State Environment Protection Policy (Waters) Review 2015
Response to Discussion Paper
By Gippsland and Southern Rural Water
13 July 2015
State Environment Protection Policy (Waters) Review 2015
Southern Rural Water Submission
Contents
1
2
3
4
Background ...................................................................................................................................................................................................................................... 4
1.1
Purpose .................................................................................................................................................................................................................................... 4
1.2
Introduction ............................................................................................................................................................................................................................. 4
1.3
SRW obligations ....................................................................................................................................................................................................................... 4
1.4
Key points – WoV ..................................................................................................................................................................................................................... 5
1.5
Key points ‐ GoV ....................................................................................................................................................................................................................... 6
1.6
Further Information ................................................................................................................................................................................................................. 6
Macalister Irrigation District Background ........................................................................................................................................................................................ 7
2.1
SEPP requirements ................................................................................................................................................................................................................... 7
2.2
Schedule F5 .............................................................................................................................................................................................................................. 7
2.3
Why a 40% reduction target .................................................................................................................................................................................................... 7
2.4
SRW response .......................................................................................................................................................................................................................... 8
What have we learnt in recent years? ........................................................................................................................................................................................... 15
3.1
What research has been undertaken? ................................................................................................................................................................................... 15
3.2
What causes blooms in the Lakes? ........................................................................................................................................................................................ 15
3.3
Why do we monitor nutrients? .............................................................................................................................................................................................. 18
3.4
Where do the nutrients come from? ..................................................................................................................................................................................... 18
3.5
The influence of rainfall and flow .......................................................................................................................................................................................... 20
3.6
Is a 40% reduction target feasible.......................................................................................................................................................................................... 25
3.7
The role of nitrogen ............................................................................................................................................................................................................... 27
Questions from discussion paper................................................................................................................................................................................................... 29
4.1
Roles and responsibilities....................................................................................................................................................................................................... 30
4.2
SEPP usage ............................................................................................................................................................................................................................. 32
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4.3
SEPP (Waters)......................................................................................................................................................................................................................... 33
4.4
Feasible v aspirational ............................................................................................................................................................................................................ 33
4.5
Objective support................................................................................................................................................................................................................... 33
4.6
Socio/eco/enviro balance ...................................................................................................................................................................................................... 34
4.7
Trade offs ............................................................................................................................................................................................................................... 34
4.8
Uniform SEPP ......................................................................................................................................................................................................................... 34
4.9
Specific beneficial uses .......................................................................................................................................................................................................... 35
4.10
Classification system .............................................................................................................................................................................................................. 36
4.11
Spatial arrangements ............................................................................................................................................................................................................. 37
4.12
Segments ................................................................................................................................................................................................................................ 38
4.13
Stand‐alone segments............................................................................................................................................................................................................ 39
4.14
Beneficial uses........................................................................................................................................................................................................................ 39
4.15
Beneficial uses and segments ................................................................................................................................................................................................ 39
4.16
Additional beneficial uses ...................................................................................................................................................................................................... 40
4.17
Indicators ............................................................................................................................................................................................................................... 40
4.18
Usefulness of targets.............................................................................................................................................................................................................. 41
4.19
At risk areas ............................................................................................................................................................................................................................ 44
4.20
Knowledge gaps ..................................................................................................................................................................................................................... 45
5
References ..................................................................................................................................................................................................................................... 46
6
Attachment 1 ‐ SRW/WGCMA SEPP (WoV) Review Agreement .................................................................................................................................................... 47
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State Environment Protection Policy (Waters) Review 2015
Southern Rural Water Submission
1 Background
1.1 Purpose
1.2 Introduction
1.3 SRW obligations
The purpose of this paper is to document SRW’s response to the current review of the State Environment Protection Policy
(Waters of Victoria) and (Groundwaters of Victoria). Sections 2 and 3 focus on provisions contained within Schedule F5 of
the outgoing SEPP (WoV), along with general provisions associated with SEPP WoV and SEPP GoV. Section 4 contains
SRW’s direct response to the questions posed in DELWP’s discussion paper.
The State Environment Protection Policy (SEPP) for Victorian waters – including the Waters of Victoria (WoV),
Groundwaters of Victoria (GoV) and all associated Schedules – is being reviewed with the goal of producing a single, all‐
encompassing SEPP (Waters). The Department of Environment, Land, Water and Planning are responsible for the
development of the policy, whilst the Environment Protection Authority Victoria have been given the task of undertaking a
scientific review, including the development of new ‘segments’ and their associated water quality indicators and
objectives.
Southern Rural Water (SRW) has various obligations under the current SEPP (WoV). These include:
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Nutrient reduction management and monitoring in the Macalister Irrigation District / Gippsland Lakes (Schedule
F5)
Salinity management in the Macalister Irrigation District
Regional Environment Improvement Plan for the use of recycled water at Werribee Irrigation District
Review planning applications and reviews of DWMP’s which is an instrument of SEPP (WoV)
Manage groundwater licensing and use across southern Victoria
As such, SRW will be directly affected by the outcome of the review. This document is intended to provide SRW’s thoughts
and position with respect to the review and any possible changes to the SEPP.
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1.4 Key points – WoV
1.4.1
General Comments
1.4.2
DELWP Discussion
Paper: SEPP Usage
1.4.3
DELWP Discussion
Paper: Segments
1.4.4
DELWP Discussion
Paper: Usefulness of
Targets
Southern Rural Water Submission
The key points SRW wish to convey as part of this submission are detailed below. Additional supporting information in
regards to Schedule F5 requirements are contained within Sections 2 & 3 of this submission. Responses to ALL questions
from the DELWP discussion paper are contained in Section 4.
1. SRW supports the amalgamation of SEPP WOV and SEPP GoV into a single SEPP.
2. SRW has developed a common understanding with the West Gippsland Catchment Management Authority with
respect to SEPP WoV and the Macalister Irrigation District (see section 6)
3. SRW believes that the purpose of a SEPP should be to define the uses and environmental values to be protected in
Victoria and the environmental quality objectives needed to protect these beneficial uses. Accordingly it should
set the standards to be achieved not defer to the need for further research or the subsequent setting of standards.
4. The obligations within the SEPP (Waters) may incur additional burden, both regulatory and financial, and as such
any changes should be subject to a cost‐benefit assessment and consideration of who bears the cost.
5. SRW fully supports the inclusion of specific segment measures in the SEPP and in particular:
 retention of nutrient reduction requirements for the MID
 consideration of the inclusion of additional intensive agricultural areas such as Lindenow, Thorpdale, Werribee
South and the Macalister Irrigation Area (MIA)
6. SRW believe there is a major flaw with the use of nutrient load reduction targets, for phosphorous or nitrogen, as
an attainment measure with the previous target not having been met and historical monitoring data indicating
that rainfall is a major determining factor (i.e. there is 70% correlation between rainfall and nutrient discharges
from the MID).
7. SRW remains committed to current programs, such as the nutrient monitoring program, involvement in the MID
Sustainability Group and the support and implementation of the West Gippsland CMA‐produced Macalister Land
and Water Management Plan (2008).
8. SRW believe that maintaining a requirement for the ongoing implementation of a nutrient management program
promotes action at the source of diffuse pollution, and is therefore preferable to nutrient load reduction targets.
9. SRW (and the WGCMA) agrees that the CMA is the most appropriate organisation to prepare and administer
nutrient management plans (such as the MLWMP), in close consultation with and supported by key stakeholders.
10. SRW (along with the WGCMA) believes that any SEPP attainment program aimed at reducing nutrient inputs from
the MID should be based around Best Management Practice (BMP) implementation.
11. SRW (and WGCMA) acknowledges that there has been significant success with the governance and operational
model developed in the MID through both the strategic planning and implementation phases which in turn could
be replicated in other sub segments of the catchment.
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1.5 Key points ‐ GoV
Southern Rural Water Submission
The key points SRW wish to convey as part of this submission are detailed below. Supporting information and responses
to ALL questions from the DELWP discussion paper are contained in Section 4.
1.5.1
DELWP Discussion
Paper: Uniform SEPP
1. There needs to be consistency and/or clarity between groundwater and surface water in regards to segmentation,
sub‐segmentation, indicators and objectives. As an example, conflicts may arise where beneficial uses, indicators
and objectives do not align where there is a significant difference in the natural chemistry of groundwater and the
surface waters it is discharging into.
1.5.2
DELWP Discussion
Paper: SEPP Usage
2. SRW, as a regulator, requires additional clarification within the SEPP in certain circumstances i.e. brine disposal
and desalination projects. This will better facilitate the processing of applications.
1.5.3
DELWP Discussion
Paper: Beneficial Uses
3. The term ‘potable’ needs further clarification and should be considered for removal from the SEPP as a beneficial
use, as both the Department of Health and Human Services and water corporations as a whole warn against the
consumption of untreated water.
1.5.4
DELWP Discussion
Paper: Classification
System
1.6 Further Information
4. SRW believe there are potential alternatives for defining groundwater segments that may assist in streamlining
management of segments. SRW also believe sub‐segmentation of groundwater should not be discounted as there
are instances in which they may be warranted in a similar manner to surface waters i.e. high levels of human
intervention or influence.
SRW appreciates the scale and importance of the task given to the EPA and DELWP in reviewing the SEPP (WoV) and SEPP
(GoV). We thank both agencies in advance for considering this document and the position that SRW has taken in regards
to the SEPP review. SRW have, and will continue to, engage with the EPA and DELWP on matters regarding the review.
For further information please contact;
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2 Macalister Irrigation District Background
2.1 SEPP requirements
Since its original gazettal, a number of Schedules have been added to the SEPP (WoV) focussed on particular segments in
the Victorian landscape. Schedule F5 was created in 1996 to represent the Latrobe, Thomson and Merriman Catchments,
but also prescribed actions to reduce the impacts on downstream beneficial uses, such as those associated with Lake
Wellington and the Gippsland Lakes. It includes a specific objective of reducing phosphorous loads emanating from the
Macalister Irrigation District (MID) by at least 40% from a specified baseline load by the year 2005. The direct excerpt from
Schedule F5 is shown below:
2.2 Schedule F5
2.3 Why a 40% reduction
target
There is relatively little information available that details the reasoning behind the 40% reduction target, however Hart &
Cottingham (CRCFE, 2000) discusses an analysis by the EPA that concluded a 40% reduction of nutrients into Lake
Wellington was required to move the Lake from a eutrophic to a mesotrophic state. This 40% reduction related to the
entire Western catchment load but provides apparent context for the MID target.There are also elements in the available
literature that allude to the target and its overall context, i.e. that a 40% reduction in phosphorous loads from the MID will
reduce the western catchment loads by approx. 10% (Webster et al, 2001).
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2.4 SRW response
2.4.1
Nutrient reduction plan
Throughout the late 1990s, SRW in association with the Department of Natural Resources and Environment (DNRE),
Environment Protection Authority (EPA) and local farmers developed the Macalister Irrigation District Nutrient Reduction
Plan (MIDNRP). It was finalised and lodged with the EPA in November 1998 in fulfilment of our obligation under Clause 15.1
of F5.
The MIDNRP was reviewed and replaced by the Macalister Land and Water Management Plan (MLWMP) in 2007. The Plan is
administered by the West Gippsland Catchment Authority; however SRW maintains a key role in nutrient management under
the Plan. The MLWMP is due to be reviewed in 2016/17.
2.4.2
Nutrient baseline
There has been considerable controversy about the baseline total phosphorus (TP) load from the MID, with claims and
counter claims about the best estimate (many different methods were used, and all had problems because of a lack of
adequate data). (CRCFE 2000)
The EPA requested the CRCFE to facilitate a specialist workshop, attended by many key stakeholders, to resolve the issue
regarding the estimation of loads from the MID. The purpose of the workshop was to seek agreement on a “best”
methodology and a “best” available data set, and if needed to define what additional data needed to be collected.
The Workshop participants identified a number of constraints to the EPA’s requirement that a baseline TP load be estimated
for a “median” year, using the loads discharged during the years 1994, 1995 and 1996. Those constraints were:
•
•
•
•
There was no adequate water quality data for the years 1994‐96.
Water quality and flow data was available for two MID drains for the period 1997‐99, but there was no
well accepted method for extrapolating the data for the whole MID or for the desired period (1994‐96).
The period 1994‐96 was relatively wet while 1997‐99 was very dry.
There may have been changes in land use or irrigation practice during the period between the two dates
(although the participants from the MID region believed that there were only minor changes).
The Workshop concluded that there were uncertainties associated with each of the methods for estimating the baseline TP
load from the MID. It was therefore important that the method adopted be transparent so that any limitations in the results
would be clear. (CRCFE 2000)
The baseline phosphorus load discharge during the years 1994‐96 was established as 70 tonnes per annum using a process
agreed to by all stakeholders and detailed in a report by the EPA, Total Phosphorus Loads from the Agricultural Drains in the
Macalister Irrigation District, published in December 2000. The report discusses the uncertainties in the baseline estimate in
detail.
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2.4.3
Nutrient target
Southern Rural Water Submission
The SEPP sets a target of a 40% reduction in nutrient (phosphorous) discharges by 2005. This means reducing discharges
from 70 tonnes to 42 tonnes per annum. The target was not met and while there is no current target, SRW continues to
report against the target.
A review of both the drain based and river based monitoring systems has highlighted the strong correlation (70%) that exists
between rainfall and nutrient discharge (refer to Section 3 for details).
2.4.4
Nutrient monitoring
While not specifically required in the Schedule, SRW has monitored nutrient discharge since 1997 to ascertain whether the
target was being met.
2.4.4.1 Drain monitoring program
SRW initially developed a nutrient monitoring program with a focus on the drainage network.
To ensure a direct comparison was possible between the baseline and future phosphorus loads, the same broad
methodology used to calculate the baseline phosphorus loads was also applied to the calculation of future loads. This
approach was developed and agreed to by key stakeholders (such as the Department of Natural Resources and Environment)
and was confirmed and endorsed by the EPA with a document titled Protocol for Calculating Phosphorus Loads for the
Macalister Irrigation District, published in February 2001.
The drain‐based model had sixteen monitoring sites (Figure 1) that took mean daily flow and TP concentration at different
intervals depending on the likely contribution from a given drain. Where there was sufficient data (in terms of frequency and
quality), the total load for each relevant drain was calculated. For those drains with insufficient data existed TP was
calculated with a mathematical relationship based on drain flows, land use and drain type (i.e. natural or man‐made).
The drain‐based monitoring program was in place for over 10 years. Over that time, significant changes began to occur in the
district, such as increased drain harvesting downstream of monitoring sites and shifts in land use. This made data collected in
the district unreliable, as it was no longer an accurate representation of the nutrient load exiting the district. Additionally, a
review highlighted that the model did not account for nutrients entering the MID from upstream sources, provided limited
scope for checking data accuracy and was due for expensive equipment replacement (Lowe & Sharpe, 2014).
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Figure 1 SRW drain‐based nutrient monitoring sites
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2.4.4.2
Southern Rural Water Submission
River‐based monitoring
Following the review of the drain‐based model, SRW implemented a new, river‐based monitoring program.
The program works on a broader scale than the previous program. It captures TP and flow data from four sites ‘upstream’ of
the MID, to measure the nutrient load entering from outside the district. It then captures the same data at four sites
‘downstream’ of the MID (see Figure 2 for sampling locations). The estimated nutrient load from the MID is considered to be
the total downstream load minus the total upstream load.
Additional to quantifying the phosphorous inputs from upstream of the MID, the new model also recognizes the inputs from
unirrigated, ‘dry land’ practices occurring within the district. A mathematical model calculates the estimated input from these
areas based on flow scenarios and typical nutrient contributions associated with specific land use activities. The load from
these areas is separated from the MID’s estimated contribution in the model and report.
The new monitoring regime was developed by Jacobs SKM for SRW, in consultation with the EPA, WGCMA, DEPI and
Gippsland Lakes Ministerial Advisory Committee and is regarded by all to deliver a superior estimate of phosphorous
discharges from the MID. Details of the model are contained within the review and model development paper by Lowe &
Sharpe (SKM, 2014).
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Figure 2 SRW river nutrient monitoring sites
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State Environment Protection Policy (Waters) Review 2015
2.4.5
Reducing nutrient input
Southern Rural Water Submission
Southern Rural Water’s involvement in reducing nutrient input into the Gippsland Lakes is complex, as we provide the
infrastructure that transfers bulk water and associated nutrients, but are not in direct control of nutrient inputs throughout
the irrigation district. However, there are a number of ways in which SRW have, and continue to have, an impact in nutrient
reduction. These are largely captured in the Macalister Land and Water Management Plan (MLWMP), a document developed
and implemented by a number of key regional stakeholders including SRW. Key aspects of the MLWMP include;
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Farm Planning program
On‐farm irrigation and drainage program
Floodplain and off‐farm drainage management
SRW’s MID2030 modernisation project has also been an important facilitator for change through the District. Water savings
(up to 20,000 ML) and improved accuracy in delivery have reduced costs to irrigators and allowed investment in improved
on‐farm practices and re‐use systems, which in turn have helped reduce the amount of nutrient rich tail water entering and
more importantly leaving SRW drains. The increased accuracy also prevents significant water loss from outfalls, and whilst
this water is fresh it provides flow that can mobilise sediment and nutrients within drains.
While SRW has a limited capacity for direct control on nutrient inputs throughout the Macalister Irrigation District its actions
help to enable the adoption of improved farm practises by local irrigators.
2.4.6
SRW’s influence in the
MID
One of the most fundamental issues with the use of a nutrient load reduction target is that it is currently a burden essentially
‘shouldered’ by SRW in terms of compliance with the requirements of the current SEPP (WoV) Schedule F5. This
oversimplifies the responsibilities within a system that has a range of inputs and stakeholders, many of which are beyond the
direct control of SRW.
SRW is responsible for the harvest and provision of bulk water to the Macalister Irrigation District. It does so by operating key
infrastructure, such as Lake Glenmaggie and the irrigation network. This includes the channels and drains that transport
water to and from customer farms in the MID. However, once water is delivered to a customer it can be used at their
discretion. The application of phosphorous and nitrogen‐based fertilizers, in terms of specific product, timing and rate of
application, is also the prerogative of the landowner. This illustrates the challenges SRW face in terms of reducing nutrient
loads in the drainage network, as it cannot physically regulate the various nutrient inputs across the District.
SRW has been, and continues to be, involved in a range of stakeholder groups, plans and initiatives that seek to promote and
provide incentive for changes to farm practices in the MID, specifically aimed at reducing nutrient loads to the Gippsland
Lakes. Many of these have been previously mentioned; involvement in the MID Sustainability Group, development and
implementation of the Macalister Land and Water Management Plan, the MID2030 modernisation project, and ongoing
support of on farm improvement initiatives. This, however, is the extent to which SRW can manage nutrient inputs
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State Environment Protection Policy (Waters) Review 2015
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throughout the MID; through influence and facilitation.
In summary, SRW’s lack of direct control over on‐farm nutrient inputs in the MID raises similar issues to those presented by
the effects of rainfall; that SRW’s ability to meet a nutrient load reduction target may, from year to year or over the long
term, be compromised by factors beyond its control. Notwithstanding this, we are mindful of the potential impacts of
nutrients exiting our drains and as such have been an active partner in attempting to reduce nutrient discharges into the
Lakes.
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3 What have we learnt
in recent years?
We have learnt a lot more about the cause of BGA blooms in the Gippsland Lakes since the SEPP and, more particularly,
3.1 What research has
been undertaken?
Considerable research has been undertaken in recent years on the health of the Gippsland Lakes and in particular on the
cause of BGA blooms in the Lakes. The following studies provide excellent examples;
Schedule 5 were introduced.
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3.2 What causes blooms
in the Lakes?
Zhu & Lee (EPA and Monash University), Gippsland Lakes Modelling Scenarios, 2015
Cook (Monash University), ‘Nutrients aint nutrients’ commentary, 2014
Holland et al, Two hundred years of blue‐green algae in the Gippsland Lakes, 2013
Ladson. A, Importance of catchment sourced nitrogen loads as a factor in determining the health of the Gippsland
Lakes, 2012
Webster et al, The Gippsland Lakes Environmental Study: Assessing Management Options for improving Water
Quality and Ecological Function, 2001
Zhu and Lee (2015) found:
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Temperature and salinity are the primary factors that initiate Nodularia blooms in the Gippsland Lakes.
Phosphorus controls the size and severity of Nodularia blooms.
Sediment P rather than catchment load supply most of the P to support the development of Nodularia blooms.
Sediment P is released under hypoxic conditions, which is often initiated by high organic matter (carbon) delivery
following events such as floods
Even if the external loading is reduced, internal phosphorus loading from sediment store may prevent
improvements of water quality in the Gippsland Lakes in the short term
Reduced catchment nitrogen and phosphorous loads may promote the growth of N‐fixing cyanobacteria such as
Nodularia
Increase in catchment nutrient load will certainly increase the phosphorus accumulation in the sediment and
increase the severity of Nodularia blooms in the long term.
Perran Cook produced a simple commentary reflecting on his studies of BGA and nutrients in the Lakes:
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There are three broad sources of nutrients to the lakes; within the lakes sediment, catchment (including
agriculture) and bushfires
Reducing catchment nutrient loads will see long‐term benefits (over decades)
Blooms have been a historical feature of the Lakes according to core sediment samples
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Holland et al (2013) found:
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Two periods of eutrophication and therefore high rates of algal blooming in the last 200 years, pre‐opening of the
entrance and post‐World War 2
During both periods, eutrophic water caused bottom water anoxia and the release of sediment P triggering
blooms in the Lakes
Difficult to ascertain specific reason for eutrophication in most recent period, but most likely due to changing land
practices, high fertilizer use, irrigation and river regulation
Many blooms suspected or confirmed to be Nodularia coincided with fire and/or flood events in the catchment
Ladson (2012) found:
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Nitrogen does not build up in the Lakes as phosphorous does. It is largely lost through de‐nitrification.
Loads to the Gippsland Lakes are highly variable and largely dependent on flows (90% correlation between annual
loads and flows to the Lakes).
Risk is from continued ‘pulses’ of nitrogen that overwhelms the system’s ability to de‐nitrify.
Winter/Spring pulses can contribute to diatom/phytoplankton growth. By summer, nitrogen stores are depleted,
anoxic sediment conditions lead to release of sediment P and prime Lakes for blooms of nitrogen‐fixing blue‐green
algae such as Nodularia.
In terms of nitrogen contribution, when the effect of flow is removed there has been no trend in loads since 1978.
A reduction of 40% from the MID would only decrease catchment loads by a modest 3%
Webster et al (2001) found:
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Loads into the Lakes include a number of runoff events which are sufficiently large enough to flood the waters
with high nutrient concentrations that stimulate large algal blooms
High degree of inter‐annual variability in flows and therefore nutrient loads
Blooms can be caused by a range of conditions, mostly stemming from eutrophication, anoxic sediment
conditions, stratification, nutrients in the water column and sediment.
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In summary;
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Phosphorous is still considered the key nutrient triggering algal blooms, but contemporary understanding is that P
stored and released from the Lakes sediment has the greatest impact on BGA blooms.
Nitrogen also plays an important part in algal blooming, but it is largely dependent on the timing of inputs.
Nitrogen is more rapidly lost in the Lakes system.
Nitrogen loads are also very closely correlated to annual flows.
Focus should still be on reducing phosphorous in the first instance, but nutrients as a whole need reducing to stem
immediate inputs and the build‐up of nutrient matter in the sediment in the long‐term
Actions to reduce nutrient loads to the Lakes will see long‐term benefits
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State Environment Protection Policy (Waters) Review 2015
3.3 Why do we monitor
nutrients?
Southern Rural Water Submission
As previously discussed, the Macalister Irrigation District was recognized in Schedule F5 of the current SEPP as being a key
contributor of nutrients to the Gippsland Lakes. As such, a nutrient reduction target was set for the MID, which in turn
required the development of an EPA‐approved monitoring program to capture information on the nutrient load leaving
the District and entering the Gippsland Lakes.
The Gippsland Lakes system is particularly vulnerable to inputs from catchment area. The Lakes have a very large
catchment but only a small entrance, which increases the time water, and matter associated with the water, is retained in
the system. This can lead to significant issues with water quality. In this system, nutrients pose a major issue. Large inputs
stemming from the catchment enter the Lakes and either provide an immediate available resource, or settle into the lake
sediment. Phosphorous in particular is known to be stored in large amounts within the sediments, and can be released
into the water under certain lake conditions.
The focus on nutrients both entering and stored in the Gippsland Lakes is due to the significant impact they can have on
biological processes, and in particular blue green algae (BGA) blooms. There is a large body of literature analysing algal
blooming in the Lakes, and it is generally accepted that the frequency, scale and toxicity of BGA blooms has changed, for
the worse, since World War 2 (Holland 2013). This change has been accredited to elevated levels of nutrients, especially
phosphorous, entering the Lakes from catchment and providing an ideal environment for algal growth. There are also the
long term implications associated with phosphorous being stored in sediments and later being released, again influencing
BGA (Zhu & Lee 2015).
3.4 Where do the
nutrients come from?
Nutrient inputs to the Lakes stem from a very large catchment area, and come from a variety of sources. The MID, whilst a
relatively small part of the catchment in terms of area, is known to contribute significant nutrient loads. Quantifying the
various sources and loads to the Lakes, including those from the MID, has been an ongoing challenge, especially in a
system with high inter‐annual variability in conditions (Webster et al 2001). The following studies have all produced varied
results in regards to the MID alone;
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Around the time of inception of SEPP Schedule F5, the total estimated load of P to the Gippsland Lakes from the
Western catchments was 190 tonnes per annum and the contribution from the MID was given a baseline value of
70 tonnes per annum (details in Section 2.4.2 of this submission).
Further work by Webster et al (2001) highlighted that the MID contributed between 25‐30% of the total Western
catchment phosphorous load, and around 10% of the nitrogen load.
In a paper by Fox (2003), the total P load to Lake Wellington was listed as 220 tonnes/annum and the contribution
from the MID was considered to be 14%.
Grayson (2006) estimated total catchment P loads to be 329 tonnes per annum. According to Grayson’s modelling,
around 204 tonnes of the total P load stemmed from the Western catchments, and of that approximately 30%
originated from the MID.
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Southern Rural Water Submission
SRW’s own monitoring suggests that the estimated phosphorus load from the MID was between 23 tonnes (1996)
and 90 tonnes in (2001), averaging around 52 tonnes per annum. There is considerable variability in the annual
loads and it has been demonstrated that this is in part due to a correlation with rainfall.
Other key catchment sources of nutrients to the Gippsland Lakes include but are not limited to;
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Fire and flood events
Hill and streambank erosion
Point sources (i.e. sewage treatment plants and industrial areas)
Dryland agriculture
Forested area and natural sources
In summary, there are a number of sources contributing to nutrient loads entering the Lakes, and the Macalister Irrigation
District remains a key source. However, quantifying and monitoring loads is an inherently difficult task and there have been
significant differences in estimates throughout the literature.
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3.5 The influence of
rainfall and flow
Southern Rural Water Submission
Analysis of the data collected by SRW over the course of its nutrient monitoring program has determined a significant
relationship between annual Total P loads and annual rainfall1, as demonstrated in Figure 2 and Figure 3 below. Simply,
wetter years lead to higher loads and drier years see reduced loads.
Figure 1 Comparison between Annual Rainfall and P Load
1
Rainfall data taken from Maffra Township until data ceased, at which point data taken from Tinamba AWS
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Figure 2 Relationship between Annual Rainfall and P Load
The R² value of 0.70 in Figure 3 suggests that there is a positive relationship between the two variables. It is hypothesised
that the relationship may be due to a build‐up of soil moisture over time, increasing the rate at which the profile is
saturated in a rainfall event leading to greater volumes of runoff throughout the year. Additionally in higher rainfall years
there are typically episodic rainfall events that have the potential to mobilise and transport large nutrient loads. An
example of the influence of a high rainfall event was demonstrated in late 2014, when approximately 99 mm of rain was
recorded at Tinamba in 24 hours and the subsequent estimated daily nutrient load from the district was 15 times greater
than the average daily load for the previous 6 months (Figures 4 and 5 below).
Figure 3 Daily total P load – MID downstream sites
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The data further supports a long‐held understanding that significant rainfall, and the associated flows, lead to higher
nutrient loads. High rainfall increases overland runoff, mobilising nutrient matter and transporting it into the drainage
system. Flow in the drain system is increased, picking up inputs off farms but also moving sediment and nutrient matter
settled within the drain itself. High rainfall events also contribute to erosion of land and stream courses, including natural
stream lines that are utilised as part of the drainage network.
Figure 4 Daily rainfall
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Whilst rainfall can be seen to increase nutrient loads, there are also factors at play that increase the periods of relative
‘dry’ weather, or lack of flow within the drainage network, that suppresses consistent nutrient contribution to the end of
the system. The reduction in flows within the drain system has occurred due to two key initiatives; the modernisation of
the irrigation district and the promotion and implementation of a range of on‐farm best management practices (BMP’s). It
is worth mentioning the two initiatives together, as the implementation of the MID2030 modernisation project has
generated water and efficiency savings that have spurred on changes to on‐farm practice.
The MID2030 project has been undertaken to transform the out‐dated Macalister Irrigation District infrastructure into an
efficient system using modern technology. The installation of flume gates and electronic meters have increased the
accuracy with which water can be measured and delivered, which in turn reduces the risk of excess water escaping to
outfalls and into the drainage network. This contributes to reducing the base flow in drains and therefore the capacity to
mobilise and transport nutrients. An estimated total of 20,000 ML of water has been saved to date through modernisation
(pers. Comm. M. Budahazy (SRW) 2014).
The water savings generated by MID2030 have also helped promote investment on farms to maximise the use of water
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and, in particular, tail water. There are a range of methods that have become commonplace for efficient water use and
reducing water and nutrient losses off farm, such as laser grading of paddocks, conversion to spray irrigation and the
installation of re‐use or drain harvesting systems. The obvious benefit is that during irrigation periods, the volume of
runoff entering the drainage network from farms is significantly reduced, preventing nutrient matter from leaving the farm
system and again decreasing the drains base flow and ability to mobilise and transport nutrients.
The issue of climate change may considerably influence the nutrient output from the MID into the future. There could be a
reasonable assumption that, as the effects of climate change begins to influence the Gippsland Lakes catchment, we could
expect to see decreased annual rainfalls, continued change in on farm practice to account for decreased water availability,
and an increase in ‘episodic’ weather events, such as large storms. If this were to eventuate, it would appear likely that we
would see even more influence on nutrient loads from rainfall events as opposed to consistent inputs from the MID
drainage network.
In summary, the improvements in the operation of the MID have increased the periods of ‘dry’ conditions through the
drainage network, which prevents the consistent mobilisation and transport of nutrients to the end of the system. This
further exacerbates the effect that rainfall has on nutrient loads, as the contribution during rainfall and subsequent high
flow events becomes even more influential on the total loads experienced during any given year. This raises a significant
point regarding the use of a nutrient reduction target as an attainment measure in the SEPP. Whilst SRW has, and
continues to, implement and promote change in the district that influences drain base flows and nutrient contribution in
dry conditions, SRW obviously cannot account for the natural variability of rainfall, in terms of its volume, intensity and
timing. Ultimately, this means the ability of SRW to comply with a nutrient load reduction target is at least in part
compromised by and dependent on annual rainfall.
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3.6 Is a 40% reduction
target feasible
3.6.1
INFERR analysis –
feasibility and cost of
nutrient reduction in the
Gippsland Lakes
In December 2009 a report was released that contained the details of an Investment Framework for Environmental
Resources (INFERR) analysis conducted for the Gippsland Lakes. The report was produced with input from a variety of
Gippsland Lakes experts and stakeholders, and in essence delivered a feasibility and cost‐benefit analysis for management
options for the reduction of phosphorous loads to the Lakes. Whilst the report was not exclusive to the MID (e.g. it
included dry land farming as well as irrigated), the findings help illustrate both how SRW’s current efforts are well
targeted, and also provides a realistic picture of the feasibility of achieving nutrient reduction targets.
The INFERR analysis initially set out to look specifically at the 40% reduction of P load to the Gippsland Lakes, but on
further research it was decided that various P load reduction targets and funding scenarios would also be assessed to
provide a more realistic picture of nutrient management options. Importantly, the 40% reduction target was described as
‘difficult to justify on the basis of being a cost‐effective public investment’ (Roberts et al. 2009). In fact, the report
determined that, whilst technically feasible, a 40% reduction in P would require huge funding (Approx. $990 million over
20 years) and major changes in land use away from agriculture. Comparatively, 10% and 20% reductions were assessed as
being a much better target in terms of cost‐effectiveness and feasibility. Over 20 years, the costs of these two alternatives
were estimated at $16.5 M and $80.2 M respectively.
As important as quantifying the costs associated with nutrient reduction is the way in which the report highlights the
management actions that can achieve the reductions, as they are prioritised by both their dollar value and practicality. The
outcomes of the analysis on four nutrient reduction targets are shown in Table 1 below;
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Table 1 Report on the Gippsland Lakes INFERR Analysis, Roberts et al., 2009
As the results show, the actions currently being taken by SRW in terms of the modernisation of the irrigation district and
the promotion of best management practices through vehicles such as the Macalister Land and Water Management Plan
are reflected by the suggested options within the INFERR analysis. The table also shows the major financial and social
obstacles that reduce the feasibility of a 40% reduction target.
The INFERR analysis provides some food for thought for two aspects of the SEPP review;


