gdes matter; understanding the role that groundwater plays

GDEs Matter; Understanding the role that groundwater plays in urban ecosystems in the Melbourne region (abstract 123).

Enabling rapid GDE assessments and referral

Overview

• Muddy waters

• Who’s who in the zoo?

• How urban development has grown.

• Stirring the waters

• Overview of Melbourne Water Program.

• Clearing the waters

• Implementation and examples using Merri Creek

Muddy Waters

Australia, Victoria and Melbourne

STREAM REFUGES

SALINE WETLANDSFRESHWATER WETLANDS

RIPARIAN WOODLANDS

BILLABONGSMINERAL SPRINGS

Who’s who in the zoo

• Urban Growth Authority –urban growth planning.

• Friends of Merri Creek –community group.

• Southern Rural Water –resource manager

• Melbourne Water –caretaker of river health

Environment Resources

Development Planning

Community

Future growth for Melbourne

Stirring the waters

Bill Moulden (MW)

Time Line

Pre 2010

No maps of groundwater interaction with ecosystems

No structure to assess their water requirements

No structure / policy to integrate them into management

Post 2010

GDE Atlas

-National map of potential GDEs

GDE Tool Box

-Approached to assessing the water requirements of GDEs

Melbourne Water GDE Management Plan

-established the way forward – how to manage GDEs within a Urban environment

MW GDE Management Program – Overview

How do we deliver the program?

Understand

Build our understanding and knowledge of GDEs

and actions required to protect and enhance them.

1 Identify GDE

• Investigation

• Proactive - priority GDEs

• Reactive - various investigation

GDE workspace and catalogue

Prioritisation of GDEs

Plan

Prioritise and guide our efforts to manage

GDEs.

2. Assess GDE.

If Yes - continue to next step

If No - update GDE catalogue (ewaterteam audit)

Desk top assessment

Field assessment

GDE handbook

GDE catalogue

Engage

Exchange knowledge and build support for action to protect and

enhance GDEs

3. Conceptual understanding

Role GW plays

Data gaps

Condition assessment

Detailed assessment

Conceptual model approach

GDE condition assessment

GDE catalogue

Deliver

Undertake actions to protect and enhance

GDEs

4. Management Plan

Management objectives

Local, catchment and regional scale.

Management Plan template and methodology

GDE catalogue

Program area

Aim

Process

Documents

Clearing the waters

The scenario

A new urban development / expansion or associated infrastructure

1. Increase in surface flow events – ephemeral to permanent stream flow

2. Potential reduction in infiltration / recharge

Melbourne Water are obliged to assess risk to GDEs

1. Interrogated existing data base on GDEs

2. Complete a desk top and field (rapid) assessment

3. Make recommendation within a referral process

1. Identify GDE – e.g Merri Creek

GDE Data base (already existing)

• GDEs – wetlands and drought refuge reach

• GDE gw catchments – depth to gw, time of travel

• Stream interaction – gaining & losing streams

GDE catalogue (already existing)

• Attributes align to national atlas

• Updateable as sites investigated

Urban boundary encompasses the creeks GW catchment

2. Plan

Assessment overview - Undertaken by a non GDE expert

Prescriptive approach

Next steps

Not GDE - Update catalogueYes GDE - Complete stage 3 detailed

assessment

Field visit

Complete stage 2 field assessment with GDE handbook

Update catalogue with learnings

Desktop study

Complete stage 1 Assesment Update catalogue with learnings

GDE identified

MW GDE workspace Previous Fieldwork BOM Atlas

2. Plan

Desk top assessment

Location details

Aerial photos

Info from MW data abase (catalogue)

• Hydrogeology/ Geology

• Depth to water table

• Groundwater catchment info

2. Plan

Field assessment

• Overview

• Location details

• Sketch map

• Key features of landscape

Supported by a GDE Field Guide

2. Plan

Handbook

• Identifies types of GDEs and GDE knowledge sources

• Observation guide for identifying GDEs in the field

• Conceptual models illustrating hydrogeological settings of GDEs

3. Engage

Conceptual model approach

• Standardised template that links to the National Framework and to the GDE catalogue.

• Undertake literature review.

• Undertake site visit with local experts/interest.

• Developed a A3 size document – able to be read in 10 odd minutes.

• Understood by different stakeholders

3. Engage

Merri Creek

Naturally Ephemeral

Zone of discharge of slightly saline and warmer groundwater

Saline water prevents a fungus from infecting the frogs

The proposed urban development will alter the stream (fresher), reduce GW discharge

Exposing the Growling Grass Frog to the fungus

4. Deliver

GDE Management Plans - Sets out management objectives.

• Recommendations for the new urban development :-

• Site e.g fence out the creek

• Urban development needs to consider surface flow management• Reduce pavement flow, onsite storage - maintain ephemeral

nature of creek• Consider managing infiltration and recharge – maintain

groundwater levels

Outcome

• The GDE management plan enables a rapid referral process for GDEs – Melbourne Water often only have several weeks to respond

• Communication – enabled consideration of the ecological importance of groundwater to be integrated into current management regimes of new developments.

• Still more to do….But a long way further than 5 years ago

GASKILL, S Melbourne Water, PO Box 4342, Melbourne 3001. Australia [email protected], J CDM Smith, 393 OttreyScrub Road Walmer 3463. Australia HEARD, S Jacobs, PO BOX 260, Tatura 3616. Australia [email protected]

mailto:[email protected]


GASKILL, S Melbourne Water, PO Box 4342, Melbourne 3001. Australia [email protected], J CDM Smith, 393 OttreyScrub Road Walmer 3463. Australia HEARD, S Jacobs, PO BOX 260, Tatura 3616. Australia [email protected]

Any questions take it up with my daughter

