Steps

Methods

Processes

1

Identification of parameters

Choice of used parameters to calculate the pollution vulnerability index

Thematic mapping

- mapping each parameter at the scale of the studied watershed

- discretization of each parametric map (Cell size = 20 × 20 m)

Reclassification of parameters

Each parameter is subdivided into 3 or 4 classes according to the ratings or weights assigned

2

Weighting of parameters

Prioritize the parameters relative to each other by Saaty method

3

Vulnerability assessment

Combination of the different thematic maps by weighting to obtain a final map of the vulnerability index distribution

4

Determination of protection perimeters or zones

Delimitation of protection perimeters or zones (Zone 1, Zone 2 and Zone 3) according to the vulnerability map