how achievable the current nutrient load reduction target is when analysed against costs and feasibility of
management practices, and how a future nutrient reduction target will capture feasibility information and ensure
that targets are attainable within the lifetime of the new SEPP (i.e. 10 years);
the validity of SRW being the party held accountable to any SEPP requirements (such as a new nutrient reduction
target) when the majority of available management actions are outside of SRW’s direct control (although
encouraged by SRW).
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3.7 The role of nitrogen
3.7.1
Algae and nitrogen in the
Gippsland Lakes
There is considerable literature detailing the increase in algal bloom frequency and severity within the Gippsland Lakes
since the 1980’s (Holland et al 2013). As for phosphorous, nitrogen is seen as a contributor to this issue due to its potential
influence on algal development. The current understanding around nitrogen is that inputs from the catchment can have
significant effect on the type and timing of algal blooms, based on the timing of nitrogen input. For example, if there are
high nitrogen loads over the cooler, wetter months, conditions within the Lakes become suitable for the release of
phosphorous stored in the Lakes sediment (Ladson, 2012). Leading into summer, the released sediment phosphorous,
combined with decreasing nitrogen levels, can lead to large blooms of the nitrogen‐fixing toxic blue‐green algae Nodularia.
Conversely, if there are ongoing nitrogen inputs from the catchment during the warmer months, the increased availability
of N reduces the competitive advantage of Nodularia as a nitrogen‐fixer, but may lead to the blooming of other algal
species such as Synocochoccus.
Regardless of the advances in understanding around nitrogen’s influence in terms of algal blooming, there are still some
key points that reduce its relative usefulness and practicality in terms of monitoring to that of phosphorous in the MID;






