ACT Basin Priority Project
Improving long term water quality in the ACT and the
Murrumbidgee River System
Briefing to Woden Valley Community Council
4 March 2015
Project Background
• WMPA: Basin States to
undertake one or more
Priority Projects that will:
o Substantially contribute to
improved efficiency of
rural water use
o The sustainability of water
use
o Overall health of the Basin
ACT Basin Priority Project
• February 2014: the ACT Government signed a
funding agreement with the Commonwealth of
up to $85 million for the ACT Basin Priority
Project.
• The Project will Improve the Long Term Water
Quality in the ACT and the Murrumbidgee River
System
• The Project will be delivered in two phases with a
focus on six priority catchments
ACT Basin Priority Project
• Catchments selected to achieve representation of the broad
variety of catchment types and land development across the
Territory
o Yarralumla Creek –Mature catchment flowing into Molonglo River
o Lake Tuggeranong – Mature urbanised catchment flowing into Lake
Tuggeranong
o Upper Molonglo – Semi-rural catchment flowing into Lake Burley
Griffin
o Fyshwick – Industrial catchment flowing into Lake Burley Griffin and
Jerrabomberra Wetlands
o Lower Molonglo – Developing catchment flowing into Molonglo
o Riverview (West Belconnen) – Greenfield development flowing into
Murrumbidgee River
Governance Structure
Joint Commonwealth/ACT
Steering Committee
BPP Management Team
ACT and Region
Catchment
Management
Coordination
Group
Senior Executive
Water Group
(ACT Government)
Project Advisory
Group – Technical
Experts
Project Advisory
Group –
Community
Stakeholders
Future Delivery Team
Designers/Construction Contractors
Phase 2
Phase 1 – to Feb 2016
Pre-feasibility: Gathering data on existing
conditions & infrastructure
• Audit of WQ Data and establish data
management framework
• Water quality monitoring in 6 catchments.
• Pre-feasibility identification of options (GHD Synthesis
report)
• Audit of existing water quality infrastructure assets
Phase 1
Six catchments project – completed
March 2015
Objective:
• Water quality database
• Design and implement a water quality
monitoring framework for the six catchments
• Preliminary recommendations on
appropriate interventions (GHD Report on six
catchments)
Phase 1
ACT wide monitoring project – to June 2015
Framework for surface water and ground water based on water
quality objectives for the ACT.
Options include:
• Bathymetry
• Sediment sampling
• Micropollutants
Phase 1
Audit of Infrastructure project – to June 2015
Objectives:
• Audit a representative selection of existing stormwater assets;
• Advise on performance, efficiency and effectiveness,
maintenance and measures to improve performance;
• Options for the type and placement infrastructure assets
within the ACT.
• Looks at gross pollutant traps, rain gardens, swales, water
quality & settlement ponds and wetlands plus..
Phase 1 – To Feb 2016
Final Options Identification – April to September 2015
• Identification of treatment train options across 6 catchments
and in-lake
o Establish key environmental, social, economic criteria
o Develop investment framework and MCA tool
• Community engaged in option identification
Phase 1 – to Feb 2016
Business Case
• Ranked options to Cabinet – Sep 15
• Draft business case to Commonwealth – Dec 15
• Final business case to Commonwealth – Feb 16
Phase 2 -To be completed by March 2019.
• Will involve the construction or augmentation of water quality
infrastructure.
• Is subject to the Commonwealth Government’s final
assessment and agreement.
• A supplementary report to the initial business case utilising
information from Phase One will inform Phase Two.
Phase 2- Design and Construction
May 2016 to March 2019
• Design of approved treatment train infrastructure
• Development application approvals
• Construction
• Need to manage risk of short timeframe
The Yarralumla Creek system
• Yarralumla Creek the main drainage line
o Length 10 km
o Catchment 30 km2
• Drains from the south to the north, to
the lower Molonglo River
• Tributary Long Gully Creek drains the eastern part of the
catchment
The Yarralumla Creek system
• Established catchment
• Intensively urbanised
o 83% of catchment is utilised for
‘urban intensive uses’
• ‘Flashy’
o Increase of 0.9 of a meter within 5
mins at Curtin
The Problem – Yarralumla Creek
• High sediment and nutrient loads
entering the Molonglo
• Poor quality into Murrumbidgee River
• Steep, flashy system - erosion
• High flows and hydraulics limit
options available
• New development and shifts in
climate likely to place further
pressure on system
Flow Debris Up stream of Cotter Road
21 Feb – 3
monthly rainfall
event.
Water level and
flow response
significant
Organic load
BPP: Holistic Management
• Infrastructure proposals within catchment
• Management options in catchment (street sweeping)
• Practice change (leaves and clippings in open space)
and domestic)
Composting grass clippings,
garden waste and leaves helps
keep our waterways cleaner.
Catchment infrastructure options
1. Wetlands – low in the system on main drainage line
2. Naturalisation/riparian revegetation
3. Bio-retention (rain gardens) to remove
contaminants from stormwater runoff
4. GPTs – low in the system
Next Steps
Establish Multi-Criteria
Investment Framework
End Assignment
Catchment Options
Catchment
Options to
cabinet – End
September
Assess and Rank
Options across
Catchments
March April May June July August September
Catchment Options Analysis & Assessment
Start Assignment
Catchment Options
Community
expectation
research
Community
consultations on
infrastructure
options
Community Engagement
• Targeted engagement on:
– community expectations of water quality and waterways
– infrastructure options analysis
– design process
• Briefing to catchment and community groups
• Open house, factsheets and website
• Behaviour change campaign on catchment friendly behaviour
• Quarterly meetings of Project Advisory Groups – Community
Stakeholders
Community Engagement – Beyond 2015
• Consultation with community about successful infrastructure
proposals
• After construction, opportunity to become part of a
supported Parkcare Group assisting in caring for infrastructure
Proposed Infrastructure
and Management Options
• rea
• et / Management Option
Treatment / Management Options
Bio-retention system (aka bio-filtration system or raingarden)
Buffer Strips
Gross Pollutant Traps
Infiltration systems (also including porous pavements)
Media Filtration systems
Ponds
Rainwater tank
Sedimentation basins
Vegetated swales
Wetlands
Naturalisation of channel
Riparian revegetation
Floating wetlands
Evolution of water management
Waste-
water
Water
supply
Drainage
Water-
ways
Water
cycle
Water
sensitive
Drivers
Management responses
Population
growth
Public health Population
growth and
development
Social amenity;
environmental
health
“Limits to
growth”
Intergenerational
equity, resilience
to climate change
Supply
hydraulics
Separate
sewerage
schemes
Drainage/
flood
protection
Point source
and
stormwater
pollution
management
Diverse, fit-for-
purpose water
supplies linked
with waterway
protection
Adaptive and
multi-functional
infrastructure
and landscapes
Based on T. Wong and R. R. Brown 2009 The Water Sensitive City: Principles for Practice. Water Science and
Technology 60(3):673-682
Liveable
Quality of
urban
environment
Integrated
solutions, built
in to urban
form
Editor's Notes
Water quality improvements – a reduction in TSS, TP, TN, TC in catchments