Conference Papers | 2005 Victorian Conference Papers
WATER'S EASTERN TREATMENT PLANT (ETP): "THE HACCP JOURNEY"
Melbourne Water Corporation
Melbourne Water obtained Quality Assurance (HACCP) certification
from Lloyd's Register Quality Assurance (LRQA) in March
2005. This paper presents the methodology undertaken
to deliver a certified HACCP Plan for one of Australia's
largest sewage treatment plants.
Key process steps and approach of the project are detailed,
including areas such as:
documentation development and integration into existing
the quality system and taking appropriate corrective
Recommendations for other organisations seeking HACCP
paper also describes the context for the HACCP plan
significance, in terms of strategic organisational goals
in water sustainability, recycling and customer relationship
CCP's, Quality, Risk Management, Class C, Class C2,
Water, owned by the Victorian Government, manages $8
billion of natural and built assets - Melbourne's water
supply catchments, most of Melbourne's sewage, rivers,
creeks and major drainage systems. Melbourne Water owns
and operates two major sewage treatment plants - the
Eastern Treatment Plant (ETP) and the Western Treatment
Plant - treating approximately 92% of Melbourne's sewage.
Retail water companies treat the remaining 8% at smaller
local sewage treatment plants.
a $1B asset servicing approximately 1.5 million people,
ETP treats approximately 40% of Melbourne's sewage (370ML/day),
using an activated sludge process, to a secondary standard
under an EPA Victoria Licence.
In preparation for a nutrient removal process upgrade,
to reduce effluent ammonia discharged via an ocean outfall,
ETP required an EPA Works Approval. A requirement of
the Works Approval was for Melbourne Water to deliver
a process stability plan. After considering stakeholder
requirements, the plan format chosen was a Hazard Analysis
and Critical Control Point (HACCP) system.
2.0 WHAT IS HACCP?
is a food based quality safety standard originally developed
by NASA to protect astronauts from Salmonella poisoning.
Widely adopted in the food and water industry, it is
now being used in wastewater as recycling opportunities
HACCP is a preventative risk management system for hazard
identification, assessment and management. Using semi-quantitative
methodology, it identifies risks and appropriate controls.
HACCP is based upon hazard source control and prevention,
rather than reliance on end point testing. This is achieved
through identification of 'Critical Control Points'
(CCP's) - specified limits that require corrective action
to ensure a compliant, fit for purpose product.
The system relies on appropriate procedures, monitoring,
validation of critical limits; documentation, performance
reporting and auditing to verify limits are being met.
The HACCP methodology comprises 5 steps and 7 principles,
and is represented in Figure
Figure 1: The HACCP Methodology
IMPLEMENTING A HACCP PLAN
was applied to ETP's two end products, Class C effluent
and Class C2 Biosolids, as defined by EPA Guidelines.
ETP must conform to these to ensure a compliant product
for current and future water and biosolid recycling
Detailed risk assessments identified CCP's in the treatment
process - five for recycled water, and one for biosolids.
Implementing the plan required a number of key steps,
some of which are described in greater detail in the
Forming the HACCP team
Cementing commitment in terms of key supporting resources
- Verification that targets are being met
additional system documentation
and formal plan Certification
The format used was to the LRQA specification, and incorporated
Management responsibility Product information (characteristics
and intended uses)
information (flow diagrams, layout)
measures (both specific to CCP's and general)
and critical limits
action (response to specification deviation)
('science behind the limit') and verification (audit,
addition, the ETP plan also incorporated key reference
documents, communication and consultation (stakeholder
identification), purchasing controls, and continuous
Developing the risk assessment is the heart of the plan.
It involved a number of workshops with a multi-disciplinary
team - internal and external representatives from appropriate
areas - planning, operations, asset managers and the
Retail Water Companies. Using a specifically developed
Process Flow Diagram (PFD), each process step from plant
inlet to the ocean outfall discharge point was assessed,
using a quantitative matrix (numeric scoring of likelihood
and severity) as per the AS4300 Risk Standard.
Risks were identified and ranked, producing a prioritised
list based on data, corporate expertise, scientific
validation and judgement. The process also identified
key focus areas for further investigation (such as specific
plant sampling and data analysis) to reduce or eliminate
risks. High/Very high risks underwent a secondary analysis
for risk mitigation, with those remaining high required
Decision Tree Analysis for CCP's and quality control
points (QCP's). A table was produced showing each process
step, its source, hazard and classification (physical,
biological or chemical), preventative and control measures,
likelihood (1-5), and severity (1-5) of occurrence (risk),
limiting hazard, downstream control measures and their
effectiveness, and a mitigated risk score.
