Aqueduct - A transport channel for water

Aquifer - A permeable geological formation that allows groundwater movement through it

Aquitard - A geological formation that restricts groundwater movement

Baseflow - Normal flow conditions in a stream or river

Catchment - An area where water is collected by the natural landscape in a catchment, all rain and run-off water eventually flows into a creek, river, lake or ocean or into the groundwater system

Deep storage - Water that lies at the bottom of some dams and reservoirs. It is usually below the lowest outlet point in a dam that water can be extracted from, or below the level where gravity can draw water out of the dam

Environmental flows - Flows of water released from dams into a river, stream or other natural waterway to protect and improve river health

Exfiltration - Seepage

Groundwater - All water found below ground level in saturate soil or rocks

Hydroclimatic - Influence of long-term climate on water bodies

Hydrogeology - The study of distribution and movement of groundwater

Hydrology - The study of water movement

Joule - The work done to produce the power of one Watt continuously for one second

Land - Includes rivers, streams and other watercourses

Macroinvertebrate - Aquatic invertebrates including insects, molluscs, crustaceans and worms that can be indicators of aquatic health

Megalitre - A volume equal to one million litres

Operating storage - The amount of water available for water supply in a lake or reservoir

Pathogen - Micro-organisms that can be found in water and which can sometimes cause illness in humans

Petajoule - One million billion joules

Rain event - Rainfall exceeding a threshold value set according to catchment size

Raw water - Water that has not been treated

Regional plan - The regional plan for Sydneys drinking water catchments and adjacent regional centres

Riparian - Refers to land adjacent to a water course such as a riverbank

Sewage - Wastewater from domestic sources

Sewerage - Pipe network that transports wastewater from domestic sources to sewage treatment plants

Special Areas - Land set aside to protect drinking water quality, usually located close to the water supply

Subsidence - Downward movement of the Earths surface

Terajoule - One million, million joules

Upper Canal - The 65 kilometre channel that transports water from Metropolitan water storages to Prospect Water Treatment Plant

Upsidence - Upward movement of the Earths surface

Water storages - The SCAs dam walls, pumps and other works used for extracting and storing water in rivers and lakes, water occurring naturally on the surface of the ground and sub-surface waters

Water supply - The SCAs dams, pipelines of associated works, and infrastructure monitoring devices

Yield - The amount of water that can be continually withdrawn from a reservoir on an ongoing basis with an acceptably small risk of reducing the storage to zero