Chimacum Creek Stream Restoration:
A Community Partnership Model
by Barbara Nightingale
 

BASIN

Chimacum Creek Watershed, located in the Puget Lowland Ecoregion, is the largest basin on the Quimper Peninsula. It is located on the northeastern side of the Olympic Peninsula in western Washington and drains 37 square miles of land with 29.5 miles of low gradient (0 to 4%) streams. The stream has a "Y" configuration splitting into east and west forks at Rivermile 3 and empties into Port Townsend Bay in northern Puget Sound. The headwaters, originating in forested hills of glacial outwash material, have a slightly higher stream gradient than the lowlands and carry large loads of fine sediment downstream. The forks and mainstem have lower gradients and channel substrates consisting of silt, sand, peat and gravel. Lying in the rain shadow of the Olympic Mountains, it has a low ratio of average annual discharge to watershed area compared to other streams on the Olympic Peninsula (Lichatowich 1993). Although the basin lies within this rain shadow, the flow of groundwater to the stream has historically provided adequate stream flow and habitat conditions to support the natural development of  native salmon populations.

SALMON AND STREAM HISTORY

Prior to euro-american settlement in the 1850's (Lichatowich 1993), the creek riparian areas were thickly forested with spruce, cedar, hemlock and fir with streams meandering through swamps, wet prairies and beaver ponds. By the turn of the century, the uplands were logged and the land surrounding the creek was fast being converted to farming use. The creek and its associated wetlands were drained, ditched and channelized. This removal of riparian vegetation has reduced the stream's productivity and ability to support its once abundant native salmon populations. Pacific salmon (Oncorhynchus spp.) are culturally and economically important to the region. The combined effects of harvesting, hatcheries and habitat degradation have drastically reduced the abundance of salmon in the northwest. Habitat degradation has caused the disappearance of 40% of the historic salmonid breeding ranges in Puget Sound (Bledsoe et al. 1989) reflecting a substantial cultural, socioeconomic and biologic loss. Given that salmonid production requires high quality, unpolluted waters, their demise reflects a significant loss in the quality of our streams and rivers. Habitat loss is repeatedly identified as a significant contributor to the declining status of individual salmonid species (Nehlsen et al 1991; Bjornn and Reiser 1992; Cooper and Johnson 1992; Lichatowich 1989; WDF 1992, 1993; Trotter et al. 1993; NMFS 1997). The land uses impacting this watershed typify this region's rural use impacts to watersheds.  The natural conditions of the creek once supported anadromous runs of native coho, summer and fall chum and steelhead populations. Small mixed and native coho, summer chum and steelhead are still supported along with a resident population of cutthroat. The status of coho and summer chum are of particular concern. The basin's unique combination of climate, vegetation and geology  has allowed these two species, with very different stream resident lengths and habitats, to evolve within this one stream. Over the last 100 years, the basin's variety of land uses has significantly compromised the stream's ability to support these once robust salmonid populations. These impacts are not irreversible but require time, patience and a wide base of community support and cooperation to reverse. Support for moving towards the reversal of impacts is reflected in the 1994 Dungeness-Quilcene Water Resources Management Plan completed by a diverse group of stakeholders including Jefferson County, Tribes and a variety of environmental, agricultural and development interests. the plan specifically recommends that "salmon habitat which has been destroyed or degraded in eastern Jefferson County should be enhanced and restored, and areas not yet impacted should be maintained and protected."

