摘要: |
The U.S. Army Corps of Engineers - Portland District asked Pacific Northwest National Laboratory to re-analyze four years of fixed-aspect hydroacoustic data after the District made adjustments to spill discharge estimates. In this report, we present new estimates of all major fish-passage metrics for study years 2000, 2001, 2002, and 2004, as well as estimates for 2005. This study supports the Portland District and its effort to maximize survival of juvenile salmon passing Bonneville Dam. Major passage routes through Bonneville Dam include 10 turbines and a sluiceway at Powerhouse 1 (B1), an 18-bay spillway, and eight turbines at Powerhouse 2 (B2) and a sluiceway including the B2 Corner Collector. The original reports and all associated results, discussion, and conclusions for non flow-related metrics remain valid and useful, but effectiveness measures for study years 2000, 2001, 2002, and 2004 as reported in previous reports by Ploskey et al. should be superseded with the new estimates reported here. The fish-passage metrics that changed the most were related to effectiveness. Re-analysis produced spill effectiveness estimates that ranged from 12% to 21% higher than previous estimates in spring and 16.7% to 27.5% higher in summer, but the mean spill effectiveness over all years was only slightly above 1:1 (1.17 for spring and 1.29 for summer). Conversely surface-passage effectiveness decreased in the years this metric was measured (by 10.1% in spring and 10.7% in summer of 2002 and 9.5% in spring and 10.2% in summer of 2004). The smallest changes in the re-analysis were in project fish passage efficiency (0%-1%) and spill efficiency (0.9%-3.0%). / Supplementary Notes: Sponsored by Department of Energy, Washington, DC. / Availability Note: Order this product from NTIS by: phone at 1-800-553-NTIS (U.S. customers); (703)605-6000 (other countries); fax at (703)605-6900; and email at orders@ntis.gov. NTIS is located at 5285 Port Royal Road, Springfield, VA, 22161, USA. |