 Public Works economic report

on levee options and third-party impacts. It concludes that “on the basis of the economic

appraisal and community consultation, it is recommended that Council upgrade the

North Wagga levee system to provide a 1 in 100-year level of protection”.

20 May

2016

Aug/Sept

2016

Feb 2017

The Special Rate Variation is approved to partly fund the $23.3M upgrade of the city’s

flood levee system, including the North Wagga levee upgrade. The then Mayor Kendall

advised the public that the project would provide the city with a 1 in 100-year level of

protection and contrary to all reports conducted to-date, only a 1 in 20-year level of

protection for North Wagga. Ratepayers were also told that the North Wagga portion

would be refunded if the levee did not proceed.

In the lead up to the drafting of the 2018 FRMP, Council conducts “Initial Community

Consultation” concerning flood risk mitigation in the Wagga Floodplain. The feedback is

collated and detailed in Annexure B of the 2018 FRMP. The North Wagga Residents are

excluded.

Council’s Director of Infrastructure and Planning, Caroline Angel announces at the

Floodplain Committee meeting that Council does not wish to spend any money in North

Wagga. Erin Askew of WMAwater denies the existence of 2014 Flood Modelling Revision

(that favours a 1 in 100 levee) and confirms that the author Stephen Gray no longer works

for WMAwater.

Page 7 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

Oct 2017

Apr 2018

21 Dec

2018

25th Jan

2020

The draft 2018 FRMP goes on public exhibition. The Wagga community is invited to make

submissions, summarized in Annexures M. The feedback favours the Voluntary Scheme

which residents have categorically rejected since 2012.

2018 FRMP is finalised. It recommends the 1 in 20 levee and Voluntary Scheme be

investigated further, the two options which got least support from Residents in two

community consultations. It also recommends the 1 in 100 levee option not be pursued

any further.

Mayor Conkey is interviewed on Prime 7 about the celebration of the commencement of

Stage 2 of the Main City Levee Upgrade. A journalist asks him about North Wagga. Mayor

Conkey replies “unfortunately the people of North Wagga live on a floodplain and when

they bought their properties, they realised it was on a floodplain and it had limited

protection over there”. Residents believe his comments potentially sway public opinion

(and potential community feedback) about flood protection for North Wagga.

In a letter from the Association to the Floodplain Committee, dated 25th January 2020

the Association asks for specific information which seemed to be lacking in the arguments

used against a 1 in 100 Levee for North Wagga, as well as further clarification of

information which seemed to contradict earlier reports.

17 March

2020

A motion is moved by J Rolfe and R Kendall at the FRMAC meeting for the Committee to

recommend that a third party be engaged to undertake a short review of options for

North Wagga in the 2018 FRPMP to be considered for inclusion in the current feasibility

study.

2 June 2020 The Minutes of the Floodplain Risk Management Advisory Committee dated 2 June 2020

include a motion carried by P Murray and R Kendall that the Committee “……specifically

acknowledge that questions raised in the January 2020 letter were a catalyst for the

planned Peer Review”.

It appears the Floodplain Committee was either unwilling or unable to explain the

justifications for the recommendations made in the 2018 FRMP.

Page 8 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

The Association presents the following detailed report for consideration in the Peer Review

of the 2009 and 2018 FRMPs.

Discussion of issues arising.

(1) Critical information pertaining to the unsustainable emotional and

financial trauma endured by Residents as a direct result of flooding and

inadequate protection, is omitted from the 2018 FRMP.

The Floodplain Development Manual clearly states that the Policy outcomes are concerned with “the

management of the consequences of flooding as they relate to the human occupation of the floodplain, in

full recognition that the social and economic needs of the community, as well as being compatible with the

maintenance or enhancement of the natural ecosystems, must be satisfied”. In Appendix G7.1.1 it states

“to objectively compare issues and management measures, it is necessary to gather a variety of socioeconomic

data” and goes on to suggest that a Community Impact Study might be necessary. It also states

that “whilst direct economic analysis is important it is not unusual to proceed with urban flood mitigation

schemes on largely social grounds, that is, on the basis of the reduction in intangible costs and social and

community disruption. The 2018 FRPMP does not consider the social and economic needs of Residents

and is therefore, in our view, unsound.

Residents are faced with the constant threat of flooding because the levee is not adequate. Residents are

also incredibly nervous about the increased risk brought about by the thickened vegetation and the recent

upgrade of the Main City Levee which only exacerbates the situation. Residents’ lives revolve around the

likelihood of a flood. Food protection premiums are exorbitant. If residents can afford them, it places

significant financial strain on the household finances. Most residents cannot afford them, so live with the

stress of having no certainty about the capacity to pay for flood damage repairs. Every time there is a

forecast of above average rain, residents start monitoring upstream rainfall forecasts, dam levels and river

levels. If a flood warning is issued, most residents face the real risk of losing their belongings because they

are not able to elevate them or relocate them. They also have only hours to relocate their family and

animals as well as find a temporary home to relocate to. If the village floods, Residents are faced with the

cost of repairs; being displaced for up to eighteen months; increased flood premiums; and loss of property

value.

The matter of the social and economic cost of flooding is addressed in our representative Dr Jenny Woods’

Thesis for the Degree of a Doctor of Philosophy entitled “Experiences of community spirit in flood recovery:

Exploring the opportunities for community development” dated March 2017. While on the Committee, Dr

Woods attempted to convince committee members that her research revealed serious stress-related

health issues among residents, such as PSTD, high blood pressure, anxiety, MS. She also pointed out that

some residents are not flood protected because the insurance premiums are exorbitant and money has to

be found to repair flood damage, exacerbating the emotional trauma. Dr Woods referred to the

quantifiable economic costs incurred by residents with regard to cost of repairs and loss of house value.

However, Dr Woods was consistently met with strong resistance from Council staff, Councillors and certain

Page 9 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

Committee members who would deflect to the matter of complacency about evacuation. Finally, Dr

Woods was advised by the then representative of Wagga’s Office of Environment and Heritage, that her

role on the Committee was merely to convince the community to accept the report.