For natural spawning salmon, the competitive battle determining the genetic heritage of a particular salmon run consists of females competing for the best spawning sites and males competing for access to spawning females. In this way, they each insure the carrying of their seeds, the seeds of the strongest survivors, to future generations. The degree to which an individual male is able to outcompete smaller, less dominant males for the opportunity to position next to as many spawning females as possible lays the groundwork for his ability to influence the genetic legacy of his population. The degree to which a given female successfully locates those hydrologic and geophysical features that can provide optimum survival conditions for her offspring helps determine both the male and female's ability to influence the genetic legacy of their population and pass on their "survivor" traits. The trip is a long and treacherous one. From their natal stream, survivors will travel thousands of kilometers out to sea and back to their natal stream to spawn. Although, a chum female may lay ~3,000  eggs, the survival of fry to maturity averages a survival rate of only 0.3% to 3.2% for wild chum, varying with the region and the year. The impacts of harvesting, hatcheries and habitat degradation have combined to reduce their survival rate to a level where the ability of some Puget sound populations to sustain their own populations are threatened (NMFS 1995; 1997; 1998). Given these tough survival odds, it is essential that all survival  impacts be addressed. As we become aware of decadal and interannual fluctuations in climatic conditions, ocean productivity and estuarine productivity, the need to reverse habitat degradation  that compromises any part of the salmonid life-history becomes apparent. When ocean productivity is reduced, freshwater and estuarine systems cannot also be compromised and still retain self-sustaining populations.

CHIMACUM COHO

The coho return to spawn from early November to late January in select areas upstream including headwater areas. They appear to seek out nest sites near groundwater seepage and favor areas  near riffles and pools. By digging nests near pools and riffles, they are able to enhance the percolation of water through  the nest delivering essential oxygen to the eggs and alevins. Upon emerging from the gravels, the young fry spend their first 18 months of life rearing in select stream habitats throughout the watershed before migrating to sea. Juvenile coho rely upon drifting organic materials, primarily insects for prey. Their winter rearing habitat is usually associated with abundant cover and their summer rearing habitat tends to consist of pools and ponds associated with slow moving backwater and shallow, slow moving stream margins. As they grow, they move to deeper and larger pools with abundant cover (Reeves, et al. 1989; T. Nichelson, 1992 unpubl. data). Occupying slow moving waters allows them the ability to capture prey with minimum energy expenditure (Mundie 1969). Small, densely shaded stream areas provide rich sources of insect prey (Chapman 1965). Riffle areas maximize food production with the associated pools providing optimum conditions for coho holding and feeding (Mundie 1969).  This extended period of stream residence and reliance upon stream productivity makes them particularly vulnerable to water quality degradation and habitat losses caused by channelization, increased nutrient loads and vegetation changes. The stream habitats are an important link to adult survival. For unlike the chum, those coho that enter marine waters in their first spring or summer of life do not survive to the adult stage (Crone and Bond 1976).

The channelization of Chimacum creek goes back to the early  twentieth century. A diagram overlaying the creek's 1920 shape with its 1956 shape demonstrates a history of efforts to channelize the creek's shape and straighten its natural meandering shape. The combined effects of  stream channelization, removal of native riparian vegetation, beaver ponds, and drainage of swamp areas have reduced the area and quality of rearing habitats within the stream. Vegetation removal reduces stream complexity and prey abundance by removing inputs of large woody debris  and its associated insect prey and holding pools. This combined reduction in prey abundance and holding pools increases the energy expense associated with prey capture. Coho abundance is believed to be limited by the number and availability of suitable territories (Larkin 1977). Structurally complex streams with logs, bushes and stones for fish to use for holding, rest and shelter have shown to support larger numbers of fry than streams without such complexities (Scrivener and Andersen 1982).

Compared to historical levels, the stream's available high quality habitat have been  reduced by over 90%  by the history of land use practices along the stream (Bahls and Rubin 1996). This reduced channel complexity, once provided by stream meandering and woody debris combined with increased deposition of fine sediments to the spawning beds has greatly reduced the ability of the coho to naturally recover. When key elements to a stream’s habitat elements are depleted by the loss of woody debris and an increase in fine sediments, its carrying capacity will most likely remain depressed until those key elements are restored (Bilby 1988; Gore and Shields 1995). The stream’s carrying capacity for coho is measured by its ability to offer diverse rearing habitat for different seasons, winter and summer, and spawning grounds that can support abundant emerging alevins. Compared to historical levels, the stream’s coho summer and winter rearing habitat have been reduced by over 90% (Bahls and Rubin, 1996). The increased fine sediment deposition from upstream road failures has also reduced the stream’s coho spawning area. The lack of surrounding vegetation has also degraded the quality of stream habitat with high stream temperatures and low dissolved oxygen levels. Increased stream temperatures coupled with the invasion of non-native plants, such as reed canary grass, increased nutrient loads from farming and decreased wetlands, available for nutrient exchange, have very likely contributed to the existing low levels of dissolved oxygen. In addition to such habitat degradations, impassable culverts block migrating adults from potential spawning habitat and juveniles from potential rearing habitats. Fish production is dependent upon both food availability and suitable habitat (Chapman 1966). Higher levels of production occur when both prey resource abundance and habitat quality are simultaneously high rather than one being depressed and the other elevated (Warren et al. 1964, Mason 1976). Although salmon consistently show a strong adaptive capacity to recover from natural episodic events, this cumulative degradation of habitats required to support critical life history periods blocks their ability to recover without well coordinated restoration efforts.

