2016-07-12 - Item 14 - Att 1 - Effluent Disposal Planning Study

Section 2

© Noosa Council 2016

www.noosa.qld.gov.au

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Endorsed by Noosa Council [date to be inserted] or insert document date

Section 3

Table of Contents
1.    Executive Summary ............................................................................................................. 2
2.    Introduction .......................................................................................................................... 3
      2.1         Preparing for the 1997 Strategic Plan ....................................................................... 3
      2.2         Previous Planning Study 1997 ................................................................................. 3
      2.3         Planning Scheme Review ........................................................................................ 5
3.    About On-site Wastewater Treatment ................................................................................ 6
      3.1         Overview .................................................................................................................. 6
      3.2         Types of Systems..................................................................................................... 7
      3.3         Environmental Impacts ............................................................................................. 8
4.    Policy Context .................................................................................................................... 11
      4.1         Queensland Legislation .......................................................................................... 11
      4.2         Review of Queensland Legislation ......................................................................... 13
      4.3         Review of Queensland Legislation – Discussion Paper, June 2014........................ 13
      4.4         Noosa Council ........................................................................................................ 14
5.    On-site Wastewater Treatment in Noosa Shire ................................................................ 17
      5.1         The Noosa Plan ..................................................................................................... 17
      5.2         Managing On-site Wastewater Treatment Systems in Noosa Shire...................... 188
      5.3         Noosa Council On-Site Domestic Wastewater Treatment Plant Audit Program .... 199
6.    Future Policy Direction for Noosa Shire ........................................................................ 222
7.    Recommendations for the new Noosa Planning Scheme ............................................. 244
8.    References ....................................................................................................................... 255




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Section 4

1. Executive Summary
Our developed world offers a variety of lifestyles and places to live, work and play. Always though,
lying in the background is a vital system of pipes and plant that deal with our liquid wastes. In our
urbanised places the collection and disposal of liquid effluent is on an industrial scale with a
sophisticated network of pipes, pump stations and advanced treatment plants. For other places
such as smaller settlements and rural situations, domestic effluent is predominantly disposed of
on-site.

We have these systems because our generated liquid wastes can be harmful to human health and
to the environment. Human illnesses associated with failed on-site treatment can be caused by E.
coli, Giardia, Hepatitis A, Cryptosporidium and salmonellae.

Noosa Shire is no different in respect to liquid waste and has features typical to regional Australia
with a mix of sewerage systems and on-site disposal. Several towns and settlements are
unsewered with on-site disposal methods utilised, as is also the case in all rural localities. The key
aspects of on-site disposal are a holding tank, a treatment process and the release of treated liquid
to the ground at surface or sub-ground levels. The released liquid can have differing levels of
contaminants depending on the system. The receiving environment is also variable such that the
cumulative impacts of released waters from a multiplicity of systems can have the potential to
cause deleterious effects on local ecosystems including waterways. The system installed should
best reflect the needs of the individual circumstances.

The installation and management of an on-site waste water treatment system is regulated by
Queensland legislation (Plumbing and Drainage Act 2002) and implemented by Noosa Council. A
substantial study of on-site wastewater treatment in Noosa Shire was undertaken in 1995-97 as
part of the background investigations that lead to the Noosa Shire Strategic Plan 1997. With a new
Planning Scheme proposed by Noosa Council, it is timely to again consider the circumstances of
on-site disposal. Technological improvements have taken place since the mid 1990s and this
study considers whether there are any implications for managing development in unsewered
localities.

This study concludes that while there have been advances in the technology available with
treatment systems, they generally require a degree of management by the homeowner to deliver
the predicted standards of the effluent discharged. That standard of management is variable in
practice, lessening the average standard of discharge and the reliance that can be placed on such
systems in vulnerable circumstances. Where there are potential risks to human health and
environmental values, caution is warranted. In addition, the Queensland Government is currently
investigating options that will lead to an improvement in the operation of existing on-site systems.
What is also highlighted herein is the universal lack of comprehensive testing and research into the
travel of discharge across and below the varied types of receiving environments.




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2. Introduction
2.1        Preparing for the 1997 Strategic Plan
In 1995 Noosa Council was preparing a new Strategic Plan, a statutory plan under the Local
Government (Planning and Environment) Act 1980. Strategic Plans undertook long term
considerations leading to guidance on land use and other forms of development and were a
component of the Council’s Town Planning Scheme. Key features of a Strategic Plan were maps
showing preferred dominant land uses and written material expressing objectives and
implementation provisions.

As a prelude to preparing the 1997 Strategic Plan Council commissioned a series of planning
studies that collected and analysed bio-physical data. The studies were assisted by a range of
state and local policy inputs. Relevant background to informing the Strategic Plan included:-
           Flood risk
           Vegetation types and values
           Slope and landslip risk
           Bushfire occurrence
           Soil types
           Geology
           Agriculture
           Climate
           Catchments
           Landscape Networks
           Waterways

In the mid 1990’s the population of Noosa Shire was expanding and was passing 30,000. Tourists
added to that number. Concerns about the pace of growth and the apparent inevitability of
development and its impacts on the local environment, were evident in the community and within
Council. This resulted in a close examination of the suitability of land for future development and
the capacity of infrastructure networks.