The economic needs of the North Wagga community are tangible, quantifiable and effect approximately

221 households, however Council has never sought this information and consequently it is not considered

in the 2018 FRPMP. The 2009 FRPMP also omits this information. The matter of “Intangible Flood

Damages” is raised in Section 7.2 of the 2018 FRMP, however it merely describes the types of intangible

flood damages, such as the social impacts, explaining that they are too hard to quantify and so contrary to

the 2005 Policy, they are not considered. Council never sought this information either. The Multi-Criteria

Assessment, designed for the purpose of assessing intangibles such as the social impacts of flooding on

Residents, also omits this critical information. The legitimacy of the conclusions reached and

recommendations made in the 2018 FRMP is therefore called into question.

While the 1 in 100 Main City Levee will not prevent ‘the big one’ from happening and eventually the entire

Wagga floodplain will be inundated, occupants of Central/CBD have enjoyed a flood free period for over

57 years due to adequate protection. This affords them a level of comfort, enabling them to get on with

their day to day lives, to plan for the future and not be constantly worrying about whether they will flood

or not. Life on the other side of the river is starkly different.

Had the social and economic needs of the community been considered, as intended by the State Policy

Guidelines, the benefit of alleviating the unsustainable emotional and financial trauma with proper

protection in the form of a 1 in 100 levee would be clear and would far outweigh the arguments used

against it, regardless of their legitimacy. To have 174 properties inundated in an event slightly higher than

a 1 in 20-year flood, which increases to 215 in a 1 in 100-year flood event is not ethical when it can so easily

be avoided.

(2) Critical feedback from all prior community consultation conducted

in the aftermath of the catastrophic 2012 flood, all favouring a 1 in 100

levee for North Wagga, is omitted and in its place targeted feedback

that has been specifically cherry-picked to skew it towards a foregone

conclusion contradicting Residents’ express needs.

The 1 in 20 levee and the VHR and VP Scheme, as possible flood risk mitigation options for North Wagga

have been presented to the community since the 2012 catastrophic flood and have been categorically

rejected for sound reasons. So how is it that these options are now the recommended solutions for North

Wagga?

Following the 2012 flood, residents pleaded with Council for a higher levee and they committed to

investigating a 1 in 100 levee option for North Wagga. As part of this process, feedback was gathered and

documented during official community engagement meetings held in March 2015. The results, detailed in

the 2015 Council PSRP-7 Report, demonstrate majority support for a 1 in 100 levee for North Wagga and

minimal support for the 1 in 20 levee (9%) and Voluntary Scheme (0.8%). This information was presented

Page 10 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

to the then Mayor Kendall at the Policy & Strategy meeting on 15 th July 2015. We understand Mayor

Kendall was a member of the Floodplain Committee at the time and that this information was not

presented to the Committee for consideration.

The reasons for the rejection of the VHR & VP Scheme and 1 in 20 levee, of which Council are fully aware,

are as follows -

(a) The 1 in 20 levee is not high enough and trauma brought about by the threat of regular flooding is not

relieved; (b) many elderly people cannot negotiate stairs if their house was to be raised, and don’t wish to

relocate because they have been living in the village their entire lives and it would be too traumatic; (c) the

majority of people do not have the necessary funds to contribute to house raising. We understand Lismore

residents were required to outlay the entire amount and apply to Federal and State governments for

reimbursement; (d) Many of the houses are brick and cannot be raised; and (e) many younger families are

fifth generation in the village and do not wish to be relocated.

At the time WMAwater’s 2014 Flood Model Revision report was on public exhibition, our resident Mr.

Laurie Blowes heard Councillor Conkey advising attendees at a public Community4Wagga meeting at the

International Hotel on 16th May 2014, that “he cannot justify spending any money in North Wagga”. Two

drafts of WMAwater’s Flood Model Revision Report had already been issued by this time, in February 2014

and March 2014 respectively, clearly favouring a 1 in 100 levee upgrade for North Wagga. Around the same

time the author of the report Stephen Gray met with Residents to discuss the findings. It was understood

that a 1 in 100 levee in North Wagga was the most favourable solution because the effects of it were not

significantly more than what the 1 in 100 Main City Levee already has upstream on only a handful of

sparsely located properties. Councillor Conkey’s comments suggest however that rather than act in

accordance with State Policy and expert advice, designed to protect Residents like us, Council were intent

on acting in accordance with their own agenda to spend as little, if anything on North Wagga.

In May 2015, Council initiates an on-line survey about levee options for North Wagga. At the time, our

representative Dr Jenny Woods was advised by Council that the open meetings held earlier, prevented

residents from speaking up against the majority who supported a 1 in 100 North Wagga levee and a

different format is required. The results of the on-line survey were compiled by then Council staff member

Lauren Pezet, who confirmed with our representative Dr Jenny Woods that 75% support was given for a 1

in 100 levee.

Under normal circumstances, that is, if Council were genuine about their investigations of adequate flood

protection for North Wagga, the consistency between the two community consultations would allay

concerns around the validity of the engagement process. However, the results of both surveys were

omitted from the 2018 FRMP, leading Residents to believe that because they did not reflect the conclusion

Council was seeking, they were discarded.

In May 2016 the Special Rates Variation was implemented by Council to raise its third share of funds for

the levee upgrade project. By this stage the two official community engagements sessions resulting in

majority support for a 1 in 100 levee for North Wagga had taken place; the 2014 WMA Report favouring

the 1 in 100 levee for North Wagga had been finalised; and Council’s Report PRSP-7, recommending a 1 in

100 levee for North Wagga as “socially and economically favourable” had been presented to Council.

However, the total funds to be collected over a five-year period only included the cost of a 1 in 20 levee

Page 11 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

for North Wagga. The ratepayers were also advised that if the North Wagga levee did not proceed,

ratepayers would be refunded. At this point in time, Council appeared to be giving the clear indication to

residents that Council had no intention of implementing the most favourable 1 in 100 levee option.

Predictably, the Floodplain Committee reconvened in 2017 and Council’s Director of Infrastructure and

Planning, Caroline Angel, announced to all those present, that Council did not wish to spend any money in

North Wagga. According to our representative Dr Jenny Woods, it seemed a noticeably clear directive from

Council that it was directing the Floodplain Committee towards a foregone conclusion.

