Tutorial
ed cost of securing and delivering additional potable supplies
in lieu of reclaimed water — then it typically becomes evident
that the utility and the community are better off financially
(and often environmentally and socially, too) by investing in
water reuse, because the overall benefits often do outweigh
the costs.
The TBL approach is also useful where some options
empirically robust forms. For example, in some applications the results are only described qualitatively. There also
are practitioners who apply subjective scores and weights
to outcomes and cast these subjective rankings within the
three bottom lines. The qualitative and subjective scoring/
ranking approaches have some merit. However, the most
useful and sound TBL applications rely as much as possible
on objective, quantitative measures of
the benefits and costs, which can be
derived by drawing upon an array of
advanced and professionally accepted estimation approaches, including
what economists refer to as nonmarket valuation techniques. These
techniques enable suitably trained
professionals to develop valid monetary measures for impacts that are not
typically reflected directly in prices
observed from market transactions,
such as the value of improved waterbased recreation or of enhanced critical habitat for special status wildlife
(such as salmon).
Advantages To Using A
Quantitative TBL Approach
Our experience has demonstrated that
the quantitative TBL approach can be
extremely useful as a way of understanding and communicating the big
picture values of a proposed or contemplated action. This can overcome
limitations of other, less comprehensive assessment approaches.
Factoring
in
Important
Co-Benefits. Although many water
reuse programs may have costs
that outweigh anticipated revenues
(because recycled water is often sold
at rates that do not recover full costs),
we have applied the TBL approach to
clearly demonstrate that when examining the broader perspective of utility- and community-wide impacts as
a whole, the benefits often greatly
outweigh the costs. In other words,
various factors (such as discounted
pricing of reclaimed water) can make
a water reuse program appear to be
an unwise financial investment when
examined in isolation and focusing
only on revenues and costs. But when
the broader water sector implications
are considered — including the avoidwateronline.com
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Water Online The Magazine
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