2.2        Previous Planning Study 1997
A Planning Study On-site Effluent Disposal & Water Quality in Noosa Shire was completed in
February 1997. The project had two aims: –

       1. To assess the suitability of the Shire’s land for on-site disposal of effluent, based on a
          strategic mapping assessment and the maintenance of water quality within the Shire’s
          waterways; and
       2. To develop guidelines for on-site effluent disposal consistent with the findings of the
          mapping assessment.

The study focused on the two principal types of on-site disposal, absorption trenches and domestic
treatment plants. The study also drew upon other investigations of land use, geology/soils,
topography/slope, vegetation and flooding. Three types of guidelines were requested: –

       1. Densities of allotments appropriate to varying land classes
       2. The design and layout of allotments and associated house site areas
       3. Soils testing criteria.

Peter Edmiston of Bio-track undertook the study and a draft of his report was reviewed by several
technical staff of Council. Noosa Council endorsed the project’s findings in March 1997 and the
finalised Planning Study was publicly released.

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The study found there was a large body of water quality sampling results, but that the absence of a
methodology behind collection and testing prevented any useful interpretation of long term
changes in water quality. With ‘little information’ for much of the shire, a conservative approach
was adopted. Recommendations about future water testing of key areas were included. (P.8)

A further significant challenge arose in the resolution of ‘acceptable’ run-off quality – defined in the
study as ‘sustainable, conservative and practical’. This is broad terminology and does not offer
specific parameters for determining preferred actual outputs for differing terrain.

The Shire was divided into 8 catchments (refer Figure 1). Run-off from these catchments was
modelled using a daily time-step water balance for a number of defined land uses for each
catchment. Estimates of runoff (with an allocated nutrient export rate) were performed for each
catchment. Separate studies referred to above were important inputs to support this work.
Predicted water quality accounted for residential use together with various rural uses existing in the
catchments.

The modelling results suggested Lake Macdonald, Maroochy and Stumers catchments already had
more dwellings than was desirable. Lake Weyba was close to a recommended maximum. Kin
Kin, Mary River East and Lake Weyba had a reliance on off-site dilution to achieve suitable stream
water quality. The remaining catchments Cooroibah and Mary River West exhibited sustainability
of water quality. (P.3&4)




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Section 7

Figure 1 - Division into Catchments




2.3      Planning Scheme Review
The Noosa Plan 2006 has a horizon year of 2015. While it has been amended a few times it is due
for comprehensive review and replacement. The 2006 plan was prepared under the Integrated
Planning Act. That act was replaced by the Sustainable Planning Act 2009. New legislation
(Planning Act 2016) was assented to in May 2016.

Council has commenced work on a new Planning Scheme for Noosa Shire. This planning study is
intended to assist Council when considering development potential in unsewered areas.




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Section 8

3. About On-site Wastewater Treatment
3.1      Overview
Figure 2 (courtesy Building Codes Queensland) is a simple representation of the main elements of on-site
wastewater treatment.

Figure 2 - On-site wastewater treatment




The following overview is an extract from a Discussion Paper to support a review of the Plumbing
and Drainage Act 2002 prepared by Building Codes Queensland and released in June 2014.

        The non-sewered areas of Queensland are most commonly serviced by septic tanks or on-
        site sewage treatment plants. The resulting effluent is either treated and diverted for re-use
        (greywater only) or applied to land application areas.

        The function of an on-site sewage treatment plant is to receive and to treat domestic
        sewage by means of aerobic and/or anaerobic processes and, where required, disinfection
        so as to produce an effluent appropriate to the land application area.

        An on-site sewage treatment plant must protect public health by minimising the risks
        associated with the treatment of sewage and its ultimate discharge to the environment.
        On-site sewage facilities that are appropriately designed, sited and maintained can provide
        satisfactory waste management solutions. However, anecdotal reports suggest that many
        systems are underperforming (60 – 80%) and, as a result, pose an increased risk to public
        and environmental health.

        Environmental impacts caused by the discharge of poorly treated sewage may include
        pollution of groundwater, streams and waterways along with degradation of soil and
        vegetation. Apart from the environmental effects caused by poorly or untreated wastewater,
        failing systems also pose a health risk through direct human contact. This can not only lead
        to upset stomachs, they can also lead to more serious conditions caused by bacteria and
        viruses. Children are particularly at risk when they play in areas that are polluted by the
        discharge from poorly serviced or maintained on-site sewerage [sic] treatment plants.
        Failing on-site sewerage systems can have the following adverse impacts to both the
        occupants of the property and public in general:
                  spread of infectious bacteria, viruses and other organisms in the wastewater
                  cause odours

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                  attract pests (mosquitoes, flies and rodents)
                  contribute to the pollution of groundwater, streams and waterways
                  cause degradation of soil and vegetation.

