Glossary
A quick guide to the terms we use throughout this site.
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As you explore our work, you’ll come across words and concepts that might be new or used in a specific way.
Use this glossary to look up definitions, better understand our approach, and get more context behind what we do.
A
Adaptive Management
A restoration approach where decisions are adjusted over time based on monitoring results and changing environmental conditions.
Aerobic
A term used to describe conditions, organisms, or processes that require oxygen. For example, many aquatic species and natural processes depend on oxygen to function properly.
Algae
A group of mostly aquatic organisms that contain chlorophyll and can produce their own food through photosynthesis. Unlike plants, algae do not have true roots, stems, or leaves, and can range from tiny single cells to large forms like seaweed and kelp.
Anaerobic
A term used to describe conditions, organisms, or processes that occur without oxygen. Some organisms are able to survive and function in low or no-oxygen environments.
Aquaculture
The farming and harvesting of aquatic plants and animals, such as fish, shellfish, and seaweed, in controlled environments.
Aquatic Bench
A shallow, flat area just below the surface of the water where wetland plants grow and provide habitat for fish and insects.
Aquatic Habitat
The natural environment where fish and other aquatic species live, feed, and reproduce.
B
Bank Stabilization
Techniques used to prevent erosion along stream or river edges, often using vegetation, logs, rocks, or bioengineering structures.
Beaver Dam
A structure built by beavers using branches and mud. Beaver dams slow water, create ponds, and increase wetland habitat.
Baseflow
The steady flow of water in a stream that comes from groundwater, especially during dry periods. Baseflow helps keep streams cool and flowing even when there is no rain.
Baseline Monitoring
Measurements taken before a project begins to understand existing conditions such as water quality, fish presence, or vegetation.
Benthic Invertebrates
Small organisms that live at the bottom of streams and rivers, such as insect larvae, worms, and snails. They are an important food source for fish.
Biodiversity
The variety of living organisms within an area, including plants, animals, fungi, and microorganisms.
Bioengineering
Using living plant materials (such as willow cuttings) to stabilize soil, reduce erosion, and improve habitat.
Biota
All living organisms found in a particular area, including plants, animals, fungi, and microorganisms.
Buffer (Riparian Buffer)
A vegetated area located between land and a waterbody, such as a stream, wetland, or lake. Buffers help slow and filter runoff, reducing the amount of pollutants that reach the water.
C
Channel (Stream or River Channel)
The physical path where water flows. Channels can be natural or constructed during restoration projects.
Climate Resilience
The ability of an ecosystem or community to recover and adapt to the impacts of climate change, like floods, droughts, or heat waves.
Connectivity
The degree to which rivers, streams, and wetlands are linked, allowing fish and wildlife to move freely and maintain healthy populations.
Connectivity (Fish Passage)
The ability for fish to move freely through streams, rivers, and wetlands without barriers like dams, debris, or disconnected channels.
Conservation
Actions that protect, restore, and sustain natural ecosystems for long-term environmental health.
Contouring
Shaping land to improve water flow, create habitat, or stabilize slopes. Often used during restoration of gravel pits or wetlands.
Critical Habitat
Habitat that is necessary for the survival or recovery of a species listed under Canada’s Species at Risk Act (SARA). These areas are legally identified and may require protection or specific management to support the species.
Culvert
A pipe or tunnel that carries water under a road or trail. Poorly designed culverts can block fish passage.
D
Debris
Natural or human-made materials in waterways. Natural debris like logs can create habitat, but garbage harms ecosystems.
Debris Jam
A natural accumulation of logs and woody material in a stream that can create habitat complexity and shelter for fish.
Decomposition
The natural process where plants and animals break down over time and return nutrients back into the environment.
Dissolved Oxygen (DO)
The amount of oxygen in the water. Fish need high levels of dissolved oxygen to survive.
Disturbances (Natural and Human)
Events that change or disrupt an ecosystem. Natural disturbances include floods, storms, or wildfires, while human disturbances include development, pollution, or land clearing.
Drawdown
The lowering of water levels in a wetland, pit, or reservoir, either seasonally or through natural flow changes.
E
Ecosystem
A community of living things interacting with their environment: for example, a stream, wetland, or forest.
Endemic
A species that is found only in one specific area and nowhere else in the world.
Erosion
The wearing away of soil by water, wind, or human activity. Erosion can damage streams and fish habitat.
Estuary
The area where freshwater meets saltwater, such as where the Fraser River meets the ocean. Estuaries are critical nurseries for salmon.
Extinct Species
A species that no longer exists anywhere in the world.
Extirpated Species
A species that no longer exists in a specific area but still exists in other parts of the world.
F
Freshet
The seasonal rise in water levels, usually in spring when snow melts. Freshet can wash fish into floodplain wetlands like gravel pits.
