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Bega Valley Shire Council operates four water supply systems
and six sewage treatment plants, these are located at:
Water supply system - Kiah-Tantawanglo
The Kiah-Tantawanglo system supplies Candelo, Eden,
Merimbula, Pambula, Pambula Beach, South Pambula, Tura Beach and Wolumla
and includes the following major assets:
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Four water sources/storages (Towamba River aquifer
at Kiah (5 shallow bores), Yellow Pinch Dam, Ben Boyd Dam and
Tantawanglo Weir)
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Two chlorination plants (Yellow Pinch Dam and
Boydtown Balance Tank),
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Two UV plants at Candelo and Wolumla
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26 reservoirs/storages
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10 pumping stations
This the largest system in the Shire with the highest
population growth rate but the least secure supply. It is affected by
drought and the maximum system yield of 2,900 ML/a is rarely achievable
due to low stream flows and environmental flow restrictions. Future
water sharing plans and environmental flow restrictions are likely to
reduce yields further. Current demand is close to system capacity and
system augmentation is required to improve supply security.
Water quality from Towamba River is generally good but
water from Tantawanglo Creek can be high in colour, suspended solids and
bacteria following rain. The villages of Candelo and Wolumla receive
water disinfected with UV light and some customers upstream of Yellow
Pinch Dam receive raw water only. These customers receive relatively
poor water quality following rainfall. Blue green algae also occur in
Yellow Pinch Dam and Ben Boyd Dam each summer and autumn. Water from the
dams is disinfected with chlorine only. Additional treatment is proposed
to improve disinfection and remove algae.
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Water supply system - Bega - Tathra
The Bega-Tathra system supplies Bega, Kalaru,
Mogareeka, Tathra, Tarraganda and Tathra River Estate and includes the
following major assets:
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One water source (6 bores west of Bega on the Bega
River);
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One chlorination and fluoridation plant (High
Street Reservoir);
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13 reservoirs/storages (North Bega, High Street,
Tarraganda, Belmore Street, South Bega Reservoir, South Bega Balance
Tank, Kalaru, Tathra River Estate, Mogareeka, Tathra, Tathra Trig
reservoir, Aquamarine storage reservoir and service reservoirs); and
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Five pumping stations (High Street, South Bega,
Jellat, Aquamarine and one Standby at Kalaru).
The Bega-Tathra system has adequate capacity to serve
existing and future customers as the bores are located in a large
alluvial aquifer at the lower end of the largest catchment in the Shire.
Droughts and extraction by irrigators can cause some problems due to
localised drawdown around the borefield. There is a large volume of
water in aquifer storage so supply is adequate during low surface flows.
Water quality is generally good although high iron
levels occur. Water is chlorinated and fluoridated only.
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Water supply system
- Brogo - Bermagui
The Brogo-Bermagui system supplies Akolele, Bermagui,
Cobargo, Quaama, Bermagui and Wallaga Lake and includes the following
major assets:
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Four water sources including Illawambra Weir,
Tilba Dam (rarely used), Couria Creek Weir and Brogo Dam operated by
State Water);
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Three chlorination plants located at Brogo Dam,
Cobargo Reservoir and Tilba Dam;
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10 reservoirs/storages (No 1 Balance Tank, Quaama,
Cobargo, Wallaga Lake (private), Akolele, Beauty Point, No 2 Balance
Tank, Barragoot Street, Bermagui West and Bermagui South); and
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Three pumping stations (Brogo Dam, Tilba, Wallaga
Heights Booster).
This system relies on releases from Brogo Dam, which
is operated by State Water. The dam has adequate storage to meet current
and future demands. Most of the water released from Brogo Dam is for
dairy pasture irrigation with other uses being environmental flows,
stock and domestic uses, riparian uses and dairy washdown.
Poor water quality can occur when the dam level is
low. Water quality is generally fair to good, although the water is soft
and occasionally high in colour, iron and suspended solids. Some water
quality complaints occur and disinfection is compromised during dam
turnover. Soft water and the high levels of chlorination can cause
copper corrosion in the system. A secondary chlorination plant located
near Bermagui and a water treatment plant at Brogo are planned.
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Water supply
system - Bemboka
The Bemboka system supplies Bemboka only. Water is
sourced from the Bemboka River and Cochrane Dam (operated by Eraring
Energy). The system includes one reservoir.
This system is very small with low demand. Water
sharing and dam release arrangements are serving Bemboka well.
Suspended solids, colour and iron can cause water
quality issues, especially following rain. A Spin-Klin disc filtration
system is used and water is disinfected with chlorine. A water treatment
plant is planned for Bemboka.
