Journal of Water Resources Planning and Management

Existence of several problems associated with the optimization of real‐time operations of reservoir systems is demonstrated. The first problem presented is due to the use of imperfect streamflow (inflow to the reservoir) forecasts. It is shown that there is a significant relationship between the reliability of the forecast information and the operating or forecast horizon to be used in the model. To illustrate the implications of this relationship, an example is given where extending the forecast horizon beyond three days does not improve the performance of the model for real‐time operations. Real‐time operations models often require routing models that relate reservoir releases to the flows at downstream points. It is illustrated with examples that use of approximate reach routing models may cause unexpected problems and may mislead the decision makers. A method to partially resolve the problem is also suggested.

A method for estimating detention storage capacity in stormwater management is presented. A generalized storage‐overflow relationship is derived. This relationship defines real available storage (empty space in detention basin) on the positive range and overflow volumes on the negative range. By using exponential probability density functions for the independent hydrologic variables runoff volumes, runoff durations, and interevent times, and the generalized storage relationship, a new probability distribution is derived for the treatment plant overflow volumes. The new distribution provides an easy‐method for estimating the detention storage and treatment capacity for a design risk level. The methodology has the advantage that it provides easy to use preliminary planning information for stormwater management without the need for extensive simulation.

A method is presented for incorporating subjective information into multi‐objective evaluations. The method is based upon an eigenvalue and eigenvector analysis and structures multi‐objective evaluations into a series of hierarchies in which pairwise comparisons are made. The method is demonstrated in the design of an aquatic monitoring network. Theoretical aspects of the approach are reviewed, including measures of subjective inconsistency, the sensitivity of inconsistency to pairwise comparisons, subjective scaling factors, and sensitivity of final, multi‐objective weights. An interactive computer program for the application of the technique is described.

A comprehensive flood plain management plan was developed for the City of Keene, New Hampshire, reflecting the policies of Section 73 of Public Law 93‐251. Community attitudes were investigated through questionnaires, interviews with community leaders, and interaction with a community advisory committee. A full range of available nonstructural and structural flood damage reduction measures was surveyed. An initial set of measures was selected based on physical, economic, and political feasibility in Keene given the existing stream conditions, available stage‐damage estimates and community attitudes. These initial measures were evaluated in detail, and three alternative flood plain management plans were developed and analyzed using benefit‐cost and environmental assessment procedures. The recommended flood plain management plan for Keene included: (1) A technical assistance program to aid homeowners with flood‐proofing; (2) small dikes to protect selected structures or groups of structures from flooding; (3) channel improvements at constrictions; (4) enhancement of existing storage by restoration and modification of a damaged dam; and (5) development of a flood warning and emergency preparedness system. (6) The experience in Keene represents a prototype study implementing the requirements of Section 73 and can serve as a useful model for future nonstructural flood plain management studies.

The 1982–83 floods on the main stem and tributaries of the Middle and Lower Mississippi River spanned a six‐month period from December, 1982–June, 1983. The flood season was initially marked by three tributary‐centered events followed by a main stem flood on the Lower Mississippi during April, May, and early June. The prolonged period of high water included flash, general, and backwater flooding that prompted requests for U.S. Army Corps of Engineers assistance from states, communities, levee boards, and other local interests. The floods posed a host of difficult challenges for the Lower Mississippi Valley Division and Mississippi River Commission (LMVD/MRC) of the U.S. Army Corps of Engineers. The task of managing the floods was compounded by the scope and complexity of the nation's largest flood control system. In addition to responding to requests for floodfight assistance, the LMVD/MRC was heavily involved in maintaining navigation, monitoring weather and, hydrological data, insuring the integrity of the levee system, as well as operating reservoirs, pumping plants, the Old River Control Structures, and the Bonnet Carre Floodway. The performance of the Mississippi River and Tributaries Project and elements of the is LMVD program justified public investments in a reliable flood control system in the Middle and Lower Mississippi basins.

A spatial approach that disaggregates the water supply system into the components of acquisition‐treatment and transmission‐distribution, allows these components to be studied in isolation and in combination. Each of these components has different cost and physical functions and the cost and performance trade‐offs between these functions can provide important insights into regionalization and cost‐related issues. The Water Supply Simulation Model (WSSM) described in this paper is a system of computer programs that allows for an evaluation of the physical and economic characteristics of a water distribution system in a spatial framework. The development of the model and its application to a case study situation is presented.

Flood plain management requires assessment of the costs and benefits of all projects under consideration. The benefits translate mainly into flood damage reduction. This study presents a methodology for estimating flood damage prior to implementation of flood control structures. In this two‐stage, methodology, a hydroeconomic model for flood damage estimation is first developed, and a flood damage distribution function is then derived from the theory of extreme values in stochastic processes. The distribution function produces an estimation of actualized damages. The Richelieu River basin was selected for a numerical application because of its combined rural and urban characteristics and the fairly extensive sum of knowledge on the basin supplied by previous studies.

Water quality and biological monitoring provide an indication of the degree to which the natural environment has been affected by anthropogenic‐activities. Currently, this monitoring is both expensive and time‐consuming. A new cost‐effective approach to the design of aquatic monitoring networks is presented. Classical analysis of variance (ANOVA) techniques are reviewed and a modified ANOVA model with control station pairs is suggested. An interactive optimization procedure is presented that incorporates a modified gradient search algorithm to select designs which maximize the statistical power of a network for a specified budget or minimize the cost of a network for a specified statistical power requirement. The sensitivity of the model results are explofed as a function of the cost, the number of sampling stations, replicates, and occasions, the Type I and Type II error, estimates of data variance, and cost components for data describing an aquatic species from a New England power facility. It is shown that for specified power and cost, numerous solutions exist providing the designer with a wide selection of alternatives from which to choose.