In the 2018 FRMP, WMAwater refers to the latest consultation as the “Initial community consultation”, a

label which effectively denies the existence of all previous community engagement feedback that

demonstrated majority support for a 1 in 100 North Wagga levee. The preceding community meetings and

surveys were widely publicised, and obviously attracted those people most affected by flooding, which

under normal circumstances, would be the very purpose of such consultation. However, following a

comment made by Councillor Kendall, that North Wagga was disproportionately represented, Council

conduct yet another community engagement consultation in August/Sept 2016. It seemed apparent that

Council was grappling with the challenge of getting the feedback that supported their agenda. The only

answer was to completely discard feedback from North Wagga. Annexure B features the summary of the

consultation. Notably, feedback from North Wagga residents is excluded.

The Feedback features comments from Gumly, Oura and Wagga Floodplain Residents’ Protection

Association Inc. It is accepted that Gumly and Oura will not be impacted in any way by a 1 in 100 levee in

North Wagga, however their input about the 1 in 100 levee seemed more important than that of the very

community which would be most benefited by it. Interestingly, the most prominent group to feature in

the Annexure B feedback summary is the Wagga Floodplain Residents’ Protection Association (WFRPA),

comprising a total of 23 comments out of 48. The name Wagga Floodplain Residents’ Protection

Association (WFRPA) implies representation of all floodplain residents and that the survey is

comprehensive. This is misleading.

The WFRPA represents those property owners located in an area upstream of North Wagga, outside the

levee system, which happens to vigorously oppose the 1 in 100 levee for North Wagga. Ironically, Council

Report PSRP-7 confirms there only 18 property owners in this upstream area who will see a “small” impact.

The upstream area is described in the 2014 WMAwater Report as containing “few properties” that are

“sparsely populated” and will not see any extra impact from a 1 in 100 levee in North Wagga than they

already get from the Main City Levee. In comparison, North Wagga has approximately 221 properties, 174

of which suffer catastrophic flooding from flood waters diverted by the Main City Levee in a flood as low

as a 1 in 20. By excluding feedback from North Wagga, the report detracts from the impact of regular

flooding in North Wagga and the clear benefits of mitigating it.

In addition, the respondents appear to be giving feedback on deficient information. Point 25 the Annexure

B summary indicates the WFRPA believes that “members may see increases of up to 0.3m associated with

levee raises (both North Wagga and the CBD). As discussed earlier, this information is misleading. Point

27 indicates that a detailed, case-by-case, investigation of third-party impacts of the 1 in 100 levee in North

Wagga is yet to be conducted. WMAwater confirms it is not in the Scope of Work for the 2018 FRMP. No

decision about upstream impact should be made without knowing what that impact actually is.

Page 12 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

In Point 29 – WFRPA are concerned that “raising the levees could lead to decreases in property value and

increase in capital losses. WMAwater reply “noted as a social impact of assessed levee options in 9.2.1.

and 9.2.3. This might be a reasonable argument if the information they were relying on is accurate but it

is not and there will be no inundation through their homes until there is an event higher than a 1 in 100

flood. This argument is therefore misleading and skews the feedback. Regardless, the upstream properties

are located outside the levee system and they flood regardless of whether North Wagga is protected by a

levee or not. However, the most concerning thing is that nowhere in these two sections does it mention

the impact on property values in North Wagga. By its omission, the capital losses of a handful of properties

which flood anyway and will not see water through their homes, detracts from the fact that during an event

slightly higher than a 1 in 20 flood, 174 properties will see catastrophic, above floor level flooding.

The feedback reflects the false scenarios offered in the 2018 FRMP which are discussed in the body of this

report - Point 36 WFRP expresses concern that “if North Wagga levee is raised, increased development will

likely result behind that levee, which will lead to an increase in AAD. This is also addressed in M3.5 and

raised in Section 9.3 of the 2018 FRMP. If Council had discussed this matter with North Wagga residents,

they would have discovered that most Residents agree that over development of the village, once a 1 in

100 levee is built, is not appropriate. Residents value the open spaces they currently enjoy and they intend

to maintain it. Notwithstanding this, the argument cannot justify the consequences of the inundation of

174 properties in a flood event as low as a 1 in 20-year flood.

The selective feedback also detracts from the clear benefits of protecting North Wagga with a 1 in 100

levee for the Wagga floodplain in general. Outlined in Section 7.1.3.1 of the 2018 FRPMP, Table 28, is the

fact that North Wagga “is the largest contributor to AAD of any of the floodplain villages, and only

contributing slightly less than Wagga CBD despite having 17 times fewer dwellings. This large portion of

the AAD is a result of the more frequently occurring damages in North Wagga”.

In Oct 2017 the draft 2018 FRMP was publicly displayed and feedback submissions sought. Appendix M

records the submissions; however, it lists only a limited number of issues that were addressed in the revised

version. While there will be some duplication, the lack of transparency (not showing all issues raised in

submissions) suggests the submissions have been ‘cherry picked’ as to what is responded to.

For example, North Wagga resident Michael Friend’s submission (135) raised several significant issues, of

which only two were partially addressed in the revised plan. On page 14 of Appendix M, Michael Friend’s

criticism of the VHR proposal was partially addressed – the consultants have taken only the latter half of

the issue raised and ignored the concern around the rigour applied to arriving at the conclusion to progress

a feasibility study.

Similarly, on Page 37, Michael Friend’s concern with the multi-criteria assessment is only partially

addressed – dealing with a couple of specific examples of issues rather than the principle raised of each

criterion having the same weighting – e.g., technical feasibility has the same weighting on the overall

number as economic benefit.

There is also a consistent theme through the document that implies bias towards VHR and VP. Some

specific submissions have been referenced more frequently (e.g., submissions 60 and 139) – interestingly

these submissions strongly support the VHR and VP options and are strongly against any increase in the

Page 13 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

North Wagga Levee. The VP scheme receives the highest score in the multi criteria analysis at +17,

seemingly based on feedback that was cherry picked.

