| Abstract: | Analysis of streamflow measurements and continuous records of streamflow provided insight into interaction of the groundwater system with the Clackamas River in northwestern Oregon. This report assesses gains and losses of the Clackamas River based on streamflow measurements made during previous hydrologic studies, decades of continuous streamflow data, and a detailed suite of streamflow measurements made in September 2006. Gains and losses were considered significant if, after accounting for tributary inflows and withdrawals, the difference in streamflow from a measurement site to the next site downstream exceeded the streamflow measurement uncertainty. Streamflow measurements made in 1987, 1992, and 1998 indicated minor gains and losses. Comparison of continuous records of late summer streamflow of the Clackamas River at Estacada to sites at Clackamas and Oregon City indicated gains in some years, and no losses. Analysis of streamflow measurements of the Clackamas River from Estacada to Oregon City during low-flow conditions in September 2006 enabled an estimation of gains and losses on a reach-by-reach scale; these gains and losses were attributable to the geomorphic setting. During late summer, most groundwater discharge occurs upstream of Estacada, and groundwater contributions to streamflow downstream of Estacada are minor. |
| Genre: | USGS Numbered Series |
| ProdID: | 70006064 |
| Citation Author: | Lee, Karl K. |
| Citation Contributing Office: | Oregon Water Science Center |
| Citation Datum: | NAD 83 |
| Citation Day: | |
| Citation Edition: | |
| Citation Editor: | |
| Citation End Page: | 16 |
| Citation Issue: | |
| Citation Keywords: | |
| Citation Language: | English |
| Citation Larger Work Title: | |
| Citation LatN: | 0453000 |
| Citation LatS: | 0450000 |
| Citation LonE: | -1213000 |
| Citation LonW: | -1230000 |
| Citation Month: | |
| Citation No Pagination: | N |
| Citation Number Of Pages: | 20 |
| Citation Online Only Flag: | |
| Citation Phsyical Description: | iv, 16 p. |
| Citation Projection: | State Plane, Zone 5076 |
| Citation Public Comments: | Prepared in cooperation with the Clackamas River Water Providers and Clackamas County Water Environment Services? |
| Citation Publisher: | U.S. Geological Survey |
| Citation Series: | Scientific Investigations Report |
| Citation Series Code: | SIR |
| Citation Series Number: | 2011-5191 |
| Citation Search Results Text: | Seepage investigations of the Clackamas River, Oregon; 2011; SIR; 2011-5191; Lee, Karl K. |
| Citation Start Page: | i |
| Citation Volume: | |
| Citation Year: | 2011 |
| Type: | citation/reference |
| Text: | Seepage investigations of the Clackamas River, Oregon; 2011; SIR; 2011-5191; Lee, Karl K. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/sir_2011_5191.jpg |
| URL (INDEX PAGE): | http://pubs.usgs.gov/sir/2011/5191/ |
| Date Other: | Mon, 28 Nov 2011 00:00 -0600 |
| Publisher: | U.S. Geological Survey |
