Base-flow index grid for the conterminous United States

Metadata Updated: May 12, 2018

This 1-kilometer raster (grid) dataset for the conterminous United States was created by i nterpolating base-flow index (BFI) values estimated at U.S. Geological Survey (USGS) streamgages. Base flow is the component of streamflow that can be attributed to ground-water discharge into streams.

Access & Use Information

License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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Dates

Metadata Date November 8, 2004
Metadata Created Date December 2, 2017
Metadata Updated Date May 12, 2018
Reference Date(s) January 1, 2003 (publication)
Frequency Of Update notPlanned
Frequency Of Update notPlanned

Metadata Source

Harvested from DOI CKAN Harvest Source

Graphic Preview

illustration of data set

Additional Metadata

Resource Type Dataset
Metadata Date November 8, 2004
Metadata Created Date December 2, 2017
Metadata Updated Date May 12, 2018
Reference Date(s) January 1, 2003 (publication)
Responsible Party U.S. Geological Survey (Point of Contact)
Contact Email
Access Constraints Use Constraints: The BFI grid was interpolated from BFI point values estimated for USGS streamgages (Wolock, 2003a). These point values were computed using an automated hydrograph separation computer program called the BFI program (Wahl and Wahl, 1988; 1995). Regarding this computer program, the BFI Web page (http://www.usbr.gov/pmts/hydraulics_lab/twahl/bfi/index.html) states: "The BFI program was developed to make the base-flow separation process less tedious and more objective. The program implements a deterministic procedure proposed in 1980 by the British Institute of Hydrology. The method combines a local minimums approach with a recession slope test. The program estimates the annual base-flow volume of unregulated rivers and streams and computes an annual base-flow index (BFI, the ratio of base flow to total flow volume for a given year) for multiple years of data at one or more gage sites. Although the method may not yield the true base flow as might be determined by a more sophisticated analysis, the index has been found to be consistent and indicative of base flow, and thus may be useful for analysis of long term base-flow trends. Users should be very cautious about using methods such as this for short-term storm events or for locations where streamflow is affected by upstream regulation, such as reservoir releases. In general, the method interprets most regulated releases as base flow. If the program is used for regulated streams, the effects of regulation must be carefully accounted for through manual adjustment of the program output." The base-flow index grid can be used to estimate natural recharge to ground water. (See Supplemental_Information.) The base-flow index approach to estimating ground-water recharge is likely to underestimate "true" recharge in areas where irrigation is used extensively and also in areas where ground-water evapotranspiration is significant. More details about the approach and its limitations can be found in Wolock (2003b). Use Constraints References: Wahl, K.L., and Wahl, T.L., 1988, Effects of regional ground-water declines on streamflows in the Oklahoma Panhandle, in Proceedings of Symposium on Water-Use Data for Water Resources Management: Tucson, Arizona, American Water Resources Association, p. 239-249, information available on the World Wide Web, accessed March 25, 2003, at URL http://www.usbr.gov/pmts/hydraulics_lab/twahl/bfi/bfi_beaver_river.pdf Wahl, K.L., and Wahl, T.L., 1995, Determining the flow of Comal Springs at New Braunfels, Texas, in Proceedings of Texas Water '95, August 16-17, 1995, San Antonio, Texas: American Society of Civil Engineers, p. 77-86, information available on the World Wide Web, accessed March 25, 2003, at URL http://www.usbr.gov/pmts/hydraulics_lab/twahl/bfi/texaswater95/comalsprings.html Wolock, D.M., 2003a, Flow characteristics at U.S. Geological Survey streamgages in the conterminous United States: U.S. Geological Survey Open-File Report 03-146, digital dataset, available on the World Wide Web, accessed June 30, 2003, at URL https://water.usgs.gov/lookup/getspatial?qsitesdd Wolock, D.M., 2003b, Estimated mean annual natural ground-water recharge estimates in the conterminous United States: U.S. Geological Survey Open-File Report 03-311, digital dataset, available on the World Wide Web, accessed August 20, 2003, at URL https://water.usgs.gov/lookup/getspatial?rech48grd, Access Constraints: None
Bbox East Long -65.346810
Bbox North Lat 51.608329
Bbox South Lat 22.860749
Bbox West Long -127.887748
Coupled Resource
