STORMWATER GLOSSARY

A rainwater tank that is not in any way set into the ground.

An organisation accredited by NATA, or an equivalent international authority, to undertake specific tests required for evidence of suitability under the NCC. 

The body responsible for administering certification schemes, such as the ABCB for the WaterMark Certification Scheme.

Encompasses all government bodies, including local councils and state entities like the EPA or Sydney Water.

Water supplied from diverse sources such as stormwater, recycled water, and desalination as an alternative to conventional dams.

An attribute contributing to the health, physical independence, comfort, and well-being of people.

The probability that a given rainfall total accumulated over a given duration will be exceeded in any one year.

The theoretical amount of greenhouse gas emissions attributable to building services energy use.

The relevant authority, such as a local council or building certifier, with statutory responsibility to determine compliance.

The process by which a taskforce or authority judges the value or quality of a product or approach.

A method used to determine if a Performance Solution or Deemed-to-Satisfy Solution complies with Performance Requirements.

The national guideline document for flood estimation and hydrological design in Australia.

A national guideline providing best practice information for managing urban stormwater quality and WSUD.

The average time period between occurrences equalling or exceeding a given value (largely superseded by AEP in ARR 2019).

A mechanical device or air gap designed to prevent the unplanned reversal of flow of contaminants into a water supply.

A reversal of water flow caused by downstream pressure exceeding supply pressure.

The portion of streamflow sustained by groundwater discharge between rainfall events.

A vegetated system, such as a rain garden, that filters stormwater through soil media and plants to remove pollutants.

Wastewater and sewage from toilets; requires intensive treatment for reuse.

An obstruction within a water service or sanitary plumbing and drainage system.

A rainwater tank that is set into and completely covered by earth.

A metric used to compare emissions from various greenhouse gases based on their global warming potential.

The topographically defined area of land that drains to a particular point along a waterway or into a stormwater system.

Managing stormwater at a catchment scale to address cumulative impacts of urban development.

A certificate issued by a state authority stating that a material or method fulfills specific NCC requirements.

A certificate issued under an ABCB scheme affirming that a product or system complies with NCC standards.

An entity accredited by JAS-ANZ to certify materials, products, or management systems.

The fluctuations in climate patterns, such as drought and intense rainfall, that must be considered in WSUD design.

Involving the community in planning and maintenance of water projects to foster support.

Man-made systems using vegetation and varied water depths to settle, filter, and biologically treat stormwater.

Barriers built across waterways to store water; increasingly supplemented by rainfall-independent sources.

Prescriptive provisions in the NCC which are formally deemed to satisfy the mandatory Performance Requirements.

A method of satisfying the NCC by adhering strictly to Deemed-to-Satisfy Provisions.

The flood event selected by an appropriate authority for the management of flood hazard at a specific location.

The flood level associated with a defined flood event relative to a specified datum.

Specific requirements for the design and construction of WSUD measures based on local and national regulations.

A report required under SQIDEP following the completion of field testing for a treatment device.

Legal approval for development as defined in state legislation, such as the NSW Environmental Planning and Assessment Act 1979.

Any part of a sanitary drainage system, liquid trade waste drainage, or stormwater drainage system.

Greenhouse gas emissions arising in the supply chain of materials, from extraction to delivery to a site.

A level of water demand that can be supplied confidently and indefinitely, irrespective of drought duration and intensity.

A level of health, safety, or amenity provided by a Performance Solution that is at least equal to the DTS Provisions.

The wearing away of soil and rock by water flow, which stormwater systems aim to control.

The testing and verification of approaches and outcomes against defined success factors.

Documentary evidence, such as test reports or certificates, used to prove a material or design meets NCC requirements.

The judgement of a person with the qualifications and experience to determine if a solution complies with the NCC.

The initial portion of stormwater runoff, typically containing the highest concentration of surface pollutants.

Land lower than the flood hazard level which has been determined by the appropriate authority.

The flood level used to determine building floor heights, representing the defined flood level plus freeboard.

The inundation of land by water, often caused by heavy rainfall or overflowing waterways.

The height added to a defined flood level to compensate for effects like wave action and localized hydraulic behaviour.

A building sustainability rating scheme managed by the Green Building Council of Australia.

Wastewater from sinks, showers, and baths (excluding toilets) that can be treated for non-drinking uses.