recent modelling has confirmed the understanding that it is phosphorous stored in sediment, and salinity, that has
the most significant influence on seasonal algal blooming, particularly of Nodularia (Zhu & Lee 2015)
Nitrogen is naturally much more abundant in the landscape than phosphorous and would therefore be more
difficult to separate in terms of natural inputs and additional inputs from farming practices
Nitrogen is lost from the Gippsland Lakes system via de‐nitrification and is not stored as readily as phosphorous
within the sediment, and so its influence appears to be as dependent on timing of input as total load (Ladson
2012)
Based on available data, Ladson (2012) estimated that a 40% reduction in nitrogen loads from irrigated areas
would only reduce total nitrogen load inputs to the Gippsland Lakes by approximately 60 tonnes, or 3%
Ladson (2012) found that once the effect of flow is removed, there has not been any discernible increase or
decrease in nitrogen loads to the Gippsland Lakes since 1978. This indicates that whilst there has been an increase
in load historically (since pre‐European settlement) due to changes in land use and agricultural practices, the
anecdotal evidence suggesting recent increases in nitrogen fertilizer use in the MID has led to increased nitrogen
loads to the Gippsland Lakes does not appear to be supported by data
Ladson (2012) also discusses the correlation between annual nitrogen loads and flow. There is a very significant
relationship, whereby 90% of the variance in loads can be explained by flow into the Gippsland Lakes.
Whilst there is strong evidence suggesting nitrogen is a contributor to algal blooms, it is difficult to compare its influence
in the Gippsland Lakes to that of phosphorous. Inputs of nitrogen are also extremely dependent on flows into the Lakes,
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increasing the difficulty in attempting to separate the impacts of the MID and, more importantly, determining the success
of any actions taken to try and reduce the load inputs stemming from the MID.
3.7.2
Monitoring nitrogen –
the issues
For nitrogen, there are some key issues associated with monitoring, and even greater issues with the setting of a load
reduction target. The following points support this assertion;