CHIMACUM SUMMER CHUM

The chum life cycle does not include a period of extended stream residence. Upon emergence from the gravel, the chum fry immediately outmigrate to marine waters where they rely on the Puget Sound estuary to meet their critical growth needs. The chum life cycle in Chimacum Creek begins between August and October when returning female spawners select and dig nest sites within the first mile from the creek mouth. Chum females prefer spawning sites near upwellings or immediately above turbulent areas to insure adequate oxygen for egg survival. Upon selecting her site, she digs her nest and sweeps it clean of fine sediments that may limit oxygen to the eggs and suffocate her young. Following spawning, the female will bury the eggs and guard against their disturbance to her death. Both the eggs and the alevins require oxygen while they incubate in stream gravels. During this period, they are highly susceptible to any deposition of fine sediments. Subsequent removal of vegetation and ensuing land erosion into the streambed can significantly reduce their chances of survival. When upstream road failures and chronic streamside erosion combine, a dangerously high level of fine sediments become deposited in the lower streambed. These types of events have resulted in high levels of sand and silt near the creek mouth. It is believed that prior to 1991, two such road failures contributed to existing cumulative conditions ultimately leading to the extirpation of the creek's native chum summer run.

Prior to 1991, following the combined effects of these two episodic events, the stream’s native chum run was extirpated  It is believed that the history of the cumulative effects of chronic fine sediment deposition to this downstream spawning area from upstream land use practices made the chum spawning beds particularly vulnerable to these two large episodic events. These large episodic events, a logging road failure in the upper watershed and a road culvert failure at Rivermile 2 raised the percentage of fines to over 20%. Studies have demonstrated that high levels of chum egg survival and alevin emergence require that less than 20% of the spawning bed substrate consist of fine sand or silt sediments (Koski 1966,1975).  In 1996 Bahls and Rubin (1996) estimated, by visual stream survey, that the fines in the chum spawning area consisted of 40-60% of fines, sand or silt, in the chum spawning areas. In 1993 sediment studies sediment studies using a McNeil sampler and Timber, Fish and Wildlife guidelines (TFW) was undertaken to sample riffle crests in the chum spawning area used the definition of fines as 0.0mm-0.84mm and found the mean percentages to range from 19.7% to 28.1%.  They also found the percent of fines less than 0.106mm in size to range between mean values of 27.5% and 32.9% (Kennedy 1993). In studies at Big Beef Creek on Hood Canal, Koski (1966, 1975) found that alevin survival in gravels with sands between 3.327mm and 0.105mm, was highest in gravels containing 11-30% sand. He found each 1% increase in sand to reflect a 1.26% decrease in survival to emergence. Koski considered the amount of fines to reflect an index of the "living space" or percentage of voids available for the developing eggs and alevins. Koski found intragavel dissolved oxygen content reduced when fines exceeded 35%. A higher percentage of sand in the gravel resulted in an earlier emergence, a higher level of prematurity and smaller fry size. Similarly, studies have found that a substrate composition of 60% in fine sediments reduces embryo survival to near zero for at least five species of Pacific salmon (Tappel and Bjornn 1983; Irving and Bjornn 1984).

