Rockslides and snow avalanches at Snoqualmie pass have caused frequent closures of I-90, so State and Federal agencies embarked on an improvement project. GEO-Instruments office in Washington is providing automated monitoring for the project, including AMTS, piezometers, instrumented rock dowels, data loggers, and data communications equipment.
These photos show a section of the project where GEO installed 22 instrumented rock dowels on very steep slopes. The instruments are connected to solar-powered loggers that radio data to a base station located at the top of the pass. There, a cellular modem takes the data to the web, where it is processed and displayed graphically on computer screens at Washington DOT.