Introduction

The DRAPT has currently been applied to 143 dams across Nghe An and Ha Tinh Provinces. Preliminary risk assessments and indicative flood inundation maps have been prepared for all 143 dams.

In addition the project has conducted a number of training courses and workshops for key project stakeholders in both project provinces.

Viet Nam now has a methodology to deliver evidence-based decision making for upgrading dams and improving community based disaster risk management. Anyone interested in finding out more about the application of the DRAPT

DRAPT Methodology

The DRAPT involves the five steps summarised below. The steps are:

  •  Step 1:   Dam site inspection
  •  Step 2:   Preliminary downstream impact assessment
  •   Step 3:   Preliminary spillway capacity assessment
  •   Step 4:   Preliminary potential failure modes assessment
  •   Step 5:   Preliminary dam safety risk assessment

These five steps provide a meaningful estimate of both the probability of dam failure (Steps 1, 3 and 4 combined) and the consequences of dam failure (Step 2). This information is combined in Step 5 to provide an understanding of the overall risk of the dam.

When the DRAPT is applied across a large number of dams (for example within a catchment, province or district) the relative risk between dams can be understood. The dams can then be ranked in order of risk (prioritised).

The DRAPT uses existing data and limited analytical methods to provide a preliminary understanding of the risk of an existing dam. As a result, the outputs from the DRAPT are indicative and appropriate only for a preliminary assessment. More detailed studies or investigations to better understand a dams performance and confirm the risk may be required. Such investigations are outlined in the DDCSI (2015) report entitled “Dam and Downstream Community Safety Initiative: Guidelines”.

The DRAPT is currently only developed for embankment and concrete dams and is not applicable to other types of dams. Like any analytical tool the DRAPT is subject to limitations. The user of the DRAPT shall understand these limitations and have adequate training before using the DRAPT.