3.7.3
Nitrogen and the MID
Natural abundance in the landscape, increasing the difficulty in discerning the origin of N.
Similar issues to the original target for phosphorous with very limited data available to set a base load from which
to derive any target.
Again, similar issues apply in regards to nitrogen as they do for monitoring phosphorous i.e. that external factors
such as rainfall and flow have significant influence (Ladson 2012).
Hence there are questions around the validity of a nitrogen load reduction target as a suitable regulatory measure
to be included as an attainment program in the upcoming SEPP.
SRW believe that nitrogen should be recognized and managed in the SEPP in much the same way as suggested for
phosphorous moving forward – through continued promotion of best management practices (BMP’s) on farms throughout
the MID and the implementation of nutrient reduction plans (such as the ML&WMP).
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State Environment Protection Policy (Waters) Review 2015
Name:
Southern Rural Water Submission
Organisation: Southern Rural Water
Date: Monday 13th July, 2015
This template is provided to help you respond to the State Environment Protection Policy (Waters) discussion paper. Please answer as many or few questions as
you would like to provide input for. All submissions will be considered by DELWP in the development of the draft policy and policy impact assessment. Any
group or individual that provides comment will be kept informed and included in further consultation.
The information you provide in your submission will only be used by DELWP and EPA for the purpose of reviewing Water SEPPs. However, it may also be disclosed
to other relevant agencies as part of the consultation process. All submissions will be treated as public documents and may be published online for public access.
While formal requests for confidentiality will be honoured, please note that freedom of information access requirements will apply to all submissions.
If you wish to access information in your submission once it is lodged with DELWP, you may contact the SEPP (Waters) Review team by email at
Water.SEPPreview@delwp.vic.gov.au.
4 Questions from
discussion paper
Any general comments on the
proposed scope of State
Environment Protection Policy
(Waters):
Please enter your response
SRW support the amalgamation of the SEPP (WoV) and SEPP (GoV) into a single SEPP (Waters)
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State Environment Protection Policy (Waters) Review 2015
4.1 Roles and
responsibilities
Question 1:
What is your understanding of your
roles and responsibilities under
Water SEPPs?
Southern Rural Water Submission
SRW, in line with other water corporations throughout Victoria, is committed to the ongoing promotion of the objectives of
water SEPP’s and to protect and improve the quality of Victoria’s waters while providing for economic and social
development. SRW also support a risk‐based approach to regulation moving forward.
SRW currently use aspects of the SEPP to measure environmental performance in a number of areas. This occurs directly,
such as through nutrient load reduction targets for the Macalister Irrigation District, or indirectly as the values behind
overarching management plans such as the Regional Environment Improvement Plan that dictates recycled water use in the
Werribee Irrigation District. In this sense, SRW utilise the specific indicators and objectives outlined within the current SEPP.
Roles and responsibilities specific to SRW are discussed in more detail below.
Our role is clearly defined under the SEPP in that SRW must in conjunction with others develop a nutrient reduction plan to
reduce nutrient loads by at least 40% by 2005.
What is not clear is:
4.1.1
Roles and
responsibilities ‐ MID



