Effect: Raises Temperature, lower O2, kills fish

Risk: Low, well regulated by the Integrated Pollution Prevention and control directive.

Measurement: DO, T, upstream/downstream, sampling every hour

Effect: can change ph of water, add toxic chemicals to water, kills fish

Risk: medium, rules of dilution of polluting water but not strict enough to prevent pollution

Measurement: measure ph levels and take samples of upstream compared to downstream pollution levels

Effect :increases nutrients like nitrates in water leads to eutrophication which in turn reduces dissolved oxygen as the algae consume it

Risk: high up to farmers to control their use

Measurement: Biochemical oxygen demand

Effect: highly toxic to aquatic life

Risk: Relatively high, not largely regulated

Measurement: upstream/downstream sampling

Can be acidifying

Kills wildlife within rivers due to higher pH

Measurement, measure pH of river and metal concentration

Effect: persistent organic pollutants, leads to bioaccumulation in the food chain

Risk: medium

Measurement: pH tests

Effect: Bacteria decomposing organic material, greatly lowers O2 and kills aquatic life

Risk: Medium to high: sewage outflows regulated by Ofwat but may still happen regularly depending on infrastructure

Measurements: DO, work out BOD

effect: big BOD leading to a reduction in DO, may lead to eutrophication and a reduction in biodiversty

Risk: High

Measurement: BOD and DO measurements, biodiversity sampling

Effect: high nitrate level

Risk: High

Measurement: upstream and downstream sampling

Effect: sheep glazing upstream can cause erosion, leading to coloration and humic change. Increased pH levels may affect biodiversity and/or kill species.

Risk: Medium, if sheep farming/glazing done strategically.

Measurement: colour, turbidity, taste, ammonia, pH

Effect: pH change, lack of buffer, reduced biodiversity, killing of sensetive species, reduced photosynthesis or increased oxygen demand, algal blooms.

Risk: High, especially if flooded or surfaced.

Measurement: colour, conductivity, BOD, DO, odour, taste, turbidity, temp, ammonia and nitrate