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Regarding this computer program, the BFI Web page (http://www.usbr.gov/pmts/hydraulics_lab/twahl/bfi/index.html) states: \\\"The BFI program was developed to make the base-flow separation process less tedious and more objective. The program implements a deterministic procedure proposed in 1980 by the British Institute of Hydrology. The method combines a local minimums approach with a recession slope test. The program estimates the annual base-flow volume of unregulated rivers and streams and computes an annual base-flow index (BFI, the ratio of base flow to total flow volume for a given year) for multiple years of data at one or more gage sites. Although the method may not yield the true base flow as might be determined by a more sophisticated analysis, the index has been found to be consistent and indicative of base flow, and thus may be useful for analysis of long term base-flow trends. Users should be very cautious about using methods such as this for short-term storm events or for locations where streamflow is affected by upstream regulation, such as reservoir releases. In general, the method interprets most regulated releases as base flow. If the program is used for regulated streams, the effects of regulation must be carefully accounted for through manual adjustment of the program output.\\\" The base-flow index grid can be used to estimate natural recharge to ground water. (See Supplemental_Information.) The base-flow index approach to estimating ground-water recharge is likely to underestimate \\\"true\\\" recharge in areas where irrigation is used extensively and also in areas where ground-water evapotranspiration is significant. More details about the approach and its limitations can be found in Wolock (2003b). Use Constraints References: Wahl, K.L., and Wahl, T.L., 1988, Effects of regional ground-water declines on streamflows in the Oklahoma Panhandle, in Proceedings of Symposium on Water-Use Data for Water Resources Management: Tucson, Arizona, American Water Resources Association, p. 239-249, information available on the World Wide Web, accessed March 25, 2003, at URL http://www.usbr.gov/pmts/hydraulics_lab/twahl/bfi/bfi_beaver_river.pdf Wahl, K.L., and Wahl, T.L., 1995, Determining the flow of Comal Springs at New Braunfels, Texas, in Proceedings of Texas Water '95, August 16-17, 1995, San Antonio, Texas: American Society of Civil Engineers, p. 77-86, information available on the World Wide Web, accessed March 25, 2003, at URL http://www.usbr.gov/pmts/hydraulics_lab/twahl/bfi/texaswater95/comalsprings.html Wolock, D.M., 2003a, Flow characteristics at U.S. Geological Survey streamgages in the conterminous United States: U.S. Geological Survey Open-File Report 03-146, digital dataset, available on the World Wide Web, accessed June 30, 2003, at URL https://water.usgs.gov/lookup/getspatial?qsitesdd Wolock, D.M., 2003b, Estimated mean annual natural ground-water recharge estimates in the conterminous United States: U.S. Geological Survey Open-File Report 03-311, digital dataset, available on the World Wide Web, accessed August 20, 2003, at URL https://water.usgs.gov/lookup/getspatial?rech48grd\", \"Access Constraints: None\"]", "temporal-extent-begin": "1884-01-01", "contact-email": "dwolock@usgs.gov", "bbox-west-long": "-127.887748", "metadata-date": "2004-11-08", "dataset-reference-date": "[{\"type\": \"publication\", \"value\": \"2003-01-01\"}]", "harvest_source_title": "DOI CKAN Harvest Source", "graphic-preview-description": "illustration of data set", "frequency-of-update": "notPlanned", "licence": "[\"Although this data set has been used by the U.S. Geological\\nSurvey, U.S. Department of the Interior, no warranty expressed or\\nimplied is made by the U.S. Geological Survey as to the accuracy\\nof the data and related materials. The act of distribution shall not \\nconstitute any such warranty, and no responsibility is assumed by \\nthe U.S. Geological Survey in the use of this data, software, or \\nrelated materials.\\n\\nAny use of trade, product, or firm names is for descriptive\\npurposes only and does not imply endorsement by the U.S.\\nGovernment.\"]", "metadata_type": "geospatial", "harvest_object_id": "86d6c840-7ca0-4d93-b36e-c8cdf8abd221", "responsible-party": "[{\"name\": \"U.S. Geological Survey\", \"roles\": [\"pointOfContact\"]}]", "temporal-extent-end": "2001-01-01", "spatial-data-service-type": "", "bbox-south-lat": "22.860749"}
Frequency Of Update notPlanned
Graphic Preview Description illustration of data set
Graphic Preview File https://water.usgs.gov/GIS/browse/bfi48grd.jpg
Graphic Preview Type jpg
Guid
Harvest Object Id 0e4e071c-12bc-4a72-9588-002ad3456ceb
Harvest Source Id 1f3ebea5-58d2-4aaa-85a0-e7ebda3074e7
Harvest Source Title DOI CKAN Harvest Source
Licence Although this data set has been used by the U.S. Geological Survey, U.S. Department of the Interior, no warranty expressed or implied is made by the U.S. Geological Survey as to the accuracy of the data and related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the U.S. Geological Survey in the use of this data, software, or related materials. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Metadata Language
Metadata Type geospatial
Progress completed
Spatial Data Service Type
Spatial Reference System
Spatial Harvester true
Temporal Extent Begin 1884-01-01
Temporal Extent End 2001-01-01

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