| An Evaluation of Water Quality at Fort Monmouth, New Jersey, Using the EPANET Model |
SEP 95 |
62 pages |
| Authors:
Thomas M. Walski; Stephen J. Draus; WILKES COLL WILKES-BARRE PA
|
 | Under the Facilities Engineering Applications Program, the U.S. Army Corps of Engineers wanted to test the capability of the EPANET computer model for evaluating water quality in water distribution systems. Fort Monmouth, New Jersey, has experienced low chlorine residuals levels. The EPANET model was calibrated using hydrant flow tests to predict chlorine die-off in the distribution system at the Fort. The model was then used to compare the effects of ... |
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| New York Water Supply Infrastructure Study. Volume 5. Analysis of Replacement Policy |
JAN 90 |
114 pages |
| Authors:
James W. Male; Thomas M. Walski; Adam H. Slutsky; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS ENVIRONMENTAL LAB
|
| This report analyzes possible policies for replacing segments of New York City's water distribution system. Strategies were developed and tested, and compared with the Bureau of Water Supply's current strategy of replacing a main segment (equal to about 1/12 of a mile, on average) if it has had two or more breaks. A mathematical model was developed to conduct the analysis, which incorporates the cost of replacing water mains of ... |
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| Reliability of the Federally Owned Water Main System |
NOV 88 |
173 pages |
| Authors:
Donald V. Chase; Lindell E. Ormsbee; Thomas M. Walski; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS ENVIRONMENTAL LAB
|
| This report assesses the reliability of the existing Federally Owned Water Main (FOWM) system with a special emphasis on possible long-term outages. A mathematical model of the system was created using information supplied by Washington Aqueduct Division and Arlington County officials. The model was calibrated using fire hydrant flow test results. The response of the system to different pipe outages under different loading conditions was then examined using the computer ... |
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| New York Water Supply Infrastructure Study. Volume 4. Staten Island |
APR 88 |
|
| Authors:
Thomas M. Walski; Roy Wade; Wayne W. Sharp; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS ENVIRONMENTAL LAB
|
 | This report describes an evaluation of water main breaks in the Staten Island, New York, water distribution system. The report describes a statistical evaluation of historical pipe breaks and identifies patterns and trends in the data, including such things as the increase in circumferential pipe breaks during winter months and an increase in longitudinal breaks (probably due to surges) during summer months. The actual break rates (in breaks per year ... |
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| Dredging Operations Technical Support Program. Planning-Level Cost Estimates of Dredged Material Containment Islands in New York Harbor |
APR 88 |
|
| Authors:
Thomas M. Walski; Thomas E. Schaefer Jr; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS ENVIRONMENTAL LAB
|
| Planning-level cost estimates are presented for each of three containment island configurations to be located in Lower New York Bay. Estimates are considered to be only 'order of magnitude' values based on typical unit prices for construction and operation of the assumed island configurations. Islands are limited to 500 acres including all dike boundaries. Sand dike, rock and sand dike, and sheet pile cofferdam designs are considered; cost estimates developed ... |
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| Predicting Internal Roughness in Water Mains |
FEB 1988 |
27 pages |
| Authors:
Thomas M. Walski; Wayne W. Sharp; F. D. Shields Jr; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS ENVIRONMENTAL LAB
|
| A method is presented for predicting the Hazen-Williams C-factor for unlined metal water mains as a function of pipe age. The method has two steps: (a) finding the growth/rate of internal roughness, alpha, for the water main using either historical C-factor data or water quality data; and (b) using predictive equations for an estimate of a future C-factor. The predictive equations presented in this report were derived using linear regression ... |
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| Techniques for Improving Energy Efficiency at Water Supply Pumping Stations |
NOV 87 |
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| Authors:
Lindell E. Ormsbee; Thomas M. Walski; Donald V. Chase; Wayne W. Sharp; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS ENVIRONMENTAL LAB
|
| This report presents an application of a methodology for reducing the amount of energy used for pumping in treated water distribution systems. The methodology can be divided into three steps: (a) field testing of pumps to ensure that they are performing to specifications, (b) determining the best combination of pumps to achieve a given discharge, and (c) determining the optimal discharge (or tank water levels). The methods presented in the ... |
