| Abstract: | The report presents techniques used for estimating 7-day 2-year (7Q2) and 7-day 10-year (7Q10) flows at continuous-record streamflow-gaging stations, partial-record stations, and ungaged sites on streams in Massachusetts. A two-parameter log-normal probability distribution was used to compute low flows at 31 continuous-record stream-flow-gaging stations. Graphical and mathematical techniques were used to estimate low flows at partial-record stations. Regional regression techniques commonly are used to estimate 7Q2 and 7Q10 flows at ungaged stream sites. The development and application of a low-flow regression model is described. The model contains two parameters, mean and standard deviation, computed from separate regression equations that use total drainage area and basin relief as independent variables. The coefficients of determination of the mean and standard deviation regression equations are 0.964 and 0.960, respec- tively; the percentage of standard error of the regression of each equation are 35 and 34, respec- tively. The model is applicable for basins in Massachusetts having a drainage area of 5 to 150 square miles, a slope of less than 4 percent, and an area of stratified drift greater than 4 percent of the total drainage area. A computer program is presented that can be used to compute 7Q2 and 7Q10 flows and the 95-percent intervals of confidence and prediction for a given basin. |
| Genre: | USGS Numbered Series |
| ProdID: | 29373 |
| Citation Author: | Risley, J. C. |
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| Citation Language: | ENGLISH |
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| Citation Phsyical Description: | iv, 29 p. :ill., maps ;28 cm. |
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| Citation Publisher: | U.S. Geological Survey ;
USGS Earth Science Information Center, Open-File Reports Section [distributor], |
| Citation Series: | Water-Resources Investigations Report |
| Citation Series Code: | WRI |
| Citation Series Number: | 94-4100 |
| Citation Search Results Text: | Estimating the magnitude and frequency of low flows of streams in Massachusetts; 1994; WRI; 94-4100; Risley, J. C. |
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| Citation Year: | 1994 |
| Type: | citation/reference |
| Text: | Estimating the magnitude and frequency of low flows of streams in Massachusetts; 1994; WRI; 94-4100; Risley, J. C. |
| URL (THUMBNAIL): | http://pubs.usgs.gov/wri/1994/4100/report-thumb.jpg |
| URL (DOCUMENT): | http://pubs.usgs.gov/wri/1994/4100/report.pdf |
| Date Other: | Wed, 1 Feb 1995 00:00 -0600 |
| Publisher: | U.S. Geological Survey ;
USGS Earth Science Information Center, Open-File Reports Section [distributor], |