THE ESTUARY - PORT TOWNSEND BAY EELGRASS HABITAT

Following emergence from the streambed, at sizes of 30-50mm, chum fry migrate from their natal stream to the estuary. This period of estuarine residence is one of critical growth and high mortality risk (Bax 1983a, 1983b; Whitmus 1985). While their small size magnifies their predation risk, their ability to meet growth needs will have a determining effect on their ability to survive ocean migration.The stresses they encounter upon entering these estuarine waters are immense. Their entry into saltwater triggers a series of  hormonal and rapid physiologic changes transforming them into smolts and adapting them to saltwater. Due to their small size and ongoing physiologic changes, their predation risk is high.  Simenstad's work in Hood Canal (Simenstad et al. 1980, Simenstad and Salo 1980; Simenstad et al 1982) strongly suggests the existence of estuarine carrying-capacity limitations. Such growth limitations can reduce their ability to meet critical growth needs and counter predation risks. In studies on Hood Canal chum, Simenstad (1978,1980) found that chum selectively prey on the harpacticoid copepod found in very high quantities in eelgrass beds. The study findings suggest a link between the availability of harpacticoid crops, migration speed and fish size. Smaller crops of harpacticoids appeared to link to faster migration speeds and smaller fish size (Simenstad et al. 1978, 1980). They also found the harpacticoid crops in eelgrass meadows to average eight times the magnitude found in other nearshore habitats (Simenstad et al. 1978,1980). The affinity of the harpacticoid for eelgrass lies in the rich prey resources provided by epiphytic communities on and around the eelgrass shoots and rhizomes. The harpacticoid feeds on diatoms, detritus and microbial communities that make up the brown epiphytic felt accumulating on its shoots.

The immediate outmigation of small juvenile chum from Chimacum Creek make them particularly reliant upon the shallow nearshore habitat just off the shores of the creek mouth in the Port Townsend Bay estuary. The eelgrass beds of Port Townsend Bay are an integral part of the estuary's carrying capacity for juvenile chum. The importance of existing eelgrass beds is magnified by Puget Sound's natural fjord bathymetry and increasing shoreline development. The  glacier-carved steep sloping shoreline bathymetry of Puget sound naturally limits the shallow vegetated habitat supporting juvenile salmon prey resources to a narrow band parallel to the shoreline. This natural limitation to the areal extent of the shallow nearshore habitat has been exacerbated by the impacts of shoreline development that appear to have further reduced the type and quantity of available nearshore habitat (Thom and Hallum 1991; Saunders et al. 1991).

Shoreline development can impact eelgrass beds by changing the nature of nearshore vegetation and its associated communities. Hard sea walls and riprap change the slope of the beach by changing wave energy patterns and stopping the addition of sediments to the beach. These hard systems of erosion control actually increase the loss of sediments and beach in front of them. This increase in slope results in increased water depth at the shoreline and reduces the area of exposed beach on low tide. Such changes in slope in turn change what plants and animals can make a living along the beach. This reduces the ability of eelgrass to grow and reproduce along the shoreline (Shreffler et al.1995). This loss of eelgrass communities has a ripple effect on the biologic communities available to juvenile chum as they forage in this nearshore habitat. Aerial photos of the shoreline adjacent ot the creek's mouth display development encroaching towards the shoreline area.

Fine sediments transported downstream and deposited in nearshore habitat at the mouth of the stream can bury eelgrass beds. Excess nutrients deposited in nearshore estuarine habitats can stimulate epiphytic growth on eelgrass shoots limiting the availability of light for plant growth and survival. Excess nutrients also set up conditions favorable to the increased growth of ulva which is known to deprive eelgrass plants of the necessary light and oxygen required for growth and reproduction setting up an anoxic condition that limits the survival and reproduction of eelgrass and favors the spread of ulva. Monitoring changes in nutrient loads to the estuary, eelgrass versus ulva ratios, sediment deposition loads and tidal prism parameters are important elements to include in a comprehensive stream monitoring system.

Data collected by the Washington State Department of Health over the past 5 years show that the marine waters at the mouth of Chimacum Creek meet water meet the water quality standards required for approved shellfish growing. Similarly, water quality data for the year 2000 collected by the Jefferson County Conservation District demonstrated that the station immediately downstream from agricultural areas on Chimacum Creek passed the fecal coliform standard for "Class AA waters" - a very high water quality standard.
 