Our representative Dr Jenny Woods recalls at a Floodplain meeting that Councillor Kendall, contrary to all

prior feedback from experts and residents, verbally approved the VHR and VP Scheme option on the basis

that it is an option that Council would not have to fund. It was discussed at the time that the funding would

be a three-way split between Federal and State Governments and Residents. Councillor Kendall queried at

the time whether residents could be forced to do it, indicating that those residents who could not

participate would have to be excluded.

The 2018 FRPMP states a ‘large number’ of responses support VHR, yet this is unquantified. Certainly,

earlier community consultation within North Wagga (summarized in the 2015 Council Report PSRP-7)

showed very little support within the North Wagga for VHR or VP at only 0.8%, and also deemed the option

cost prohibitive. The 2009 FRMP points to the fact that widespread application of the VHR and VP Scheme

would not be supported by North Wagga residents and is not economically sound. The State Policy

Guidelines suggest that VHR & VP is appropriate for remote or isolated properties Responses in support of

the Voluntary Scheme options are therefore likely to be outside of North Wagga, and as indicated above,

submissions 60 and 139 have been regularly referenced to support VHR and VP Scheme. If council pursues

down the path of a feasibility study on this, the outcome will be like previous analyses of this option. The

result will be more money wasted on consultants for an outcome that is already known and the continued

lack of action for North Wagga exposes residents to greater risk of flooding. However, this option scores

the highest at +17 on the matrix.

On 21 December 2018, Prime 7 covered the celebration of the commencement of Stage 2 of the Main City

Levee upgrade. While standing on the Main City Levee, Prime 7 journalist asked Mayor Conkey about

protection for Wagga’s most vulnerable community, North Wagga. Mayor Conkey replied “unfortunately

the people of North Wagga live on a floodplain and when they bought those properties, they realised it

was on a floodplain and it had limited protection over there”. Again, a clear indication is given by Council

that it has no intention of adequately protecting North Wagga in the same way that Central/CBD is

protected, despite all official evidence pointing to the benefits of doing so. This public announcement

could also be an attempt to influence public opinion, upon which Council could rely in the future.

It is important to note here that WMAwater have conducted all official flood studies on behalf of Council

since the 2005 Flood Prone Land Policy was implemented and it is a valuable contract. As far as we are

aware, the studies and reports have not been subject to a peer review. Recommendations from

WMAwater are therefore relied on in their entirety, without scrutiny, which based on the magnitude of

the implications of the report, is completely inappropriate.

And so, despite Council’s promise to investigate the 1 in 100 levee for North Wagga, despite it being the

most morally, socially and economically solution favoured in all prior flood studies, and despite having all

the resources to do it, accorded by the State Flood Policy, Council seem to be actively manipulating

information in order to justify their agenda to exclude North Wagga from adequate flood protection. It

seems predictable therefore that Council and the Floodplain Committee could not answer the questions

raised by the Association in a letter dated 25th January, pertaining to validity of the pivotal arguments used

in the 2018 FRMP to discount a 1 in 100 levee for North Wagga, which resulted in the initiation of a Peer

Review.

Page 14 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

(3) Critical information presented in all preceding flood reports, that

favour a 1 in 100 levee for North Wagga, is omitted and contradicts

arguments used in the 2009 FRMP to support the recommendation of

a 1 in 100 levee upgrade for Central/CBD.

Flood Committee members change every four years.

It is necessary to establish that there is a possibility the Floodplain Committee deliberating over the 2018

FRMP (established Feb 2016) were not privy to information contained in the 2009 FRMP and preceding

flood reports. If Council did have an agenda to spend as little money as possible in North Wagga, there is

a high chance that any discrepancies between the two major flood documents and the preceding flood

reports would go unchallenged. We understand that the only Councillor to have been involved at every

stage and level of the flood risk mitigation since 2005 is Councillor Kendall.

The 2018 FRMP claims North Wagga levee was a key aspect investigated in the 2009 FRMS&P

The 2018 FRMP states that “Consideration of changes to the North Wagga levee was a key aspect

investigated in the 2009 FRMS&P”. This statement is misleading to Committee members who are not privy

to the information contained in this report, because North Wagga hardly features in it. The 2009 report is

essentially a description of the study area, issues, feedback, and flood mitigation measures. The upstream

impact of a 1 in 100 Main City levee on North Wagga is not mentioned, nor are the economic and emotional

costs incurred by North Wagga residents because of regular flooding. The report goes on to say “The

implications of raising the North Wagga levee were discussed in detail by the Committee, including issues

of equity, risk and impact, cost benefit, the history of the current design level and what benefit a higher

levee would actually achieve. It was finally agreed, that while it is not appropriate to raise this levee, it is

essential to maintain the same relativity of protection with the main city levee”. We are of the view that it

is not possible for the Committee to fully consider equity, risk, and impact without any of the relevant

information.

The Main Arguments used against the 1 in 100 levee for North Wagga contradict all previous flood reports:

The six main arguments presented in the 2018 FRMP as justification for not providing North Wagga with a

1 in 100 levee are in our view seriously flawed. They are as follows:

(i) The upstream impact is unacceptable;

(ii) North Wagga Residents would have a false sense of security and become complacent about flood risk,

increasing the risk that people would not evacuate on time in a flood event, which is an unacceptable risk

to life;

(iii) It is not aesthetically pleasing;

(iv) high capital costs and construction difficulties;

(v) development behind the levee in North Wagga will increase; and

(vi) North Wagga will become a swamp for longer.

Page 15 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

(i) The upstream impact of a 1 in 100 levee is unacceptable

This is one of the major arguments used against the 1 in 100 levee, and scores a -3 in the Matrix, however

there is little evidence provided to back it up and it contradicts preceding reports by WMAwater and Public

Works.