A major anomaly in the SEPP, and particularly Schedule F5 is the governance framework and in particular:




4.1.2
Roles and
responsibilities ‐
Salinity
What our obligations beyond 2005?
What happens if we do not meet the 40% reduction target?
Do we have to monitor up to 2005 or continue monitoring beyond 2005?
what is the basis for determining the suitability of a nutrient reduction plan
what supervision or reporting is required
what is the consequence of failing to meet targets
what is the imperative/obligation to continue with the plan beyond 2005, irrespective of the outcome?
SRW manages groundwater control pumps in the Macalister irrigation District on behalf of its customers. The pumps lower
water tables that cause land salinization. The pumping rates and salinity are monitored to ensure discharges comply with
the SEPP.
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SRW, in conjunction with Melbourne Water, implements a Regional Environment Improvement Plan (REIP) for its Werribee
Irrigation District (WID). The need for an REIP was triggered due to SRW’s use of Class A recycled water from the Western
Treatment Plant for supplementing water supply to the WID.
4.1.3
Roles and
responsibilities – other
areas
The REIP was developed in line with EPA Publication 464.2 (2003) – Use of Reclaimed Water, which is intended to cover off
on requirements within the SEPP (WoV) and SEPP (GoV). An annual report is produced regarding the REIP and provided to
the EPA for approval. However, SRW are concerned that;



Monitoring for the REIP has been ongoing for 10 years
There is no specific attainment program, only a requirement that beneficial uses are not impacted
Many of the targets and objectives in receiving waters are exceeded prior to reaching the point of interaction with
SRW drains
SRW interacts with the SEPP as the licensor and regulator of groundwater use in southern Victoria;

Ensures that beneficial uses are taken into account when processing applications, such as for landfills, irrigation with
recycled water and quarries
Areas that are unclear are:
4.1.4
Roles and
responsibilities ‐
Groundwater




Points around REIP monitoring as above
Our role as the regulator for in‐situ desalination projects could be clearer given the statements in the current SEPP
around brine disposal in comparison to the in‐situ desalination guidelines
We monitor for saline intrusion in groundwater as a potential threat to the resource – this is not clearly defined in
the SEPP
Current interaction between the groundwater and surface water SEPPS needs clarity where groundwater and
surface water interact and what SEPP indicators or objectives should apply given the often large differences in
natural chemistry.
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Surface Water
SRW currently interacts with the Water SEPP’s as detailed in Section 4.1, and in that sense uses the SEPP’s to guide SRW’s
actions in regards to compliance with broad and specific targets and objectives. SRW have some concerns and suggestions
around interactions with the SEPP;


4.2 SEPP usage
Question 2:
What aspects of Water SEPPs does
your organisation currently use?
How could Water SEPPs be
improved to assist your
organisation’s day‐to‐day
operations and longer‐term
strategic planning?

As discussed in Section 4.1, there is a lack of clarity around how SRW as an organisation can meet the objectives
specific to them, and the actions taken in the event that they are not met.
The previous SEPP required additional work and ‘research’ to ascertain the actual target within the attainment
program it was required to comply with. SRW believe that the onus should be on the regulator to provide a
complete attainment program if applied to any organisation
SRW believe there are more significant gains to be made in terms of environmental benefits by targeting sources of
diffuse pollution
Groundwater
In regards to those roles and responsibilities outlined in Section 4.1, and broadly, SRW has the following points around
groundwater



Clarification is required around the term ‘potable’ as it infers that untreated water is drinking standard. The
Department of Health and Human Services and the water industry in general advise people should not drink
untreated water
Design requirements, setback distances and maintenance of septic systems are the responsibility of local
governments. Approvals are normally case by case without reference to cumulative effects. A database of sites
would greatly assist planning and management strategies.
Stormwater drainage that relies on direct or diffuse discharge to aquifers has normally avoided regulation because
it preceded the Water Act. Nevertheless there is no evidence of adverse consequences. For example in
Warrnambool where the aquifer is shared with urban usage the measured water quality has not declined. New
developments will need to comply with risk adverse regulation.
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4.3 SEPP (Waters)
Question 3:
Do you have any concerns about
the proposed working title of State
Environment Protection Policy
(Waters)? If so, what are they?
SRW is comfortable with the working title, SEPP (Waters). However, SRW note that the contents of the SEPP’s relating to
water is the critical component.
4.4 Feasible v
aspirational
SRW’s experiences have highlighted the SEPP (WoV) Schedule F5 produced an attainment program that was unfeasible as a
public investment in the context of the 10‐year lifespan of the policy. This has been quantified by an INFERR analysis,
detailed in Section 3.6 of this submission.
Question 4:
SRW believes that the following should be taken into consideration in regards to feasibility/aspirations of the policy;
What is the best way to reflect
what is feasible versus what is
aspirational in the context of a 10‐
year policy cycle?



Follow through on the discussion paper’s assertion that the policy will balance protection of water quality with
social and economic development i.e. a risk‐based approach to public investment
Having sound understanding of the aspirational goal and additionally an understanding of the time and investment
required to achieve it, which will help define feasible targets for the 10‐year lifespan of the policy
Applying a risk‐based approach to protecting beneficial uses to maximise potential improvements
4.5 Objective support
Question 5:
Do you support the proposed SEPP
(Waters) objective of “this policy is
to protect and improve the quality
of Victoria’s waters while providing
for economic and social
development”? Why?
SRW support the objective as stated.
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4.6 Socio/eco/enviro
balance
Question 6:
Do you support the need to balance
economic and social development
with overall protection and
improvement of water quality for
Victoria’s water environments?
Why?
SRW is supportive of this approach.
4.7 Trade offs
Question 7:
What are the challenges of
balancing economic and social
development with protecting and
improving water quality?
How should we manage the
appropriate trade‐offs between
them?
SRW are of the opinion that there should be flexibility in the way the SEPP deals with issues around balancing
environmental, social and economic issues. SRW supports the position taken in the VicWater response to the discussion
paper.
4.8 Uniform SEPP
Surface Water
Question 8:
SRW is comfortable with the proposed amalgamation of water SEPP’s but have some concerns with inconsistencies in
segment indicators (discussed below).
Do you foresee any problems or
opportunities that may arise from
creating one consistent SEPP to
apply to all Victorian waters? Are
there other options for streamlining
the policies that we should
consider?
Groundwater
There is some concern about how the segment indicators for groundwater will align with those for the surface waters that
potentially interact with groundwater, when the chemistry and salinity of these two very separate bodies may be
considerably different. The current interpretation of the existing SEPPS leads to decisions that don’t align with natural
processes (i.e. where a saltier aquifer discharges naturally to a waterway but that same groundwater cannot be used to fill a
recreational or ornamental lake in the same catchment).
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Surface Waters
4.9 Specific beneficial
uses
Question 9:
Are there any specific types of
water environments, for example, a
wastewater treatment lagoon,
where you think beneficial uses
should not be protected?

