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Nepal: Baseline Information and it role in Decision making (An illustration from Upper Modi Hydropower Project in Nepal)

There are four decision making points in the sequence of EIA implementation. The nature and the extent of baseline information required at each of the decision points are quite different. The following example of a hydroelectric development project, in relation to likely to impact on fish population will illustrate the four critical decision points and the requirement baseline information, at each stage.

A series of potential sites for generating hydropower has been identified at different stretches of the Modi River in Nepal. The most promising site, where preliminary investigation has suggested a possibility of 30 MW of hydropower generation.

(a) Decision on the Project Approval

Tor tor Ham (Sahar fish) a delicious long-distance migratory fish, is available in plenty in the entire stretch of the Modi River. This species of fish has been reported to migrate upstream for breeding in summer and downstream for feeding in the winter time. Most of the fisherman living on the river side adopt traditional technology to catch the fish and sell their harvest to the local market.

One of the major environmental concern of damming of the river is to impose an obstruction to the upstream and downstream migration of the fish which in turn would like to create a number of issues.

• report from fishermen of the area indicated that the population of fish has declined recently due to the excessive fishing,
  
  
• the obstruction likely to be created by damming would further reduces population and may destroy fish spawning area,
  
  
• the Sahar fish (Tor tor sp) is considered to be most delicious hills stream fish, liked by the local people
  
  
• the fish resources comes under the jurisdiction of Department of Fish and Fishery of the government; the current legislation does not account for the regulation of river fish resources in Nepal. However, in absence of such, regulatory mechanism, it would be highly relevant to consult the local fishermen and the local government about their consensus to proceed with the project, that are likely to produce adverse effect for fish resources of the area.
  
  

For justification of the issues, it is necessary to have sufficient information on the following parameters:

• data on current abundance of fish
  
• fish migratory pattern
  
• spawing characteristic,
  
• localities
  
• the current rate of fish exploitation, and
  
• the economic
  

If information on above parameters are available, the second aspect is to design mitigation measures such as:

• carryout feasibility study in order to establish a fish hatchery to replace the possible loss of fish production,
  
• examine the feasibility for installing a fish ladder in order to facilitate the fish migration, and
  
• explore the possibility of opening-up the potential habitat and spawning ground by removing the obstacle in tributary river.
  

On the basis of availability of above justifications the project should be approved by the authority.

(b) Decision on the Location of Project

If the project is approved for implementation, then the second decision would be to find out an appropriate location for the construction of a dam. Engineering feasibility might have proposed several sites for dam construction, and on the basis of technical and economical consideration, the best site might have been identified. However, from the point of view of the environment, particularly, in the case of fish resources, a more detailed and focused baseline study should have to be conducted at each alternative sites proposed, mainly on:

a) site for damming, which would be likely to have less effect on fish spawning grounds;

b) site which would be likely to create more area for spawning; and

c) site which would be likely to impose minimum obstruction for fish migration.

(c) Decision on the Project Design

At this stage decisions and recommendations should be incorporated into the project design. Primarily the following aspects have to be considered:

• the hydrological regime of the river should be well understood,
  
• a coordinated mechanism in the project design is necessary for maintaining the regular water flow downstream, and
  
• the design has to incorporate all recommended mitigation measures, and also a fish ladder to be included in the design, if necessary.
  

All considerations at the design stage should be backed by baseline information, and whether or not all measures recommended in previous decisions have been taken into consideration in project design.

(d) Decision on the Operation of Project

Consideration at the this stage of project, establishes monitoring and operational feedback system to ensure that the design features built into the project are properly implemented. A number of study should be made at this stage. For example survival rate at of juvenile fish above the dam should be compared with at unaffected parts of the river to see whether newly developed habitat is being used to the extent predicted; and the relationship between fish production in the river, and commercial catch.