Firstly, the information supporting the recommendation to upgrade the Main City Levee to a 1 in 100 levee

in the 2009 FRMP contradicts the information supporting the recommendation to not pursue a 1 in 100

levee for North Wagga in the 2018 FRMP. The 2009 FRMP recommends a 1 in 100 levee upgrade for

Central/CBD, which will have an upstream impact on North Wagga of 0.2m, which was deemed acceptable

at the time. In the 2018 FRMP, this is the same upstream impact that WMAwater tells us the 1 in 100 North

Wagga levee will have, but in this report, they deem it “significant” and “unacceptable” because it would

create an upstream effect on a “significant number of properties” of “up to 0.2m across the floodplain”.

Not only is it contradictory, this argument is also misleading, for two reasons – (i) The number of affected

upstream properties is not specifically provided; and (ii) the description of “up to 0.2m across the

floodplain” implies a blanket effect which must be apocalyptic if 174 properties have to be flooded to avoid

it as indicated visually in Diagram 9. Had the more detailed information as outlined in previous flood

studies been provided in the 2018 FRMP, the argument that the upstream effect of a 1 in 100 levee in

North Wagga would not hold up. Previous reports provide clear evidence that the upstream effects are

insignificant.

On Page 64 of the 2015 economic appraisal of the 1 in 100 North Wagga levee, the then Public Works

Department (“Public Works), provided the following breakdown of the upstream effects that a 1 in 100

levee in North Wagga would have. They are:

0km – 2km between 100mm – 200mm

2km – 3km between 50mm – 100mm

3km – 5km between 20mm – 50mm

According to Public Works, not only is the upstream effect limited to properties no more than 5km away

from the pinch point between Parken Pregan Bridge and Wiradjuri Bridge, but more specifically, the 0.2m

effect is limited to only those properties within approximately 1km of the pinch point (which will now be

referred to in this submission as the “hot spot”). Beyond the 1km distance, the effect tapers off

significantly. As such, this effect is described by Public works as “small”. The report also confirms that the

upstream properties affected total 18, and they were all consulted during the mandatory community

engagement meetings which resulted in majority support for the 1 in 100 North Wagga levee. This

information puts Diagram 9 into perspective – it is visually misleading.

On Page 50 of the 2014 Flood Model Revision Part 1 report, Section 6.10.3 entitled “1% AEP event – Main

City Levee and North Wagga impact” confirms that “the 1% AEP results for when both levees are

implemented do not vary significantly when only the Main City Levee is implemented. The impact is so

insignificant that for results of the likely impact of a 1 in 100 North Wagga levee, we are referred to Section

6.10.1 on Page 50 outlining the upstream effects of the 1 in 100 Main City Levee. The report goes onto say

Page 16 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

“The majority of the impacted region is sparsely populated and the relatively small impacts in relation to

the freeboard (0.5m) will minimise any additional over floor flooding. In contrast to impacts, there are

substantial benefits associated with the levee being upgraded……overall implementation of the new levee

alignment will largely improve flood mitigation in Wagga region”.

It is our view that the 2018 FRMP deliberately lacks the necessary detail about the actual upstream impacts

of a 1 in 100 levee in North Wagga and as such gives the impression necessary to effectively discount the

option for North Wagga.

(ii) If protected by a 1 in 100 levee, North Wagga Residents would have a

false sense of security and become complacent about flood risk, increasing

the risk that people would not evacuate on time in a flood event, which is

an unacceptable risk to life.

The argument that contributes most to the negative score associated with the 1 in 100 levee option for

North Wagga is the unacceptable Risk to Life and subsequent impact on SES, with an overall combined

score of -9 in the Multi Criteria Assessment Matrix. The argument hinges on two alleged facts - that

Residents will become complacent about evacuation and lives will be at risk when the village becomes a

low flood island, both considered by Residents to be seriously flawed.

The 2009 and 2018 FRMPs are contradictory about the issue of complacency.

In the 2018 FRMP, WMAwater argues that because a higher levee provides extra protection and can lead

to a community being flood free for a period, it could make them complacent about evacuating on time. It

also states “Unfortunately, residents’ perception of their own safety can be overestimated, even with

significant community education efforts….Even the most compliant communities are at risk of not being

able to evacuate due to insufficient warnings time or unexpected increase in the rate of rise of flood

waters”. And so, justifies discounting the 1 in 100 levee option for North Wagga, despite the fact that the

village is described as acutely flood aware and evacuation compliant when compared to other NSW towns.

So how did Central/CBD get a 1 in 100 levee? It has not flooded in 57 years and Residents are described as

flood adverse, do not show up at flood meetings, do not have flood plans and compare unfavourably in

terms of complacency to other NSW floodplain towns. In stark contrast to the conclusions made in 2018

FRMP, the fact that Central/CBD is so dangerously complacent about flooding is ignored in the 2009 FRMP,

which deems the Main City Levee upgrade to a 1 in 100 acceptable because there are numerous egress

routes and the SES is committed to work closely with these occupants.

Page 17 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

The Low Flood Island Argument

As if to make a weak argument about complacency amongst North Wagga Residents more watertight,

WMAwater states that the risk to life is further exacerbated by the fact that North Wagga becomes a low

flood island. On the face of it, this does sound extremely dangerous. However, the report overlooks a

critical factor - North Wagga becomes an island at very early stages in the flood event, at a 1 in 10-year

level and this is why Residents are so evacuation compliant. Residents are acutely aware that if they don’t

evacuate on time, they can be isolated for days without power, water etc. It has been this way since the

‘74 flood. Residents were well and truly out by the time the levee was breached in 2012, despite the fact

that they hadn’t flooded for 19 years and had only 5 hours’ notice. Why? Because they know it gets cut off

early. It is in fact the perfect safety mechanism. With a 1 in 100 levee, Residents would be only too happy

to evacuate early to avoid being cut off, with a sense of relief knowing that for events up to a 1 in 100-year

flood, they will be returning to undamaged homes.

The fact that Central/CBD does not become a flood island and has several exit routes would in our view

only add to the complacency of an already flood adverse community and to the risk of life. To increase

protection for this community, is putting their lives in serious danger. Fortunately, when the ‘big one’ hits

Wagga, North Wagga residents will have been well and truly evacuated in the early stages, and the SES can

focus on convincing Central/CBD occupants to drop everything and run. The fact that North Wagga

becomes a low flood island is in fact a critical factor in the SES’s capacity to mobilise and keep as many

residents in Central/CBD as safe as possible.

