General
Environmental flows are commonly releases of water from dams and
impoundments which are intended to meet a balance of social, economic
and environmental needs. They generally seek to mimic as far as
is practicable pre-development conditions.
The timing, volume and quality of environmental flows are all critical
aspects and, just as with the natural flow of rivers, different
combinations will provide a different range of benefits for each
ecosystem.
Environmental flows seek to ensure that the key chemical, geomorphological,
and ecological processes necessary for healthy river ecosystems
improve in their function.
Environmental Benefits of Environmental Flows
- improvements in the nature and frequency to more closely reflect
natural variability in the different levels of flows (high, medium
or low), within river channels and billabongs and across floodplains;
- moves carbon (the product of decomposition of material buried
or lying on the floodplain) between the river floodplain and wetlands,
which science indicates is a key factor in maintaining healthy
rivers;
- improves river bank vegetation health, which stabilises banks
and slows erosion;
- stimulates native fish such as cod, yellowbelly and catfish
to move onto the floodplain to feed and breed;
- provides freshwater and food for estuarine and marine fish
and shellfish, at the lower end of the catchment;
- provides flows of sufficient depths and duration for waterbirds,
such as ibis, cormorants and night herons, to build nests, breed
and raise chicks to fledging age;
- provides soil moisture for plant growth and development;
- replenishes aquifers and dilutes salty water left in wetlands
and billabongs following evaporation;
- stimulates invertebrate eggs to hatch and plant seeds to germinate;
- provides floodplain vegetation as food for native and domestic
animals; and
replenishes the floodplains by depositing soil and nutrients on
the floodplain.
Nature Conservation Council of NSW
http://www.nccnsw.org.au/water/context/flows_fs.html
World Conservation Union
http://www.waterandnature.org/flowlaunch.html
Protocol
Various methods for assessing/setting environmental flows
http://www.lk.iwmi.org/ehdb/EFM/visitors/ViewAllMethodology.asp
Environmental Flow methods applied to Tasmanian Rivers
http://www.dpiwe.tas.gov.au/inter.nsf/WebPages/JMUY-5F93LC?open
Case Study
Tumut Shire Council
http://www.tumut.nsw.gov.au/soe/SoE/IndicatorResults/EnvironmentalFlows.htm
Integrated Monitoring of Environmental Flows
DLWC
http://www.dlwc.nsw.gov.au/care/water/imef/new_design_report.pdf
Snowy River
http://www.thelivingmurray.mdbc.gov.au/content/index.phtml/itemId/15583/fromItemId/2747
Sydney Catchment Authority
Environmental Flows from dams
http://www.sca.nsw.gov.au/dams/flows.html
Murrumbidgee River environmental flows
http://www.envcomm.act.gov.au/Soe2000/ACT/IndicatorResults/Environmentalflows.htm
Person contact
Rebecca Pinto
Tasmanian Department of Primary Industries
Senior Aquatic Ecologist (Environment)
13 St Johns Avenue NEW TOWN TAS 7008
New Town TAS 7008
Phone: 03 6233 3128
Fax: 03 6233 6881
Email: Rebecca.Pinto@dpiwe.tas.gov.au
Organisation Contact
Department of Environment and Heritage
Director
Inland Waters Section
(02) 6274 1955
www.deh.gov.au/water
www.deh.gov.au/water/wetlands
Advanced reference
National River Health Program
Current research
http://www.deh.gov.au/water/rivers/nrhp/flows/projects.html#paroo
|
