{{Short description|Lake in Tasmania, Australia}} {{Use dmy dates|date=June 2020}} {{Use Australian English|date=August 2019}} {{Infobox body of water | name = Lake Fidler | native_name = | native_name_lang = | other_name = | image = | alt = | caption = | image_bathymetry = | alt_bathymetry = | caption_bathymetry = | location = South West Tasmania | group = | coordinates = {{coord|42|30|31|S|145|40|37|E|type:waterbody_region:AU-TAS|display=inline,title}}<!-- {{coord|DD|MM|SS|N|DD|MM|SS|W|region:ZZ_type:waterbody|display =inline,title}} --> | type = Meromictic | etymology = | part_of = | inflow = | rivers = | outflow = | oceans = | catchment = | basin_countries = Australia | agency = | designation = Tasmanian Wilderness World Heritage Site area | date-built = <!-- {{Start date|YYYY|MM|DD}} For man-made and other recent bodies of water --> | engineer = | date-flooded = <!-- {{Start date|YYYY|MM|DD}} For man-made and other recent bodies of water --> | length = | width = | area = | depth = | max-depth = | volume = | residence_time = | salinity = | shore = | elevation = | temperature_high = | temperature_low = | frozen = | islands = | islands_category = | sections = | trenches = | benches = | cities = | pushpin_map = Australia Tasmania<!-- the name of a location map as per Template:Location map. Requires coordinates= parameter to display map. --> | pushpin_label_position = <!-- left, right, top or bottom --> | pushpin_map_alt = | pushpin_map_caption = Location in Tasmania | website = | reference = }} '''Lake Fidler''' is a meromictic lake beside the Gordon River in the Tasmanian Wilderness World Heritage Site area of the west coast of Tasmania, Australia. The lake has a layer of fresh water overlying an anoxic salt water layer. The meromictic lakes and ponds of the Gordon River were discovered by D. A. Hodgson and Professor Peter Tyler.<ref>{{cite journal|author1=Hodgson, D.|author2=Tyler, P. A.|author3=Vyverman, W.|year=1996|title=The paleolimnology of Lake Fidler, a meromictic lake in south-west Tasmania and the significance of recent human impact|journal=Journal of Paleolimnology|volume=18|issue=4|pages=313–333|doi=10.1023/A:1007995614287}}</ref>
==Description== It became evident that, following the establishment of a hydro-electric power industry on the Gordon River, the flows of fresh water into the lake were disturbed and the anoxic salt layer was declining in depth. Previously, low river flows at certain times of the year allowed salt water to migrate upriver and occasionally spill into Lake Fidler through a narrow channel joining it to the river, thus recharging the salt water layer.
In 2004, Hydro Tasmania gained state and federal approval to recharge the lake with seawater drawn from the sea outside Macquarie Harbour at the mouth of the Gordon River. This involved having a sea-going tug draw up approximately {{convert|1.4|e6l|e3impgal e3USgal|lk=on}} of salt water in lots of approximately {{convert|100000|L|impgal USgal}}, and discharge the water through a diffuser that allowed the seawater to settle into the lower salt layer. (See diagrams at Hydro Tasmania press release, 18 June 2004) This was completed and the results confirmed in April 2005. However, it was noted that, if no natural recharging occurs, the process of recharging may need to be repeated in about 10–15 years.
==See also== {{stack|{{Portal|Australia|Water}}}} *{{section link|List of reservoirs and dams in Australia|Tasmania}} *{{section link|List of lakes of Australia|Tasmania}}
==References== {{reflist}}
==Further reading== * {{cite journal|author1=Hodgson, D. A.|author2=Tyler, P. A.|year=1996|title=The impact of a hydro-electric dam on the stability of meromictic lakes in south west Tasmania, Australia|journal=Archiv für Hydrobiologie|volume=137|number=3|pages=301–323}} * {{cite journal|author1=Hodgson, D.|author2=Wright, S.|author3=Tyler, P.|author4=Davies, N.|year=1998|title=Analysis of fossil pigments from algae and bacteria in meromictic Lake Fidler, Tasmania, and its applications to lake management|journal=Journal of Paleolimnology|volume=19|issue=1|pages=1–22|doi=10.1023/A:1007909018527|bibcode=1998JPall..19....1H}} * {{cite journal|author1=Hodgson, D.|year=1999|title=The formation of flocculated clay laminae in the sediments of a meromictic lake|journal=Journal of Paleolimnology|volume=21|issue=3|pages=263–269|doi=10.1023/A:1008064029510|bibcode=1999JPall..21..263H}}
==External links== *[https://web.archive.org/web/20050511145736/http://www.hydro.com.au/home/Corporate/Media+Releases/Media+Releases+2004/Major+project+to+revive+meromictic+lake.htm Hydro Tasmania press release, 18 June 2004] *[http://www.deh.gov.au/cgi-bin/epbc/epbc_ap.pl?name=show_document&document_id=12588&proposal_id=1334 Hydro Tasmania proposal to Australian Department of Environment and Heritage] under Environment Protection and Biodiversity Conservation Act 1999; DOC file, with maps
{{Lakes of Tasmania|state=autocollapse}}
{{DEFAULTSORT:Fidler}} Category:Lakes of Tasmania Category:Meromictic lakes Category:Tasmanian Wilderness World Heritage Area