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Sewage treatment
plant - Bega
The Bega STP was initially constructed in 1935 and has
been upgraded several times to accommodate increasing loads and effluent
quality requirements. The current plant is based on a conventional rock
media trickling filter and incorporates primary clarification and
anaerobic digestion of primary and humus sludge.
The wastewater is predominantly residential.
The treated effluent is directed to a series of
lagoons, where further natural treatment and disinfection takes place. A
portion of the lagoon water is directed to a private farm dam, from
where it is beneficially reused for irrigation of pasture. Excess water
overflows from the lagoon to the Bega River. Sludge stabilisation and
dewatering are by sludge lagoon and sludge drying bed. Sludge disposal
is to landfill after stockpiling on site.
The Bega STP is being upgraded as part of the BVSP
(capacity 8,000 EP).
In 2003/2004 effluent disposal was 60% to dairy
irrigation and 40% to the Bega River.
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Sewage
treatment plant - Bermagui
The Bermagui STP is a ‘Pasveer channel’ style
activated sludge plant. The effluent is disposed to an ocean outfall
with some reuse as irrigation water on the adjacent golf course. Sludge
stabilisation and dewatering are by sludge lagoon and sludge drying bed.
Sludge disposal is to landfill after stockpiling on site.
The wastewater is predominantly domestic. The plant
treats flow only from the Bermagui catchment. There is no screenings or
grit removal.
The Bermagui STP is being upgraded as part of the BVSP
to include clarification and disinfection with a capacity of 6,000 EP.
In 2003/2004 effluent disposal was 69% to the ocean
and 31% to the golf course.
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Sewage treatment
plant - Eden
The Eden sewerage system consists of approximately
40km of gravity sewer pipes, six pumping stations and a treatment plant.
The Eden STP is an intermittent style activated sludge
plant (‘Bathurst Box’) with tertiary lagoons. The effluent is disposed
of to ocean with some reuse as irrigation water on the adjacent golf
course. Sludge disposal is to landfill after stockpiling on site.
The connected population is predominantly residential
with a small amount of light industry. The plant treats flow only from
the Eden catchment. There is no grit or screenings removal.
Disinfection will be provided at the Eden STP as part
of the BVSP.
In 2003/2004 effluent disposal was 72% to the ocean
and 28% to the golf course.
Eden sewerage system is known to be vulnerable in wet
weather and has a history of inflow/infiltration problems. Following an
extensive CCTV inspection, some mains have been identified as high risk
and in need of rehabilitation.
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Sewage
treatment plant - Merimbula/Pambula
The Merimbula STP is an intermittent style activated
sludge plant (‘Bathurst Box’) with a tertiary lagoon. The effluent is
currently disposed of to ocean with some reuse as irrigation water on
the adjacent golf course. Sludge stabilisation and dewatering are by
sludge lagoon and sludge drying bed. Sludge disposal is to landfill
after stockpiling on site.
The population is predominantly residential with some
light industry. The plant treats flow from the Merimbula and Pambula
catchments (including Pambula South and Pambula Beach). There is no grit
removal.
BVSC aims to reduce effluent discharges to ocean and
prefers reuse applications. The BVSP includes upgrading the Merimbula
STP to enhance effluent quality with reuse to the golf course and nearby
farming ventures (Pambula Flats).
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Sewage treatment
plant - Tathra
The Tathra STP is a ‘Pasveer channel’ style activated
sludge plant incorporating a clarifier and disinfection. The Tathra STP
was upgraded as part of the BVSP to include clarification and
disinfection with transfer of all treated effluent to the golf club.
The effluent is beneficially reused on the adjacent
golf course and playing field. Sludge stabilisation and dewatering are
by sludge lagoons and sludge drying beds. Sludge disposal is to landfill
after stockpiling on site.
The connected population is predominantly residential,
with only very light industry in the area. The plant treats flow only
from the Tathra catchment.
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Sewage treatment
plant - Tura Beach
The Tura Beach STP is a continuous style activated
sludge plant (‘Bathurst Box’) incorporating a clarifier. The plant also
includes a Pasveer channel which was the original plant and is now used
rarely. Sludge stabilisation and dewatering are by sludge lagoon and
sludge drying bed. Sludge disposal is to landfill after stockpiling on
site.
The effluent is disposed of via an ex-filtration
system with some reuse as irrigation water on the adjacent golf course.
The connected population is almost all residential in
nature. The plant treats flow only from the Tura Beach catchment. There
is currently no grit removal and alum is dosed to assist settling.
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