Topic 6: Investigating river processes and pressures — Edexcel GCSE Geography B
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Topic 6: Investigating river processes and pressures explained
Topic 6: Investigating river processes and pressures covers 4 specification points, including Investigating how and why drainage basin and… and Students must have an opportunity to develop….
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Open a point below for its explanation and revision guidance.
Investigating how and why drainage basin and channel characteristics influence flood risk for people and property along a river in the UK.
This statement asks you to explain how and why drainage basin and channel characteristics influence flood risk for people and property along a UK river. Basin factors such as size, shape, relief, geology, soils and land use control how quickly rainfall reaches the channel. Channel factors such as width, depth, gradient and bankfull capacity control whether water stays within the banks. Build a chain: steep, impermeable land sends rapid runoff into a narrow channel, which overtops and damages property and endangers people. Use why to state the reason each link exists. Apply the chain to a named UK river and its reach. Consider both physical causes and human exposure, such as building on the floodplain.
1. Formulating enquiry questions: Students must have an opportunity to develop understanding of the kinds of questions capable of being investigated through fieldwork in river environments. Students must have an opportunity to develop a question(s) based on their location and the task.
This statement covers formulating enquiry questions for river fieldwork. Students must understand the types of questions that can be investigated through fieldwork in river environments, and develop enquiry questions based on their chosen field location and task. An effective river enquiry question must be researchable through primary fieldwork data collection, specify measurable variables (e.g. channel width, depth, velocity, bedload size/roundness), and identify a specific river channel, reach, or comparison between sites (such as changes downstream between upper and lower reaches). For example, investigating how channel cross-sectional area changes downstream from source to mouth on a named river, or how velocity varies across a meander bend, provides a clear, measurable hypothesis linked directly to Bradshaw's model or river processes.
2. Selecting fieldwork methods: Fieldwork data collection must include at least: one quantitative fieldwork method to measure changes in river channel characteristics; one qualitative fieldwork method to collect data on factors that might influence flood risk.
The criterion requires fieldwork data collection to include two method types. One quantitative method must measure change in river channel characteristics and produce numbers that can be compared between sites or visits, for example channel width in metres measured with a tape. One qualitative method must collect data on factors that might influence flood risk, such as a land-use survey, annotated photographs or resident questionnaires about drainage and past flooding. The two methods answer different questions: the measurements show how the channel is changing, while the qualitative data explains the conditions that could raise flood risk. Plan both methods in advance and record units.
3. Secondary data sources: A flood risk map e.g. Environmental Agency Flood Risk map; One other source chosen by the centre.
This requirement names secondary data, which is existing data collected by others rather than by the learner. The first source is a flood risk map; the statement gives the Environmental Agency Flood Risk map as an example, and the body is the Environment Agency. The 'e.g.' means it is an example, so learners should check the map's source, date and what it shows, such as areas at risk of river flooding. The second source is one other source chosen by the centre, so it is not prescribed; learners should record its content and relevance to river flood risk. Use secondary data to support, check or extend fieldwork findings, noting limitations such as age or scale.
Your focus
- Identify at least two drainage basin and two channel characteristics that influence flood risk.
- Explain, using a causal chain, how one characteristic increases or reduces the risk of overtopping.
- Apply the explanation to a named UK river reach, referring to people or property at risk.
Show all 12 objectives
- Distinguish, with reasons, a question that fieldwork can answer from one that it cannot.
- Write a specific enquiry question about a named river location that names a measurable variable.
- Refine a broad question into one suitable for the time, equipment and site available.
- Select one quantitative fieldwork method that measures change in river channel characteristics.
- Select one qualitative fieldwork method that collects data on factors influencing flood risk.
- Record measurements with correct units and explain why each chosen method suits its purpose.
- Identify a flood risk map as a secondary source and state its origin and coverage.
- Explain what a chosen secondary source shows about river flood risk.
- Evaluate one limitation of each secondary source used alongside fieldwork findings.
Topic 6: Investigating river processes and pressures exam tips
Marking Points
- Identifies specific drainage basin characteristics, such as size, shape, relief, geology or land use, and links each one to the speed or volume of runoff.
- Identifies specific channel characteristics, such as width, depth, gradient, meanders or bankfull capacity, and explains how each one affects overtopping.