As within the current SEPP, SRW believe that beneficial uses do not require specific protection within irrigation
channels and drains, which should be managed for the purposes for which they were constructed. SRW has a vested
interest in providing water which is suitable for its customers and has ongoing obligations in regards to reducing the
impacts of water leaving drains on the beneficial uses of receiving waters.
Groundwater
 There would be benefit in the ability to excise some aquifers from some beneficial uses. For example the confined
sections of the Lower Tertiary aquifer may have water suitable for most purposes but GDEs and stock bores are
unlikely to be relevant at that depth.
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Surface Water
SRW strongly aligns with the VicWater response for questions 10 through to 13. In particular, SRW agrees with the need for
segments to contribute to a risk‐based approach as opposed to utilising them as a strict function for assigning obligations to
specific corporations, as was the case for SRW and the MID. Segments, sub‐segments and their associated management
must still recognise the multiple stakeholders and influences present in each system.
Groundwater
SRW believes there are flaws associated with the current method for classifying segments.
An aquifer based approach to policy could have some merit in the following instances:
4.10 Classification system
Question 10:
Do you think the current measures
for classifying surface water and
groundwater segments are still
appropriate? Are there other
measures that should be explored?






The example of aquifers being used for stormwater disposal with seemingly no adverse effect could be dealt with by
an aquifer definition which included disposal as a beneficial use of the aquifer. Perhaps there could be there a way
of dealing with these through stormwater management plans.
It is questionable that MAR or geosequestration for the purpose of storage is a beneficial use of water. Its purpose is
to use an aquifer structurally rather than the native water and the process displaces the native water. This is a
beneficial use of an aquifer.
It would be good to excise some aquifers from some beneficial uses. For example the confined sections of the Lower
Tertiary aquifer may have water suitable for most purposes but GDEs and stock bores are unlikely to be relevant at
that depth.
Desalination plants that dispose brine into aquifers have the potential to be a problem if the assumptions we make
about aquifers are wrong and there is a high density of plants in the one area. Perhaps we could define which
aquifers this is acceptable in and keep them out of others.
Irrigation districts unintentionally use aquifers for drainage. That is why groundwater control pumps are necessary
to manage high water tables. The irrigation drainage “freshens” the native groundwater and in porous aquifer
sections provides a great irrigation resource.
The relevance of certain beneficial uses at certain salinity ranges should be reviewed (i.e. what about brackish or
saline GDEs? Will animals actually drink water at the maximum salinity range for this beneficial use?)
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Surface Water
See response to 4.10.
Groundwater
4.11 Spatial arrangements
Question 11:
Are there any problems with the
spatial arrangements or segment
boundaries in the existing Water
SEPPs? If so, what are they?
SRW presents the following thoughts on the spatial arrangement for Groundwaters;




Generally the current arrangement works well because of its simplicity and clarity. An exception is in areas where a
beneficial use applies even though there is no practical use for the specified purpose or maybe no aquifer at all. The
EPA already has some discretion to make an evidence‐based decision to waive a beneficial use so has power to
manage this issue.
The number and salinity ranges of existing groundwater SEPPS should be reviewed as some segments are too large
to allow for changed water extraction and treatment technologies.
The current approach has significant limitations with data availability and density, as well as natural variation along
groundwater flow paths.
Alternatives to the spatial segment arrangement are discussed in Section 4.10 above.
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Surface Water
There is the potential for a lack of consistency in the application of segments and sub‐segments across the landscape. As an
example, the MID is noted in the discussion paper as a sub‐segment. However, SRW are aware of other key intensive
agricultural areas, such as Thorpdale and the Lindenow Valley. There needs to be some consistency in how segments and
sub‐segments are classified, and additionally flexibility built in to allow for adaptations over the lifespan of the SEPP.
4.12 Segments
Question 12:
What do you think are the
advantages or problems with the
new approach to segments and
sub‐segments?
There are both positives and potential issues associated with the classification of the irrigation district as a stand‐alone sub‐
segment;
ADVANTAGES;
 This method allows for the recognition of the MID (and areas that are of a similar nature in terms of water
management and use) as a highly modified landscape with unique water quality issues
 The definition, or exclusion, of beneficial uses for sub‐segments based on recognizing their inherent issues
 The definition, or exclusion, of objectives and indicators within a sub‐segment given the inherent issues with
applying such measures to a highly modified environment
DISADVANTAGES
 There is a concern that the classification of the MID (or any of SRW’s irrigation areas) as a sub‐segment suggests
that they may have associated beneficial uses and/or objectives and indicators within the sub‐segment. SRW
believe that if this were to happen it would be difficult to accurately assess impacts to both beneficial uses within
and outside of the sub‐segment. As such, SRW believes the focus should still be on minimising impacts to receiving
waters.
 The spatial mapping of the sub‐segment should be carefully considered, as many areas within the MID are actually
dryland farming and have different issues to those associated with irrigation. Additionally, the irrigation district is
undergoing consistent change. There is a risk that over the 10 year lifespan changes within the district will not be
able to be reflected in the policy, and as such flexibility needs to be built in.
Groundwater


The ability to classify sub‐segments for groundwater has not been taken into account and should be allowed as for
surface waters i.e. where human activities have a significant impact such as intensive agriculture areas or where
there is a high density of septic tanks
Groundwater SEPP segments should consider the impacts of current and historical land use, as well as those for
surface waters. The EPA GQRUZ program does not appropriately protect all potential resource users close to known
contaminated sites and in no way protects potential users in areas likely to be contaminated by historical practices.
What about significant agricultural areas?
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Surface Water
4.13 Stand‐alone segments As per the discussions held with the EPA during the SEPP review process, SRW and the West Gippsland CMA are of the
Question 13:
Are there any features of the
landscape that you would like to
see as a standalone segment or
sub‐segment?
4.14 Beneficial uses
Question 14:
Do you believe that all beneficial
uses set out in Table 2 of the
discussion paper should still be
protected under the new SEPP
(Waters)? Where do you think a
beneficial use would not apply?
Why?
opinion that the sub‐segmentation of the MID alone does not capture other key intensive agricultural areas in the
landscape, such as Thorpdale and the Lindenow Valley.
Groundwater
In line with the approach above, the same principles should be applied for groundwater management as are applied for
surface water. Further, in relation to our response to the previous question, areas of high septic tank density and high
likelihood of historic contamination from industrial sources should be considered.
Surface Water
SRW is comfortable with the current list of beneficial uses as presented in the discussion paper.
Groundwater
The following points should be considered;



Why are there slightly different beneficial uses for groundwater and surface water? They should be consistent.
Clarification is required around the term ‘potable’ as it infers that untreated water is drinking standard. In reality
the water industry and the Department of Health and Human Services advises people should not drink untreated
water.
It is suggested that potable mineral water is removed from the policy
4.15 Beneficial uses and
segments
Question 15:
SRW supports the VicWater response for Question 15.
What method or approach could be
used to apply the beneficial uses to
segments and sub‐segments?
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State Environment Protection Policy (Waters) Review 2015
4.16 Additional beneficial
uses
Surface Water
Question 16:
SRW supports the VicWater response for Question 16.
Are there any additional beneficial
uses that you believe should be
protected? Are there any that you
think should no longer be
protected? Why?
Groundwater
4.17 Indicators
Question 17:
What do you think about the
current indicators, the approach for
deriving objectives and the
proposed changes?
Southern Rural Water Submission
SRW believes the following should be considered;

Should aquaculture be listed as a beneficial use for groundwater?
Surface Water
SRW support the current indicators, and assume changes will align with national standards and the latest science
underpinning water management.
Groundwater
The current SEPP (GoV) objectives for the protection of beneficial uses are opaque. While it is important they are not so
specific as to require constant updating, they need to be significantly clearer in outlining the targets and indicators that
apply.
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SRW questions the use of targets that are not risk‐based, nor based on science. As highlighted with the MID target it is hard
to quantify the outcomes of investment based on targets where the targets themselves are difficult to quantify.
The discussion paper produced by DELWP states, amongst other notes, that the outcomes of the review should achieve;

4.18 Usefulness of targets
Question 18:
How have nutrient load targets
been useful in driving
environmental investment
outcomes? Would you like to see a
different approach, and if so, what
might that be?