       Owners/occupiers play a crucial role in ensuring that on-site sewage treatment plants are
       regularly maintained and that the system continues to effectively treat the waste water. The
       failure of on-site sewerage systems is generally attributed to one of three factors:
                operation of the system (loading rates, mechanical malfunctions, pump failure)
                maintenance (lack of regular servicing, maintenance and testing)
                siting and design issues (soil types, subsurface water entering system during
                   flooding events)


3.2        Types of Systems
In Queensland the two most common types of on-site wastewater treatment systems are: –
           Primary systems - septic systems where biological processes treat waste which is
            subsequently discharged below ground
           Secondary systems - on-site plant employing mechanical, biological and filtration
            processes to treat waste with discharge either above or below ground.
For legislative purposes the secondary systems are classified into subgroups of secondary quality,
advanced secondary and advanced secondary with nutrient removal. All secondary systems
require the prior approval of the Queensland government before they can be released to the
market. Each system must be accompanied by manufacturer’s specifications, with compliance
with the specifications being a condition of approval for installation.

Figure 3 - Sand Filtration System




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Section 10

The government, as at April 2016, had approved many systems. Secondary -35, advanced
secondary - 25 and advanced secondary with nutrient removal - 7.

For this Planning Study, the above systems are of primary interest. The use of holding tanks,
common collection systems, greywater treatment or chemical, composting, incinerating or
waterless toilets are not considered due to their lesser potential for adverse impacts.

Figure 4 - Aerated treatment plant




3.3      Environmental Impacts
The primary purpose of on-site wastewater treatment is to enable the safe use of land for housing
and other purposes in circumstances where there is no sewerage for collection of unwanted liquid
wastes. Those liquids entering the treatment system primarily contain contaminants of nitrogen,
phosphorus and faecal coliforms. Both nitrogen and phosphorus are potentially adverse to the
receiving environment being nutrients. Faecal coliforms are dangerous to human health.

On-site wastewater treatment is an effective means of dealing with these potentially hazardous
wastes provided the conditions are suitable. Inappropriate discharging is unfortunately far more
common than would be desirable. Given the range of factors that can impact on satisfactory
operations, including occurrence of adverse weather conditions, it is not the case that all systems
can be made to work all the time.

Understanding the potential impacts of the systems on the receiving environment is a complex and
evolving issue. Treatment systems can be audited and an understanding of their failings is
currently possible. However, the effects of failing systems on receiving environments are another
matter entirely. Studies and the technical understanding of these impacts are limited and
potentially quite varied depending on the local circumstances of soil, weather, terrain and
vegetation.

Various studies have been published following investigations around Australia. These mainly relate
to assessing areas which are predominantly employing septic tanks. This planning study does not
propose an overview of those efforts. What is clear though is that there is a variety of findings and
conclusions in attempting to determine the general suitability of on-site treatment systems. More
research and sampling will contribute to an improvement to a technical understanding of the issue.
Modelling capability is also progressing as demonstrated by some initiatives in south east
Queensland that are attempting to predict water quality processes throughout an entire catchment.

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It is plain that on-site wastewater treatment systems will be in use for a long time into the future. A
principal objective for regulating bodies should be to encourage the satisfactory operation of
installed systems in all except obviously adverse circumstances (for example, flooding and
extended power failures) A secondary objective should be to support further studies into the
external effects of these systems.

Figure 5 - Sub-surface irrigation system




Figure 6 - Mulched land application area associated with surface irrigation




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  The Great Barrier Reef is widely acknowledged as suffering adverse effects from differing
  causes that include land-based activities. Marine and coastal ecosystems can be damaged by
  poor water quality associated with sediment, nitrogen, phosphorus and pesticides from rural
  and urban sources, coastal development, marine activities and most significantly, climate
  change.

  This has led to the Australian government and Queensland government endorsing a Reef
  Water Quality Protection Plan in 2003 and its update in 2009 and 2013. This plan sets targets
  for improved water quality and actions to improve that quality particularly through land
  management practices. The Australian government has funded six regional plans to assist in
  achieving the desired outcome for the Great Barrier Reef. Of interest here is the Water Quality
  Improvement Plan for the Burnet Mary Region which includes the Mary Basin. This plan was
  prepared by the Burnett Mary Regional Group and consultants Natural Decisions.

  The Mary Basin at 930,000 ha is the second largest catchment within the Burnet Mary Region
  and poses the greatest risk within the region to coral reefs and seagrass through degraded
  water quality arising from sediment, nitrogen and phosphorus. Just over half of the catchment
  is used for grazing and it has the highest population and greatest area of urban land uses
  including the towns of Maryborough and Hervey Bay. The Water Quality Improvement Plan
  proposes three delivery mechanisms in the form of incentives (stewardship payments), skills
  development for landholders and further research. One of the research priorities is to
  “improve understanding of catchment hydrological processes and relationship between land
  management practices and water quality”.

