To document the methodology for Aquifer Mapping - especially when undertaken in an urban context and with citizen participation.
The main document is generic in nature and does not refer to any specific maps or organisations with respect to the Bangalore Aquifer Mapping project. Specific information with respect to the project is maintained in the Appendix.
The methodology involves three tracks - Hydrogeological, Social and Platform. For each of the tracks there are expected outputs and the methodology to be followed to achieve the expected outputs. The points and junctures where these three tracks need to work together is also highlighted.
The issues with undertaking an aquifer mapping project of this nature (urban and participatory) and the innovations that might be required are also listed.
Methodology for the Hydrogeological Track
The primary aim of this track is to generate a better scientific understanding of the groundwater resource at an aquifer level. An attempt to create an aquifer map will be made based on integrating and overlaying data and information mentioned above. The study area being an urban setting is thus unlikely to have good geological exposures. Thus hydrogeological data from borewells collected through narratives forms an important process in generating data.
Data will also be gathered from construction sites and quarries where geology beneath is exposed easily. The narrative of borewells will also record zones/levels at which water was struck while drilling.
A combination of geological information derived from available maps, narratives, zones where water was struck while drilling, depth of borewells, periodic water level fluctuation, average static water level and to some extend water quality will help generate an aquifer map.
Initially geological information will be fed in an excel sheet to generate certain 2 dimensional hydrogeological sections such as shown below:
Drawing upon inferences from these certain maps/layers depicting primary aquifer information will be created using softwares like Surfer which inturn could be overlayed onto the platform. The same hydrogeological information along with information related to water quality would be used to create outputs in 3-Dimensions such as follows to get a better understanding for visualisation:
A combination of different types of dataset from that being collected will be overlaid in order to draw inferences regarding aquifer level information.
Overlay of water quality information from borewells on google maps
Co-relating hydrogeological data over demand data would be a crucial aspect in the project. The supply for a demand may not necessarily be sourced from the same area where demand is generated. The aquifer boundaries too may or may not be in line with the demand area.
Expected output of the Social track
Methodology for the Social Track
Expected output of the Platform Track
Methodology for the Platform Track
Note on software
Open Source Software (OSS) has been used for this project. This is because OSS consists of proven technology that is flexible, inexpensive and does not require lock-in to a vendor’s proprietary software. Further, OSS software can be customized for the project’s requirements. There are continual enhancements made by the OSS community which ensures that the technology is kept up-to-date. OSS is also better in terms of adhering to open standards compared to proprietary software, making inter-operability easier.