• The Impact of Snowfall on Airport Operations and Delays

      Lee, Jukwan; Yan, Jia (2019-03-31)
      Flight delays or cancelations due to snowfall are a costly inconvenience, not only to airports but also to airlines, passengers and society as a whole. However, no quantitative research has ever been done to provide an analytical explanation about the issue. Though being a reliable alternative to melt snow on the runway and mitigate flight delays, the Heated Pavement System is not adopted in any US airports because of concerns over the initial investments and maintenance costs being higher than the economic loss from delays during unpredictable snowfall days. Combining weather and domestic flight data in Boston and Los Angeles regions, we analyze the benefits and costs associated with installing the Heated Pavement System. Using two advanced econometric methods, the Difference in Difference in Difference (DDD) and the nearest neighbor matching, we first develop a Delay Analysis model to evaluate the exact effect of snowfall on flight delays, and then we calculate the delay costs. Based on the empirical findings, we conduct cost-benefit analysis of installing HPS at the three airports in Boston area. Our results indicate that HPS is feasible for airports with a great number of flights and passengers, such as Boston Logan airport.
    • SIZING HYDRAULIC STRUCTURES IN COLD REGIONS TO BALANCE FISH PASSAGE, STREAM FUNCTION, AND OPERATION AND MAINTENANCE COST

      Blank, Matt; Dockery, David; Pohl, Christina (2019-03)
      The purpose of this research was to evaluate how characteristics of hydraulic structures, such as slope or size, used at crossings over waterways relate to operation and maintenance (O&M) effort, fish passage, and stream function. Data on O&M concerns, fish passage concerns, and crossing characteristics were collected from 45 road-stream crossings in Prudhoe Bay, Alaska, during lower and higher water periods in both 2014 and 2015 (four events total). Logistic regression and generalized mixed models were used to examine relationships between O&M effort (response) and five explanatory variables. For all data from all years combined, there were no observable associations among O&M and culvert type or constriction ratio. However, lower constriction ratios were observed for sites with O&M needs in the June 2014 data set. The proportion of sites with both fish passage and O&M concerns was 0.52; comparatively, the proportion of sites with no fish passage concern but with O&M concern was 0.35.