The DRASTIC-Sg model: an extension to the DRASTIC approach for mapping groundwater vulnerability in aquifers subject to differential land subsidence, with application to Mexico City
Por:
Hernández-Espriú A., Reyna-Gutiérrez J.A., Sánchez-León E., Cabral-Cano E., Carrera-Hernández J., Martínez-Santos P., Macías-Medrano S., Falorni G., Colombo D.
Publicada:
1 sep 2014
Resumen:
Mexico City relies on groundwater for most of its domestic supply. Over
the years, intensive pumping has led to significant drawdowns and,
subsequently, to severe land subsidence. Tensile cracks have also
developed or reactivated as a result. All such processes cause damage to
urban infrastructure, increasing the risk of spills and favoring
contaminant propagation into the aquifer. The effects of ground
deformation are frequently ignored in groundwater vulnerability studies,
but can be relevant in subsiding cities. This report presents an
extension to the DRASTIC methodology, named DRASTIC-Sg, which focuses on
evaluating groundwater vulnerability in urban aquifers affected by
differential subsidence. A subsidence parameter is developed to
represent the ground deformation gradient (Sg), and then used to depict
areas where damage risk to urban infrastructure is higher due to
fracture propagation. Space-geodetic SqueeSAR data and global
positioning system (GPS) validation were used to evaluate subsidence
rates and gradients, integrating hydrogeological and geomechanical
variables into a GIS environment. Results show that classic DRASTIC
approaches may underestimate groundwater vulnerability in settings such
as the one at hand. Hence, it is concluded that the Sg parameter is a
welcome contribution to develop reliable vulnerability assessments in
subsiding basins.
Filiaciones:
Hernández-Espriú A.:
Univ Nacl Autonoma Mexico, Fac Engn, Div Earth Sci, Hydrogeol Grp, Mexico City 04360, DF, Mexico
Reyna-Gutiérrez J.A.:
Univ Nacl Autonoma Mexico, Fac Engn, Div Earth Sci, Hydrogeol Grp, Mexico City 04360, DF, Mexico
Sánchez-León E.:
Univ Nacl Autonoma Mexico, Fac Engn, Div Earth Sci, Hydrogeol Grp, Mexico City 04360, DF, Mexico
Cabral-Cano E.:
Univ Nacl Autonoma Mexico, Dept Geomagnetism & Explorat, Inst Geophys, Mexico City 04360, DF, Mexico
Carrera-Hernández J.:
Univ Nacl Autonoma Mexico, Ctr Geociencias, Juriquilla, Queretaro, Mexico
Martínez-Santos P.:
Department of Geodynamics, Universidad Complutense de Madrid, Madrid, Spain
Macías-Medrano S.:
Univ Nacl Autonoma Mexico, Fac Engn, Div Earth Sci, Hydrogeol Grp, Mexico City 04360, DF, Mexico
Falorni G.:
TRE Canada Inc., Vancouver, BC, Canada
Colombo D.:
Tele-Rilevamento Europa T.R.E. s.r.l., Milan, Italy
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