Water quality objectives that align with the latest science underpinning water management and reflect changes to
the national guidelines, and;
Achievable short‐term targets that contribute to long‐term state‐wide objectives
An attainment program that makes it easier for industry and others to understand and comply with their obligations
Given the latest evidence presented within this submission, SRW believe that a nutrient reduction target does not fulfil the
first point above and as a result cannot fulfil the second or third points. It would therefore be a poor choice of regulatory
tool and present significant issues to the organisation deemed responsible for meeting a target (SRW or otherwise).
SRW and the West Gippsland CMA have recently agreed that a more suitable measure, and similarly a better driver of
investment, could focus on the uptake of Best Management Practices (BMP’s) on farms throughout the MID. As an example,
an attainment program could set a target of achieving a specified % of all farms under Whole Farm Plans in the MID by
2025.
Using uptake of BMP’s as a target has the following benefits;



Ensures direct investment and action at the pollution source
Has scientific backing (research shows that BMP’s are an effective way of reducing nutrients)
Provides a target whereby the baseline can be relatively easily obtained and measurement of progress is relatively
simple and tangible as compared with nutrient load targets
SRW also remains committed to its current program of nutrient monitoring.
4.18.1 Nutrient reduction
target – is it an
appropriate measure?
The current measure of progress in terms of nutrient reduction in from the MID into the Gippsland Lakes is the monitoring
and reporting of total nutrient loads, with the nominal target of 42 tonnes of Total P per annum stemming from the original
40% reduction target on a 70 tonne base load stipulated in Schedule F5 of the current SEPP (WoV). There has been a
number of references in the SEPP review process of the intention to set a new nutrient load reduction target for the MID.
Whilst the current SEPP requirements have been a driver for implementing change in the region, there are some major
flaws with the use of a nutrient reduction target as a statutory requirement in the SEPP. Given the above, and the
supporting evidence in Sections 2 and 3 of this submission, SRW does not support the use of a nutrient load target as an
appropriate measure for the upcoming SEPP (Waters).
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State Environment Protection Policy (Waters) Review 2015
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SRW does not agree with the use of nutrient reduction targets and believe there are better measures by which
environmental improvement can be facilitated in the upcoming SEPP. However, in the event that a reduction target was
selected as the preferred methodology, the following should be taken into consideration;

4.18.2 Nutrient reduction
target – how can it be
better




Any reduction target needs to have sound justification and evidence on what it will achieve in terms of
environmental outcomes and the protection of beneficial uses. The reasoning behind the ‘40%’ reduction target for
the current SEPP was poorly understood by all parties. The literature appears to refer to work that estimated a 40%
reduction to Lake Wellington would cause a shift in the Lake from a eutrophic to mesotrophic state (more
information in Section 2.3 of this submission).
Sound justification and evidence regarding the specified ‘baseline’ value if one is to be used
Flexibility to allow for external factors that influence nutrient loads, such as rainfall
The use of current understandings in the literature and the available datasets
Any target must have justification as to how it is achievable within the 10‐year lifespan of the SEPP (i.e. that it is not
overly aspirational). The INFERR Analysis detailed in Section 3.6.1 of this submission provides excellent context
about the achievability of load reduction targets
Importantly, SRW believes that if a nutrient reduction target is set it should be captured in a way that does not create a
situation whereby SRW could be held accountable for breaching a statutory requirement. This may be achieved through the
use of alternative arrangements, such as MOU’s or a requirement to work towards a target through the ongoing
implementation of an approved management strategy, such as the Macalister Land and Water Management Plan. This
ensures there will be continuing action within the district whilst removing excessive regulatory burden and potential
compliance issues.
4.18.3 What will nitrogen load
reduction target, and
monitoring, achieve?
SRW do not dispute the fact that nitrogen may have an impact on the health of the Gippsland Lakes, and that the Macalister
Irrigation District is one of many additional sources of the nutrient within the catchment. SRW also support the minimisation
of such sources in the pursuit of a healthier Lakes system. However, SRW does not believe that a nitrogen reduction target
and monitoring will help to achieve this end goal. The use of a measure that is highly dependent on external factors as a
regulatory tool does not address the issue, and in fact takes resources and effort away from where the significant changes
have occurred, and need to continue to occur; on the ground throughout the MID, and through current vehicles for change
such as the Macalister Land and Water Management Plan. It is in this capacity that SRW, and associated organisations such
as the West Gippsland CMA, are committed to ongoing support and action.
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State Environment Protection Policy (Waters) Review 2015
4.18.4 Implications of
monitoring additional
parameters
Southern Rural Water Submission
SRW has invested heavily, both in terms of time and money, in the ongoing management and monitoring of phosphorous
loads in the MID. Most recently, this included the review and replacement of the method by which nutrient loads are
estimated, including the installation of monitoring equipment and the development of a superior calculation method that
provides a more accurate picture of both the MID’s contribution and the inputs from outside the district. SRW are proud of
the contribution they have made in this space, and are committed to the continued implementation of the P monitoring
program.
It is important for the parties reviewing the SEPP to recognize the significance of incorporating an attainment program or
requirement for monitoring of additional parameters from the MID (or elsewhere) in the upcoming SEPP (Waters). Any
requirements, should the responsibility be delegated to SRW, represents a significant upfront and recurrent cost to the
business through the need to undertake additional research, develop new calculation models and cover laboratory
expenses. SRW therefore sees it as important that changes within the SEPP that may induce additional cost must have
sound justification, incorporate an assessment of the potential financial impacts, and be clear in how they will protect the
beneficial uses of the Gippsland Lakes or other defined at‐risk area.
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State Environment Protection Policy (Waters) Review 2015
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Surface Water
As previously iterated, SRW believes the development of specific management plans has proven to be an effective
mechanism for dealing with at‐risk areas, such as the Gippsland Lakes and the MID as a key contributor of diffuse pollution.
These plans allow the tackling of major issues in a coordinated approach, which is highly important for at‐risk areas that are
on a regional scale with multiple inputs, stakeholders and interests.
SRW is in support of the VicWater response to Question 18, and in particular the following characteristics of a framework
within the new SEPP;
4.19 At risk areas
Question 18:
What is the preferred method for
management of at‐risk areas? Are
there activities that need greater
intervention or regulation? What
would the intervention be, for
example, voluntary or mandatory
codes of practice, regulation via
licensing?











