|Statement||prepared for Wyoming Water Development Commission by Hugh Lowham ... [et al.].|
|Contributions||Wyoming Water Development Commission, Lowham Engineering LLC|
|LC Classifications||GB1225.W8 E88 2009|
|The Physical Object|
|Pagination||iv, 26 leaves :|
|Number of Pages||26|
|LC Control Number||2010368119|
Streamgages do not measure streamflow directly. Rather, streamflow monitoring involves several steps, which generally include (1) continuously measuring and recording the stage of a stream, (2) periodically taking discharge measurements in the stream, (3) developing the relation between stage and discharge for the site and applying this relation to the continuous . Streamflow measurements are commonly based on water level measurements that are converted to a discharge rate using a rating curve (see Fig. ).The rating curve is constructed based on a sample of streamflows measured using the (time-consuming) velocity–area method and their corresponding water level (concurrent streamflow and water level data sample is . Discharge measurements must be made for at least three different water surface elevations: low flow, median flow, and high flow. 2. The section that is measured should be accessible at all water surface elevations and discharges to be measured. Choose a straight reach of stream where flows are relatively by: Monthly streamflow records from gaging stations with more than 5 years of record were extended to a year base period, , using a mixed- station, record-extension model. Monthly streamflow characteristics were computed from the extended record. Four statistical methods--basin characteristics, active-channel width, concurrent measurement, and weighted average were used to estimate.
The estimated bias limits from these data sets should have accounted for most, if not all, unknown and unknowable bias errors encountered in these measurements. The results from this study may be used to determine a nominal bias limit for moving-boat ADCP discharge measurements. Methods for Estimating Monthly Streamflow Characteristics at Ungaged Sites in Western Montana For sale by the Books and Open-File Reports Section, U.S. Geological Survey, Federal Center, Box , Denver, CO Concurrent-Measurement Method 8 Weighted-Average Estimate Slope, and Discharge 5 3. The Use of Surface Slope in Determining Flow 7 4. Correcting for Unsteady Effects in Obtaining Discharge from Stage 13 5. Hydraulic Derivation of Rating Curves 21 6. Representation, Approximation and Calculation of Rating Curves 25 7. Conclusions and Implications for Management 39 8. References 41 Appendix A. discharge permits to dischargers to streams and for limiting withdrawals of water from streams. This report presents techniques for estimating the 7Q10 for ungaged sites on streams in Mississippi based on the availability of base- flow discharge measurements at the site, location of nearby gaged sites on the.
Low streamflow estimates are required for a variety of water resource management purposes. When a historic streamflow record is available, low streamflow estimates may be obtained by a parametric or nonparametric frequency analysis. When no historic discharge is available, techniques for estimating low streamflow statistics are limited. For most application, regional . In a more recent study, Mohamoud () attempted to predict daily streamflow in the Appalachian region by sequencing constructed FDCs with streamflow at a gaged reference site. In this study Mohamoud compared flow values predicted from his FDC method, and from various forms of the area ratio method, to the actual flow values in the study streams. the discharge measurements from 8 of the ungaged sites and discharge from 5 streamflow-gaging stations with fewer than 5 years of record with discharge data from streamflow-gaging stations with extended records. Relations between dis charge at three of the ungaged sites and the monthly streamflow data at nearby gages could not. Low-flow measurements at 63 partial-record and miscellaneous streamflow-measurement sites during surveys in –09 are used with concurrent flows at continuous streamflow-gaging stations (index sites) within the U.S. Geological Survey network to estimate the low-flow metric Q 7,10 at each measurement site (Q 7,10 is defined as the lowest.