Fragmentation (Habitat Fragmentation)
When a natural area is broken into smaller, separated pieces, often by roads, development, or other human activities. This can make it harder for wildlife to move, find food, and survive.
Floodplain
Low-lying land along a river that naturally floods during high water. Floodplains absorb water, reduce flooding, and provide habitat.
G
Greenway
A natural or protected corridor, often along rivers, trails, or open spaces, that connects habitats and allows people and wildlife to move through the landscape.
Groundwater
Water stored beneath the earth’s surface in soil or rock. Many streams rely on groundwater to stay cool in summer.
H
Habitat
The natural environment where a plant or animal lives, including the food, water, shelter, and space it needs to survive.
Headwaters
The source area of a stream or river, where water first begins to flow. Headwaters are often small, cool, and sensitive, and play a critical role in supporting downstream ecosystems.
Hydrology
The study of how water moves above and below the ground.
I
Impervious Surfaces
Surfaces like roads, rooftops, and parking lots that do not allow water to soak into the ground. Instead, water flows over them as runoff, which can carry pollution into streams and rivers.
Indigenous Plants
Plants that naturally occur in a specific region and have evolved alongside local ecosystems. These plants support wildlife and strengthen habitat resilience.
(Replacing the term “native plants,” per your language preference.)
Intermittent Stream
A stream that only flows during certain times of the year, usually after rainfall or snowmelt, and may dry up at other times.
Invasive Species
Plants or animals that are not naturally part of an ecosystem and spread aggressively, outcompeting indigenous species.
J
K
L
Land Use
How land is used or managed by people, such as for agriculture, housing, industry, or conservation. Land use decisions can directly affect water quality and ecosystem health.
M
Meander
A natural curve or bend in a river or stream, formed over time as water flows and shapes the landscape.
Mitigation
Actions taken to reduce, prevent, or offset negative impacts on the environment.
Monitoring
The ongoing process of collecting data to track environmental conditions, such as water quality, wildlife, or habitat health over time.
N
Non-native Species
A plant or animal that has been introduced to an area where it does not naturally occur. Some exotic species can become invasive.
Nutrients
Substances like nitrogen and phosphorus that help plants grow. Too many nutrients in water can lead to problems like excessive algae growth.
Nutrient Management
Practices used to control the amount of nutrients entering the environment, especially water systems, to prevent pollution and maintain ecosystem health.
O
Off-Channel Habitat
Calm, slow-moving water areas connected to a main river where juvenile salmon rest and feed.
Overwintering Habitat
A place where fish and wildlife can survive through winter, often requiring deep, cool, stable water and shelter.
P
Pathogen
A microorganism, such as bacteria or viruses, that can cause disease in humans, animals, or plants.
Perennial Stream
A stream that flows year-round, supported by groundwater or consistent water sources.
Pesticides
Chemicals used to control pests, such as insects or weeds. If not managed properly, they can enter waterways and harm wildlife and water quality.
Q
R
Rain Garden
A planted depression that collects and absorbs rainwater runoff, improving water quality and reducing flooding.
Rearing Habitat
Areas where juvenile fish grow and feed, such as wetlands, side channels, and slow streams.
Riparian Area
The transition zone between land and water. The vegetated edges along streams, rivers, wetlands, and lakes. Riparian plants provide shade, stabilize banks, and support wildlife.
River Basin
A large area of land where all water drains into the same major river system. A watershed is part of a river basin, and multiple watersheds can make up a single basin.
Runoff
Water from rain or snowmelt that flows across land into streams.
S
Sediment
Soil, sand, and gravel carried by water. Too much sediment can harm fish and degrade streams.
Side Channel
A smaller, slower branch of a river that provides calm water and rich habitat for juvenile fish.
Spawning Channel
A constructed or natural channel where salmon lay their eggs. Channels are designed with cool, flowing, oxygen-rich water and suitable gravel.
Species at Risk
Plants or animals that are in danger of disappearing. In Canada, these species are identified under the Species at Risk Act (SARA) and may be listed as endangered, threatened, or of special concern.
Spillway / Overflow Channel
A controlled pathway that allows excess water to safely exit a wetland or pit during high flows (like freshet).
Streambank
The land alongside a stream or river. Healthy streambanks prevent erosion and provide habitat.
Sub-watershed
A smaller section of a larger watershed. Each sub-watershed contributes water to the main river system and can have its own unique characteristics and challenges.
T
Turbidity
How cloudy water is. High turbidity means more suspended particles and can stress fish.
U
V
W
Watershed
A watershed is an area of land that acts like a connected system, where all water, whether it falls as rain or snow, travels across the landscape and drains into the same river, lake, or stream. Along the way, it carries everything with it, from soil and nutrients to pollution, meaning that what happens on the land directly affects the water.
Wetland
A water-rich area supporting specialized plants and wildlife, such as marshes, bogs, and swamps.
X
Y
Z