Chapter 2
Preventing Beach Pollution
Sources of bacterial contamination
The sources of pollution in waters
monitored by Beachwatch are varied. Water
quality is affected by a combination of
human activities and environmental factors.
Factors such as rainfall, catchment
characteristics, tidal flushing rate, sunshine
(UV radiation) and surf dynamics can
significantly alter bacterial levels between
sites.
Effect of rainfall
Rainfall has an important effect on flow
conditions in sewerage systems and
stormwater drains, although each beach has
a different response depending on the
catchment area, the extent and stage of
development, and the condition of the
sewerage system.
In general, faecal contamination increases
with rainfall, but some beaches appear to
reach a rainfall threshold above which faecal
contamination rises rapidly (for example,
Woolwich Baths), while others exhibit an
apparent log-linear response (for example,
Warilla Beach). Others appear to be largely
unaffected by rainfall (for example, Box
Beach).
Stormwater
High rainfall increases the flow in the drains
and transports stormwater runoff into the
receiving waters. This runoff contains
pollutants from both non-specific catchment
sources (urban runoff) as well as sewer
overflows and sewer exfiltration. Urban
runoff generally contains the artificial or
natural compounds found in, or derived
from, the catchment.
Visual stormwater pollution is an element of
urban runoff and is a combination of street
litter and organic matter that has
accumulated in the catchment and is flushed
into the receiving waters during rain.
Substances frequently transported in urban
stormwater runoff include:
• silt and organic or inorganic suspended
particles
• sewage from overflows and leakages in
the sewerage system
• animal faecal waste (for example, dog
droppings)
• oils, greases and surfactants from
roadways and industrial and domestic
sites
• plant fertilisers, pesticides and chemicals
from building sites and gardens
• litter (including rubbish and leaf litter,
grass clippings and twigs).
The amount of runoff is determined by
factors such as geology, topography and the
proportion of impervious surfaces in a
catchment. The constituents of runoff are
generally related to the type and density of
development in the catchment. Runoff is
typified by large volumes of fast-flowing
turbid water entering drains within minutes
of a rain event and eventually draining into
the local creeks, rivers and harbours and on
to beaches.
Sewage treatment plants
Sydney cliff-face sewage outfalls
Warriewood STP and Cronulla STP are the
only two remaining coastal sewage
treatment plants that discharge sewage from
cliff-face outfalls in the Sydney region.
Warriewood STP, located on the northern
beaches, discharges sewage treated to a
secondary level with disinfection from
Turimetta Head.
Cronulla STP discharges sewage treated to a
tertiary level with ultraviolet disinfection at
Potter Point, on the Kurnell Peninsula. Prior to
April 2001, Cronulla STP discharged primary
treated sewage and was a major source of
pollution affecting Cronulla beaches.
In addition to the discharges from the two
coastal STPs, sewage from Watsons Bay,
Preventing Beach Pollution
9
Vaucluse, Diamond Bay, Rose Bay North
and parts of Dover Heights is discharged
untreated to the Tasman Sea from three cliff
face outfalls at Vaucluse, Diamond Bay and
Diamond Bay South. The volume of
untreated sewage discharged is
approximately 3.6 million litres per day, or
0.3% of Sydney’s sewage (Sydney Water
2002 and 2003).
Sydney deepwater ocean outfalls
Results presented in previous Beachwatch
season reports have indicated that Sydney’s
ocean beach water quality has vastly
improved since the commissioning of the
deepwater ocean sewage outfalls in the early
1990s. The deepwater ocean outfall system
was designed to improve dilution and divert
sewage from the cliff-face outfalls,
transporting primary-treated sewage from
Sydney’s STPs at North Head, Bondi and
Malabar to the outfall points two to four
kilometres out to sea at a depth of 60 to 80
metres.
Since the commissioning of the deepwater
ocean outfall system, visible sewage
indicators and bacterial levels at Sydney’s
northern and city ocean beaches have been
dramatically lowered (Beachwatch 1995,
1996 and NSW Environment Protection
Authority 1996). Elevated levels of bacterial
indicators are still detected at some beaches
after intense rainfall, owing to the impacts of
stormwater, sewage overflows and STP
bypasses.
Hunter region sewage treatment plants
Hunter Water operates 17 sewage treatment
plants in the Hunter region, with three
ocean outfall plants located at Boulder Bay,
Burwood Beach, and Belmont.
Illawarra region sewage treatment plants
Sydney Water operates five coastal sewage
treatment plants in the Illawarra, located at
Bellambi, Wollongong, Port Kembla,
Shellharbour and Bombo. The GerringongGerroa STP is operated by Vivendi Water
under a 20-year design, build and operate
contract.