  On-site effluent disposal systems are not highlighted in the Water Quality Improvement Plan.
  The main attention is to broad hectare grazing and the more significant urban settlements.
  However the concerns expressed about the Mary Basin’s adverse contributions to the health
  of the Great Barrier Reef and the expressed priority for further research into understanding
  catchment hydrological processes lend some small weight to the policy positions
  recommended in this planning study.




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Section 13

4. Policy Context
4.1        Queensland Legislation
The design, approval, installation and management of on-site wastewater treatment systems are
primarily the responsibility of the Queensland government. The Plumbing and Drainage Act 2002
sets out the legislative framework. The Act is supported by the Standard Plumbing and Drainage
Regulation 2003 and the Queensland Plumbing and Wastewater Code. The Act regulates the
plumbing and drainage industry and the management of on-site sewerage facilities. Its objectives
relate to protecting the environment, public health and safety. Provisions within the Act cover:–

           Plumbing and drainage functions performed by the Queensland Building and
            Construction Board and the Commissioner of the Queensland Building and
            Construction Commission
           Audit programs
           Licensing of plumbers and drainers
           Disciplinary actions
           Assessing plans
           Chief Executive approvals (relating to on-site sewage treatment or greywater treatment
            plants not exceeding 20 persons)
           Investigation and enforcement by Local Governments

The Act provides for the technical standards for plumbing and drainage to be set out in a
regulation. The 2003 Regulation specifies the requirements for plumbing work and drainage work
to be undertaken by licensed persons. The regulation sets out the qualifications and practical
experience required for a licence and scope of work. The regulation also provides that on-site
sewerage work must comply with the Queensland Plumbing and Wastewater Code which includes
that the installed wastewater plant be maintained in accordance with the manufacturer’s
specifications.

The Queensland Plumbing and Wastewater Code describes performance solutions to meet the
statutory requirements of the Act. The Code has a tabular format with columns for Performance
Criteria and the relevant Acceptable Solutions. Under the Code, on-site wastewater systems must
be designed, constructed, installed and maintained in such a manner as to –

       a) protect public health by ensuring that risks associated with the dispersal of wastewater
          to the land application area are minimised; and
       b) protect the environment by ensuring-
             i.   surface and ground water are not polluted;
            ii.   soil productivity is maintained or enhanced; and
       c) minimise the impacts on and maintain and enhance amenity by ensuring it has no
          adverse impact on-
             i.   the built environment, and
            ii.   persons on and nearby the premises,
          for the design life of the facility.

There are obligations on property owners and service agents. The property owner must take
reasonable steps to properly maintain the on-site wastewater system. Service agents must provide
Council and the property owner with a report on the condition of the system within a month of
servicing it.

The Queensland Government also issues information bulletins about plumbing related matters and
on 4 November 2014 issued Building and Plumbing Newsflash 534 - On-site sewerage facility
requirements. This newsflash sets out a basic overview of how to obtain the necessary approvals



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Section 14

for on-site wastewater treatment systems. The material is intended to assist understanding of the
regulations by the general public.

Figure 7 - Extracts from Chief Executive Officer approvals




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Section 15

4.2        Review of Queensland Legislation
On 15 June 2014 the Queensland Government released a discussion paper and held information
sessions in regard to a review of the Plumbing and Drainage Act. The consultation period ended
on 25 July 2014.

The review focused on:

           streamlining requirements to reduce the regulatory burden on industry, without
            compromising public health and safety, and
           reducing red tape, time delays and associated costs for housing providers, plumbing
            licensees, local governments and homeowners.

The government has considered feedback from the review and is currently finalising its response
with a new Act anticipated before the end of 2016.


4.3        Review of Queensland Legislation – Discussion Paper, June 2014
The Discussion Paper ‘Review of the Plumbing and Drainage Act 2002’ contained suggestions by
the Queensland government for improvements to the regulation of plumbing and drainage work.
On-site sewage treatment plants and Chief Executive approvals were specifically addressed.
Section 4.1 is informative to current circumstances of on-site treatment. It contains clear
statements of concern over gaps and shortcomings in the operation and management of installed
systems, particularly secondary treatment. The following extracts from the discussion paper are
important to this Planning Study.

       With increasing awareness about the impacts and consequences of poorly performing
       systems there is a growing concern from local governments about how to manage these
       systems. The current standards are also coming under scrutiny as to whether they can
       ensure adequate treatment performance.

       Local governments are currently obliged to maintain service information (recordkeeping
       only) for on-site sewage facilities and greywater facilities. They have advised that these
       notifications are simply stored and don’t offer any value.

       Also, many maintenance providers do not supply the required service certificates which
       leaves local governments in the position of following up a document they place limited
       value on. These issues result in significant cost and administrative burden on local
       governments.

