Flood Risk Assessment: Introduction to flood risk and water managment Flashcards
Flood risk = Flood ______ × Consequences
Probability
Name two key reasons flood management is important.
- High fatalities (e.g. China 1931)
- Rising economic damages (e.g. UK 2007: £3B)
True/False
Flash floods kill more people per year in the USA than any other natural disaster.
True
What is flood risk?
The product of the probability of flood occurrence and the consequences of flooding.
Hazard →
Vulnerability →
Risk →
- probability of flood
- consequences of flood
- hazard × vulnerability
What are the two types of flood data series used in statistical analysis?
Peaks over threshold (POT) and annual maximum series (AMS)
Statistical approach →
Simulation approach →
- Flood frequency curve
- Rainfall-runoff models
Evaluating economic risk involves linking stage–discharge curves to ________ functions.
Damage
Risk Types
Health risk →
Social risk →
Environmental risk →
- Disease, injury
- Stress, community impacts
- Contamination, biodiversity loss
Types of Floods
Fluvial →
Pluvial →
Coastal →
Flash →
Groundwater →
Dam failure →
- river floods
- surface runoff due to overwhelmed drainage
- storm surge, tides
- sudden intense rainfall
- rising water table
- catastrophic infrastructure failure
True/False
Groundwater floods are more likely in areas underlain by impermeable rock.
False (they occur in permeable rock areas like chalk)
Name two organisations managing UK flood risk.
DEFRA and the Environment Agency
The Flood and Water Management Act aims to manage risk and protect ____.
water supplies
Flood Risk Management Cycle
Prevention & Preparation →
Response →
Recovery →
- land use, awareness
- evacuation, defence
- reconstruction, analysis
What is Natural Flood Management?
Use of natural processes to reduce flood risk (e.g. restoring rivers, soil infiltration, salt marshes)
UK catchment water planning occurs across ___ river basin districts.
11
Integrated Water Management
Water utilities →
Local authorities →
EA →
- regional planning
- surface water plans
- catchment planning
Why is a systems approach needed for water management?
To coordinate planning and reduce unintended impacts across multiple scales
True/False
CityWat simulates stormwater and drinking water supply but not river quality.
False (it includes river quality)
Wet periods (driver of river quality) →
Dry periods (driver of pollution) →
agricultural pollution
urban wastewater pollution
What does WSIMOD help assess in planning scenarios?
Flood risk, water quality, groundwater storage, and baseflow
