Environmental Engineering Reference
In-Depth Information
Modelling Concepts and
Strategies to Support Integrated Flood
Risk Management in Large, Lowland
Basins: Río Salado Basin, Argentina
22
RODO ARADAS, COLIN R. THORNE AND NIGEL WRIGHT
Introduction
can be widely observed in flood risk management
projects in developing countries where funding
agencies ensure that there are clear rules to sup-
port where their capital loans are being invested;
the Storm Drainage Master Plan for Buenos Aires
(Halcrow et al. 2001) and the Integrated Master
Plan for the R´o Salado Catchment (Halcrow
Group 1999) are two recent examples of World
Bank-funded projects for developing flood man-
agement plans for urban and rural areas, respec-
tively, withinwhich the terms of reference express
the aspiration for integrated and sustainable
approaches. The challenge remains, however, to
develop methodologies that are adequate to
address the underlying issues within inevitable
constraints of cost, time and data availability.
The concept of sustainability in the decision-
making process implies the adoption of courses of
action that pay due regard to climate change,
socioeconomic development and the conse-
quences of decisions made today for future gen-
erations, which necessarily implies dealing with
considerable and irreducible uncertainty. This
is manifest particularly in the case of decision-
making with respect to flood risk management
strategies, as decisions arenecessarily based on the
highly complex, interactive and highly uncertain
relationships between natural hydrological phe-
nomena, the subtle landscape attributes of the
basin and the legacies of past and present human
Our approach to modelling floods must evolve as
our knowledge of the environmental, social and
economic dimensions of flooding improves and
our appreciation of the need to account for the
uncertain impacts of climate and societal changes
on future flood risks and their management con-
tinues to grow. Integrated Catchment Planning,
Integrated Flood Risk Management and the im-
perative to conserve environmental capital
through sustainable use of land and water re-
sources have long been accepted as important
concepts by stakeholders involved in the project
planning and appraisal cycle (Gardiner 1991;
Newson 1997). Indeed, for over a decade, global
funding agencies such as the World Bank have
explicitly included these concepts in the terms of
reference they specify when procuring river basin
plans (Serageldin 1994). Increasingly, these con-
cepts are formally reflected in project appraisal
mechanisms, so that they guide both the thinking
and the practical steps by which stakeholders and
scientists make choices between the various op-
tions for water resource and flood risk manage-
ment in large basins. Application of the concepts
