Sample Processing - Waterborne Pathogens: Detection Methods and Applications - page 67

WFD monitoring requirements
for surveillance, operational &
investigative monitoring

WFD monitoring tasks

Hypotheses:
define the question that monitoring needs
to answer & monitoring objectives

Monitoring design
e.g. where, when &
how often

Grouping of water bodies

Environmental variability

Selection of monitoring tools
e.g. with a certain
measurement uncertainty

Type & number of indicators
with a certain precision
confidence & robustness

Level of precision & confidence

Feasibility
&
cost

Answer

+ associated level of risk

Decision

Figure 4.1 Framework and parameters that need to be considered for successful
implementation of biological and chemical monitoring under the Water Framework
Directive (WFD) of the European Union (EU). Source: Overview for Figure 1 from Ref. 14 .

variations in pathogen concentration. Monitoring of raw water sources
is commonly done through grab sampling at different points, collecting
perhaps 10 L. Cryptosporidium testing, with the USEPA 1623 method,
described in the previous Chapter is an example of sampling over time,
where 1000 L of finished drinking water is filtered over 24 h before being
subjected to further analysis. Both of the above methods provide batch
samples.