Chemical status is assessed from compliance with environmental standards for
chemicals that are priority substances and/or priority hazardous substances.
Table 3.4 presents the list of priority substances for chemical status adapted from
Environmental Quality Standards Directive (2008/105/EC). Chemical status is
recorded as ‘good’ or ‘fail’. Chemical status for a water body is determined by the
worst scoring chemical (one-out-all-out approach). The priority substances were
monitored only in water bodies where there are known discharges of these pollutants. Water bodies without discharges of priority substances are reported as being at
good chemical status.
Ecological status classification consists of four different types of assessments:
1. An assessment of status indicated by a biological quality element, such as fish,
invertebrates, or algae
2. An assessment of compliance with environmental standards for supporting
physico-chemical conditions, such as dissolved oxygen, phosphorus, and
ammonia
3. An assessment of compliance with environmental standards for concentrations of
specific pollutants, such as zinc, cypermethrin, or arsenic and in determining high
status only
4. A series of tests to make sure that hydromorphology is largely undisturbed and
Tables 3.5 and 3.6 illustrate the biological and chemical quality elements,
respectively.
Based on WFD, ecological status is recorded as high, good, moderate, poor, or
bad. ‘High’ represents “largely undisturbed conditions”. Figure 3.1 shows a diagram
for the summary of classification.
1.3 Water Quality Indices (WQIs)
Water quality assessment can be defined as the evaluation of the physical, chemical,
and biological nature of water in relation to natural quality, human effects, and
intended uses. Water quality indices (WQIs) can be defined as the translation of
numerical values of several water quality characteristics of a sample into a single
value used in the monitoring, comparison, and control of water quality [16]. WQIs
reduce a great amount of parameters to a simpler expression to enable easier
interpretation of the monitoring data.
The concept of WQIs has been reported in Germany in 1848 (the presence or
absence of certain organisms in water was used as the indicator) [17]. A wide range
of WQIs has been developed and applied to classify the quality of water in different
regions. Traditionally, most of these WQIs were introduced to deal with data from
different manual and automated sampling networks and monitoring programs.
WQIs can be classified into three categories: hysic-chemical, biological, and
hydro-morphological WQIs, as shown in Table 3.2. A large number of WQIs has
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H. A. Aziz et al.
chemicals that are priority substances and/or priority hazardous substances.
Table 3.4 presents the list of priority substances for chemical status adapted from
Environmental Quality Standards Directive (2008/105/EC). Chemical status is
recorded as ‘good’ or ‘fail’. Chemical status for a water body is determined by the
worst scoring chemical (one-out-all-out approach). The priority substances were
monitored only in water bodies where there are known discharges of these pollutants. Water bodies without discharges of priority substances are reported as being at
good chemical status.
Ecological status classification consists of four different types of assessments:
1. An assessment of status indicated by a biological quality element, such as fish,
invertebrates, or algae
2. An assessment of compliance with environmental standards for supporting
physico-chemical conditions, such as dissolved oxygen, phosphorus, and
ammonia
3. An assessment of compliance with environmental standards for concentrations of
specific pollutants, such as zinc, cypermethrin, or arsenic and in determining high
status only
4. A series of tests to make sure that hydromorphology is largely undisturbed and
Tables 3.5 and 3.6 illustrate the biological and chemical quality elements,
respectively.
Based on WFD, ecological status is recorded as high, good, moderate, poor, or
bad. ‘High’ represents “largely undisturbed conditions”. Figure 3.1 shows a diagram
for the summary of classification.
1.3 Water Quality Indices (WQIs)
Water quality assessment can be defined as the evaluation of the physical, chemical,
and biological nature of water in relation to natural quality, human effects, and
intended uses. Water quality indices (WQIs) can be defined as the translation of
numerical values of several water quality characteristics of a sample into a single
value used in the monitoring, comparison, and control of water quality [16]. WQIs
reduce a great amount of parameters to a simpler expression to enable easier
interpretation of the monitoring data.
The concept of WQIs has been reported in Germany in 1848 (the presence or
absence of certain organisms in water was used as the indicator) [17]. A wide range
of WQIs has been developed and applied to classify the quality of water in different
regions. Traditionally, most of these WQIs were introduced to deal with data from
different manual and automated sampling networks and monitoring programs.
WQIs can be classified into three categories: hysic-chemical, biological, and
hydro-morphological WQIs, as shown in Table 3.2. A large number of WQIs has
72
H. A. Aziz et al.