For CCP's, appropriate record sources were listed.
measures include process operational strategies, manual,
online and laboratory monitoring, standard operating
procedures, maintenance regimes and reports, regulatory
and customer agreements, equipment redundancy, auditing,
and weekly operational meetings.
The hierarchy of controls for the plan are therefore:
Pre-requisite Programs (PRP's): These are the basic
requirements that are givens in a HACCP plan. They
include online monitoring, flow meters, adequate
maintenance systems, cleaning regimes, product specifications,
pest control and personal behaviour
Process steps with performance specifications, but
may fall outside ETP's direct control. Examples
include illegal raw sewage discharges and wet weather
CCP's: Following risk assessment, steps with high
residual risk may be deemed CCP's as measured by
a Codex Decision Tree analysis. Typically, this
is where engineering controls, on-line monitoring
and real-time management exists
3.3 Developing CCP's
Codex Decision Tree Analysis determines CCP's by asking:
Do control measures exist for the identified hazard?
the step specifically designed to reduce eliminate
the hazard to acceptable levels?
the hazards occur in excess of (or increase to) acceptable
Will subsequent steps eliminate the hazard or reduce
likely occurrence to acceptable levels?
risk assessment and Codex Decision Tree, determined
the six CCP's for the ETP:
Table 1: Eastern Treatment
Plant - HACCP Critical Control Points
the CCP's were established, ongoing verification is
required. This was achieved at ETP by the incorporation
of a Control Screen into the Process Control System.
A pictorial representation is shown in Figure 2. The
key screen features are trending of CCP data, warning
alarms as a CCP limit is approached, and at the limit,
a complete plant representation showing plant layout,
all CCP's and QCP's, and text help files detailing corrective
actions and incident response procedures for appropriate
This was supplemented with daily process engineering
verification of CCP's, feeding into weekly operational
meetings, and monthly management review of performance,
culminating in a Melbourne Water wide quality system
review across water and sewerage areas.
Figure 2: The ETP HACCP Control Screen
internal and interface audits were conducted. Internal
audits were structured as system or process audits.
System audits covered areas such as documentation, risk
assessment, management system framework, plan implementation,
operational controls (staff competency, process stability)
and maintenance controls. Process audits covered all
CCP's and QCP's, and interface audits such as Laboratory,
Maintenance and Cleaning Contractors. A pool of auditors
were trained in the HACCP system, and raised corrective
actions and observations for improvement. Once internal
auditing was complete, LRQA externally audited the system,
reporting results to Melbourne Water.
3.6 Additional Documentation
ensure that the plan integrated with current operations,
a number of additional documentation systems were required
to facilitate ongoing system performance. These included:
Audit register - tracking progress of audits, observations
and improvement notes
Process Control System data - an Excel based report
run periodically to verify CCP values, monitor the
number of and time duration of any exceedances, and
as a trending and management reporting tool to demonstrate
Action Reports (CAR's) - whenever a CCP alarm occurs,
a CAR is raised. This allows the HACCP coordinator
or others to verify either a genuine exceedance or
is a false positive result. In the event of an exceedance,
an incident report is raised and immediate corrective
action taken (which can include the plant ceasing
document register - each plan section has a list of
documents the reader can source for further information.
An electronic hyperlinked register also assists the
of a Hierarchy of Data register - ranking online equipment
data as high, medium or low criticality, in general
operational, HACCP or OH&S areas
- Several documents were required; overview training
for induction of staff and contractors, and a detailed
training module as part of skill matrix assessment
4.0 KEY CHALLENGES IN IMPLEMENTATION
Key challenges the plan presented to the HACCP team
Developing an entirely new QA system integrating seamlessly
with operations, compliance and environmental requirements
change to a food based safety standard product/resource,
not a "waste" product
operational shift from statistical compliance to ongoing
metrics to demonstrate ongoing compliance
relationship building (product recyclers and regulatory
5.0 IMPLEMENTATION OUTCOMES
Key outcomes delivered to the ETP were:
The system achieved external certification by LRQA,
within the projected time/budget
largest Australian wastewater treatment plant to achieve
development for staff across the business in HACCP
rigorous, scientific approach noted by external auditors
management in the value chain - from upstream supply
(raw material) to product (recyclers and general public)
rigorous risk management resulting in a robust, compliant
product that is fit for the intended uses as defined
by EPA Victoria Guidelines
Delivering an externally certified HACCP plan was an
innovative method of focusing on product quality, enhancing
opportunities for future effluent and biosolids recycling
opportunities, and facilitating mechanisms in the plant's
treatment systems for continuous improvement using new
and existing management systems.
