5.10 Grays Harbor Tributaries Ecological Region
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Ecological Regions: Grays Harbor Tributaries Ecological Region 5.10 Grays Harbor Tributaries Ecological Region 5.10.1 Overview The Grays Harbor Tributaries Ecological Region encompasses the tributaries that directly enter Grays Harbor (other than the Chehalis River) and the Wishkah River that enters the Chehalis River at RM 0 (Figure 5-19). This ecological region encompasses more than 600 square miles (nearly 385,000 acres) and represents approximately 22% of the overall Chehalis Basin. The ecological region is diverse, with drainages from the Olympic Mountains and lower Coast Range areas. The highest point in this ecological region is Gibson Peak at 4,390 feet. The Humptulips Important Features and Functions River arises in two forks within the Olympic National • The amount of tidally influenced Forest at about 3,000 feet in elevation and flows for freshwater wetland with Sitka spruce 60 miles to Grays Harbor. The Hoquiam River arises in swamp in the ecological region is unique in the basin and much different from the the low foothills of the Olympic Mountains in three deciduous-dominated forest in the forks at about 400 feet in elevation; the East Fork Chehalis River Tidal Ecological Region. Hoquiam River is the longest and flows for 17 miles. A • The maritime climate provides a year- significant part of the Middle Fork and West Fork round buffer to air (and water) temperatures. Hoquiam rivers are within the City of Hoquiam • The Humptulips River sub-basin municipal watershed. The Wishkah River arises in the characteristics are important and unique: foothills of the Olympic Mountains at about these feature a smaller percentage of the 1,200 feet in elevation; the upper watershed of the total length in tidewater, substantial spawning gravel, and close proximity to Wishkah River is within the City of Aberdeen’s the ocean. Old-growth forest in the upper municipal watershed, and a dam is located at RM 32.5 Humptulips River sub-basin has no for water supply. In the South Bay, several tributaries duplicate in the Chehalis Basin except in arise in the low coastal foothills, the largest of which small portions of the upper Wynoochee and Satsop rivers. are the Elk and Johns rivers, which arise at about • This ecological region is characterized by 500 feet in elevation and have a large percentage of several species that are either not seen or the system within the tidally influenced range. All of rarely seen elsewhere in the basin, the Grays Harbor tributaries are tidally influenced in including bull trout and eulachon, both of which are federally listed as threatened their lower miles. under the ESA. • There are significant hatchery influences The Grays Harbor Tributaries Ecological Region on wild fish that may include competition, geology is predominantly composed of volcanic and genetics, predation, disease, and fish sedimentary rocks of the Olympic Mountains and passage. (continues on next page) Coast Range and recent alluvium in the larger valleys Chehalis Basin Strategy 181 Aquatic Species Restoration Plan Ecological Regions: Grays Harbor Tributaries Ecological Region and lowlands. Part of the Humptulips River watershed Important Features and Functions is dominated by glacial deposits from the alpine (Continued) glaciation in the Olympic Mountains (WDNR 2010). • Stillwater-breeding amphibian habitats Precipitation is dominated by rainfall; however, seem limited at all elevations. This average annual precipitation varies from 75 to ecological region has the largest 100 inches in Aberdeen and around the lowlands to distribution of Cascade frog. Some of the best stream-breeding and stream- 100 to 200 inches in the upper half of the Humptulips associated amphibian habitats also occur in and Wishkah drainages (PRISM 2012). the headwaters of the Humptulips River. • Forested tidal slough areas of this ecological The Grays Harbor Tributaries Ecological Region is region are important habitat for the bird almost entirely within Grays Harbor County indicator species—great blue heron, barrow’s goldeneye, and wood duck. (380,063 acres, or 99%), with a very small portion within Pacific County (4,638 acres, or 1%). Cities and towns in this region include Humptulips, Ocean Shores, Westport, Hoquiam, and Aberdeen. Chehalis Basin Strategy 182 Aquatic Species Restoration Plan Figure 5-19 Grays Harbor Tributaries Ecological Region Map Olympic National bson Gi Park eek Cr ¤£101 Olympic National Forest Wynoochee Dam!(> Fish Collection!(> !Taholah Facility Humptulips ps !Moclips Hatchery ptuli ¡[ Hum er > Riv !( ! Stevens Creek Humptulips r e v Hatchery Dam i R h a k h s i ¡[W Mayr Bros. Rearing Pond k Wynoochee Deep Cree (!