Torbay Inlet is an

estuarine An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environment ...

inlet An inlet is a (usually long and narrow) indentation of a shoreline, such as a small arm, bay, sound, fjord, lagoon or marsh, that leads to an enclosed larger body of water such as a lake, estuary, gulf or marginal sea. Overview In marine geogra ...

in the Great Southern region of

Western Australia Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to th ...

situated approximately east of the town of

Denmark, Western Australia Denmark is a coastal town located on Wilson Inlet in the Great Southern region of Western Australia, south-south-east of the state capital of Perth. At the 2016 census, Denmark had a population of 2,558; however, the population can be ...

. Torbay Inlet is a wave-dominated estuary that functions primarily as a result of

wave energy Wave power is the capture of energy of wind waves to do useful work – for example, electricity generation, water desalination, or pumping water. A machine that exploits wave power is a wave energy converter (WEC). Waves are generated by wind p ...

. The estuary has been severely modified as most of the natural

catchment A drainage basin is an area of land where all flowing surface water converges to a single point, such as a river mouth, or flows into another body of water, such as a lake or ocean. A basin is separated from adjacent basins by a perimeter, the ...

cover has been cleared. Covering a total surface area of , of this is the central basin with the remainder being composed of saltmarsh and tidal delta. The lagoon is quite shallow and fringed with

sedges The Cyperaceae are a family of graminoid (grass-like), monocotyledonous flowering plants known as sedges. The family is large, with some 5,500 known species described in about 90 genera, the largest being the "true sedges" genus ''Carex'' wit ...

and

paperbark ''Melaleuca'' () is a genus of nearly 300 species of plants in the myrtle family, Myrtaceae, commonly known as paperbarks, honey-myrtles or tea-trees (although the last name is also applied to species of ''Leptospermum''). They range in size f ...

s. The inlet outflows into the

Southern Ocean The Southern Ocean, also known as the Antarctic Ocean, comprises the southernmost waters of the World Ocean, generally taken to be south of 60° S latitude and encircling Antarctica. With a size of , it is regarded as the second-small ...

and is part of the Torbay Inlet and Lake Powell Catchment Area. Much of the land surrounding the inlet has an elevation of less than so that under certain tidal and wind conditions the land is inundated with sea water that floods back up the estuary. As a result, in 1912, a barrage with floodgates was constructed to prevent this, but this proved to be unsuccessful. A

sandbar In oceanography, geomorphology, and Earth science, geoscience, a shoal is a natural submerged ridge, bank (geography), bank, or bar that consists of, or is covered by, sand or other unconsolidated material and rises from the bed of a body o ...

exists across the mouth of the estuary for most of the year, but it is often breached following significant rain events. Trekkers on the

Bibbulmun Track The Bibbulmun Track is a long-distance walk trail in Western Australia. It runs from Kalamunda in the east of Perth to Albany, and is long. It is managed by government agencies, and has a foundation. It traverses the Darling Range and has i ...

use the either the sandbar to cross the inlet or an alternative route using the Lower Denmark Road to go around the inlet.

Catchment

The catchment area is one of the most altered on the South Coast. The inlet drains a large swampland area that includes Lake Powell, Lake Manarup, Five Mile Swamp, Seven Mile Swamp and Marbelup Brook along with a number of man-made agricultural drains. The area of the catchment is of which 55% has been cleared and contains of water ways. Some swampland in the lower catchment was drained to open land for

agriculture Agriculture or farming is the practice of cultivating plants and livestock. Agriculture was the key development in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that enabled people to ...

. Unfortunately this exposed

pyrite The mineral pyrite (), or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Iron, FeSulfur, S2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral. Pyrite's metallic Luster (mineralogy), lust ...

in the soil that oxidised in the open air rendering the soil

acid In computer science, ACID ( atomicity, consistency, isolation, durability) is a set of properties of database transactions intended to guarantee data validity despite errors, power failures, and other mishaps. In the context of databases, a sequ ...

and infertile.

Watershed Torbay

Watershed Torbay was a four-year project which planned and implemented a

restoration Restoration is the act of restoring something to its original state and may refer to: * Conservation and restoration of cultural heritage ** Audio restoration ** Film restoration ** Image restoration ** Textile restoration * Restoration ecology ...

plan for the Torbay Catchment. The Torbay catchment Group is the

community group Community organizing is a process where people who live in proximity to each other or share some common problem come together into an organization that acts in their shared self-interest. Unlike those who promote more-consensual community bui ...

that formed in 1999 to implement the restoration plan. The activities of the group include establishing and repairing fencing around the waterway, Watsonia control and Wetland construction for

nutrient A nutrient is a substance used by an organism to survive, grow, and reproduce. The requirement for dietary nutrient intake applies to animals, plants, fungi, and protists. Nutrients can be incorporated into cells for metabolic purposes or excret ...

stripping.

References

Estuaries of Western Australia Great Southern (Western Australia) South coast of Western Australia {{WesternAustralia-geo-stub