       It has also been identified that there are gaps in the legislation covering the recording,
       inspection, auditing and monitoring of the systems. As the current regime is not mandated,
       local governments are reluctant to charge a fee for service and they have competing
       demands and limited financial resources. The resource burden for inspecting these
       systems can be considerable as they are often placed in geographically diverse locations.
       This often results in local governments not having the trained resources to monitor these
       activities and they generally only inspect properties following a complaint.

       On-site sewage facilities that are appropriately designed, sited and maintained can provide
       satisfactory waste management solutions. However, anecdotal reports suggest that many
       systems are underperforming (between 60 and 80%) and, as a result, pose an increased
       risk to public and environmental health.

In response to the several concerns set out above the Discussion Paper proposes four potential
improvements to the regulatory framework:-


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       1. Service persons required to only provide notification to local government on failed
          systems
       2. Impose minimum testing requirements for on-site sewerage systems – Local
          Government to inspect/audit/monitor
       3. Local government providing reports to provide for data analysis of on-site systems and
          greywater systems
       4. Undertake a comprehensive review of on-site sewage systems

In support of improvement 4 above, it was further explained that such a review is in part warranted
by a lack of relevant scientific data or supporting analysis of the performance of on-site systems. In
consequence anecdotal evidence is the best available. The review as proposed is intended to
deliver a standardised framework and undertake an evaluation of the current methods for testing
and approving systems. The following areas for investigation were nominated:-

           A thorough examination of the evidence to determine the potential causes of failure of
            the systems.
           Whether the current testing standards adequately represent the conditions that the
            system will be exposed to when installed and whether this is responsible for the failure
            of the system.
           Considering provisions that permit the cancellation of approvals where it is found that a
            particular type of system has failure rates beyond acceptable standards.
           How innovative systems are approved where there is no specific testing process.
           Investigating options to improve Australian Standards to remove the need for
            Queensland specific testing standards.

For Chief Executive approvals, the discussion paper proposed the assessments could be
undertaken by accredited bodies.


4.4        Noosa Council
Plumbing responsibilities of Noosa Council are dealt with by Building and Plumbing Services. This
Branch performs all functions required by the Plumbing and Drainage Act 2002. The Branch
employs several licensed and experienced plumbers to perform these roles.

Noosa Council also performs town planning functions and The Noosa Plan 2006 zones all
properties for various land uses including residential, rural residential and rural. The Noosa Plan
also sets the standards for subdivision of allotments.




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Section 17

Figure 8 - Example of zoning within the Noosa Plan




Subdivision of land is addressed under Division 23 Reconfiguring a Lot Code which establishes the
allowable allotment sizes and specifies many other detailed requirements. An overall outcome of
the code is that allotments will avoid significant adverse effects on the natural environment and
landscape and minimise the risk of hazards for people and property.

The table below is an extract from the Reconfiguring a Lot Code and sets out the minimum
allotment sizes for the residential zones of Detached Housing and Semi - attached Housing.




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In Cooroy, where there is sewerage available, the minimum allotment size can be 800 m².
Pomona and Cooran have a minimum allotment size of 2000 m² which can be reduced to 1000 m²
if a connection to sewerage reticulation is available. That reduction will only apply to Pomona as
Cooran will remain unsewered due to Unitywater having no plans to install it. Boreen Point and Kin
Kin have a minimum allotment size of 2000 m². The small settlement of Cooroibah is set at 1000
m². Cooroibah is sewered and in any event has no further potential for subdivision.

With Cooran having no prospects of sewerage being installed, the future minimum allotment size in
the next planning scheme could be specified at 2000 m².




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Section 19

5. On-site Wastewater Treatment in Noosa
   Shire
Figure 9 is a map of Noosa Shire. At 85,000 ha it is comprised of mostly rural areas with urban
development in a scattering of towns and villages and also in coastal communities from Tewantin
to Peregian Beach. Approximately 35% of Noosa Shire has a tenure that protects environmental
values.

Figure 9 - Noosa Shire




5.1        The Noosa Plan
The Noosa Plan 2006 includes all land in zones for the purpose of applying particular development
regulations. The zones have land use descriptors and those zones of particular interest to this
study are as follows: –

           Rural - applied to broad rural holdings
           Rural Settlement - for rural land subdivided into lots of an average around 1 ha intended
            for rural homesite purposes
           Detached Housing - for individual house sites in urban areas
           Village Mix – commercial centres in the towns and villages.

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Within the Rural and Rural Residential Zones there are over 6,000 privately owned properties
ranging in size from under 1 hectare to over 80 hectares. Houses are or can be built on these
properties. Extensive urban areas are zoned Detached Housing but it is the unsewered towns and
villages that are of relevance to this study. In Cooran, Kin Kin and Boreen Point there are
hundreds more privately owned properties that rely on onsite effluent disposal for houses and other
forms of development.

