Project Description

The project focuses on subsidence hazard assessment in several Mexican metropolitans: Mexico City, Morelia, Celaya, and Aguascalientes. We monitor subsidence and its changes with time using InSAR time series, which can detect urban subsidence extremely well. Preliminary studies in Mexico City and Morelia indicate high subsidence rates and severe structural damage to both houses and city infrastructure. The proposed research includes the federal Comison Nacional del Agua (Conagua) authorities as end users that will use the InSAR-derived information and its cartographic products from geodetic imaging to define a better groundwater extraction strategy in areas that undergo extreme subsidence rates, propose better mitigation strategies and ultimately improve water resource management.

Significance
1. InSAR time series observations will provide federal, state and municipal level authorities and water operating agencies valuable information on the spatial and temporal extent of subsidence, and its fault related vulnerability for structural damage in Mexican metropolitan centers.

2. Subsidence information provided to federal, state and local water authorities will be used to minimize hazard and help achieve a sustainable water resource management.

Figure 1: Space-based observed subsidence in 13 cites in central Mexico

Figure 2: PSI results showing subsidence through part of Mexico City. The data were acquired by the Envisat ASAR system between January 2004 and July 2006. Maximum rate (300 mm/yr) occurs in eastern Mexico City and the gradient of subsidence increases towards the remnant of Lake Texcoco (dark rectangle). Master PSI point (white triangle) is located 454.5 meters away from UCHI GPS station, on a remnant volcanic hill.