A primary treatment device designed to capture large pollutants like litter and debris from stormwater runoff.

Water located below the land surface in rock gaps and sediments.

The process of surface water entering the soil.

A holistic approach considering the entire water cycle, including stormwater, drinking water, and wastewater.

The Joint Accreditation System of Australia and New Zealand, responsible for accrediting certification bodies.

The local government body responsible for managing stormwater within its specific jurisdiction.

Physical damage, financial loss, or loss of amenity caused by failure of a plumbing or drainage system.

An area with a 5-minute rainfall intensity (for a 5% AEP) of not more than 125 mm/hour.

Ongoing activities required to ensure the continued proper functioning of stormwater and WSUD assets.

Model for Urban Stormwater Improvement Conceptualisation; software used to model the performance of stormwater treatment trains.

The authority responsible for accrediting testing laboratories and ensuring accurate data for evidence of suitability.

Trees, shrubs, and grasses naturally occurring in an area, as defined in the NSW Biodiversity Conservation Act 2016.

A person or entity who is the operator of a stormwater drainage system.

The primary set of technical provisions for the design and construction of buildings and structures in Australia.

Water not intended for human consumption, often sourced from recycled water or stormwater.

A system that treats wastewater generated on-site and discharges effluent to an approved reuse or disposal system.

Greenhouse gas emissions arising from the ongoing operation of building services, such as HVAC and pumps.

A device providing relief to a system to avoid uncontrolled discharge during high-flow events.

A rainwater tank that is set into the ground but not completely covered by earth.

A mandatory NCC requirement stating the level of performance a building or system must meet.

A method of complying with Performance Requirements other than by using a Deemed-to-Satisfy Solution.

A report defining the scope, technical basis, and acceptance criteria for a proposed Performance Solution.

Paving materials that allow rainwater to pass through and infiltrate the ground, reducing runoff.

Volume Three of the NCC, which contains technical provisions for plumbing and drainage systems.

The point where an on-site stormwater system connects to a Network Utility Operator's system.

Water intended for human consumption that meets Australian Drinking Water Guidelines.

A treatment stage targeting large gross pollutants and coarse sediments through screening or sedimentation.

Documentary evidence detailing the characteristics and compliance merits of a particular product or system.

A registered engineer with the appropriate expertise to certify designs or solutions under the NCC.

Wastewater purified to meet strict guidelines for supplementation of drinking water supplies.

A plan submitted for approval prior to the commencement of field testing under the SQIDEP protocol.

Water sources not dependent on rain, such as seawater desalination and recycled wastewater.

A water service distributing water from a rainwater storage to points of discharge.

A vessel, such as a tank, used to collect and store roofwater for reuse.

The probability that a system or component performs consistent with its specifications.

Energy derived from regenerated sources such as solar, wind, or wave power.

A high-emissions climate scenario used to model future infrastructure resilience.

A water supply capable of withstanding or recovering from difficult conditions like intense drought.

The portion of rainfall that flows over land into stormwater systems after environmental losses.

A process where seawater is treated to remove salts to create drinking water.

A treatment stage targeting fine sediments and attached pollutants through enhanced sedimentation or filtration.

The amount of water expected to meet community needs during a severe drought.

Stormwater Quality Improvement Device; a device used to remove pollutants from stormwater runoff.

The national evaluation protocol for independently verifying the performance of proprietary stormwater treatment devices.

Naturally occurring freshwater found in rivers, lakes, and reservoirs, or resulting from rainfall runoff.

A shallow, vegetated channel designed to convey and treat runoff through infiltration and plant-induced friction.

A treatment stage targeting dissolved pollutants and nutrients through biological uptake and fine filtration.

A measure of the small solid particles that remain in water, used as an indicator of water quality.

The strategic sequencing of multiple treatment devices to optimize the removal of varied pollutants.

The unintentional release of fluid from a plumbing or drainage system, such as seepage or leakage.

The process of providing evidence to support the accuracy and reliability of results or compliance.

Measurable goals for receiving water quality, often expressed as pollutant reduction targets.

An approach that integrates urban water cycle management into planning to reduce pollution and flood risks.

Statutory rules defining how water is allocated between environmental needs and community users.

Physical infrastructure implemented as part of WSUD, such as swales, rain gardens, and wetlands.