Unitywater has principal authority to plan future sewerage networks. Cooroy is fully sewered.
Most of Pomona is included in a current sewer connection scheme. The balance of the town’s
developable land is nominated by Unitywater as a future sewer connection area. Sewerage is not
found elsewhere outside of the coastal communities, except for the rural residential estate of Swift
Park at Cooroy and the settlements of Cooroibah and Noosa Banks, north-west of Tewantin.
Along with all the rural areas, Cooran, Kin Kin and Boreen Point are also without sewerage.
Unitywater has no endorsed plans to take sewerage to any of these towns.

In terms of future development potential outside sewered areas:-

            Future development opportunities in the unsewered areas amount to a few small
             pockets remaining in Cooran,
            Land included in the Rural Zone in almost all instances cannot be further subdivided,
             and
            No new areas of Rural Settlement land can be planned due to restrictions in the SEQ
             Regional Plan. There may be some limited subdivision potential in these rural
             settlement areas.

Planning Scheme Policy #24 – Effluent Disposal gives guidance to applications for development
that require the installation of on-site wastewater treatment systems.

The purpose of this Policy is to—

         a) ensure that where development is not served by reticulated sewage infrastructure,
            there is no adverse impact on ground and surface water quality, human health and
            amenity as a consequence of the on-site disposal of effluent;
         b) ensure that land use decisions favour the protection of ground and surface water
            quality where there is doubt regarding the likely impacts of on-site disposal of effluent;
            and
         c) provide guidance to the public, developers and Council staff to assist in assessing
            development applications.

Each effluent disposal system is required to be sited —

        a) at least 15m from any potable water supply tank;
        b) above the 1% AEP (1:100 ARI) flood level; and
        c) more than 40m horizontally from the level of the Highest Astronomical Tide (HAT)
(The Qld Plumbing & Wastewater Code in Table T5 also specifies setbacks to dwellings & recreation areas at 10m,
property boundaries and paths at 2m and swimming pools at 6m.)


5.2         Managing On-site Wastewater Treatment Systems in Noosa Shire
Council’s Building and Plumbing Branch has authority for oversight of on-site wastewater treatment
systems. They receive applications, undertake assessments, grant approvals, inspect premises
and maintain records. These responsibilities also cover conducting audits and responding to
individual site issues whether arising from audits, complaints or unsatisfactory maintenance
reports.


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Section 21

Figure 10 - A secondary treatment system serving a small dwelling




5.3        Noosa Council On-Site Domestic Wastewater Treatment Plant Audit
           Program
In October 2014, Council endorsed a program to conduct a formal audit of wastewater facilities in
Noosa Shire. At that time there were 3109 septic installations, 2161 secondary or advanced
secondary systems and a further 86 properties relying on holding tanks.

Consequently Council received approximately 8000 service reports from contractors and conducts
an average of 100 inspections annually. Normal audit practices involved a desk top study of
service reports submitted by contractors and to investigate issues as identified.

The principal aims of the endorsed audit program are to –

       1. Allow Council and system owners to identify potentially failing systems, and
       2. Audit service reports to test accuracy.

The program has provision for up to 50 detailed analysis tests to be submitted to a NATA approved
laboratory. The program will additionally test new software applications and equipment.
The audit reviews domestic on-site wastewater treatment plants and their land disposal systems.
The focus of the program is on Secondary, Advanced Secondary and Advanced Secondary
systems with Nutrient Reduction.

Council inspectors assess the land disposal system and the treatment plant for faults and record
the results on a report loaded onto a mobile app. The app records the sludge level, total
suspended solids (TSS), PH and dissolved chlorine content of the treated effluent. Comments on
the land disposal system are added to the app. There is provision for testing which will involve
sending samples to a NATA approved laboratory to check for levels of nutrients and thermo-
tolerant coliforms.

A review of 100 audit results demonstrated 41 systems were found to be not compliant.
Test results showed:-

           9 plants had total suspended solids levels greater than the permitted range,
           4 plants had PH levels out of the recommended range,
           8 plants required pump outs due to high sludge levels,

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          6 plants had insufficient chlorine levels, and
          7 mechanical faults were found. ( broken air blowers, pumps and alarm systems)

For land application areas 16 were defective. The issues were overgrown vegetation and
inappropriate ground coverage, signs not being in place and faulty sprinklers. There was no record
of failures to subsurface irrigation although anecdotal instance and past complaints suggest that
failures are common over the life of the system (15 years).

There was one treatment plant which had a sand filter that had completely failed and needed
replacement.

Audit Conclusions
The audit reveals there are extensive faults with on-site waste water treatment plants and their
land disposal systems. The issues vary in seriousness and most faults can be prevented or fixed if
the correct servicing procedures are adhered to and proper maintenance of systems is carried out.
Some owners and renters of properties do not maintain their treatment plants properly. During
trials to obtain a Chief Executive approval the influent into treatment plants is meant to be within
certain parameters to ensure the system is working at its optimal level. The influent from private
households is not always within the correct parameters. Products such as bleach, dishwashing
liquid, hair dyes and certain medications can have a negative impact on bacterial growth within the
plant. Overloading from high water usage or over population of dwellings can also have a
detrimental effect on the systems.