Sewage overflows
Sewage overflows can be a major source of
pollution, especially within estuarine and
10
enclosed waterways. Overflows can be
caused by rainwater entering the sewer
system and increasing the pressure within
the system.
Sewage overflows occur at designated
points in the sewer system when the
hydraulic capacity of the system is
exceeded. These designed points direct
excess wastewater into natural watercourses
and stormwater drains, limiting
uncontrolled surcharges on to private
properties.
Sewage overflows may also occur from
sewage pumping stations (SPSs). While
much of the sewerage system is gravity-fed,
SPSs are used in areas where sewage must
be pumped up slopes or across flat areas.
SPSs can overflow when their hydraulic
capacities are exceeded in wet weather, or
when there is a loss of power or a
mechanical malfunction. Sewage exfiltration
may occur from cracked pipes or via
openings in the pipe network as a result of
roots accessing the pipes. Tree roots or
blockages from debris in the sewerage
system may cause chokes, which may result
in overflows.
An estimated 3000 designed overflow points
exist within Sydney’s sewer systems, of
which 200 contribute approximately 80% of
the total discharge volume (Sydney Water
2002).
The worst sewage overflows in Sydney are
located in Middle Harbour and the Lane
Cove River in Sydney Harbour and the
Cooks River area of Botany Bay. To
compound this problem, flushing rates in
these areas are slow, and it may take days
before bacterial contamination falls to
acceptable levels. The time taken for these
waterways to recover to acceptable levels is
influenced by the quality of the water in the
local tidal region and the proximity of the
site to clean oceanic waters.
Sewage treatment plant bypasses
Bypasses from STPs occur when the sewage
stream is diverted, either untreated or partly
treated, from the plant directly into a river,
estuary or ocean. This can cause local beach
pollution.
State of the Beaches 2003–2004
Bypasses may occur in dry weather, owing
to problems such as a mechanical fault at the
plant, or in wet weather, when the capacity
of the plant is exceeded by large volumes of
stormwater in the sewer system.
Notifications of bypasses were received in
2003–2004 for Warriewood STP, Cronulla
STP and all Illawarra coastal STPs, with the
exception of Gerroa. The majority of
bypasses were related to wet weather. Dry
weather bypasses due to equipment failure
occurred at Cronulla STP in August 2003
and January 2004, and at Warriewood STP
in October 2003 and January 2004.
Preventing beach pollution
Many things are being done to prevent
pollution at the beach. State and local
government are successfully tackling
sources of beach pollution in a range of
different ways. Many non-government and
community groups are also making a
significant contribution to pollution
prevention.
Actions to improve the quality of stormwater
Phase II of the NSW Government’s Urban
Stormwater Program is well underway. This
follows the success of the first, three-year
phase (1997–2000), which was funded by
$60-million allocated to the Stormwater
Trust. The primary aim of Phase I of the
Program was to encourage and support
better stormwater management practices to
improve the condition of the State’s urban
waterways.
The key elements in Phase I were:
• A Stormwater Trust Grants Scheme,
which allocated $51 million primarily to
local councils to undertake 252
stormwater projects throughout the State.
These projects included the piloting of
innovative technologies to improve
stormwater quality, remediation actions
and the use of non-structural stormwater
management techniques.
• A state-wide Urban Stormwater
Education Program (USEP), which aimed
to promote community awareness,
knowledge and understanding of the
extent and causes of stormwater
problems and facilitate behavioural
change by promoting simple, practical
ways for particular groups and
individuals in the community to reduce
stormwater pollution. USEP integrated a
range of intervention strategies including
mass media, community and school
education, vocational training and a
variety of partnership projects in key
sectors.
• A Stormwater Management Planning
process whereby local government were
required to prepare stormwater
management plans (SMPs) for urban
areas. The plans were prepared jointly on
a catchment basis. As part of this process,
Sydney Water and Hunter Water were
directed by the EPA to produce
Stormwater Environment Improvement
Programs (SEIPs) that documented and
prioritised all actions identified in the
SMPs relating to their assets.
Following a favourable independent
evaluation of Phase I of the Program, an
additional $22 million dollars has been
made available to fund Phase II of the
Program.
The key elements of Phase II of the Urban
Stormwater Program include:
• funding of stormwater projects
undertaken by local councils through
Stage 4 of the Stormwater Trust Grants
Scheme
• continuation of the Urban Stormwater
Education Program
• the appointment of nine Stormwater
Extension Officers to guide, assist and
coordinate councils in their management
of urban stormwater. These officers are
hosted by regional organisations of
councils.
