Highway Performance and Time-Sensitive Industries, 1998

This report addresses delays to freight shippers. Although the focus is on just-in-time (JIT) businesses, the authors also note that non JIT businesses also suffer delays that impact their productivity. The table of contents lists the following headings: chapter 1 - introduction - a trial application: the Des Moines metropolitan area; structure of the report; chapter 2 - reliability at the forefront of freight transport demand - manufacturing and inventory; just-in-time operations in the U.S.; transportation consequences; summary; chapter 3 - JIT operations in Iowa - survey and sample; trucking activity and service; just-in-time truck transportation in Iowa; assessment of factors affecting truck transportation service; summary and conclusions; chapter 4 - travel time uncertainty induced by incidents - a probabilistic model for incident occurrences and durations; calculation of delay; trial application; conclusions; and chapter 5 - conclusions and recommendations - conclusions; recommendations.

Flood-Plain and Channel Aggradation at Selected Bridge Sites in the Iowa and Skunk River Basins, Iowa, HR-350, 1996

Flood-plain and channel-aggradation rates were estimated at selected bridge sites in central and eastern Iowa using four aggradation-measurement methods. Aggradation rates were quantified at 10 bridge sites on the Iowa River upstream of Coralville Lake and at two bridge sites in the central part of Skunk River Basin. Measurement periods used to estimate average aggradation rates ranged in length from 1 to 98 years and varied among methods and sites. A direct comparison cannot be made between aggradation rates calculated using each of the four measurement methods because of differences in time periods and aggradational processes that were measured by each method.