PACIFIC LAMPREY (Lampetra tridentatus) PASSAGE AT ROCKY REACH ON THE MID-

Final

ROCKY REACH HYDROELECTRIC PROJECT FERC Project No. 2145

March 30, 2006

Prepared by: Golder Associates Castlegar, BC

Prepared for: Public Utility District No. 1 of Chelan County Wenatchee,

Pacific Lamprey Passage at Rocky Reach Dam on the Mid-Columbia River

TABLE OF CONTENTS

EXECUTIVE SUMMARY...... 1

SECTION 1: INTRODUCTION ...... 2

SECTION 2: APPROACH ...... 2

SECTION 3: ISSUES ...... 3 3.1 Adult ...... 3 3.2 Juvenile ...... 4

SECTION 4: OPPORTUNITIES ...... 6 4.1 Adults...... 6 4.2 Juveniles...... 8

SECTION 5: SUMMARY ...... 10

SECTION 6: REFERENCES ...... 10

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LIST OF TABLES

Table 1: Water Velocities at Various Points at Rocky Reach Dam (information provided by Lowell Rainey, Chelan PUD) ...... 5

LIST OF FIGURES

Figure 1: Inclined trap to Improve Adult Pacific Lamprey Passage at ...... 9

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EXECUTIVE SUMMARY

Little information exists on Pacific lamprey (Lampetra tridentatus) in the mid-Columbia River basin. The Chelan County Public Utility District No. 1 is investigating how its Rocky Reach Project may be affecting the movements of adult and juvenile lamprey. Interviews with federal, state, tribal and hydropower organizations were undertaken to gather information on lamprey passage issues and possible solutions at downstream on the Columbia River. The biological characteristics of adult lamprey, i.e., poor swimmers that avoid light and travel along the bottom, are central to understanding how the physical configuration and operational practices at dams affect passage success. Fewer problems are known for downstream migrating juvenile lamprey, especially because they can pass through turbines with not many problems. A variety of “low tech” and relatively inexpensive solutions to improving upstream adult passage are being investigated at a number of Columbia River dams. All of these different approaches have been conceived on the basis of a thorough understanding of lamprey biology. There are few opportunities available for improving passage of juvenile lamprey, however, this is likely of low significance. A telemetry study documenting how lamprey move past the Rocky Reach Project should allow dam operators to target specific areas for modification or retrofitting.

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SECTION 1: INTRODUCTION

A recent review (Golder 2003) of the status of Pacific lamprey (Lampetra tridentatus) in the Rocky Reach Reservoir system found there is practically no information in the mid-Columbia River area regarding this potentially threatened species. The challenge facing the Chelan County Public Utility District (Chelan PUD) is to understand how their dam and its operations may potentially affect Pacific lamprey. With this knowledge, it may be possible to institute physical changes and/or operational practices to address potential project-related impacts.

SECTION 2: APPROACH

At present, there are various efforts underway in the Columbia River Basin downstream of to collect basic information on lamprey biology, population status and passage issues associated with dams. These initiatives are being delivered by a range of federal, state, tribal and hydropower organizations. Of relevance to the Chelan PUD and Rocky Reach Dam is the work being directed at understanding adult upstream and juvenile downstream passage at lower Columbia River projects.

To better understand these research projects, a series of interviews (in-person and by telephone) were conducted with the primary investigators and their respective staff. These interviews were unstructured and intended to collect as much information as possible in order to outline a series of possible operational alternatives and physical modifications for the Rocky Reach Project. The biological staff interviewed were:

Mary Moser, Northwest Fisheries Science Center, Seattle, WA Russ Moursund, Laboratory, Richland, WA Lowell Rainey, Chelan County PUD, Wenatchee, WA Thad Mosey, Chelan County PUD, Wenatchee, WA Kenneth Hamm, Pacific Northwest Laboratory, Richland, WA Dan Domina, Portland General Electric, Estacada, OR Richard Beamish, Fisheries and Oceans Canada, Nanaimo, B.C. Chris Peery, University of Idaho, Moscow, ID Tammy Mackay, BPA, Bonneville Dam, WA

In addition to these contacts, the Golder author attended a one-day workshop held by the Columbia River Basin Lamprey Technical Workgroup in Vancouver, WA, on March 8, 2004.

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SECTION 3: ISSUES

There are a variety of issues associated with lamprey passage at dams which may be relevant to the Rocky Reach Project.

3.1 Adult

3.1.1 Swimming Ability/Biology Adult Pacific lamprey on their upstream spawning migration typically enter the Columbia River during the spring and early summer months (Moser et al. 2003). Those stocks which will move long distances upstream, e.g., those that move past the Rocky Reach Project, will overwinter in the river then complete their spawning migration into tributary systems the following spring (Beamish 1980). During the upstream spawning migration, lamprey do not feed and as a consequence, undergo a reduction in length (and weight) in the order of 20% compared to when they entered the river (Beamish 1980). Those fish migrating further up in their respective systems would likely undergo even greater length and weight losses.