 

REGIONAL SALMON DATA

Long time residents of Chimacum Creek estimate that a 90% reduction has occurred in the creek's historic salmonid abundance (Bahls and Rubin 1996). In contrast,  the Washington Department of Fish and Wildlife and Western Wasnington Treaty Indian Tribes 1992 Washington State Salmon and Steelhead Stock Inventory defined the coho stock as "healthy" stock (WDF et al. 1993).  This "healthy" determination is based upon coho use of existing habitat and consistent runs over time. It does not take into consideration the compromised status of these habitats. With the exception of 1979 and 1980, coho stock in Chimacum creek have been consistently low. Likewise, between 1974 and 1992 the creek's run of summer chum declined:  1974 - 60 fish  counted per mile, 1983 - 3.5 fish counter per mile, 1992 - run extirpation (Lichatowich 1993). Looking at the neighboring summer chum runs in Hood Canal, we see similar declines in population and a corresponding increases in exploitation (NMFS 1997). These figures likely reflect some of the multiple cumulative factors in addition to spawning habitat degradation that have seriously impacted Chimacum's chum run. It is believed that strong ground water flows off the Olympic Mountains counter the rainshadow effect and provide adequate flows to support summer chum.

CHIMACUM RESTORATION COMMUNITY PARTNERSHIPS

In response to the decline and extirpation of summer chum, a strategic and cooperative effort on the part of S'Klallam Indian Tribes, state resource agencies, Chimacum High School, Jefferson County Conservation District (JCCD) was spearheaded by Wild Olympic Salmon (WOS), a non-profit group whose mission is to "inspire sustainable human community and culture by nurturing wild salmon and watersheds", was undertaken to reintroduce summer chum stock using neighboring broodstock from Snow Creek. The first returns from that effort are expected in late summer or early fall of 1999.

Wild Olympic Salmon and the Jefferson County Conservation District have also successfully completed a number of watershed restoration projects that include: widening channels to increase stream area, adding large woody debris to add stream complexity and variety of habitat, increasing vegetation to enhance the integration of terrestrial and aquatic ecosystems that over time will stabilize streambanks, absorb nutrient loads, and provide shade and woody debris. As the property along the creek is privately owned, these efforts have been opportunistic in nature (i.e. doing it when you can and where you can). As a land conservation organization, the Jefferson Land Trust (JLT) has also joined these community efforts to promote conservation in the watershed through acquisition of targeted conservation easements at strategic points along the watershed.

EFFORTS
#1) PROTECT REMAINING HABITAT
Targeting easement acquisition
#2) RESTORE LOST HABITAT
Jefferson County Conservation District and Wild Olympic Salmon have undertaken a number of efforts to restore the quality and quantity of salmonid habitat. The Conservation District works cooperatively with landowners to encourage natural resource conservation. Wild Olympic Salmon works to foster community understanding and stewardship of salmon and salmon habitat through restoration projects and public education programs in eastern Jefferson County. Working cooperatively, these groups have successfully restored and increased habitat. They have re-meandered portions of the stream, adding habitat area and complexity. They have reduced degrading impacts by fencing off livestock, adding vegetation and removing invasive reed canary grass. They have also removed sediment and attempted to enhance eelgrass habitat in the estuary in preparation for the return of their summer chum reintroduction effort.

MONITORING

This stream restoration and salmon recovery partnership that combines the elements of land and stream stewardship, landowner technical and financial assistance, public education and involvement, conservation easement acquisition and salmon recovery contains the elements essential to building a consistent stream and restoration monitoring system into perpetuity. Jefferson Land Trust acquisition of conservation easements of strategic habitats along the creek include headwaters, mainstem wetlands, lower mainstem and the creek's estuarine mouth. As the land trust performs its baseline easement monitoring obligations, the groundwork is laid for the development of a streamside monitoring system to target, prioritize and integrate restoration and conservation efforts on the part of JCCD, WOS and JLT. It provides the  opportunity to develop a monitoring and database system forbuilding consistent stream and bankside profiles into perpetuity.The following chart outlines the pieces that lay the necessary groundwork for a monitoring system.

Building a monitoring plan for targeted streamside acquisitions

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