September 29, 2000
Our Ref: 61/0900069
Direct line: 9429 6554
State Salinity Council
Level 15 International House, 26 St Georges Terrace
Perth WA 6000
Attention: Mr D Crawford
STATE SALINITY COUNCIL COMMUNITY SUPPORT SCHEME 2000 - PROJECT
Beacon River Catchment Salinity Management Project
We herewith submit further information on the above project as requested
in your letter to John Dunne dated 12 September 2000. This information
is submitted on behalf of the Mount Marshall LCDC to supplement the
Preliminary Project Proposal lodged with the Avon Working Group last
month. A copy of the original proposal is attached together with a revised
budget schedule reflecting a feasibility study phase to prove the methodology,
economics and sustainability of the proposed project.
Marshall Land Conservation District Committee
John Dunne, PO Box 45, BEACON, WA 6472.
PO Box 45, BEACON, WA 6472
Phone 9686 1045, Fax. 9686 1005,
The area to be considered within the study shall begin at the headwaters
of the Beacon River and extend to the southern boundary of the Mount
Marshall Shire (and beyond, should a hydrological analysis determine
that the effects of the proposed works are likely to be felt further
downstream). [Limited funds precluded downstream investigations]
the study shall investigate any means whereby floodwaters which accumulate
in Job's Lake may be safely discharged in order that the rising groundwater
problem affecting the catchment above Job's Lake may be addressed, ensuring
that whichever means adopted, shall not adversely impact upon any downstream
landform or waterway in the long term.
the safe discharge of the accumulated floodwaters in Job's Lake proves
feasible, the study shall endeavour to determine the best methodology
for the development of the Beacon River catchment salinity management
project as described in the Preliminary Project Proposal attached.
The feasibility study will have regard for social, environmental and
economic issues both on and off site, including assessment of the “do
nothing” option and its likely impact.
A budget and implementation plan for development of the project will
form part of the feasibility study should the project outcomes be deemed
attainable. It is expected that the completion date for the feasibility
study will be mid-2001.
The Preliminary Project Proposal (00S015) outlined a number of activities
that would be undertaken in the early stages of the project. These would
logically form part of a feasibility study for the project as further
described herein. It is intended that all participants already invited
shall become actively involved in the feasibility study. Other stakeholders
who have not yet been approached will be invited to participate in the
early stages of the study.
The feasibility study would review current knowledge about the catchment
and through liaison with the key agencies and stakeholders identify
and document the opportunities and constraints for implementation of
Recent consultation with hydrologists from Agriculture WA, CSIRO and
the Water & Rivers Commission concluded that gaining additional
data on the shallow groundwater level and quality was essential for
a proper understanding of the groundwater systems and for appropriate
planning and assessment of the scheme. A comprehensive aerial survey
using remote sensing techniques will be undertaken with ground proving
of selected sites to determine depths to the saline interface and to
map levels of salinity hazard in the catchment.
It is proposed that a number of shallow test pits will be excavated
and logged throughout the Beacon River catchment to identify current
groundwater levels and quality and to provide an indication of soil
types and variability. The test pits will be supplemented with a network
of shallow monitoring bores from which periodic (monthly) water level
readings would be obtained. A smaller number of deeper monitoring bores
(to bedrock, typically 20m deep) would also be established to provide
some guidance on the connectivity between the deeper and shallower groundwater
aquifers and to identify the hydraulic characteristics of the aquifers.
Samples of each dominant soil type would be obtained from the test pits
and bores and sent for analysis. Initial estimates of hydraulic properties
based on particle size analysis would be confirmed in the field through
permeameter testing during the drilling program.
Following completion of the hydrogeological field tests and drilling
program a report will be prepared presenting the results of the investigations
and recommending the parameters to be used for further planning and
design of the project. Ongoing monitoring of the established bores will
provide valuable data to determine water balances, groundwater responses
to rainfall events and to management practices implemented within the
catchment. The bores will also provide one means of measuring the effectiveness
of management practices implemented by this project, should it proceed
The surface water hydrology of the catchment will also be assessed.
The effects of flooding from periodic design events and from the rarer
flood events will be evaluated to establish planning constraints for
the proposed management options. Appropriate management of stormwater
runoff and flood flows will be necessary to ensure the integrity of
any constructed works. The impacts of flood events on the major lakes
of the catchment will be addressed. The hydrologic study will also consider
the water and salt balances of the lakes and the effects of discharges
to the downstream water bodies.
An initial environmental survey of the main lakes will be carried out
to assess the remnant natural vegetation and fauna dependent on the
lakes. The environmental assessment will attempt to identify the risks
to preservation of remnant communities and any constraints on the management
techniques to be proposed under this project.
Further development of the community consultation program will be carried
out under this feasibility study. Communication with and participation
of the community is of paramount importance in determining the success
of the project. Periodic reports in the local newspapers will keep the
community informed and invite active involvement and participation in
the planning of the proposed scheme. A concept design for proposed works
and potential alternatives will be prepared for comment.
A risk management workshop is proposed to be held locally involving
representatives of the community and key stakeholders as well as the
government and research agencies that will assist in the guidance and
development of the project. The purpose of the workshop will be to identify
the risks affecting the outcomes of the project, to assess the impacts
of those risks and to develop a prioritized strategy for managing risk
for the community’s benefit. A report will be prepared summarising
the outcomes of the risk management workshop and defining the actions
to be taken to monitor for and to deal with any adverse events that
Based on the outcomes of the technical, environmental, social and risk
studies, the concept design for proposed works will be finalised and
estimates of cost and likely benefits will be determined. A feasibility
report will be prepared summarising the findings of the earlier reports
and presenting the outcomes of the cost and benefits assessment.
I J WEAVER
and Rivers Commission
Land & Water, Shenton Park.
Manager, Catchment Management,
Environmental Systems Division,
Dept. of Environmental Protection
Shire of Mount Marshall
Secretary, Mount Marshall LCDC
Avon Working Group