• an investigation, together with the
Department of Local Government, into
sustainable funding arrangements for
urban stormwater management in NSW
• audits of local councils’ progress in
implementing SMPs
• a series of ‘capacity building’ projects,
aimed at improving the ability of local
councils to manage stormwater in an
environmentally responsible and costeffective manner
Preventing Beach Pollution
11
• funding of nine ‘Strategic Grants’ to local
councils to develop and document ‘best
practice’ in relation to aspects of local
council operations that affect stormwater
management.
Actions to upgrade Sydney’s cliff-face sewage outfalls
The State Government’s upgrade of the
Cronulla STP was opened on 24 April 2001.
The upgrade involved the addition of
secondary biological treatment, tertiary sand
filtration, ultraviolet disinfection and
chlorination for recycled water. The
treatment scheme allows for recycling of the
treated wastewater by local industry,
thereby reducing the volume of discharge
from the plant. There has also been an
increase in the capacity of the plant (Sydney
Water 2001).
Pipelines have also been constructed under
Port Hacking to connect residents of
Bundeena and Maianbar to the Cronulla
STP. These areas have historically relied on
on-site systems such as septic tanks.
Sydney Water carried out community and
stakeholder consultation, between 2001 and
2003, to identify a potential solution to the
untreated sewage outfalls at Vaucluse and
Diamond Bay. The outcomes of the
consultation are currently being reviewed.
Sydney Water will undertake an
environmental impact assessment (EIA)
following a decision on the preferred
strategy.
Upgrades to North Head, Bondi and Malabar ocean
outfall STPs
In 2001 Sydney Water completed upgrades
to the raw sewage pumps at North Head
STP to improve the reliability of the plant.
Works have now commenced to modernise
older parts of Bondi STP to ensure reliable
performance and minimise the risk of plant
failure and bypass. These works will also
improve the safety of staff working at the
plant. The project is scheduled for
completion in 2007 (Sydney Water 2004c).
Around $2 million has been spent annually
on projects to improve the reliability of
Malabar STP. These projects have included
ongoing maintenance and replacement of
12
existing equipment and installation of
duplicate equipment.
In 2002, Sydney Water completed a $15million facility at Malabar STP to produce
around 90 dry tonnes of high quality
biosolids per day for agricultural use
(Sydney Water 2002).
Actions to upgrade Hunter region sewage treatment
and transport systems
Over the period from the mid 1980s to the
late 1990s, Hunter Water has focused on
improving the performance of the ocean
outfall plants. Secondary biological
treatment was introduced at Burwood
Beach, Boulder Bay and Belmont STPs. An
extended ocean outfall was also constructed
at each of the plants.
Stockton STP served approximately 5000
people and, until its decommissioning in
July 2002, was the last remaining Hunter
plant to discharge primary treated effluent
through a shoreline outfall. Wastewater
from Stockton has been transferred to the
newly upgraded Shortland STP (Hunter
Water 2002).
Strategies to address wet weather issues and
cater for growth for the next 20 years have
been identified through the development of
Upgrade Management Plans for the Lake
Macquarie and Newcastle areas. These plans
include works to increase the capacity of the
sewerage system (upgrades to SPSs, pipes
and provision of storage to cater for heavy
rainfall events), and works to reduce the
amount of rainfall entering the system
(sealing access chambers, relining of
pipework and smoke testing to locate illegal
stormwater connections) (Hunter Water
2003a).
Upgrades to sewerage systems in Swansea
and Booragul were completed in late 2002 at
a cost of almost $3.5 million. This involved
upgrades to eight SPSs (including
installation of new pumps, electrical
equipment and mains at the Booragul
station), construction of 3.1 kilometres of
new mains and relining of 2.9 kilometres of
sewer pipes. This work has reduced sewer
overflow problems in these areas (Hunter
Water 2003b).
State of the Beaches 2003–2004
The next stage of works, due for completion
in late 2005 and costing $21.4 million, will
double the capacity of the wastewater
system in the Warners Bay, Valentine and
Belmont areas. Works include upgrades to
six SPSs, sewer mains and the Belmont STP
(Hunter Water 2003a).
treatment processes and modifications to the
ocean outfall to improve dispersion of
effluent (Sydney Water 2004d). The
Environmental Impact Assessment is
complete and works are scheduled to begin
in late 2004, finishing in early 2006.
The preparation and staging of Upgrade
Management Plans for other catchments,
including the coastal and Port Stephens
Catchments, are being considered.
