Decision support tool

Control measures

Control measures for different hazards often already exist, possibly including ones for cyanotoxins, such as the reduction of nutrient input into a water body or the display of warnings of bathers.

Cyanotoxins can be controlled most efficiently by an overall concept, the basis of which is an optimized management of the catchment and the water body. Depending on the actual abundance of cyanobacteria, it may also comprise optimization of the drinking water abstraction and treatment processes or warning and information of the public if the water body is used for recreation.

Assessment of existing measures to control the cyanotoxin risk is usually already performed during system assessment, and, if necessary, improvement of the measures should be developed. If existing measures are insufficient, the WSP-team should develop and propose additional measures.

Each measure should be documented in a WSP to include:

  • The reasons for the choice of measure, and quality assessment of the data and information available (e.g. document gaps in knowledge),
  • The targets to be achieved
  • The steps taken for validation
  • The operational monitoring of the measures (e.g. setting of operational limits for turbidity)

Furthermore, a management plan should define which corrective actions should be taken if operational monitoring indicates poor performance or if incidents occur, and how the monitoring of operational limits is documented.

Catchment and lake management usually involves a number of different stakeholders with potentially conflicting interests. Success in the implementation of control measures therefore is more likely if all stakeholders are involved in the decision-making on control measures (e.g. within the WSP-team).