> System Failor Lake Dam ¡[ r C e vis r v Da e i e Fork SatsopWest River k R e e > h (!> c !( o City o n of Hoquiam y Dams W H o q Buzzard u ia Creek City m [ !(> Co-Op¡ of Hoquiam R kle i Win v Van Dam e ek r Cre Sylvia Lake Dam !(> !Ocean Shores Hoquiam ! ¡[Lake Aberdeen Aberdeen! Montesano! E Hatchery ¤£12 RM 0 Chehalis River s Surge Plain Natural Cheh ali Cosmopolis ! Rive r Area Preserve ERiver lis RM 10 ¡[ ha MillC e r Quigg h Westport e C e Net Pens k VU107 Lake Net ¡[ Pens !Westport J o h n s Elk River Ri ver NRCA ¤£101 Elk River Study Area Rivers and Streams E Mainstem Chehalis River Miles Ecological Region Park Other Public Land > Miles !( Dam " 0 6½ ¡[ Fish Hatchery 2019/11/08, 10:07 AM10:07 epipkin| 2019/11/08, Q:\Jobs\WA_OFM_1023\ChehalisBasinStrategy\Maps\AquaticRestoration\EcologicalRegions\AQ_Chehalis_EcologicalRegions_OVERVIEW_AerialPhoto_11x17P.mxd | N Aerial Photo Source: Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the GIS User Community Ecological Regions: Grays Harbor Tributaries Ecological Region 5.10.2 Historical Conditions and Changes Historical records for the pre-Euro-American settlement conditions are not available, but available GLO maps indicate that the Grays Harbor Tributaries Ecological Region was dominated by sinuous rivers with wetlands along the lower Humptulips River and note a significant channel change along the Wishkah River in 1871. Key changes that occurred in the Grays Harbor Tributaries Ecological Region following Euro-American settlement were timber harvest and industrial and urban development surrounding Grays Harbor (Aberdeen and Hoquiam) and the major transportation corridors (including Highway 101, railroad lines, SR 12, and SR 105). Similar to other parts of the basin, splash dams were used (see the description in Section 2.1). Several splash dams were known to have been used on both the East and West Fork Humptulips rivers and major tributaries such as Big Creek, and numerous splash dams were used on all forks of the Wishkah and Hoquiam rivers (Humptulips Historical Society 2018; WDF 1975; Wendler and Deschamps 1955). Numerous splash dams were also used on Newskah Creek. Road-, railroad-, bridge-, and timber-associated construction likely also moved and straightened some of the tributaries. The Washington Department of Fisheries (1975) noted that gravel mining occurred regularly in and adjacent to the Humptulips River and there were low flows in several tributaries. A natural falls at about RM 18 on the East Fork Humptulips River had a fish ladder installed. Municipal water dams and diversion on the Hoquiam River and its tributaries have hindered fish passage and reduced flows. The water supply dam and reservoir at RM 32 on the Wishkah River was not installed with fish passage, although it Natural and stable large wood is only present in is upstream of a natural falls. It appears that the dam a few protected locations in the upper West blocks access for steelhead to upstream areas. Fork Humptulips River. In the majority of the Grays Harbor Tributaries Ecological Region, the old-growth forest was logged, and splash dams Modeling conducted by NOAA (Beechie 2018) for the were used extensively on the East and West ASRP indicated moderate losses (about 20%) in marsh Fork Humptulips rivers, the Wishkah Ricer, and habitats in the Humptulips and Hoquiam river Newskah Creek to facilitate moving timber to floodplains and disturbance to many of the remaining markets. marshes. To support the ASRP analysis and EDT modeling, the SRT developed assumptions of the channel lengths and areas of floodplain habitat that were likely to be present in historical conditions. These assumptions were based on the GLO mapping from the late 1800s, more recent historical aerial photographs, and interpretation of current LiDAR data that show remnant channels and other floodplain features. The rivers in the Grays Harbor Tributaries Ecological Region are unconfined to partly confined and low gradient within narrow valleys in the upper areas and large, wide alluvial valleys in the lower extents. Chehalis Basin Strategy 184 Aquatic Species Restoration Plan Ecological Regions: Grays Harbor Tributaries Ecological Region Compared to historical conditions, the stream channel lengths do not appear to be significantly reduced, but side channels would have historically been far more prevalent, and the rivers could have had 3 to 8 times the area of frequently connected floodplain. Large wood has been removed from the channels throughout this region. 5.10.3 Current Conditions Current conditions in the Grays Harbor Tributaries Ecological Region reflect ongoing agricultural land Grays Harbor Tributaries Current Snapshot uses and residential and commercial development. Land cover is 53% coniferous forest, 19% scrub-shrub, Condition of Watershed Processes: 7% herbaceous,