The Gerringong-Gerroa sewerage scheme
was initiated to provide sewerage services to
the townships of Gerringong and Gerroa,
areas previously relying on on-site
wastewater systems. The scheme was
completed in August 2002, and more than
75% of households have connected to the
system so far. The project included the
construction of a sewage treatment plant at
Gerroa that utilises advanced wastewater
treatment technology. More than 90% of
effluent is reused on neighbouring
agricultural properties (Sydney Water
2004e).
Hunter Water has also initiated a
community awareness program to promote
the use of ‘sewer pipe friendly’ trees and
reduce the number of sewer chokes caused
by tree roots.
Actions to upgrade the Illawarra region sewage
treatment and transport systems
Under the Illawarra Wastewater Strategy,
dry weather flows from the Bellambi and
Port Kembla STPs will be diverted to an
upgraded and amplified Wollongong STP.
A new one-kilometre ocean outfall will also
be constructed at Wollongong STP to replace
the existing short ocean outfall. Bellambi
and Port Kembla STPs will be converted to
specialised storm flow plants that will store
and treat wastewater during extended
rainfall events.
A new water recycling plant is also being
constructed at Wollongong STP that will
produce at least 20 million litres of almostdrinkable treated effluent each day. An
agreement has been reached with BlueScope
Steel to use treated effluent at the steelworks
near Wollongong STP.
The above works commenced in May 2002.
The transfer pipelines, upgrade of
Wollongong STP and extended ocean outfall
are expected to be finished towards the end
of 2004, and work on the storm flow plants
should be complete by mid-2005 (Butow
2004).
Other components of the Illawarra
Wastewater Strategy include the
amplification of the Shellharbour STP to
meet the demands of population growth
within the Albion Park and Shellharbour
areas up to 2025. Works include
construction of additional tanks to allow for
increased flows, improvements in sewage
Gerringong-Gerroa Sewerage Scheme
Actions to reduce sewer overflows – SewerFix
Sydney Water is required under EPA licence
conditions to fix leaky sewers, upgrade
sewage pumping stations and improve the
overall maintenance of the system.
SewerFix is Sydney Water’s 20-year
program for maintaining and improving the
sewer system. Key work completed
includes:
• Construction of the Northside Storage
Tunnel to capture wet weather overflows
from the four major overflow sites at Lane
Cove, Quakers Hat Bay, Tunks Park and
Scotts Creek. The Tunnel was designed to
reduce the number of overflows at the
four major wet weather overflow points
from more than 150 to less than 20 in an
average 10-year period. Since coming online the Tunnel has prevented more than
12 billion litres of diluted sewage from
entering Sydney Harbour (Sydney Water
2004a). The Tunnel stores and transports
these overflows to the North Head
Sewage Treatment Plant (STP) for
treatment, before discharge via the deep
ocean outfall.
• Lining and grouting of 360 kilometres of
sewer mains has been completed to date,
resulting in a 17% reduction in wet
weather overflows in areas where both
Preventing Beach Pollution
13
Sydney Water and private sewers have
been rehabilitated (Sydney Water 2004b).
• 1535 kilometres of sewer mains have been
cleaned, reducing the choke rate per 100
kilometres of sewer from 82 in 2000–2001
to 74 in 2002–2003. A further 1000 km of
sewer mains are being cleared of chokes
each year (Sydney Water 2004b).
• Upgrades have been completed to 206
SPSs to minimise the risk of dry weather
sewage overflows, with telemetry
systems installed in 333 SPSs to reduce
the response time to SPS failures and
improve management of the stations
(Sydney Water 2004b).
• $12 million was spent on amplifying the
sewerage system in the Chatswood area
to allow for population growth. This
work was completed in September 2003
and will reduce the potential for dry
weather overflows (Sydney Water 2004b).
• Silt removal works have been carried out
over the last three years on the Southern
and Western Suburbs Ocean Outfall
Sewers (SWSOOS) in the Botany area.
These works will continue over the next
year. Cleaning and internal structural
repairs will also be carried out on the
SWSOOS in the areas of Matraville,
Botany and Rockdale over the next three
years.
Partnership Pilot with Local Councils
Fifteen coastal councils in NSW participated
in the Beachwatch Partnership Pilot
Program during summer 2002–2003, with
seven councils continuing their involvement
in 2003–2004. The two and a half-year
program aimed to increase the consistency
and quality of recreational water quality
monitoring and reporting undertaken along
the NSW coast. Details of the program are
provided in the case study at the beginning
of this report.