Faults regarding surface irrigation are usually minor and can be rectified at minimal cost but if there
are faults with subsurface irrigation it can be costly and hard to fix. High total suspended solid
levels are a major cause of the failure. (It is rare to find a system that disposes of treated effluent
from treatment plants into trench systems.)

Faults regarding the treatment plants can be costly and hard to fix depending on the system.
Pumps and blowers (blowers are in aerated treatment plants) have a lifespan and will eventually
fail. Overworking of pumps from blocked land application areas or high work rates due to high
flows into the treatment facility are some common reasons for failure. Sand filter systems can get
blocked and are very costly to repair. High suspended solid levels is the main reason for failure
and this can occur when systems are not pumped out when the sludge levels are high or an
overloading of the system occurs (eg. too many people residing in the residence, greater than 10
equivalent people)

Causes
          Residents and owners of properties are not aware of the maintenance requirements for
           treatment plants,
          Owners of properties are under financial pressure and are not able to fix problems with
           treatment plants,
          Service agents are not servicing the treatment plants properly or are under pressure
           from owners due to owners not having enough money to fix problems, and
          Some systems are not favourable for certain areas and require a different approach to
           future systems in such areas.

Solutions
        Acknowledge new plumbing legislation is likely in 2016 and prepare to respond as
          necessary,
        Consult with industry to discuss requirements and possible solutions to issues,
        Continue with on-going audit program to monitor treatment plants and use the
          opportunity to inform owners of the risks and their obligations,
        Provide information to the Queensland government on the performance of treatment
          plants to assist in policy development,
        Implement local policies to try to improve the situation and reduce current risks, and


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Section 23

          Development applications should be accompanied by a rigorous site and soil evaluation
           to better advise the type of system necessary where the soil conditions are marginal, as
           well as preferred building envelopes and lot sizes, in the case of subdivision proposals.




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Section 24

6. Future Policy Direction for Noosa Shire
Reference has been made to a previous Planning Study On-Site Effluent Disposal & Water Quality
in Noosa Shire 1997. The context of the study remains relevant today.

            Noosa Shire is located within a sensitive but rapidly growing part of coastal
            Queensland. A significant proportion of future development within the Shire will
            be located in areas where reticulated sewerage systems are unlikely to be
            developed. On-site wastewater treatment and disposal is an important town
            planning, health and environmental issue.
            Future planning aims for sustainable development. It is important to incorporate
            wastewater treatment and disposal within town planning guidelines at an early
            stage to avoid costly errors. Listed below are a number of important issues
            relating to domestic wastewater disposal.
                    1. Water quality must be maintained at its present standard as the
                        minimum acceptable water quality.
                    2. Significant areas of the Shire are devoted to National Parks and
                        nature reserves that must be maintained in pristine condition.
                    3. The Shire has an extensive system of rivers and lakes with extended
                        residence periods. These systems are considered sensitive to
                        increases in nutrient loading.
                    4. The Shire is dependent upon tourism for a significant portion of its
                        revenue and this industry will be threatened by a deterioration in
                        environmental standards. This particularly applies to ecotourism,
                        fishing and other aquatic recreation.
                    5. The Shire has undergone a rapid increase in population in the
                        hinterland region where there is no provision of reticulated wastewater
                        collection. Significant expansion of the existing wastewater collection
                        system into these areas is not considered likely due to the very high
                        cost of infrastructure development and maintenance.
                    6. The Shire will be faced with increased demands for housing as the
                        population of South East Queensland rises.
                    7. Whilst a large body of water quality information exists for the Shire,
                        the data has largely been collected on an ad hoc basis with little
                        uniformity in collection or testing methodology. It is difficult to use this
                        data to infer long term changes in water quality.
                    8. Knowledge of the response of local streams and lakes systems to
                        nutrient, pathogen and sediment loadings is rudimentary and largely
                        based upon inference from other Australian or overseas studies.
                    9. The rainfall/run-off behaviour is highly variable and water quality
                        factors (stream flow, depth, light transmission, sediment load, nutrient
                        load, dissolved oxygen, etc) are likely to change by an order of
                        magnitude during different periods of any one year.
                    10. It is considered difficult, expensive and time consuming to undertake
                        remedial activities in most catchments or water bodies to correct
                        mistakes that occur. In particular, permitting urban development to
                        proceed in areas where reticulated wastewater collection is
                        impractical, will result in increases in nutrient export that are extremely
                        difficult (if not impossible) to control.
                    11. Should dwellings be permitted in any area it is almost impossible to
                        remove them. Urban development is considered essentially an
                        irreversible process that has highly variable effects on the general
                        environment.