Notwithstanding the above, the problem that a flood island poses can be easily remedied with a bridge/box

culvert in Mill Street allowing egress to the North East; a small railway station at the railway viaduct in

North Wagga near Byrnes Road, which would allow any stranded passengers to be collected by train, a

method utilised by the Police during the 1974 flood; or a bridge between Parken Pregan Bridge and the

new Wiradjuri Bridge allowing provision for escape into Wagga Wagga CBD. These are feasible options,

the costs of which far outweigh the Annual Average damage bill for flooding and the financial and social

costs incurred by residents.

(iii) A 1 in 100 levee in North Wagga is not aesthetically pleasing

If Council had brought this argument to the residents, a majority would have advised them that firstly, it

only effects a handful of residents. And secondly, a peaceful flood free life (for as long as possible between

floods) is far more beneficial than maintaining the streetscape. Further, the North Wagga levee will be no

more or less aesthetically unpleasing than the Main City Levee and it would be safe to say that a handful

of objectors would certainly not justify the decision to not upgrade the Main City Levee.

Our representative Dr Jenny Woods advised the Floodplain Committee that the 1 in 100 levee would look

like a “Knight in Shining Armor” to residents. She agreed that one or two residents would perhaps worry

about the height of the levee, but most residents, even those who live directly opposite the levee (of which

she is one and so is the author), would welcome the extra protection and consider the loss of street appeal

to be a worthwhile trade-off to having their homes destroyed regularly by flood.

Page 18 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

Residents also don’t believe Council are in a position to comment on this matter without consultation.

Ironically, the argument was not applied when the 1 in 100 Main City Levee was extended in front of twenty

odd homes in Wiradjuri. Why? Because it was absolutely critical for it to be located there if adequate

protection was to be afforded to the Central/CBD. Loss of street appeal was justified in this case to prevent

vast economic loss in the business sector.

(iv) A 1 in 100 levee may have high capital costs and construction

difficulties.

WMAwater argues that a 1 in 100 levee in North Wagga may impact private and public land and it may

need to be completely replaced, impacting construction practicality and cost estimates. WMAwater does

not seem to have any idea what challenges exist and are therefore not in a position to quantify them. And

yet it is used as an argument against adequate protection adding to the negative score given to Technical

Feasibility, namely -3 and -2 in the Matrix, indicating major and moderate issues, respectively.

As it happens, a portion of the levee currently sits on private land without easements. It is understood that

the majority, if not all these owners are very keen to secure a higher levee and so the argument about

private land issues is baseless. Also, it is a common Council activity to secure easements when it is in the

public’s best interest to do so. Under normal circumstances, the protection of a village from catastrophic

flooding would be considered significant reason to secure the necessary easements.

(v) Development behind the levee in North Wagga will increase if protected

by a 1 in 100 levee.

WMAwater suggests that North Wagga should not be protected with a 1 in 100 levee because the

subsequent easing of development restrictions would lead to an influx of development behind the levee.

This is a weak argument which does not justify the destruction of 174 properties in a flood event slightly

higher than a 1 in 20-year flood. Regardless, had Council discussed this issue with North Wagga residents

their concerns would have been immediately allayed because North Wagga is a village where people value

community and connection to place, over progress and development.

This very matter is discussed in our representative Dr Jenny Woods’ Thesis for the Degree of a Doctor of

Philosophy entitled “Experiences of community spirit in flood recovery: Exploring the opportunities for

community development”. While on the Committee, Dr Woods attempted to convince committee

members that there is little risk of over development in North Wagga, as her research reveals that the

residents thrive in the current environment, featuring large parcels of land, on which spacious gardens and

vegetables are cultivated, animals raised and social connections enhanced. It is a village in which Residents

place great importance on the space they have enjoyed for generations and would therefore be an issue

Page 19 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

which could be quite easily addressed if Council were genuinely interested adequately protecting North

Wagga.

(vi) North Wagga will become a swamp for longer

The notion that North Wagga should not be protected by a 1 in 100 levee because it will become a swamp

for longer, mentioned several times in the plan if the levee is raised, is flawed. Once again, Council did not

have this discussion with residents. Residents believe that having a little longer inundation if an upgraded

levy is overtopped is better than more frequent flooding (and more frequent damage events, displacement

etc) by having a lower levee.

The 2018 FRMP states “In flood events that overtop the North Wagga levee, floodwaters can be impounded

by the ring levee bank for many days or weeks. Accounts from residents of North Wagga have noted the

village becoming like a swamp following the 2012 event, as the contaminated floodwaters could not drain

until the river flood level had dropped”. The context of feedback on the issue of North Wagga being a

swamp is omitted. Residents in North Wagga have raised this in relation to council’s lack of vegetation

management impeding flow and causing extended periods of flooding, to make the point that vegetation

management needs to be addressed (to reduce flood risk and duration) rather than as an argument against

an increase in the levy.

Notwithstanding the above, in Section 7.2 of the 2009 FRMP, WMA confirms that geographically, there is

no drainage issue in North Wagga when it states “a profile of the surveyed levee heights indicates that the

downstream side of the levee is sufficiently low to allow most floodwaters to escape should the levee be

overtopped from the upstream side. The downstream side of the levee may require breaching to fully drain

the suburb and to assist in the reduction of ponding depth”. Once again, the two flood study documents

contradict each other.

(4) The cumulative effects on flood levels from the thickened

vegetation and the Main City Levee upgrade, which expose North

Wagga to the increased risk of a Council-made flood, are not

considered in the 2018 FRMP.

Council undertook a revegetation project in 2002, planting thousands of trees and shrubs in the 34ha

reserve situated between North Wagga and the river, even though the effects that vegetation has on flood

levels is well-known.

According to Peter Morris (former resident and former DMR employee with 30 years’ experience in

floodplain road and bridge design) the location of this revegetation reserve is a “hydraulically critical

location” between the two levees, known as a pinch point, where flood flow is most adversely affected due

to a narrowing in the floodplain.