Environment and community groups and associations
A great range of commercial and non-profit
groups are also doing their bit to tackle
stormwater pollution. These include council
14
and commercially funded environment
centres, volunteer groups, and stormwater
and wastewater associations.
These groups are working closely with local
business, industry and government agencies
on cooperative projects to improve
stormwater quality and eliminate pollution,
as well as developing ‘leading edge’
technology and approaches to stormwater
management and pollution control. They
also play an important role in community
education on water pollution issues.
You, your friends and family
To help protect your local beach and
waterway, there are plenty of community
groups to join:
• Contact Streamwatch to find out if there
is a group linked to your local school.
• Get involved in local activities sponsored
by Clean Up Australia.
• Call your local council to find out about
Bushcare activities in your local area.
• Join a local conservation group, such as
Dunecare, Landcare or Coastcare, or the
Australian Trust for Conservation
Volunteers.
Further information can be accessed from
the Marine and Coastal Community
Network (www.ozemail.com.au/~mccnet).
The Network promotes information sharing
among community groups, government
agencies and industry.
You can make a difference at the beach:
• Take litter and leftovers home with you.
• Park cars carefully, preferably on a hard
surface to avoid damaging grass verges or
coastal vegetation.
• Keep beach showers to a minimum.
The community can help prevent beach
pollution in lots of ways. Table 1 lists ways
in which you can help to improve
stormwater quality and Table 2 lists ways
you can ease the load on the sewer.
State of the Beaches 2003–2004
Table 1: Ways to Improve Stormwater Quality
Actions to do more often
Actions to avoid
• Pick up litter in the park or on the street.
• Washing the car in the street.
• Sweep the gutters and driveways regularly and place
the sweepings on the garden, in the compost or in
the bin.
• Hosing dirt off hardstand surfaces (roads, paths,
driveways) into gutters.
• Do not allow soil or mulch to be washed or blown off
the garden.
• Clean up pet droppings and dispose of them in the
garden, rubbish bin or toilet.
• Rake up leaves or lawn clippings and use them as
mulch on the garden or place them in the compost.
• Grass or replant areas of disturbed soil.
• Consider natural alternatives to pest-control
chemicals.
• Maintain the car, making sure there are no leaks and
that the fuel is burnt ‘cleanly’ by keeping the vehicle
tuned.
• Use the minimum amount of detergent for cleaning
outside.
• Wash brushes and rollers over a sand filter on the
lawn.
• Wash cars on the lawn or gravel and use minimal
detergent. Empty the soapy water down the sink or
toilet. Alternatively, take the car to a car wash where
the water gets treated and recycled.
• Dropping packaging or cigarette butts on the ground.
• Leaving rubbish where bins are already full.
• Hosing leaves and grass clippings into gutters.
• Piling sand and soil on areas where it can wash into
the stormwater system.
• Washing cement mixes into the gutter.
• Overuse of chemicals (pesticides and herbicides)
that could be washed into stormwater from the
garden or yard.
• Using too much fertiliser (follow the instructions).
• Using pesticides, herbicides and fertiliser when rain
is forecast the same day.
• Disposing of oil or chemicals into gutters.
• Maintaining cars, including oil changes, where oil and
grease may wash into gutters.
• Pouring paint, solvent or cleaners in the gutter or
where they may enter drains.
• Covering large areas with impervious surfaces, e.g.
concrete, bitumen.
• Drive less – use public transport, walk, or ride a bike.
• Make sure sewerage pipes are not connected
illegally to stormwater.
• Install a rainwater tank.
• Direct roof runoff from downpipes to the garden (with
council approval).
• Replace impermeable surfaces (e.g. concrete) with
permeable surfaces such as timber decks and pavers
(with gaps between pavers).
• Get involved with Bushcare or Landcare projects that
restore or protect local waterways.
Table 2: Ways to Ease the Load on the Sewer
Actions to do more often
Actions to avoid
• Install dual flushing in the toilet.
• Putting oil down the sink.
• Get sewer pipes smoke tested for false stormwater
connections.
• Tree root damage to sewer pipes.
• Use a sink strainer.
• Use the dishwasher and washing machine only when
there is a full load. This not only reduces the amount
of detergents entering the sewer system, but also
saves water and energy.
• Stormwater entering outdoor sewer pits.
• Putting vegetable scraps, tea leaves, coffee grounds
or eggshells down the sink. These can be
composted.
• Using the toilet as a garbage bin by flushing
tampons, sanitary napkins, condoms, cotton buds
and cigarette butts down the toilet. Place them in a
bin instead.
• Washing hair down drains. This can be composted.
Preventing Beach Pollution
15