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Section 25

In light of the above, the previous Planning Study concluded a conservative approach towards
development in unsewered locations is justified until further information emerges. The information
gaps identified in 1997 are still largely present today. Additional water quality testing has occurred
but there is still no more certain understanding of the likely environmental effects of on-site
wastewater treatment systems in Noosa Shire along with other regions. Our countryside is varied
with differing slopes, geology and soil characteristics. The movement of sediment and pollutants
across ground can be estimated but in the absence of extensive local monitoring, predictions are
best guesses at this time. The situation is similar for sub-surface movement but estimation is an
even less certain process. It is therefore difficult to accurately quantify the effects of sediment and
pollutants on the environment within a broad catchment. The amount of pollutants and sediment
present in waterways can be tested but as to estimating how and what caused it is a much more
difficult matter. There have been recommendations for more research to be supported in the
documents supporting this planning study.

Technology and the options for on-site wastewater treatment systems have progressed
significantly since 1997. A wide range of secondary treatment systems have emerged and been
brought to the market. Due to the improved outcomes anticipated, these systems have been
popular. However widespread shortcomings have evolved with the ongoing operation of the
systems. The Queensland government is currently investigating measures to improve on the
operational aspects of secondary treatment systems. Tertiary systems have a better reputation but
due to their extraordinary costs currently, very few are installed in Noosa Shire.

Improvements in the technology are acknowledged but the shortcomings around maintenance do
not yet convincingly offer any degree of confidence that secondary treatment systems can be
safely employed in marginal locations.

The following specific policy positions are recommended for endorsement by Council: –

       1. Catchment wide environmental effects of on-site wastewater treatment systems are not
          well understood. Further research into these effects is supported in principle in
          conjunction with a water quality monitoring framework.
       2. Secondary level on-site wastewater treatment systems have the capability to work well
          locally. However there is widespread failure associated with the maintenance of the
          systems. Positive action including audits and community engagement, is necessary for
          improving the outcomes for secondary systems. These measures to be considered
          when the current plumbing legislation is reviewed.
       3. In respect to future development in unsewered localities, a precautionary approach be
          adopted.
       4. Notwithstanding 3 above, development in unsewered localities that complies with the
          intent of the applicable zone of The Noosa Plan is assessed in the normal manner, but
          with greater consideration to the operation of the approved on-site wastewater
          treatment plant.
       5. For Cooran the 2000 m2 minimum allotment size remains apropriate, noting that
          sewerage is not planned to be provided.




On-Site Effluent Disposal in Noosa Shire 2016                                                  Page 23

Section 26

7. Recommendations for the new Noosa
   Planning Scheme
The preceding chapters have highlighted the current circumstances of on-site effluent disposal
across Noosa Shire. Traditional primary systems involving a septic tank are declining in use when
landowners are considering available options. Most new development is employing secondary
level systems. However concerns have been identified with the operation of secondary systems.
The effects of these failures on the environment are not well understood and this is unsatisfactory.

Policy measures to improve this situation are recommended in Chapter 5 and 6. In addition the
Queensland government is likely to introduce new plumbing legislation in the later part of 2016 that
will bring a stronger enforcement of compliance with the manufacturer’s specifications for
secondary treatment systems.

There are many vacant and under-developed allotments in the unsewered localities of Noosa
Shire. Most of these are intended for a dwelling house with others intended for alternate forms of
development. The recommended policy position in Chapter 5 is to allow for development to
continue where it is in accordance with the intent of the zone under The Noosa Plan. However
greater attention is recommended towards the operation of the approved treatment system.

Recommendations for the new Noosa Planning Scheme

       1. A precautionary approach is applied to proposals for more intensive activities that rely
          on on-site wastewater treatment disposal. The desired outcome in The Noosa Plan to
          avoid significant adverse effects on the natural environment and landscape and
          minimise the risk of hazards for people and property remains current but is not being
          delivered by a significant proportion of installations using secondary treatments.

       2. This Planning Study also supports the continuation of the limited potential for further
          subdivision of rural and rural residential land and for further subdivision of residential
          land in unsewered township localities.




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Section 27

8. References
      On-Site Effluent Disposal & Water Quality in Noosa Shire – Noosa Council, February 1997
      Plumbing & Drainage Act 2002
      Review of the Plumbing and Drainage Act 2002 Discussion Paper – Building Codes
       Queensland, June 2014
      Queensland Plumbing and Wastewater Code – Building Codes Queensland
      B&P Newsflash 534
      The Noosa Plan 2006
      Planning Scheme Policy – Effluent Disposal, February 2006
      Water Quality Improvement Plan for the Burnett Mary Region 2015 – Burnett Mary
       Regional Group and Natural Decisions
      Are On-site Systems Environmentally Sustainable? E Gardner, A Vieritz and C Beal, On-
       site ’05 Conference, Armidale, September 2005




On-Site Effluent Disposal in Noosa Shire 2016                                          Page 25