The removal of two large dams on the Elwha River was completed in 2014 with a goal of restoring anadromous salmonid populations. Using observations from ongoing field studies, we compiled a timeline of migratory fish passage upstream of each dam. We also used spatially continuous snorkeling surveys in consecutive years before (2007, 2008) and after (2018, 2019) dam removal during summer baseflow to assess changes in fish distribution and density over 65 km of the mainstem Elwha River. Before dam removal, anadromous fishes were limited to the 7.9 km section of river downstream of Elwha Dam, potamodromous species could not migrate throughout the river system, and resident trout were the most abundant species. After dam removal, there was rapid passage into areas upstream of Elwha Dam, with 8 anadromous species (Chinook, Coho, Sockeye, Pink, Chum, Winter Steelhead, Summer Steelhead, Pacific Lamprey, and Bull Trout) observed within 2.5 years. All of these runs except Chum Salmon were also observed in upper Elwha upstream of Glines Canyon Dam within 5 years. The spatial extent of fish passage by adult Chinook Salmon and Summer Steelhead increased by 50 km and 60 km, respectively, after dam removal. Adult Chinook Salmon densities in some previously inaccessible reaches in the middle section of the river exceeded the highest densities observed in the lower section of the river prior to dam removal. The large number (>100) of adult Summer Steelhead in the upper river after dam removal was notable because it was among the rarest anadromous species in the Elwha River prior to dam removal. The spatial extent of trout and Bull Trout remained unchanged after dam removal, but their total abundance increased and their highest densities shifted from the lower 25 km of the river to the upper 40 km. Our results show that reconnecting the Elwha River through dam removal provided fish access to portions of the watershed that had been blocked for nearly a century.

The John F. BaldwinShip Channel (JFBSC) is part of the San FranciscoBay to Stockton,Califomia,NavigationProjectauthorizedby the Riverand HarborsAct of 1965 (Public Law 89-298). The JFBSC extendsfrom the GoldenGate northof the cityof San Francisco, throughSan Pablo Bay and the CarquinezStrait,and intoSuisunBay. The U.S. Army Corps of Engineers(USACE)-San FranciscoDistrict,isresponsible for the construction and maintenanceof the JFBSC. Planned improvementsto the JFBSC includedeepeningalongan approximately28-mi sectionof the channelin the West Richmond,PinoleShoal,and CarquinezStraitreachesto a depthof-45 ft mean lowerlowwater (MLLW). Disposaloptionsfor sedimentproposedfor removalfrom these improvement areas includeaquaticdisposal withinSan FranciscoBay or at an open-oceansite, marshor wetlandsconstruction, and uplandsdisposal. To assistthe USACE in determiningwhetherthe proposeddredgedmaterialis suitablefor unrestricted, unconfinedopen-oceandisposal, Battelle/MarineSciencesLaboratory(MSL) preparedthis Tier I report. Technicalguidanceforevaluatingthe suitabilityof dredgedmaterials for ocean disposalis providedin the 1991 TestingManual (Evaluation of Dredged Mater_al Proposed for Ocean Disposal-Testing Manual, EPA-503/8-91/001), knownas the =Green Book." The Green Bookprovidesa tiered approachfor testingthe suitabilityof dredged materials throughchemical,physical, and biological evaluations. The Tier I reportprimarily summarizes existinginformationon sedimentcontamination and toxicitypotential,identifiescontaminants of concem,and determinesthe needfor furthertesting(i.e.,Tiers II-IV). Basedon the findingsof thisTier I report, sedimentsthatwouldbe removedduringPhase III improvements to the JFBSCfail to meet the three suitabilitycriteriafor unrestricted, unconfined open-oceandisposalthatare delineatedin the Green Book. The firstcriterionis notmet because fine-grainedsedimentscomprisea significant fractionof the bottommaterialin some areas of the JFBSC, and becausethismaterialis notexposedto highcurrentor wave energy. Dredged materialfrom the JFBSC is notbeingproposedfor beach nourishment; therefore,the second criterionis notmet. JFBSC sedimentsdo notmeetthe thirdcriterionbecause,althoughthey may be substantiallysimilarto substratesat severalof the proposeddisposalsites,they are from an area that historically has experiencedloadingof contaminants, whichtoxicologystudieshave shownhave the potentialto resultin acutetoxicityor significant bioaccumulation. Sufficientinformationon contaminant concentrations in JFBSCsedimentsexiststo conclude that dredgedmaterialsfrom the JFBSC maypose _ !skto sensitivemarineorganisms. Informationon persistence, bioavailability, and relativebioaccumulation potentialare lacking; therefore,additionaltestingof sedimentsunderTier III is warranted. ACKNOWLEDGMENTS Informationreviewedand incorporatedin this reportwas providedby a numberof individuals.We especiallywishto recognizeKerryGuy of the USACE-San FranciscoDistrict;Ed Longand Don MacDonaldof Seattle/NOAA;Dale Bowyer,Mike Carlin,and Tom Gande...

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