The purpose of this report is to describe low-flow characteristics of streams in the Pecatonica-Sugar River basin, Wisconsin, where streamflow data have been collected, and to present equations for estimating low-flow characteristics at ungaged sites. Low-flow characteristics were estimated for 11 gaging stations, 25 low-flow partial-record stations, and 207 miscellaneous sites in the basin. Estimates of flow duration were made at the 11 gaging stations. Also, low-flow discharge measurements are listed for 16 miscellaneous sites where insufficient data were available to estimate low-flow characteristics, Four equations are provided to estimate low-flow characteristics at ungaged sites and at sites where one base-flow discharge measurement is available. The equations were determined from multiple-regression analyses that related low-flow characteristics at gaging stations and partial-record stations to basin characteristics. Drainage area and base-flow index were the most significant parameters for these analyses. The standard error of estimate of the 7-day, 10-year low flow was provided. The average SE-j f iQ in the basin ranged from 10 to 64 percent and was dependent on the amount of low-flow data available. This study was in cooperation with the Wisconsin Department of Natural Resources. This report is part of a series of twelve planned reports to describe low-flow characteristics of the major basins in Wisconsin (fig. 1). The report includes: estimates of the magnitude and frequency of recurrence of low flow for sites where systematic streamflow information has been collected, discharge values from low-flow discharge measurements at numerous sites throughout the basin, and a method to estimate low-flow characteristics at ungaged sites and at sites where one base-flow measurement has been made. WISCONSIN LAKE SUPERIOR BASIN

A network of 93 gaging stations that provide surface-water stage, flow (discharge), and tide-level data on a "realtime" basis through satellite, radio, and telephone telemetry is operating (May 2003) in New Jersey through a cooperative effort of the U.S. Geological Survey (USGS) and other agencies. The stream data from these stations are transmitted every 1 to 4 hours and then are immediately posted for viewing on the Internet. This fact sheet describes the "real-time" monitoring network, and the equipment used to measure stage and flow and to transmit the data for viewing on the Internet. Instructions for viewing the data are included. The agencies cooperating in the operation and maintenance of the "realtime" surface-water data network are Background This statewide network consists of several sub-networks that were created to provide time-critical surfacewater data as well as information on long-term hydrologic conditions and trends in stream stage, flow (discharge), and tide levels within the State of New Jersey and to make the data available quickly. The gaging stations in these "real-time" networks, located throughout New Jersey (fig. 1), provide time-critical information for the monitoring of floods, droughts, and daily streamflow conditions needed for public safety; water-supply management; and the daily operations of water supply and receiving-water discharges. This combined statewide network, for example, provides data that allow for timely flood warnings to the public and evacuations in flood-prone areas. The system provides upto-date observations of drought conditions for the optimum management of water supplies and up-to-date information on streamflow conditions for fishermen, canoeists, kayakers, boaters, and other recreational users. In addition, the data from this network can be used to estimate the most recent stream and tide conditions at nearby stations that do not have satellite telemetry. Surface-water stage and streamflow information typically is used by engineers, planners, water-supply managers, emergency-management personnel, and the general public for a variety of purposes. Some of the uses for this streamflow information include incorporation into the design of bridges, dams, flood detention and control struc-U.

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Six methods of estimating peak discharges of urban streams were compared and evaluated for applicability to urban streams in New York. Discharge and frequency values developed from a series of synthesized annual flood records were compared with values obtained from the six methods. The synthesized flood records were computed from rainfall-runoff models of 11 urban basins in three counties across the State. Four of these basins had a sufficient period of record to enable rainfall-runoff modeling of two different 5-year periods so that increases in peak flow due to increased urbanization could also be used for comparison of the six methods. A graph analysis and three statistical analyses were made to evaluate the closeness of fit and bias of the methods. All methods showed a tendency to overestimate synthetic urban flood-magnitude values, but the two that adjust rural flood-frequency estimates on a nationwide basis showed smaller standard errors of estimate and bias. The standard errors for these two methods ranged from 44 to 57 percent over the six recurrence intervals (2, 5, 10, 25, 50, and 100 year), and the bias ranged from +28 to +53 percent. The bias, however, is probably due to errors inherent in using synthetic records and in applying the New York rural flood-frequency equations to urban basins with small drainage areas. In 1981, the U.S. Geological Survey, in cooperation with New York State Department of Transportation, began a 3-year study to evaluate several published methods of estimating flood discharges of ungaged urban streams in New York State. Long-term peak-discharge records synthesized from previously developed rainfall-runoff models were used to test each method's applicability. These models were calibrated and verified with data from gaged streams in urbanized basins. Purpose and Scope This report evaluates six published methods of estimating peak discharges of ungaged streams in urban areas and identifies those that most closely match the synthesized flood peaks. Results are plotted on a series of graphs and summarized in several tables that give the standard errors, bias, and percent differences between estimated and synthetic peak-discharge increases due to urbanization for each of the methods evaluated. APPROACH Urban development within most gaged urban watersheds in New York has been increasing during the streams' period of record. This constant increase has resulted in a set of nonhomogenous annual peaks that are unsuitable for log-Pearson flood-frequency analyses. Therefore, a rainfall-runoff model was developed for each basin for short periods (5 years or less) during which the impervious area increased less than 5 percent. These models, combined with long-term rainfall data (33 to 59 years of record) from nearby precipitation stations (fig. 1) were used to generate long-term synthetic streamflow records. The peak discharges computed from these synthetic records were then compared to those obtained through the six estimating methods, and analyses were then made to evaluate the methods.