| Abstract: | Channelization on Turkey Creek and its receiving stream, the South Fork Big Nemaha River, has disturbed the equilibrium of Turkey Creek and has led to channel-stability problems, such as degradation and channel widening, which pose a threat to bridges and land adjacent to the stream. As part of a multiagency study, the U.S. Geological Survey assessed channel stability at two bridge sites on upper and middle portions of Turkey Creek by analyzing streambed-elevation data for gradation changes, comparing recent cross-section surveys and historic accounts, identifying bank-failure blocks, and analyzing tree-ring samples. These results were compared to gradation data and trend results for a U.S. Geological Survey streamflow-gaging station near the mouth of Turkey Creek from a previous study. Examination of data on streambed elevations reveals that degradation has occurred. The streambed elevation declined 0.5 m at the upper site from 1967-97. The streambed elevation declined by 3.2 m at the middle site from 1948-97 and exposed 2 m of the pilings of the Nebraska Highway 8 bridge. Channel widening could not be verified at the two sites from 1967-97, but a historic account indicates widening at the middle site to be two to three times that of the 1949 channel width. Small bank failures were evident at the upper site and a 4-m-wide bank failure occurred at the middle site in 1987 according to tree ring analyses. Examination of streambed-elevation data from a previous study at the lower site reveals a statistically significant aggrading trend from 1958-93. Further examination of these data suggests minor degradation occurred until 1975, followed by aggradation. |
| Genre: | Conference Paper |
| ProdID: | 70021313 |
| Citation Author: | Rus, David, L.; Soenksen, Philip, J. |
| Citation Contributing Office: | |
| Citation Datum: | |
| Citation Day: | |
| Citation Edition: | |
| Citation Editor: | |
| Citation End Page: | 428 |
| Citation Issue: | |
| Citation Keywords: | |
| Citation Language: | English |
| Citation Larger Work Title: | International Water Resources Engineering Conference - Proceedings |
| Citation LatN: | |
| Citation LatS: | |
| Citation LonE: | |
| Citation LonW: | |
| Citation Month: | |
| Citation No Pagination: | |
| Citation Number Of Pages: | 6 |
| Citation Online Only Flag: | |
| Citation Phsyical Description: | |
| Citation Projection: | |
| Citation Public Comments: | |
| Citation Publisher: | ASCE |
| Citation Series: | |
| Citation Series Code: | |
| Citation Series Number: | |
| Citation Search Results Text: | Channel stability of Turkey Creek, Nebraska; 1998; Conference Paper; International Water Resources Engineering Conference - Proceedings; Rus, David, L.; Soenksen, Philip, J. |
| Citation Start Page: | 423 |
| Citation Volume: | 1 |
| Citation Year: | 1998 |
| Type: | citation/reference |
| Text: | Channel stability of Turkey Creek, Nebraska; 1998; Conference Paper; International Water Resources Engineering Conference - Proceedings; Rus, David, L.; Soenksen, Philip, J. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg |
| Date Other: | Thu, 1 Jan 1998 00:00 -0600 |
| Publisher: | ASCE |
