FUZZY - AUGMENTED GEOSPATIAL STORMWATER SUITABILITY MODELING FOR CHENNAI CITY OF INDIAStalin Subbiah, Parthiban P., Mahesh R. and Das A.
Over the years, with spatio-temporal fluctuation in monsoonal precipitation, supported by rapid changes in landuse pattern, has created severe water-stress, especially in major urban cities of India, including Chennai. Under such changing scenario, proper delineation of stormwater regimes play a very vital role in designing an effective water management plan. With this view the present research work has been carried, with regard to Chennai city of India, by utilizing the thematic geospatial database, with integrated Fuzzybased expert system, so as to demarcate the litho-climatic zones suitable for surface harvesting of stormwater. The geospatial analysis carried out in this work involves base map-preparation, with soil, precipitation, landcover, drainage, slope and road-layers. The specific set of attributes catering to different regions of the study area were evaluated with regard to stormwater suitability index, obtained by fuzzy inference system (FIS) using MATLAB, employing triangular membership functions, domain/expert based rule-set and weightages based on UC Davis Extension Fuzzy approach. The study reveals distinct delineation of storm water suitability zonation, ranging from very high (33.09 %) to high (25.70 %) to medium (24.46 %) to low (11.53 %) to exceptionally low (5.20%). The present geospatial approach, fuzzy-expert-system and specific weightages are easily replicable for other regions, as well, with suitable calibration.