Robert J. Houghtalen

optimizing Temporal Water Allocation by Irrigation Ditch Companies

ABSTRACT Adynamic programming (DP) algorithm is presented for allocation of irrigation water over time by ditch companies. The algorithm optimizes weekly deliveries of water to farmers and uses a single state variable, total storage in reservoirs at the beginning of each week. The DP objective is minimization of the sum of squared shortages over the irrigation season. The DP solution consists of optimal operating rules in the form of tables which indicate optimal target end-of-week storage as a function of beginning-of-week storage. One table is obtained for each week of the season. Stochastic treatment of crop water demand is compared against deterministic treatment using a case study ditch company near Fort Collins, CO. In repetitive simulations, stochastic DP always outperformed deterministic DP in terms of average sum of squared shortages, even when only two years of historical weather data were available for characterizing the reference E^ process.

Simple Rating System for Identification of Failure-Critical Culverts and Small Structures

Although bridges are a highly visible and crucial part of the highway infrastructure, smaller structures typically classified as culverts exist in even greater numbers. Nearly invisible to the public, culverts are crucial components of highways. Failure of culverts can lead to flooding, roadway damage, interruption of traffic, and even fatal accidents. Several states have implemented successful culvert inspection programs, but others are only beginning to formalize their culvert inspection and maintenance. Even after periodic inspection programs are in place, planners need a tool for consistent guidance to identify structures most in need of attention. This paper reports on a simple rating system based on a new culvert inspection program recently implemented by the Indiana Department of Transportation. The rating system uses weighting factors that can be adjusted by the user to provide an overall rating of a culvert based on ratings of specific characteristics of a culvert. The tool can be used to provide...