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| Water Distribution Analysis and Optimization (WADISO). User's Guide and Documentation. Chapter 28, Parts 1 and 2, Change 6 |
01 JUL 87 |
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| Authors:
Johannes Gessler; John W. Sjostrom; Thomas M. Walski; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS ENVIRONMENTAL LAB
|
| This document provides guidance on the use of a computer program WADISO (Water Distribution System Analysis and Optimization). The computer model consists of three major parts: steady state computer simulation, optimization, and extended period simulation. The steady state simulation portion computes flows and pressures in pipe networks under steady state conditions. The optimization portion optimally sizes pipes in a water distribution system and selects optimal pipes for cleaning and lining. ... |
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| New York Water Supply Infrastructure Study. Volume 3. The Bronx and Queens |
JUL 87 |
|
| Authors:
Thomas M. Walski; Roy Wade; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS ENVIRONMENTAL LAB
|
| This report describes an evaluation of the water distribution system in the Bronx and Queens, with special emphasis on water main breaks. The report presents a statistical analysis of breaks by sizes, causes, and season, among other considerations. It also examines trends in break rate with age of pipe and determines that the pipes are deteriorating with time, although these effects are masked somewhat by different laying practices and pipe ... |
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| Water Distribution System Optimization |
OCT 85 |
|
| Authors:
Johannes Gessler; Thomas M. Walski; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS ENVIRONMENTAL LAB
|
| This report describes the development of a computer program WADISO (Water Distribution Systems Optimization) which can be used to optimally size pipes in water distribution systems and select optimal pipes for cleaning and lining. The program can also be used as a steady-state simulation program to calculate flows and pressures in pipe networks. The simulation portion of the program uses the node method with sparse matrix techniques to reduce computations. ... |
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| Proceedings of Symposium on Cost Estimating for Water Supply Planning Studies Held at Tampa, Florida on 14-16 March 1983 |
SEP 1983 |
|
| Authors:
Thomas M. Walski; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS ENVIRONMENTAL LAB
|
| This report contains the papers presented at the symposium 'Cost Estimating for Water Supply Planning Studies' as conducted at the ASCE Specialty Conference, Water Supply--The Management Challenge, in Tampa, Florida, 14-16 March 1983. The proceedings include an overview chapter, description of alternative approaches from the detailed 'systems estimate' to the more general approach of 'parametric estimating'. Other topics include verification of estimating models, spatial cost estimating, estimating for small systems ... |
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| Planning Level Cost Estimating-Science, Art or Witchcraft? |
SEP 1983 |
|
| Authors:
Thomas M. Walski; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS
|
| Development of a planning level cost estimate is a different process than development of estimates based on detailed plans and specifications. Because it is part of an iterative process, planning level estimating requires an approach that yields estimates quickly and reproducibly while accounting for the effects of the most important design parameters. There are tradeoffs between accuracy and level of effort involved in preparing these estimates. As the input data ... |
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| Verification of Maps Cost Estimating Procedures, |
SEP 1983 |
|
| Authors:
Thomas M. Walski; Anita K. Lindsey; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS
|
| The purpose of this study was to verify the Methodology Areawide Planning Studios cost estimating procedure against an independently determined set of cost data. From this kind of analysis it is possible to: determine the accuracy of the individual modules, identify and correct minor shortcomings of the program, and identify potential major program modifications and additions. This paper has been prepared to present the results of the verification study, thereby ... |
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| Recreation Research Program: Computing Cost-Effectiveness of Alternative Sanitary Facilities |
MAR 1983 |
|
| Authors:
Michael R. Waring; Ronald W. Hodgson; Thomas M. Walski; Anita K. Lindsey; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS
|
| Sanitary facilities at Corps of Engineers recreation areas contribute significantly to the total cost for both construction and operations and maintenance. In many cases, these costs appear to be unrealistic and the resultant facilities not cost-effective. This is especially true when the facilities are either overdesigned or underdesigned for the level of development or visitation of the area. This lack of cost-effectiveness can be partially attributed to the lack of ... |
