Glossary/water dictionary

Alphabetical     Full list     References

nephelometric turbidity unit (NTU)

Unit of measure for the turbidity of water. Essentially, a measure of the cloudiness of water as measured by a nephelometer. Turbidity is based on the amount of light that is reflected off particles in the water.^

non-beneficial consumptive use

The water consumed by native vegetation, evaporated from bare and idle land surfaces and from water surfaces.^

non-point source (NPS) pollution

Pollution discharged over a wide land area, not from one specific location. These are forms of diffuse pollution caused by sediment, nutrients, organic and toxic substances originating from land-use activities, which are carried to lakes and streams by surface runoff. Non-point source pollution is contamination that occurs when rainwater, snowmelt, or irrigation washes off plowed fields, city streets or suburban backyards. As this runoff moves across the land surface, it picks up soil particles and pollutants, such as nutrients and pesticides.^

non-renewable resource

Those resources which do not regenerate themselves or maintain a sustained yield after being utilised or destroyed.^