Scope and limitations of Ground Water Prospects Maps


A.Pin pointing bore / tube well points (41/2” & 61/2” dia) may not be accurate.
    --   Scale of mapping (1:50,000 scale)
    --   Accuracy of map: The accuracy of the map is around 100 meters (which includes satellite data accuracy and other mapping errors).
    --   Heterogeneity of the terrain: These maps are generated with limited field checks hence in many cases the hydrogeomorphic units are extrapolated with the help of satellite image features.
    --   Ground survey to estimate the detailed hydrogeological conditions
    --   Ground geophysical survey (electrical resistivity)
    --   Up scaling keeping the map as base to assess the micro level changes

B.Depth variations
    --   Dynamic hydrological conditions
    --   Varying subsurface condition.
    --   Deeper depths to tap the multi layer aquifer system
    --   Drilling of the well near to the fracture system

C.Yield variations
    --   Depletion of water table due to scanty rainfall
    --   Porosity and permeability variations within the unit
    --   Implementation of recharge structure at the time of development of well
    --   Detailed ground geophysical survey

D.Variations in estimated success rate
    --   Non availability of well information.
    --   Inaccessibility of the terrain
    --   Drilling within the network of the fractures.

E.Low yields/poor yields along the fracture areas
    --   Heterogeneity within the fracture aquifers.
    --   Drilling within the intersection of the fractures and confirmed fractures with proper survey.
    --   Null values in Groundwater Quality parameters represents ‘not available or not analyzed’ conditions.
    --   Water Quality observations in the habitation represents Generalized Water Quality scenario. However, actual quality may vary in space and time.

Ground Water Quality Information System (Disclaimer)