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| Water Supply Analysis for the Guam Comprehensive Study |
OCT 1982 |
|
| Authors:
Thomas M. Walski; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS ENVIRONMENTAL LAB
|
| This report presents an analysis of five types of water supply alternative plans for public water use on Guam. These include (1) northern lens aquifer plus military sources; (2) northern lens aquifer only; (3) northern lens aquifer plus southeastern river; (4) southeastern river development only, and (5) southeastern river development plus military sources. There are two parts to the report. The first part, Water Distribution System Analysis, presents the results ... |
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| Verification of Cost Estimating Procedures for MAPS Computer Program |
MAY 1982 |
|
| Authors:
Anita K. Lindsey; Thomas M. Walski; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS ENVIRONMENTAL LAB
|
| The MAPS (Methodology for Areawide Planning Studies) computer program is often used to develop planning level cost estimates for a large array of water resources facilities including dams, pipes, pumping stations, open channels, storage tanks, tunnels, water treatment plants, and wellfields. While the MAPS cost estimates have often been checked against actual facility costs, this study was conducted to systematically verify the MAPS cost functions against a set of actual ... |
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| Water Main Repair/Replacement for Binghamton, New York. |
JAN 1981 |
|
| Authors:
Thomas M. Walski; Anthony Pelliccia; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS ENVIRONMENTAL LAB
|
| The cost of water main breaks can represent a significant portion of a water distribution system's maintenance costs. While there exists a good deal of qualitative guidance on why pipes break, and when they should be replaced, there are no universal, quantitative rules for determining when to replace pipe. In this study, a model was developed to predict pipe breaks for the Binghamton, N.Y., water distribution system as a function ... |
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| Application of Maps to the Salinas-Monterey Urban Study. Appendices B, F and G. |
AUG 1979 |
|
| Authors:
Thomas M. Walski; Anthony C. Gibson; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS ENVIRONMENTAL LAB
|
| This appendix presents the data contained in the MAPS headwater data base. It consists of the title for the headwater, the size of the drainage area above the reservoir site or diversion, and the flow at the reservoir site or diversion for each month of the design dry cycle. The flows are given in units of cubic feet per second (cfs) and million gallons per day (mgd). A value for ... |
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| Application of Maps to the Salinas-Monterey Urban Study. |
AUG 1979 |
|
| Authors:
Thomas M. Walski; Anthony C. Gibson; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS ENVIRONMENTAL LAB
|
| The MAPS (Methodology for Areawide Planning Studies) computer program, developed at the U. S. Army Engineer Waterways Experiment Station (WES), was used to evaluate the engineering aspects of alternative water supply plans for the Salinas-Monterey Urban Study conducted by the U. S. Army Engineer District, San Francisco. Using MAPS, the WES study team identified feasible water supply plans, developed staging for required facilities, and calculated capital and operation and maintenance ... |
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| Properties of Steady, Viscosity-Stratified Flow to a Line Sink. |
JUL 1979 |
|
| Authors:
Thomas M. Walski; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS
|
| Viscosity stratification (variation of the viscosity of a fluid with depth) can significantly modify the velocity profiles observed in a fluid being selectively withdrawn from a tank or duct. A mathematical model is developed to predict velocity distribution for steady, Newtonian, slow, laminar, two-dimensional, viscosity-stratified flow to a line sink. The mathematical model was verified in experiments conducted in three flumes using sugar and carboxymethylcellulose to create density and viscosity ... |
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| Weir Design to Maintain Effluent Quality from Dredged Material Containment Areas. |
MAY 1978 |
|
| Authors:
Thomas M. Walski; Paul R. Schroeder; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MISS
|
| The suspended solids concentration in the effluent water from an upland containment area being filled with fine-grained dredged material can be significantly influenced by the length of the weir and the depth of the ponded water. This study develops a procedure for designing and operating the weir to maintain good effluent quality, given a flow and dredged material type. Stratified-flow and sediment-transport models were investigated to describe the depth of ... |
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