Logging industry propaganda
Logging has no impact/ negligible impact on water supply. Link
Water restrictions are/where caused by drought not logging. Link
Research by Sinclair Knight Merz(SMZ) shows logging has no impact
on current water yield from forest. In fact it may still rise slowly.
SKM Research shows logging in water catchments involves Best Management
Practices (BMP). Link
The biggest impacts on water catchments are agriculture and urbanisation.
Half the Gellibrand catchment is private land for which agriculture
and urbanisation are the biggest threats to water not logging. Link
Measures are in place to prevent landslides in the Otways.
Wild fire is the greatest risk to catchments not logging. Catchment
areas burn so regularly that it is unlikely they will ever reach a
state of old forest and high water yield. Link
There is a 200 meter buffer applied around water storage's to protect
Water yield will increase by an average of 6% per annum not 10%.
- It has been scientifically proved that the age
of a forest impacts on the amount of water run off. Young vigorously
growing trees that grow after clearfell logging in wet forests can reduce
the quantity of water run-off into catchments. See Kuczera
- Independent research released by Sinclair Knight Merz Research in
2001 shows that if clearfell logging in the Otways ended in the West
Barwon Catchment or Arkins
Creek catchment, water run off would increase by 10% and 28% respectively.
- A 10% increase in water runoff from the West Barwon dam is equivalent
to the water consumption of city of 10,000 people. See link.
- The comment "water restrictions are caused by drought" is
irrelevant to the debate about the impact of clearfell logging on water
yield. The fact that there where four years of water restrictions in
the Geelong region (1997-2001) simply helped focus the community on
the issues surrounding water availability for domestic use and the impact
logging has on water supply.
Three scenarios were investigated by SKM into the impacts of logging
on water runoff in the Otways. These were:
2. currently levels of logging proposed under the RFA.
3. 50% of the catchment burnt by a bushfire.
These three scenarios were applied to West
Barwon catchment and Arkins
The statement only refers to scenario No.2 and
ignores other possible futures offered by scenario No.1 and No.3.
BMPs are practices designed to protect or minimise the impact of logging
practices on soil and water values. Such practices outlined in the Code
of Forest Practices and Otway
Forest Management Plan include retaining forested buffer strips along
streams, no logging over 30 degrees, location and rehabilitation of log
landings sites and the design and location of logging roads.
The SKM research acknowledged that measures outlined in the Code of Forest
Practices are generally implemented in the Otways , however:
1. it is not known how effective these measures actually are to protect
of soil and water values. SKM referred to the lack of research into the
effectiveness of BMPs across Victoria. See SKM
2. SKM highlighted a lack of
prescriptions required to identify or response to landslides risks
caused primarily by logging roads in the Otways.
Note: landslides were called "mass movement hazard" by SKM.
- The catchments for Geelong, Apollo Bay and Lorne do not have any agriculture
or urbanisation in their headwaters. The headwaters are predominantly
native forest. Hence for these catchments, the issue of agriculture
and urbanisation is irrelevant.
- The issues regarding agriculture and urbanisation are only partly
relevant to the Gellibrand catchment. About 56% of the Gellibrand is
public land with native vegetation. Overall, 70% of the Gellibrand catchment
is still forested. See Gellibrand
- The Gellibrand proclaimed catchment area(66,570 ha) is mostly a forested
catchment with 70% native forest. About 17% is cleared agricultural
land and 13% is plantations (mostly radiata pine). The majority of the
high rainfall/recharge areas still have native forest with about 80%
of the cleared agricultural land located in the valley of the Gellibrand
river which has a lower rainfall. See Gellibrand
- Urban impacts within the Gellibrand catchment are small and classed
as light urban. There are only small towns within the catchment that
include Carlisle, Gellibrand, and parts of Lavers Hill and Beach Forrest.
- Clearfell logging practices add another level of disturbance and risk
to water values already under stress from private land users.
- Stopping logging on the significant public land component of the Gellibrand
catchment will improve summer flow reliability when domestic consumption
from Warrnambool and the Dairy Industry is at its highest. See Gellibrand
river summer flow vulnerability.
- There are no prescriptions to prevent logging induced landslides in
the Otways. This includes nothing in the Code of Forest Practices for
Timber Production or the Otway Forest Management Plan.
Note: landslides were called "mass movement hazard" by SKM.
See lack of landslide prescriptions.
- High rainfall events are a major cause of landslides and water degradation
associated with logging practices. An example of this occurred at HP
track in November 1995[water\22landslides.htm]. Despite this, there
is little research being conducted.[ water\25rainlandslide.htm]
- It is a myth that wet forests that have evolved in high rainfall areas
have high tendency to burn. Research highlightes the fact that wet Otway
forest are not a fire prone environment. In fact catchments that have
never been disturbed by logging such as Olangolah (Colac's water supply)
contain forest that is over 150 years old.
See Fire Occurrence in Otway
- Forestry Victoria have
hypocritically contradicted themselves regarding their claims on fire
frequency in propaganda documents released to the public. The contradiction
basically implies a wildfire can discriminate between forest available
for clearfell logging in catchment areas and forest protect in reserves..
- This Forestry Victoria fire contradiction adds weigh to the argument
that logging practices are making wet forest more fire prone in catchment
areas and hence increasing the risk of major reductions in water yields.
See Clearfell logging is
making the wet forests of the Otways drier and more fire prone
- Clearfell logging occurred within 200 metres of the West Barwon Dam
high water mark in 1997. This was a clear breach of the Otways Forest
Management Plan and has been acknowledged by Barwon Water.
See Logging within
200 metres of West Barwon.
- This use of averages to determine the increase in water yield if logging
was is stopped misrepresents the magnitude of water yield gains that
can be achieved. If logging was stopped in the West Barwon catchment,
it will take 60 years to achieve a 10% increase in water run off and
it will stay at approximately 10% more for decades or centuries after.
See Kuczera Curve
See West Barwon catchment