Banchini, Giovanni 
  
ROLE OF DIGITAL ORTHOPHOTOS IN ENVIRONMENTAL DISASTER MANAGEMENT 
G. Banchini, L. Ferretti, G. Lombardo, L. Surace, 
Compagnia Generale Ripreseaeree (CGR),Parma,Italy 
KEY WORDS: Photogrammetry, aerial photography, orthophoto, digital orthophoto, hazards, disaster planning 
ABSTRACT 
Recurrent disasters that affect densely populated areas subject to high geologic risks are primarily conditioned 
by the frequency of occurrence of natural events and by the morphology and structure of the landscape but a prominent 
cause of the resulting damages is the dishomogeneous and ill structured geographic information available which 
influences also the mechanism of reaction to the event. An effective defense against natural or man-made disasters 
always includes a phase of acquisition and updating of environmental information. The knowledge acquired must be 
reliable, homogeneous and up to date. But in addition to addressing the natural phenomena that may bring on the 
disasters, the information should be capable of addressing also the available resources to plan effectively protective 
measures and to make rapid decisions in emergency conditions. 
The color digital orthophoto, now routinely operational, constitutes today the most effective and economical 
instrument for studying risks before the occurrence of the disasters: as a georeferenced tool and as a connective link for 
emergency planning. 
The paper describes a general model of environmental information by semicontinuous monitoring of large 
areas at risk using the 1998 Sarno landslide events of southern Italy as an example. The model proposes to standardize, 
within a quality control system, the management process relative to the situation prior to the event, the phases 
immediately after the occurrence of the disaster and the planning of post- disaster operations including the estimate of 
damages up to the normalization phase. 
INTRODUCTION 
The recurring hydrogeologic hazards that plague Italy are brought about by the geologic fragility of the 
landscape and induced by natural events such as intensive rains and earthquakes. But among the background causative 
factors of the costs associated with the hazards is the non homogeneous and ill organized land use and resource 
information available as well as the cause and effect mechanisms related to the human pressure on the environment. 
Among the human causes one must list urban spread over geologically weak areas, encroachment on flood plains and 
the covering up of stream channels and soil with concrete not to mention the general flight of agriculture from hillsides 
and the accelerated deforestation. The actions have come about not only out of environmental ignorance but also out of 
speculative and even illegal planning. 
An effective defense against natural or man induced environmental disasters, always implies, prior to making 
decisions about protection measures, a phase of acquisition and updating of geographic information . The information 
we have and that which is acquired in time needs to be organized in appropriate data banks, efficiently built and 
maintained and programmed to be easily accessible and properly centered in their most significant aspects to meet the 
needs that present themselves from time to time. In this phase of acquisition and archiving of the environmental 
information, the role of cartography is preeminent in a general way as the basic platform for georeferencing events. Just 
as important is the function of cartography to assist in the evaluation of preventive measures. These measures are 
normally classified as “structural” and “non structural” where the first are those that control the risk factors by 
modifications of the landscape to diminish the risk or to protect against it. Because it is not possible to protect 
everything against any type and level of risk it is important that the structural measures be planned adequately within 
the available resources. 
The economics aspect of the environmental risk problem make worthwhile an increase in the non structural 
interventions on the landscape. It may be developed along these lines: 
Stress land use planning accompanied by appropriate legislation directed to and to be strictly enforced by the 
Public and Private Administration particularly as it concerns the control of new constructions. 
  
106 International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B7. Amsterdam 2000.