TA1 Developing Suspended and Bedded Sediments Criteria
256 Portland Ballroom
8:00 AM - 12:00 PM, Tuesday
() Development of Fine Sediment listing benchmark for the State of Oregon.
Drake, Doug1, Hafele, Rick1, 1 Oregon Dept. of Environmental Quality, Portland, OR, USA
ABSTRACT- The Oregon Department of Environmental Quality has developed benchmarks for excess fine sediment in wadeable streams as part of the Section 305(b) requirements of the Clean Water Act. Data from Environmental Monitoring and Assessment Program (EMAP) style probabilistic and hand-picked reference stream sampling was used to set ecoregion benchmarks. Wolman pebble count data and relative bed stability metrics were analyzed with macroinvertebrate and vertebrate data to establish biological relevance. The reference condition for fine sediment from the physical habitat sampling concurred with the threshold for unimpaired biological condition. The process and results from the fine sediment benchmark development will be described.
Key words: relative bed stability, fine sediment, 305(b) listing, ecoregion