Expanded glossary

This page contains all definitions written inside of your teacher guide, but will be continually updated when we include new or relevant terms that students and teachers will need to know.

Acidic: having a pH lower than 7. Examples of acidic foods are lemon juice and carbonated drinks.

Algae: aquatic plant that can be very small (single celled), or very big (seaweeds). Blue-green algae, actually a form of cyanobacteria and not algae, can be toxic.

Alkalinity: a waterbody’s ability to withstand changes in pH. High alkalinity is not a sign of poor water quality.

Artificial intelligence: using computers to do complex tasks that usually require humans. These tasks can include visual interpretation, translation and making decisions.

Baseline: “normal” measurements for a water body obtained after testing a place monthly for at least 2 years.

Basic: having a pH greater than 7. Examples of basic foods are sweet potato and watermelon.

Celsius: a unit of temperature where water freezes at 0 and boils at 100.

Chlorine: a greenish-yellow, highly reactive and diatomic gas that is almost never found free in nature by itself. It is most widely known for being used within compounds to purify water and cleaning products.

Conductivity: the ionic content (such as chloride, nitrate, sulfate, sodium, magnesium, calcium, or iron) in a body of water measured as water’s ability to conduct electricity in μS/cm (microsiemens per centimetre).

Context: circumstances and information that help you understand a situation. For example, strong winds can bring sediments in the water and increase conductivity.

Data: information in the form of numbers, measurements, and visual information. Information collected through water testing becomes data when shared.

Discharge: A calculation of how much water is flowing through a particular waterbody. It’s calculated by multiplying the velocity (speed) by the surface area (width multiplied by height of the water).

Dissolved oxygen: the amount of gaseous oxygen dissolved in the water. Oxygen gets into the water in various ways, including absorbing it from the atmosphere, by rapid movement of the water, or as a product of photosynthesis.

Hardness: related to alkalinity as they both measure calcium carbonate content. It also measures other metals in the water that do not necessarily neutralize acid.

Invasive species: plants, animals and insects that were brought to a territory where they don’t usually live and have damaging effects on the local ecosystem.

Microsiemens: siemens are a unit used to measure electric conductivity. 1 microsiemens is 1 siemens divided by 1 million, and represented by μS/cm.

Open data: Data that is made accessible for everyone to see and use.

pH: it stands for “potential for Hydrogen”. It is the measure of the acidity or alkalinity of water soluble substances.

Pollution: something that causes harm to the environment, it is not naturally present.

Sewage overflow: During rain storms, storm sewers that are overloaded are discharged into lakes and rivers. These can contain diluted raw sewage.

Velocity: how we describe how fast water is flowing, usually in metres per second.