Clear objectives and targets that are linked to catchment‐wide outcomes
Linking priority segments and beneficial uses to clear triggers for intervention
Identifying and targeting the most significant sources of pollution in the catchment
Clear segregation between the policy/strategy setting role, implementing role and the regulatory role
Clear roles and responsibilities among all parties
Targeting lowest community cost solutions
Targeting interventions as close to the source as possible
Robust processes
Adequate resourcing
Maximizing interdisciplinary and cross‐agency cooperation
A robust evaluation framework tied to the objectives, targets and catchment‐wide outcomes.
SRW also strongly support emphasis being placed on actions that target the source of pollution, such as the EPA‐developed
Management of Dairy Effluent Guidelines. Such initiatives should be fully supported in the SEPP in preference to focussing
on licensed discharges or, in the case of the MID and similar areas, the designation of segments and associated attainment
programs.
Groundwater
The approach outlined above should also apply to groundwater with an additional provision to deal with historic and diffuse
contamination.
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4.20 Knowledge gaps
Question 20:
What do you think the role of SEPP
(Waters) should be in identifying
and filling knowledge gaps over the
life of the policy? How can we
assure an adaptive approach within
SEPP (Waters)?
Any other information you would
like to share:
SRW is of the opinion that the SEPP, for ease of use and clarity in regards to interpretation, should not play a specific role in
filling knowledge gaps. SRW has experienced first‐hand the difficulties associated with elements of the SEPP being non‐
specific; SRW was required under Schedule F5 to determine the baseline nutrient load for the MID for the purposes of then
reducing that baseline by 40% (more information on the issues associated with the Schedule F5 attainment program are
detailed in Sections 2.4.1 and 2.4.2 of this submission).
SRW again thanks DELWP (and the EPA) for producing the discussion paper and considering SRW’s submission. SRW is fully
supportive of the SEPP review and is willing to offer advice and expertise if and when required.
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State Environment Protection Policy (Waters) Review 2015
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5 References
Budahazy, M (2014)
Comments regarding the water savings attributable to modernisation works in the MID. 2014
Cook, P (2014)
Nutrients aint nutrients (commentary provided by Perran Cook to industry). 2014
CRC for Freshwater Ecology (Hart &
Cottingham)& Environment
Protection Authority (2000)
Environment Protection Authority
(2001)
Environment Protection Authority
(2000)
Nutrient Loads from the Macalister Irrigation District ‐ Report of Specialist Workshop held Monash University, 14 April,
2000
Fox, D.R (2003)
Analysis of Southern Rural Water’s Drain Monitoring Data. Centre for Environmental Applied Hydrology. 2003
Grayson, R (2006)
Prioritising nutrient reduction for the Gippsland Lakes and catchments – Part 1: Loads and Sources. Catchment to Sea Pty.
Ltd. 2006
Holland,D; Jennings, M; Beardall, J;
Gell, P; Doan, P; Mills, K; Briles, C;
Zawadzki, A and Cook, P; (2013)
Protocol for calculating Phosphorous Loads for the Macalister Irrigation District. EPA. 2001
Total Phosphorous Loads from the Agricultural Drains in the Macalister Irrigation District. EPA. 2000
Two hundred years of blue‐green algae blooms in the Gippsland Lakes. Gippsland Lakes Ministerial Advisory Committee.
Ladson, A (2012)
Importance of catchment‐sourced nitrogen loads as a factor in determining the health of the Gippsland Lakes. Gippsland
Lakes and Catchments Task Force.
Lowe, L; Sharpe, K; (2014)
MID Nutrient Method – Method and Model Development. Jacobs SKM (for Southern Rural Water).
Roberts, A; Pannell, D; Cottingham,
P; Doole, G; Vigiak, O; (2009)
Report on the Gippsland Lakes INFERR Analysis. Gippsland Lakes Task Force.
Webster, I; Parslow, J; Grayson, R;
Molloy, R; Andrewartha, J; Sakov, P;
Walker, S.J; Wallace, B (2001)
The Gippsland Lakes Environmental Study – Assessing Management Options for Improving Water Quality and Ecological
Function. CSIRO, DNRE, Gippsland Coastal Board, University of Melbourne. 2001
West Gippsland CMA (2008)
Macalister Land and Water Management Plan (Part A and B). 2008
Zhu, Y; Lee, R (2015)
Gippsland Lakes Modelling Scenarios. EPA and Monash University. 2015
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State Environment Protection Policy (Waters) Review 2015
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6 Attachment 1 ‐ SRW/WGCMA SEPP (WoV) Review Agreement
Purpose
Background
Current
obligations
What have
we done?
What have
we learnt?
The purpose of this paper is to summarise SRW and WGCMA’s position with respect to
the SEPP WoV review and in particular intensive agricultural areas in the Gippsland
Lakes’ catchment.
DELWP and the EPA are currently undertaking a review of State Environment Protection
Policies Waters of Victoria (SEPP WoV) and Groundwater of Victoria (SEPP GoV).
Since its original gazettal, a number of Schedules have been added to SEPP WoV.
Schedule F5 was created in 1996, focussing on the Latrobe, Thomson and Merriman
Catchments and the Gippsland Lakes.
SEPP WoV requires SRW, in cooperation with DNRE and land owners, to develop a
nutrient reduction plan by 1997. The plan is designed to reduce the annual load of
phosphorous from drains in the Macalister Irrigation District by 40% by 2005 (Refer
Clause 15.1, Schedule F5 of SEPP WoV).
SRW, WGCMA, DELWP, DEDJTR and the EPA along with local farmers and the (former)
GLMAC/GLTF have worked in partnership to reduce nutrient discharges from the MID to
the Gippsland Lakes:
 SRW in association with the DNRE, EPA and local farmers developed the
Macalister Irrigation District Nutrient Reduction Plan. The plan was lodged with
the EPA in November 1998 in fulfilment of Clause 15.1 of F5.
 The Plan sought to reduce phosphorus discharges by 40% i.e. from 70 to 42 tpa.
 The MIDNRP was reviewed and replaced by the Macalister Land and Water
Management Plan in 2007. The Plan is now administered by the WGCMA and is
due to be reviewed in 2016/7.
 The WGCMA and DEDJTR have been actively promoting on‐farm improvements
and the adoption of best management practices (BMP’s) through whole farm
planning.
 SRW has been modernising the district while continuing to maintain an ongoing
monitoring program.
 The agencies have established the Macalister Irrigation District Sustainability
Group (MIDSIG) to oversee the implementation of the MLWMP. It provides a
forum where knowledge and information can be shared between agencies,
thereby assisting with the identification of knowledge gaps and the prioritisation
of projects.
There has been considerable research into the quality of water in the Gippsland Lakes and
more particularly those factors that give rise to BGA blooms in the Lakes.
Attachment B summarises the key findings
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State Environment Protection Policy (Waters) Review 2015
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What do
1. SRW and WGCMA support the consolidation of SEPP WoV and SEPP GoV into a
single SEPP (Waters) from an efficiency perspective but note the real issue will be
we agree?
the contents of the new SEPP not simply the consolidation.
2. SRW and WGCMA support the inclusion of specific segment measures in the
SEPP.
3. SRW and WGCMA acknowledge that the Macalister Irrigation District is an
intensive source of nutrients and requires BMP’s to reduce the volume of
nutrients entering the Gippsland Lakes.
4. SRW and WGCMA suggest a nutrient management plan (e.g. ML&WMP) is still
needed to help reduce nutrient discharges and that such a plan needs to be
mindful of changing agricultural practices, along with SRW’s investment in the
modernisation of its infrastructure.
5. SRW and WGCMA suggest that the plan be expanded to include not just the
MID but the areas covered by SRW’s Macalister drainage network (i.e. the
Macalister Irrigation Area).
6. SRW and WGCMA suggest that the WGCMA is the most appropriate
organisation to prepare and administer the plan but in close consultation with
SRW, EPA, DELWP, other relevant government agencies and the local farming
community.
7. SRW and WGCMA suggests that other intensive agricultural areas be considered
for inclusion in the SEPP (such as Thorpdale and the Upper Latrobe catchment)
with the CMAs being the most appropriate organisation to prepare and
administer any plans but in close consultation with relevant government
agencies and the local farming community.
8. SRW and WGCMA support the discussion paper’s recommendation to include
‘water quality objectives that align with the latest science underpinning water
management’.
9. SRW and WGCMA submit that while the setting of targets provides a clear focus,
the setting of a nutrient reduction target (e.g. 40% reduction) is not appropriate
as:
 Despite considerable research an acceptable load level has not been
established.
 There are many factors outside our control.
 SRW’s own monitoring shows a high correlation between rainfall and load.
 The research suggests BMP’s are the most effective way of reducing
nutrients and hence the focus should be promoting BMPs in the district.
10. SRW and WGCMA suggest that a more effective target would relate to the
adoption of BMP’s which could be measured for example by the area of farms
under irrigation plans etc.
11. SRW remains committed to its current program of nutrient monitoring.
12. SRW and WGCMA remain committed to the Macalister Irrigation District
Sustainability Group as the primary agency forum for improving the
environmental performance of the MID.
13. Both SRW and WGCMA acknowledge that there has been significant success with
the governance and operational model developed in the MID through both the
strategic planning and implementation phases which in turn could be replicated
in adjacent sub segments of the catchment.
14. SRW and the WGCMA acknowledge the current knowledge gap relating to the
importance and role of Nitrogen loads exported from the MID on water quality in
the Gippsland Lakes.
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State Environment Protection Policy (Waters) Review 2015
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Attachment A
Macalister Irrigation Area
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State Environment Protection Policy (Waters) Review 2015
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Attachment B Key learnings
Water quality
Increases in catchment nutrient load will further worsen water quality in the
in the Lakes
Gippsland Lakes (Zhu & Lee 2015).
BGA triggers
Increases in catchment nutrient load will certainly increase the phosphorus
accumulation in the sediment and increase the severity of Nodularia blooms in
the long term (Zhu & Lee 2015).
Reduced catchment nitrogen and phosphorus loads may cause nitrogen limitation
for non‐N‐fixing phytoplankton but promote the growth of N‐fixing cyanobacteria
(Zhu & Lee 2015).
Nutrient
The focus of Nodularia blooms prevention must be on phosphorus reduction,
reduction
which includes both catchment input and sediment supply (Zhu & Lee 2015).
focus
MID
The MID contributes approximately 20% of the phosphorus load to the Gippsland
contribution
Lakes, i.e. 65tpa (Ladson & Tilleard 2006).
SRW’s own monitoring suggests that the estimate phosphorus load was between
23 tonnes (1996) and 90 tonnes in (2001), averaging around 52 tonnes per
annum.
Managers should be very cautious about the setting of absolute load reduction
Suitability of
targets due to uncertainty in load estimates and to the very high inter‐annual
targets
variability in loads (CSIRO 2001).
SRW’s own monitoring suggests that there is around a 70% correlation between
rainfall and load.
Relatively large (40%) reductions in MID loads correspond to only 10% and 3%
P reduction
reduction in western catchment TP and TN loads...these have environmental
efficiency
benefits which are proportionally small (Grayson et al 2001).
Even if the external loading is reduced, internal phosphorus loading from
sediment store may prevent improvements of water quality in the Gippsland
Lakes in the short term (Zhu & Lee 2015).
Even small decreases in nutrient load can benefit the Lakes…Small reductions in
nutrients lead to proportional decreases in chlorophyll concentration but
disproportionately large improvements in bottom oxygen (Cottingham 2006).
The greatest gains in terms of reducing nutrient loads to the Lakes will be
achieved by applying the most cost‐effective BMP’s to the sub‐catchments
contributing to the greatest proportional load (Cottingham et al 2006)
Current incentives for the dairy and dryland grazing industries could achieve a
13% P reduction (Roberts et al 2009).
Pursuing a 40% reduction in P would be difficult to justify on the basis of cost‐
effective public investment (Roberts et al 2009).
A 40% reduction in nutrient loads is not possible without new technology or
significant land use change in the catchment (Cottingham 2006).
With continued incentives and sustained effort at extension, BMPs are likely to
reduce P (Cottingham et al 2006).
N occurrence
Nitrogen does not tend to build up in the Lakes as most is rapidly de‐nitrified
(Ladson 2012).
N contribution Irrigation is estimated to contribute the most n/ha but covers a relatively small area,
so only contributes 7% of the total load to the Lakes (Ladson 2012).
There is a strong relationship (90% correlation) between annual N loads and annual
flow to the Lakes (Ladson 2012)
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