The context of the ETP HACCP plan was of strategic significance
to a number of Melbourne Water's future corporate goals,
and integration with the aims of the Victorian Government's
White Paper on Water Sustainability.
Firstly, it provided contribution towards meeting the
recycled water target of 20% by 2010.
it interfaces with the Eastern Irrigation Scheme, a
water recycling project providing 5000 million litres
per year of Class A recycled water to a range of customers
via 50 kilometres of transfer and distribution pipelines.
Melbourne Water provides recycled water to its private
sector partner TopAq who undertakes further treatment
(using ultrafiltration membranes) to produce Class A
quality recycled water. TopAq then delivers the Class
A water to a number of users:
The Sandhurst Club residential development comprising
of 2000 homes and two 18-hole golf courses in Carrum
Downs was the first recycled water customer to be
connected under this scheme. It will ultimately use
1200 million litres of recycled water a year for the
golf courses and recreational areas, as well as for
residential use in gardens and toilet flushing.
water company South East Water will provide the recycled
water retail services to residential customers within
the project area.
Cranbourne-Five Ways area for irrigation of market
gardens, golf courses, a racetrack and for use through
a residential development dual pipe system for toilet
flushing and irrigation
a robust and compliant product places the ETP in a prime
position to enhance large scale recycling projects,
such as the two-year Eastern Recycling Scheme feasibility
study, which is currently examining the viability of
recycling 100,000 million litres of water to Latrobe
Valley power stations.
The approach taken built an extensive management system,
allowing ease of audit by LRQA, with the plan implemented
intimately linked with regulatory compliance, building
efficiency in approach for both systems.
For organisations seeking to develop a certified HACCP
plan, it is recommended that the following aspects be
There are many ways to construct a HACCP plan. An
appropriate methodology needs to be chosen to facilitate
ease of audit by an external or third party
implementation commitment early in the project. Identify
project champions, auditors, training, HACCP team
members, and key internal/external resources
is critical to document all risk assessment process
aspects. Typical detail includes quantitative scoring
rationale, workshop minutes and evidence of appropriate
multi-disciplined approach is taken. Involve operational,
engineering, planning, asset managers, managerial
personnel and appropriate external stakeholders
validation of all critical limits - set up electronic
based systems for ease of CCP validation, re-validation
periodically and ongoing performance verification
all plan changes are approved and validated by the
HACCP team - the system must be dynamic to function
documentation - hardcopy filing and electronic file
tree systems increase efficiency of verification of
plan accuracy during audit
documentation that interconnects with existing systems.
Additional operational layers are not as efficient
as integration. Examples included for the ETP: Structuring
audit checklists format similar to it's Water group
HACCP and Environmental Management System (for auditor
synergy and familiarity across the business), electronic
hyperlinks for audit reports, and linking CCP's to
Finally, it is important to emphasise that obtaining
system certification marks only the start of a journey
along a continuous improvement path. Melbourne Water
will be undertaking six monthly external surveillance
auditing to ensure that the implemented system continues
to function. This includes intensive aspects of monitoring
and reporting to facilitate ongoing HACCP compliant
The author acknowledges the excellent support and assistance
provided by the HACCP Team members Ron Lourensz (Team
Leader Pump Station and Sewerage Treatment Plants),
Stephen Cahill (ETP Shift Team Leader). The support
of project champions - John Woodland (a/General Manager
Operations), and Robert Jenkins (a/Manager ETP), external
stakeholders, auditors from the Eastern and Western
Treatment Plants and staff members across multiple business
groups greatly assisted the successful implementation
of the HACCP system at ETP.
Eastern Treatment Plant HACCP Plan v1.0 - Wise
S. (February 2005)
RvA Requirements for a HACCP Specification (Version
3) - National Board of Experts - HACCP. The Netherlands