II. FLOOD LOSS REDUCTION AND REVIEW OF PAST EXPERIENCES
D. General performance of flood control projectsThe main objective of flood control projects has been to increase food grain (mainly rice) production. Since Bangladesh is an over-populated and developing country, the major concern of successive governments has been to meet the ever-growing demand for food grain. Flood control projects are expected to contribute towards this end by securing wet season crops against recurrent floods. Security provided against floods was also expected to bring more area under cultivation of HYV rice.
The impacts of flood control projects on agriculture and the economy were studied by HTSL (1992a). The study made a comprehensive review of 17 FCDI projects. The projects are representative of different hydrological regions and different types of projects. The project locations are shown in Figure 4. The study found an increase in rice output ranging from 7 per cent to 241 per cent. This increase is due to reduced flood hazard and the switch to HYVs in many cases. The highest increases were found in those projects that include an irrigation component. The economic performances of the projects are shown in Table 9.
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Source: Hunting Technical Services Ltd. 1992a
As can be seen, the Economic Internal Rate of Return (EIRR) varies from a high 96 per cent to a low of -10 per cent. All projects that had a net annual economic benefit per hectare of over Taka 2000, and were completed in four years or less, achieved EIRRs of 30 per cent or more. The seven most successful projects were all small (9,000 ha or less in gross area) and relatively simple in concept and design. Harza (1991b) evaluated 8 FCD/FCDI projects and found that all the projects provided increased protection for crops with consequent increases in agricultural production. The net benefit/investment cost (N/K) ratio for the projects varies from 0.3 to 7.7, with five projects having a N/K ratio above 1.0.
However, various regional studies carried out under FAP express reservations regarding the achievement of FCD projects. While assessing the impact of FCD projects in the north-east region, Shawinigan Lavalin (1992) reports that it is not clear whether agricultural production has increased in the region. A south-west regional study (Halcrow, 1992) reports that there was an initial rise in crop production in coastal polders but this subsequently stagnated or declined. Experience from previous FCD projects in the north-west region shows that the increases in crop production that appear to be feasible are in reality often difficult to attain (Mott MacDonalds, 1993b). The Bangladesh Agricultural Research Council (BARC, 1989) and Khan (1991) also expressed reservations regarding the performances of FCD projects in increasing rice production.
Similar conclusions were also drawn by Chowdhury et al. (1996). In this study, a regional analysis of Aman production was made. The results are presented in Table 10 and show wide variations in Aman production with respect to incremental increases in FCD coverage. While the NW, SW and SC, and SE and CG regions (Figure 6) show positive relationships between increases in intervention and increases in Aman output, although not necessarily in accordance with the extent of intervention, the NE and NC regions (Figure 6) actually show a decrease in output as a result of increased intervention.
(Source: Chowdhury et al., 1996).
From the above findings, it is difficult to draw any definite conclusions regarding the performances of FCD projects in Aman rice production. While project-based evaluations show definite improvements, regional scale investigations are apprehensive about the overall performance of the FCD projects.
Construction of FCD projects has often been delayed due to underestimation
of the complexity of intervention in a floodplain environment and project
cost. Such delays in construction often reduce the economic viability of
a project and cause unwanted problems during the construction period. It
is observed that small scale projects have been more successful than their
larger counterparts due to the fact that they can be quickly implemented
and have least the impact on floodplain environment.