Page 20 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

Following a study of the 2012 flood event it was established that the river conveyance had significantly

declined because far less water flowed in 2012 (3600 m3/s) compared to 1974 (5200 m3/s). WMAwater’s

2014 Flood Model Revision Report concluded that “the change in stage/discharge relationship at Wagga is

substantially due to vegetation changes on the floodplain that have occurred over time. More specifically

“a change in effective roughness of approximately 20% has led to the stage/discharge relationship changing

such that a given flow now produces relatively higher flood levels. A flow of 3,000 m3/s previously

produced a height of 9.9 m, the same flow is now estimated to produce a height of 10.1 m, an extra

200mm”.

The reserve is protected by the biodiversity protection legislation and cannot be touched. It has had eight

years to thicken since it caused the last flood and will likely have an even greater impact on flood levels in

the future. It is therefore a critical factor to take into consideration when exploring flood risk mitigation

options for North Wagga. It is not however a consideration in the 2018 FRMP.

Residents’ do wonder how it is possible, that Council was able to proceed with this revegetation project in

Wagga’s most vulnerable floodplain location and then ignore its obvious impact on our community. It is in

our view sheer negligence.

The Main City Levee also has an impact on flood levels of some 0.2m, according to WMAwater, which when

added to the thickened vegetation impact, will likely cause flood levels to rise by some 500mm or more.

In our view the impacts need to be considered if there is to be a genuine investigation of adequate levee

options for North Wagga. Residents believe that under the circumstances, the 1 in 20 levee is not adequate

however the impacts are excluded from the 2018 FRMP.

(5) The 2018 FRMP lacks assessment of intermediate Levee options.

The logic seems to be that while the 1% AEP levee gives a high BC ratio, indicating that it is economically

feasible despite the costs, there are “other concerns” which outweigh this, such that it is discounted from

further consideration. Notwithstanding the concerns highlighted in this paper in relation to the analysis

on the effects of a 1% AEP levee, this approach is flawed.

A standard approach in modelling any stepwise change is to model intermediate levels. So, to model only

1% and 5% AEP (i.e., a 5-fold range) is absurd. Surely an intermediate AEP should be modelled? A 5% AEP

results in a reduction in AAD of around $650k while a 1% AEP results in a reduction in AAD of around $1.3m,

so presumably an intermediate AEP will give an intermediate reduction in AAD but at a lower risk of other

issues such as loss of life.

Section 7.2 of the 2009 FPRM Study confirms that a 1 in 60 levee was in fact modelled. It is stated that

while the 1 in 100 levee showed only “small” increases upstream, the 1 in 60 levee showed less impact.

Wouldn’t it be logical for the Committee to seriously consider the 1 in 60 levee as a potential alternative?

Instead, without any further investigation and in the absence of any pertinent information, the Floodplain

Committee apparently discusses the issue of the 1 in 60 levee and was apparently in a position to consider

“issues of equity, risk and impact, cost benefit, the history of the current design level and what benefit a

higher levee would actually achieve” and conclude that the 1 in 60 levee was not appropriate.

Page 21 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

If there is a genuine concern for the adequate protection of North Wagga, it would make sense to start

with an investigation of the 1 in 100 levee, and work towards the most appropriate levee height. However,

it seems apparent that the two extreme levees were presented because Council had every intention of

discounting the 1 in 100 levee, bringing the focus back to the only levee they are willing to provide, whether

it meets the needs of the North Wagga community or not.

(6) The 2018 FRMP relies on a weak Matrix scoring system.

As discussed, the information presented for the investigation of each option for North Wagga is in our view

flawed and therefore for this reason alone, any multi criteria analysis relying on it is subsequently flawed.

However, it also appears that the scoring system is engineered to come up with negative scores for all levee

options (which Council does not want to implement) and a positive score for the Voluntary Scheme (which

Council does want to implement) through inadequate weighting and doubling up of categories with

negatives scores.

Firstly, the analysis includes the BC ratio which in our opinion is flawed. WMAwater inform us that the

Matrix is used to assess a broad range of issues, not accounted for in the BC ratio (presumably because

they are not quantifiable) to gain a better picture of the option’s feasibility. So how can a clearer picture

of an option be given when the BC ratio is included in the analysis? According to the Policy Guidelines,

Economic Merit should be limited to include matters concerning life cycle cost of management measures

and reduction in flood damage.

There are a number of flawed assumptions in the matrix, which were raised by Michael Friend in response

to the public exhibition of the draft plan but not addressed in the revised plan. The most critical of these is

that all criteria (with the exception of risk to life) are given the same weighting. Some will justifiably have

the same weighting, but some (e.g., technical feasibility) will not, or should be assessed differently – i.e., it

is either technically feasible or not. As such, scores are allocated to each criteria, often with little to no

justification, which then greatly affects the outcomes. Specific examples are provided later in this

document, but the inherent bias noted earlier to VHR and VP options has resulted in positive scores being

allocated in the matrix to these options, while very negative scores have been allocated to all North Wagga

levee options, greatly affecting the final scores and recommendations.

The matrix also omits the emotional trauma caused to North Wagga residents as a result of regular flooding

and the threat of regular flooding, making for a seriously skewed analysis, again detracting from the clear

benefits of implementing the 1 in 100 levee. We know that the constant stress of worrying about a flood

because the existing levee is only 12% rather than 5% (what it was constructed for) is significant,

notwithstanding the stress associated with being displaced and having to deal with the cleanup and repairs

more frequently as a result.

The matrix is also not applied consistently between locations. For example, at Oura a 1% levee has a -2 risk

to life and -1 impact on SES, at Gumly a 1% levee is given a -4 risk to life and -2 impact on SES (noteworthy

as Gumly would become isolated as well in a flood), yet a 1% levee (without road upgrade) at North Wagga

is given -6 and -3 for these criteria – the maximum possible. This implies further bias against any upgrade

of the North Wagga levee.

