A system network and methods supported by a constellation of GNSS satellites orbiting around the Earth, and deployed for precise remote monitoring of the spatial displacement, distortion and/or deformation of stationary and/or mobile systems, including buildings, bridges, and roadways. The methods involve (i) embodying multiple GNSS rovers within the boundary of the stationary and/or mobile system being monitored by the GNSS system network, (ii) receiving GNSS signals transmitted from GNSS satellites orbiting the Earth, and (iii) determining the geo-location and time-stamp of each GNSS rover while the stationary and/or mobile system is being monitored for spatial displacement, distortion and/or deformation, using GNSS-based rover data processing methods practiced aboard the system, or remotely within the application and database servers of the data center of the GNSS system network. The GNSS rovers also include on-board instrumentation for sensing and measuring the depth of water ponding about the GNSS rovers.