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The potentially destructive flooding resulting from rain-on-snow (ROS) events motivates efforts to better incorporate these events and their residual effects into flood-related infrastructure design. This paper examines relationships between measured streamflow surges at streamgages across the Western United States and the meteorological conditions preceding them at SNOTEL stations within the same water catchment. Relevant stream surges are identified using a peak detection algorithm via time series analysis, which are then labeled ROS- or non-ROS-induced based on the preceding meteorological conditions. Both empirical and model-derived differences between ROS- and non-ROS-induced stream surges are then explored, which suggest that ROS-induced stream surges are 3–20 percent larger than non-ROS-induced stream surges. Quantifying the difference between ROS and non-ROS-induced stream surges promises to aid the improvement of flood-related infrastructure design (such as culverts) to better guard against extreme flooding events in locations subject to ROS. [ABSTRACT FROM AUTHOR]

This paper presents an asset management framework for remote monitoring of traffic signal structures for fatigue damage under wind loads, using historical wind measurements from nearby weather stations. Estimate wind profiles developed from the wind data are used to calculate fatigue damage at welded connections for a wide variety of common traffic pole configurations. The analysis is embedded within a novel remote monitoring application that performs the fatigue life analysis in real time for a user defined location and traffic pole configuration. Such a framework is the first of its kind that allows operators to make real time asset management decisions though interactive explorations of the relationship between traffic pole configuration and fatigue life due to local wind conditions. Results are demonstrated using several traffic poles located around Logan, Utah, which has complex topography that creates drastic changes in wind conditions over short geographical distances. The results illustrate the ability of the remote monitoring application to detect small-scale differences in wind conditions that result in significant differences in the estimated fatigue life of traffic structures within communities. Such results highlight the need for, and feasibility of developing site-specific asset management frameworks at a much finer spatial resolution than previous attempts. [ABSTRACT FROM AUTHOR]

Recent amendments to design ground snow load requirements in current US standards have reduced the size of case-study regions by 91% from what they were in previous standards, primarily in western states. This reduction is made possible through the development of highly accurate regional generalized additive models (RGAMs), stitched together with a novel smoothing scheme implemented in the R software package remap, to produce the continental-scale maps of reliability-targeted design ground snow loads available in current standards. This approach allows for better characterizations of the changing relationship between temperature, elevation, and ground snow loads across the conterminous US (CONUS). RGAMs are shown to have 10% or better improvement in mean absolute mapping error in two independently created data sets when compared with traditional mapping techniques. Structures must be able to withstand environmental stresses without collapsing, including snow. Design ground snow loads are estimated using snow measurements taken at weather stations throughout the US. Mapping techniques allow design ground snow loads to be estimated at regions between weather stations. This paper describes a regional approach for mapping design ground snow loads in CONUS and demonstrates the improved accuracy of the approach, relative to previous methods, on two independently created national data sets. [ABSTRACT FROM AUTHOR]