GJN10021 DeltaPonds-FishMonitoring-RFP-v3.docx

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photo on page 1), however subsequent development filled in this area, leaving a remnant slough that was hydrologically disconnected from the river, except during extreme flood events. The 2010 construction created year-round backwater habitat for a reach of approximately 1,000 linear feet. In 2011 this backwater habitat will be further enhanced by connecting this slough to a large pond upstream through the excavation of an additional 1,650 linear feet of channel. The upstream pond is connected to the Willamette River year round and the additional channel excavation will allow flow through Heron Slough annually in the fall, winter, and spring. For the purposes of this RFP, Heron Slough is considered part of the Delta Ponds system and shall be included in all sampling efforts. Species to Benefit Spring Chinook salmon in the upper Willamette River were listed as threatened under the federal Endangered Species Act by NOAA in 1999. Spring Chinook salmon were once present in significant numbers in the upper Willamette River. They spawned in gravel beds in the upper reaches of the Middle Fork, as well as some of the major tributaries, pausing to rest and feed in side channel habitat from the confluence of the Middle and Coast Forks downstream. The building of Dexter dam eliminated over 90% of the spawning habitat. These changes to habitat certainly played a big role in the decline of these salmon. In addition to the loss of spawning habitat, the Willamette River system has faced a dramatic loss of side channel/floodplain rearing habitat for juvenile Chinook. Dams, dikes, levees, fill, and development have resulted in a significantly channelized river. Braided side channels, floodplains and backwater habitat have been lost. The Delta Ponds project directly addresses the loss of habitat by reconnecting critical side channel and floodplain habitat to the mainstem Willamette River. The Delta Ponds project was identified as a viable project in part because of the intactness of a mile-long remnant slough that connects the northern-most ponds to the Willamette River and the relative ease with which the ponds could be connected to each other and to the river at the southern (upstream) end. The Delta Ponds complex, now fully reconnected to the Willamette, will provide 2.2 miles of slow moving ponds and sloughs where juvenile Chinook can retreat from the fast moving mainstem to rest and regain their strength before continuing downstream. Furthermore, the conversion of steep banks to gradually sloping riparian benches will allow the establishment of more extensive and diverse emergent, wetland, and riparian habitat, which will provide optimum cover and food for overwintering juvenile salmon. By increasing access to food and shelter resources provided by this type of habitat, survival of juvenile Chinook will be substantially enhanced as they make their way to the ocean, contributing to overall recovery of this species. In addition to juvenile spring Chinook salmon, several other diadromous and resident fish species of special concern may benefit from enhanced side channel habitat, including Pacific lamprey and Oregon chub (Federal endangered species status: endangered and State status: critical).