- Explains how basin and channel factors interact, for example steep, impermeable land feeding a narrow channel.
- Explains why each link occurs using hydrological reasoning rather than description alone.
- Applies the explanation to a named UK river and a specific reach.
- Considers human exposure, such as housing, businesses or roads on the floodplain, as part of flood risk.
- Formulates an enquiry question that can be investigated and answered using primary river fieldwork data.
- Specifies measurable river variables (e.g. velocity, discharge, channel width, depth, sediment size) and clear sampling sites.
- Links the enquiry question to established river concepts, processes, or models (such as Bradshaw's model or downstream changes).
- Ensures the question is realistic and achievable given the field location, equipment, time, and safety constraints.
- Allows for comparisons across reaches (e.g. upper vs lower reach) or across specific river features (e.g. meander cross-sections).
- Pairs one quantitative method, such as measuring channel width with a tape measure, with a clear link to change in channel characteristics.
- Names a qualitative method, such as a land-use survey or resident questionnaire, that collects data on factors influencing flood risk.
- Gives units for each quantitative measurement, such as metres for width and depth.
- Explains why the qualitative method suits gathering flood-risk factors, such as observed land use or residents' experience of flooding.
- Shows that the two methods are distinct and that both appear in the planned data collection.
- Identifies a flood risk map as a secondary source and states its origin, date and coverage.
- Explains what the flood risk map shows about river flooding, such as areas at risk.
- Names one other secondary source chosen by the centre and states its relevance to river flood risk.
- Uses secondary data alongside fieldwork findings to support, check or extend conclusions.
- Notes a limitation of each secondary source, such as age, scale or coverage.
Examiner Tips
- 💡Plan a chain before writing: characteristic, runoff or channel process, effect on flood risk, impact on people or property.
- 💡Name your UK river and reach early in the answer so that every point stays located.
- 💡Use connectives such as because, so and therefore to show the mechanism behind each link.
- 💡Check that your enquiry question includes measurable physical variables, named river locations, and a clear testable relationship.
- 💡Ensure the scope of the question fits the available field equipment, accessible river sites, and timeframe.
- 💡Link your enquiry question to geographical theory, such as downstream changes predicted by Bradshaw's model.
- 💡Check the plan against both required clauses before finishing: one quantitative method for channel change and one qualitative method for flood-risk factors.
- 💡Name each method and state the variable it measures so the link to the criterion is visible.
- 💡Justify each method choice briefly by stating what it can and cannot show about river channels or flood risk.
- 💡State the source type, origin and date for each secondary source in your answer.
- 💡Link each source to a specific flood-risk point, such as river channel capacity or the area at risk.
- 💡Comment on limitations, such as the age of the data or the scale of the map, to show evaluation.
Common Mistakes
- Lists characteristics without stating how they influence flood risk; add the causal link to each one.
- Describes the flood event and its damage rather than the basin and channel factors that caused it; focus the answer on the causes.
- Treats flood risk as only a physical matter and ignores people and property; add the human exposure element.
- Uses a generic river without a UK location; name the river and the reach being discussed.
- Poses questions based purely on opinion or value judgements that cannot be tested through measurable fieldwork data.
- Writes questions that are too vague, lacking named measurable variables or specific river locations.
- Assumes river enquiries can only investigate a single reach; comparative questions investigating changes downstream between contrasting reaches or sites are common and valid.
- Uses two quantitative methods and no qualitative method; include a qualitative method that gathers flood-risk factors.
- Chooses a qualitative method such as a survey of opinions but does not connect it to flood risk; state which flood factor it investigates.
- Records measurements without units, so the values cannot be compared; add metres, metres per second or the relevant unit to each value.
- Treats a secondary source such as a flood map as the fieldwork method; keep it as secondary data and add a separate primary method.
- Treats the flood risk map as primary data collected by the learner; label it as secondary data collected by another body.
- Assumes the named map is the only permitted flood risk map; the 'e.g.' marks it as an example of a flood risk map.
- Lists a source without saying what it shows about flood risk; state the specific information used and its relevance.
- Presents secondary data as complete proof of flood causes; state that it supports fieldwork and may have limitations.