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Gary D. Tasker

Publications and source records attributed to Gary D. Tasker.

49 records · Page 3Linked to original sources
USGS1982

Estimating peak flow characteristics at ungaged sites by ridge regression

A regression simulation model, is combined with a multisite streamflow generator to simulate a regional regression of 50-year peak discharge against a set of basin characteristics. Monte Carlo experiments are used to compare the unbiased ordinary lease squares parameter estimator with Hoerl and Kennard's (1970a) ridge estimator in which the biasing parameter is that proposed by Hoerl, Kennard, and Baldwin (1975). The simulation results indicate a substantial improvement in parameter estimation using ridge regression when the correlation between basin characteristics is more than about 0.90. In addition, results indicate a strong potential for improving the mean square error of prediction of a peak-flow characteristic versus basin characteristics regression model when the basin characteristics are approximately colinear. The simulation covers a range of regression parameters, streamflow statistics, and basin characteristics commonly found in regional regression studies.

Open-File Report↗
USGS1982

Design of surface-water data networks for regional information

This report describes a technique, Network Analysis of Regional Information (NARI), and the existing computer procedures that have been developed for the specification of the regional information-cost relation for several statistical parameters of streamflow. The measure of information used is the true standard error of estimate of a regional logarithmic regression. The cost is a function of the number of stations at which hydrologic data are collected and the number of years for which the data are collected. The technique can be used to obtain either (1) a minimum cost network that will attain a prespecified accuracy and reliability or (2) a network that maximizes information given a set of budgetary and time constraints.

Water Supply Paper↗
USGS1977

Hydrologic data of the coastal drainage basins of southeastern Massachusetts, Plymouth to Weweantic River, Wareham

The principal basins in this study in southeastern Massachusetts are those of Town Brook, Eel River, and Beaverdam Brook, all draining to Cape Cod Bay; Herring Brook draining to the Cape Cod Canal; and Red Brook, Agawam River, Wankinco River, and Weweantic River, all draining to Buzzards Bay. This report presents, in tabular form, selected records of wells, test wells , borings, and important springs; measurements of stream discharge, specific conductance, and temperature at partial-record stations; chemical analyses of ground water and surface water; and a summary of municipal water sources and additional sources available. The data were collected from 1969 to 1971 in cooperation with the Massachusetts Water Resources Commission. (Woodard-USGS)

Open-File Report↗
USGS1975

Hydrologic data of the coastal drainage basins of southeastern Massachusetts, Weir River, Hingham, to Jonas River, Kingston

The principal basins are those of Weir River, James Brook, Bound Brook, North River, South River, and Jones River, all draining to Massachusetts Bay and Cape Cod Bay. These basins are bounded on the north by the Weymouth River basins, on the west by the Taunton River basin, and on the south by small basins that drain to Cape Cod Bay. The basins included all, or parts of, the Norwell, Pembroke, Plymouth, Plympton, Rockland, Scituate, Weymouth, and Whitman. With the following exceptions, each town is served by its own municipal water system--Hingham and northwest Cohasset by the Hingham Water Company; Abington and Rockland by the Abington-Rockland Joint Water Works; and Plympton lacks a public water supply. Weymouth and Cohasset are in Norfolk County; the other towns are in Plymouth County. This report presents, in tabular form, selected records of wells, test wells, borings, and springs; measurements of stream discharge, specific conductance, and temperature at partial-record stations; chemical analyses of ground water and surface water; and a summary of municipal water sources and additional sources available. The data were collected during a study of the drainage basins from 1969 to 1971 in cooperation with the Massachusetts Water Resources Commission. The report is released in order to make available to the public and to local, state, and federal agencies basic hydrologic information that may aid in planning water-resources development. Basic records contained in this report and streamflow data published elsewhere (U.S. Geol. Survey, 1960 et seq.) complement an interpretive report (Williams and Tasker, 1974).

Massachusetts↗
USGS1975

Combining estimates of low-flow characteristics of streams in Massachusetts and Rhode Island

The number of base-flow measurements needed to meet specified accuracy goals for estimating low-flow characteristics at ungaged sites can be reduced by combining an estimate based on a regression of base-flow measurements on discharges from a nearby continuous long-term gaging station with an estimate based on a regional relationship developed from regressing the low-flow characteristics on basin characteristics. The estimates should be combined by weighting each inversely with its variance from the true value. Empirically estimated values of variance of the estimated 7- day, 10-year low flow from its true value indicate that more than six or eight base-flow measurements add" little to the confidence with which such an estimate is made.

Massachusetts, Rhode Island↗
USGS1974

Progress report on flood magnitude and frequency of Vermont streams

A technique is presented for estimating the magnitude and frequency of floods on streams in Vermont with drainage areas between 0.27 and 1,040 square miles. Multiple-regression techniques are used to define the relation between flood peaks, collected at a network of gaging stations maintained by the U.S. Geological Survey, and a set of basin characteristics. Results show that flood peaks may be estimated from knowledge of the basin's drainage area, average seasonal snowfall, area of lakes and ponds, and maximum 24-hour rainfall having a recurrence interval of 2 years. The relations are presented graphically for user convenience.

Vermont↗
USGS1973

Method for estimating the diversion potential of streams in eastern Massachusetts and southern Rhode Island

A simple method is proposed for estimating the probable magnitude and frequency of streamflow that is in excess of predetermined minimum streamflows required downstream in eastern Massachusetts and southern Rhode Island. Regional curves relate these annual volumes of streamflow excess to the average annual discharge and the median 7-day annual minimum flow of the site. Use of the curves is illustrated by a hypothetical example.

Massachusetts, Rhode Island↗