Page 22 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

Analysis of North Wagga Levee Options

Section 9.3.3 Page 111 notes increased complacency risk amongst North Wagga residents with greater

protection, yet with 22 years between most recent floods, evacuation was excellent (as also noted in the

report). The fact that North Wagga becomes an island likely increases evacuation compliance as people

do not want to be isolated for days without power, water etc. In fact, evacuation compliance is likely better

than in Central where people are complacent because they completely trust the levee – it could be argued

that risk to life and impact on SES is higher in Central as people don’t evacuate yet levee could fail causing

catastrophic flooding. The wording again implies a bias in the plan.

Option L3A – 1% AEP North Wagga Levee Upgrade

A 1% AEP levee results in over floor flooding in 9 East Wagga, 1 Gumly and 1 Eunony property. Level of

property damage of this appears minimal as Annual Average Damages (AAD) is less than $40k – most effect

is in East Wagga with around $4k/property. Yet the impact on properties outside of North Wagga of this

option is used as a major argument against this option, even though the level of damage appears small.

Diagram 9 (p136) makes no sense – why would some Central Wagga properties flood in a more frequent

event if central as a 1% levee? Unless this is referring to a 0.5% event (i.e., less frequent flood) – but the

wording states that this is flooding in a more frequent event. Greater clarification is required.

Multi-criteria assessment. On page 138 the impact on flood behaviour is given -3, but the fact that only 11

properties would experience minor flooding means this is excessive – suggest should be -1. Impact on

property damage is given -3 is also inexplicable. Given positive benefit overall should be +2. Technical

feasibility is given -2, but should be no worse than -1 as it is fairly straightforward (or again, as suggested

earlier, remove technical feasibility from the matrix – it is either feasible or not, and costs are included in

the BCA criteria). Impact on SES and risk to life should be not different to 1% Gumly levee – ie -2 and -4.

These adjustments would bring overall score to -2, rather than -13.

Option L3B – 1% AEP North Wagga Levee Upgrade with Hampden Ave embankment

On p139 it states that ‘several’ properties in East Wagga are negatively affected by this option, yet on p141

Table 50 shows positive benefit for East Wagga.

Table 52 – using same logic as for L3A, impact on flood behaviour should be -1, impact on property damage

should be +2, technical feasibility -1, economic/ecological benefits -1 (i.e., no different to L3A), impact on

SES should be -1 (easier access to north wagga in flood event, more time to evacuate etc), and economic

merits should be same as L3A (+3), giving overall score of 0 rather than -11 as it is.

Recommendation on p142 is not justified on this basis, as largely this is based on adverse flood impact on

other properties, which from the report is not significant.

Option L4A – 5% AEP North Wagga Levee Upgrade

On p150, the -10-score given to this option seems unrealistic based on previous arguments around L3A and

L3B. It should be at least positive if changes consistent with suggested changes for L3A and L3B are made.

The summary (p150) is direct cut and paste from L3A and B – i.e., ‘unacceptable adverse flood impacts on

other properties’ – yet no justification and less properties would be affected in this case – p147 states up

Page 23 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

to 0.05m increase in flood levels upstream (hardly unacceptable). This again implies a bias against any

levee upgrade to North Wagga.

Option L4B – 5% AEP North Wagga Levee Upgrade with Hampden Ave upgrade and Conveyance

improvements in Wilks Park

On p155 – a score of -7 is unrealistic based on previous arguments, and should be amended.

Option PR1 Voluntary House Raising and Voluntary House Purchasing Scheme

On p194 a score of +11 for this option is ridiculous. It does not have a +3 effect on property damage –

there is still damage to ground floor items (garages, a/c units, gardens etc)- at best it would be +2. Impact

on SES and risk to life should not be positive – raising houses may increase complacency and refusal to

evacuate – only those with raised houses or access to one, did not evacuate in 2012. Community

acceptance score of +2 is unjustified – not supported in previous consultation. The exceptionally positive

scores assigned to criteria for this option, without any justification, again implies an inherent bias towards

VHP and VP.

Conclusion

In this document, the NWWRA has documented serious concerns around the 2018 FRMP, with the aim of

assisting BMT Group to undertake a robust and objective peer review. The document gives context

around the history behind discussion and decisions on flood mitigation options for North Wagga, which

clearly shows that a 1% AEP levee is the preferred option based on previous analyses and extensive

community consultation.

The 2018 FRMP ignores much of this prior analysis, and relies on flawed assumptions and analyses to

discount all 1% AEP levee options, and instead recommends a feasibility study into a 5% AEP levee, VHR

and VHP. The latter two options have been discounted in previous analyses and consultations, which

another feasibility study will confirm, leaving North Wagga residents with only one option – a levee that

does not offer the community the level of flood protection it is entitled to, and a greater cost to the

whole Wagga community (financial and social) as a result of more frequent inundation of North Wagga

than would be provided through an adequate levee for North Wagga. We trust that BMT Group will

objectively address these concerns in the peer review.

Page 24 of 25


NORTH WAGGA RESIDENTS’ ASSOCIATION MARCH 2021 | Fi Ziff

References

Floodplain Risk Management Plan and Study, WMAwater, May 2009

Flood Model Revision Report, WMAwater, August 2014

Levee Upgrade Detailed Design & Community Consultation Report PSRP-7, WWCC, 13 July 2015

North Wagga Wagga Levee Options and Third-Party Impacts Report, Public Works, 2015

Thesis for the Degree of a Doctor of Philosophy - Experiences of community spirit in flood recovery:

Exploring the opportunities for community development, Ms Jenny Woods, March 2017

Submission 135 to 2017 Draft FRMP, Michael Friend, Oct 2017

Minutes of Policy & Strategy Meeting, WWCC, 15 July 2015

Floodplain Risk Management Plan and Study, WMAwater, April 2018

Input for the submission came from the following individuals:

Professor Michael Friend – Pro Vice-Chancellor Research and Innovation, CSU. Co-opted Sub-Committee

member of the FRMAC and Resident of North Wagga Wagga.

Dr Jenny Woods – Support Coordinator for Trust Support Coordination Wagga, North Wagga Wagga

Resident and former Committee member of the FRMAC.

Fiona Ziff – A nobody with a little bit of savvy. Author of the Submission, Resident of North Wagga and

Co-opted Sub-Committee member of the FRMAC.

Page 25 of 25

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!