Results of hydrologic monitoring on landslide-prone coastal bluffs near Mukilteo, Washington

Open-File Report 2017-1095
Prepared as part of a Technical Assistance Agreement with Sound Transit
By: , and 



A hydrologic monitoring network was installed to investigate landslide hazards affecting the railway corridor along the eastern shore of Puget Sound between Seattle and Everett, near Mukilteo, Washington. During the summer of 2015, the U.S. Geological Survey installed monitoring equipment at four sites equipped with instrumentation to measure rainfall and air temperature every 15 minutes. Two of the four sites are installed on contrasting coastal bluffs, one landslide scarred and one vegetated. At these two sites, in addition to rainfall and air temperature, volumetric water content, pore pressure, soil suction, soil temperature, and barometric pressure were measured every 15 minutes. The instrumentation was designed to supplement landslide-rainfall thresholds developed by the U.S. Geological Survey with a long-term goal of advancing the understanding of the relationship between landslide potential and hydrologic forcing along the coastal bluffs. Additionally, the system was designed to function as a prototype monitoring system to evaluate criteria for site selection, instrument selection, and placement of instruments. The purpose of this report is to describe the monitoring system, present the data collected since installation, and describe significant events represented within the dataset, which is published as a separate data release. The findings provide insight for building and configuring larger, modular monitoring networks.

Suggested Citation

Smith, J.B., Baum, R.L., Mirus, B.B., Michel, A.R., and Stark, B., 2017, Results of hydrologic monitoring on landslide-prone coastal bluffs near Mukilteo, Washington: U.S. Geological Survey Open-File Report 2017–1095, 48 p.,

ISSN: 2331-1258 (online)

Study Area

Table of Contents

  • Preface
  • Acknowledgments
  • Abstract
  • Introduction
  • Previous Work
  • Site Descriptions
  • Field Instrumentation
  • System Reliability and Recommended Improvements
  • Data Preparation for Analysis and Release
  • Overview of Acquired Data
  • Conclusion
  • References Cited
  • Appendix 1. Datalogger Programs
Publication type Report
Publication Subtype USGS Numbered Series
Title Results of hydrologic monitoring on landslide-prone coastal bluffs near Mukilteo, Washington
Series title Open-File Report
Series number 2017-1095
DOI 10.3133/ofr20171095
Year Published 2017
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) Geologic Hazards Science Center
Description Report: vii, 48 p.; Data Release
Country United States
State Washington
City Mukilteo
Online Only (Y/N) Y
Google Analytic Metrics Metrics page
Additional publication details