Glossary

B

Biodiversity/ biological diversity: Refers to the variety of life forms on Earth. This includes different species of plants, animals, and fungi.

Breaching: To make a gap in and break through a barrier, such as a wall or a bank. For example, "The river breached its banks during the flood".

C

Calderdale Flood Recovery and Resilience Programme Board: Oversees the delivery of the Calderdale Flood Action Plan, which outlines actions for recovery, resilience improvement, and risk reduction.

Canal overtopping: Flooding from the canal exceeding its normal water level.

Catchment area: The geographical area from which a river collects water.

Channel widening: Expanding river channels to prevent overflow.

Check, Clean, Dry: A practice to prevent the spread of invasive plants and animals by thoroughly checking and cleaning equipment after outdoor activities (also referred to as biosecurity).

Community resilience: Collaborating with the community to prepare for and recover from flooding.

Culvert: An underground channel or pipe that carries water.

D

Debris/trash screens: Barriers designed to prevent debris from entering watercourses or river channels.

Defence replacement/repair: Upgrading or fixing existing flood defences to either maintain or enhance protection.

E

Embankment strengthening: Reinforcing or upgrading existing embankments to improve their ability to withstand floodwaters and prevent overtopping, breaching, or erosion.

Environment Agency (EA): The EA protects and improves the environment. They help people and wildlife adapt to climate change and reduce its impacts, including flooding, drought, sea level rise and coastal erosion. The EA are one of the organisations delivering a program of work to reduce flood risk in Calderdale.

F

Fauna: Refers to the animal life found in a particular region, habitat, or geological period.

Federation of Master Builders (FMB): The UK’s largest trade association for the construction industry, promoting building standards improvement for over 75 years.

Flash flooding: Rapid and intense flooding caused by sudden heavy rainfall, often leading to dangerous situations.

Flood alert: flooding is possible.

Flood Alleviation Schemes (FAS): Projects aimed at reducing flood risk to properties, businesses, and infrastructure. Whilst the main objective is reducing flooding, they offer a wide range of additional benefits. These include environmental and ecological benefits along with economic, social and community benefits.

Flood groups: These groups work for and with residents and businesses to find ways to limit the effects of flooding. They act as a voice for communities and provide information to support flood preparedness and response.

Flood siren testing: Scheduled tests of flood sirens to ensure they function properly and can alert residents during emergencies.

Flood wardens: Local volunteers supported by the Environment Agency and Calderdale Council. They play a critical role before, during, and after flooding events by providing hands-on support to communities.

Flood warning: flooding is expected.

Floodplain: A floodplain is a generally flat area of land next to a river or stream. Floodplains are important for their rich biodiversity and fertile soils.

Flora: Refers to the plant life found in a particular region, habitat, or geological period.

Full Business Case (FBC): Is a detailed document that provides a detailed and finalised justification for a project or investment. It builds on from the SOC and OBC and is used to secure final approval and funding before the project moves into the implementation or construction phase.

G

Giant Hogweed: An invasive plant not common in Calderdale. Contains sap that makes skin sensitive to sunlight, causing burns and blisters. It poses health risks to humans.

H

Himalayan Balsam: An invasive plant that grows along riverbanks and competes with native species. Its dieback in winter leaves riverbanks exposed, increasing soil erosion and flood risk.

I

Invasive Non-Native Species (INNS): Animals or plants that have been introduced to an area where they do not naturally occur. They can be damaging to other habits.

J

Japanese Knotweed: A highly problematic invasive plant that outcompetes native species. It can grow through cracks in structures, weakening and damaging buildings, footpaths, and flood defences.

L

Leaky Dams: Structures used in natural flood management to slow water flow and reduce flood risk.

M

Main River: Main rivers are usually larger rivers and streams. The Environment Agency carries out maintenance, improvement, or construction work on main rivers to manage flood risk. The main river map shows which rivers in England are designated as ‘main rivers’.

Mill gates: Gates or sluices used in water mills to control the flow of water to power mill wheels or turbines.

N

National Federation of Builders (NFB): Represents regional contractors and small to medium-sized house builders in England and Wales.

Natural Flood Management (NFM): Managing the landscape to slow down water flow.

O

Ordinary watercourse: Every river, stream, ditch, drain, sluice, and passage through which water flows and which does not form part of a main river network. Lead local flood authorities, district councils and internal drainage boards carry out flood risk management work on ordinary watercourses.

Outline Business Case (OBC): An OBC builds on the SOC and is a detailed document to assess and justify a proposed project or investment before committing significant resources. It provides a thorough evaluation to support decision-making.

P

Peat bogs: A type of wetland made up of rotting plant material, primarily sphagnum moss, that gathers in waterlogged conditions over thousands of years. They act as carbon sinks, storing more carbon than all the world’s forests combined. This helps by keeping carbon dioxide out of the atmosphere. Peat bogs also provide habitats for a variety of rare and endangered species.

Piling: The installation of heavy stakes or posts to support the foundations of structures.

Property flood resilience (PFR): Refers to a set of modifications added to a building to lower its flood risk.

R

Rated People: An online marketplace connecting homeowners with local tradespeople.

Resilient infrastructure: Strengthening sewer systems, electricity substations, and transport routes.

Riparian owner: Refers to an individual or entity that owns land adjacent to a natural watercourse, such as a river, stream, or brook. This ownership confers certain rights and responsibilities related to the watercourse.

River and floodplain management: Strategies for managing rivers and their floodplains to regulate water flow and prevent flooding.

River levels: Information about the current water levels in rivers across Calderdale.

Riverbank erosion: The gradual wearing a way of riverbanks due to water flow, which can contribute to increased flood risk.

Runoff: When rainwater travels over the ground surface of rural or urban locations.

Run-off management: Measures to control surface water runoff, utilising natural flood management and land management techniques.

S

Severe flood warning: flooding could be a risk to life and significant disruption to communities.

Sluice: A device used to control the flow of water. It typically consists of a sliding gate that can be opened or closed to regulate water movement.

Soil and land management: Techniques to preserve soil quality, improve its ability to absorb and store water, and increase biodiversity.

Sphagnum: A moss plant, that plays a vital role in the creation of peat bogs, essential for a healthy moorland environment. Sphagnum moss can hold large amounts of water, helping to regulate water levels and reduce the risk of flooding.

Strategic Outline Case (SOC): A document used in the early stages of a project to justify the need for a proposed investment or project. It outlines the strategic context and reasoning for the project, setting the grounds for more detailed planning and analysis in later stages.

Strengthening defences: Projects and schemes to reduce flooding from rivers and surface water.

Subcontractor: A business that agrees to carry out work on behalf of another business. Used in the construction phase.

Surface water flooding: Occurs when heavy rainfall overwhelms drainage systems, causing water to accumulate on roads, streets, and other surfaces.

Sustainable drainage systems (SuDS): Designed to manage rainwater in urban areas in an environmentally friendly way, SuDS capture and utilise rainwater for plants, reducing the amount of water entering sewers, which reduces the frequency of sewers overflowing into rivers.

U

Unique landscape: Calderdale’s distinctive terrain makes it particularly vulnerable to floods.

Upstream storage: Creating storage areas to hold excess water during heavy rainfall, reducing downstream flood risk.

Urban drainage: The system of drains, pipes, and channels that manage rainwater runoff in urban areas. Urban drainage helps prevent surface water flooding.

W

Weir: A low barrier built across a river to alter water flow.

Woodland management: Removal or management of selected trees from within a woodland to create a healthier woodland.