2.2 Pillars: Quantity, Quality, Benefits
13
• It is relative to the required water quality norms for the objectives of the WUS.
Sometimes, these norms divide the quality weights into two states, such as,
satisfactory/unsatisfactory, suitable/unsuitable, 0.98/0.11.
• W qET is always one, and under some special conditions, such as bottled water that
goes out of the WUS, W qNR is also one.
Of course, setting weights is not easy and we will explain them more. For now,
let us present some general points regarding the weights:
• In locations with partial or no data, these two weights and quantities of WPIs can
be estimated, but with active stakeholder involvement without ignoring most of
the above points.
• Both uncertainty and sensitivity of the weights are important in setting them. For
example, a lesser sensitive weight can be set with less effort than a higher sensitive
one. This means that higher error or uncertainty in the former can still result in
better outcomes and more accurate performance than lesser uncertainty in the
latter (Loucks and Van Beek 2005).
• A WUS in a water scarce region may get a lower W bX for its inflow WPTs, if
its activity is based on high water consumption, such as, water bottling plants or
irrigation of water intensive crops.
To include both quality and beneficial attributes and their trade-offs in the performance indicators, we need the concept of Usefulness Criterion (W sX ) as defined
above and given in Eq. (2.1); but why multiplication and not summation? The reason
is that to calculate one single criterion from multiple attributes is through multiplication of the attributes, whereas the presentation of the various (possible) states of a
single attribute is through the summation of those states. In other words, the Usefulness Criterion is the product (not the sum) of the quality and beneficial attributes.
The multiplication also makes sense thinking as follows: if the benefits of a flow
of water is zero, it means that the contribution of that flow to its usefulness is also
zero no matter what its quality is. On the other hand, if the water is so polluted that
makes the flow totally improper for a particular purpose, then again its contribution
to usefulness is zero no matter what its beneficial potential is. Besides associating
W sX to WPIs of the WPTs (Table 2.1), Table 2.2 gives their aggregations.
Three points worth mentioning here. First, Table 2.2 gives the total values although
the word ‘total’ is not used. For example, Consumption gives the total consumption
of a WUS. Second, the theory in this book is water-centric (analysing from a water
perspective) and in this context the ‘level’ of management (more in Chapter 4) is
defined according to the flows considered. This means that the nine fixed WPTs
defined in Fig. 2.1 are not present at the three levels utilized in this book, viz.: macro,
meso and micro as follows:
• Macro does not consider VA and RF. It considers macro-level I, C and R.
• Meso does not consider VU and VD. It considers meso-level I, C and R.
• Micro does not consider VU, VD and R. It considers micro-level I and C.
13
• It is relative to the required water quality norms for the objectives of the WUS.
Sometimes, these norms divide the quality weights into two states, such as,
satisfactory/unsatisfactory, suitable/unsuitable, 0.98/0.11.
• W qET is always one, and under some special conditions, such as bottled water that
goes out of the WUS, W qNR is also one.
Of course, setting weights is not easy and we will explain them more. For now,
let us present some general points regarding the weights:
• In locations with partial or no data, these two weights and quantities of WPIs can
be estimated, but with active stakeholder involvement without ignoring most of
the above points.
• Both uncertainty and sensitivity of the weights are important in setting them. For
example, a lesser sensitive weight can be set with less effort than a higher sensitive
one. This means that higher error or uncertainty in the former can still result in
better outcomes and more accurate performance than lesser uncertainty in the
latter (Loucks and Van Beek 2005).
• A WUS in a water scarce region may get a lower W bX for its inflow WPTs, if
its activity is based on high water consumption, such as, water bottling plants or
irrigation of water intensive crops.
To include both quality and beneficial attributes and their trade-offs in the performance indicators, we need the concept of Usefulness Criterion (W sX ) as defined
above and given in Eq. (2.1); but why multiplication and not summation? The reason
is that to calculate one single criterion from multiple attributes is through multiplication of the attributes, whereas the presentation of the various (possible) states of a
single attribute is through the summation of those states. In other words, the Usefulness Criterion is the product (not the sum) of the quality and beneficial attributes.
The multiplication also makes sense thinking as follows: if the benefits of a flow
of water is zero, it means that the contribution of that flow to its usefulness is also
zero no matter what its quality is. On the other hand, if the water is so polluted that
makes the flow totally improper for a particular purpose, then again its contribution
to usefulness is zero no matter what its beneficial potential is. Besides associating
W sX to WPIs of the WPTs (Table 2.1), Table 2.2 gives their aggregations.
Three points worth mentioning here. First, Table 2.2 gives the total values although
the word ‘total’ is not used. For example, Consumption gives the total consumption
of a WUS. Second, the theory in this book is water-centric (analysing from a water
perspective) and in this context the ‘level’ of management (more in Chapter 4) is
defined according to the flows considered. This means that the nine fixed WPTs
defined in Fig. 2.1 are not present at the three levels utilized in this book, viz.: macro,
meso and micro as follows:
• Macro does not consider VA and RF. It considers macro-level I, C and R.
• Meso does not consider VU and VD. It considers meso-level I, C and R.
• Micro does not consider VU, VD and R. It considers micro-level I and C.