4.4.8—Eutrophication management levels
- Syllabus
- First assessment 2026
- Objective
- 4.4.8
- Level
- SL
Manage before, at and after Release
Pollution control can prevent the activity, intercept the release, or repair legacy damage; the best package uses the level that matches the pathway.
Level 1 reduces pollutant-producing activity, such as changing fertilizer or detergent use. Level 2 limits release through buffer strips, sewer repair or nutrient-removing wastewater treatment. Level 3 removes legacy pollution and restores the ecosystem, for example by removing nutrient-rich mud and reintroducing plant or fish species.
Reducing fertilizer at the field is prevention; a buffer strip intercepts runoff; dredging nutrient-rich sediment treats the legacy.
Continuing upstream input can refill the system; pair release control with source reduction.
A visible cleanup is not always the highest-leverage intervention; diagnose the source first.