Although lamprey can ascend steep sections of river and migrate long distances, they do have difficulties when they encounter high velocity areas and turbulent waters, such as at falls and man- made dams. In situations such as these, the lamprey will attach themselves to rocks or other surfaces using the strong suction pressure generated within their oral disk. They will then advance using a repeated lunge-and-attach motion. In this manner, larger lamprey have been known to ascend very steep areas as well as wall-faces within different structures of dams (Mary Moser, pers. comm., 2004).

3.1.2 Ambient Light Conditions Lamprey are generally known to be negatively phototactic and as a consequence, migrate along or close to the river bottom. Research by Daigle et al. (2004, draft) reports that adult lamprey in a variety of controlled experiments at the Bonneville Dam maintained this behavior once they entered the fishways. The lamprey in their experiments preferred to travel at night and stayed on or close to the bottom of fishways.

3.1.3 Attraction to Fishways Lamprey, by virtue of their ability to slip through narrow openings and ascend near-vertical surfaces, are able to pass substantial in-river blockages. At present there is much uncertainty about what conditions are cued on by lamprey as attraction features to a fishway (Daigle et al. 2004, in draft). This is important because not knowing what attracts a lamprey to a certain part/entrance of a dam renders the decision about physical modifications difficult, both operationally and financially.

3.1.4 Physical Configurations By necessity and conventional construction practices, dams possess numerous physical features which have the potential to impede, delay and, in a worst-case-scenario, block upstream lamprey passage. The ability to attach to a suitable surface and withstand swift water then is essential to a lamprey’s ability to surpass these types of obstacles. At the Rocky Reach Project there are specific

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key areas of the physical structure that may represent potential barriers to this mode of upstream migration: • 90° corners on bulkhead walls or orifice opening walls where fish are unable to release their hold, lunge forward and reestablish their grip before being swept downstream, e.g., in the fishway, entrances to the Left Powerhouse Entrance (LPE), orifice openings in the fishway.

• Areas where bottom grates are installed. In these areas, e.g., fishway, collection channel, and transport channel, the adult fish, if they swim along the bottom (preferred location), are not able to develop the necessary suction with their oral disk in order to attach themselves and maintain their position in areas of high water velocity.

• Gate slots at the various powerhouse entrances are configured with tracks in order to permit the installation of stop logs as operational requirements dictate. These tracks are essential to proper gate functioning, however, they and the attendant fast water moving past them, provide an unusual feature where lamprey likely have difficulties attaching and swimming past.

3.1.5 Water Velocities Water velocities measured at various points within the Rocky Reach Project are summarized in Table 1. Velocities and turbulence at the various entrances to the fishway may represent challenges to successful passage into the actual fishway. Areas where there are significant velocity differentials, e.g., orifice openings, gate wells, etc., are difficult for an adult lamprey to surpass. Turbulent water also presents problems for lamprey attempting to enter a fishway.

3.2 Juvenile

3.2.1 Macropthalmia and Ammocoetes Larval Pacific lamprey (ammocoetes) spend anywhere from 4 to 7 years burrowing in soft sediments of tributary streams and larger rivers. Their physical attributes (incomplete oral hood, lack of eyes) dictate that they face upstream into the current to filter-feed on algal material (primarily diatoms) with only their oral hood extending beyond the substrate. They regularly emerge from their burrows and undergo a passive downstream movement until they burrow into a new area of soft substrate. Eventually the ammocoetes undergo a transformation into macropthalmia where they develop large eyes, properly formed teeth, a counter-shading coloration, as well as physiological changes that prepare the animal for a marine existence during its adult phase. In a stream system there is a general tendency to see larger ammocoetes and macropthalmia distributed more frequently toward the lower reaches. A distinction must be made regarding these two life phases: whereas the macropthalmia are migrating downriver toward the ocean as part of their ordinary life cycle, the ammocoetes are merely continuing their passive downstream displacement, i.e., they are not migrating per se.

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Table 1: Water Velocities at Various Points at Rocky Reach Dam (information provided by Lowell Rainey, Chelan PUD)

Site Name Velocity (ft/s) Right Powerhouse Entrance -1 4.8 Right Powerhouse Entrance (2 m upstream) 2.6 G21 3.6 G18 2.6 G15 3.1 G12 2.5 G9 2.8 G6 1.85 G4 1.75 Wing Gate-1-U/S (Type D) 1.3 Wing Gate-1-D/S-a (Type D) 1.5 Wing Gate-1-D/S-b (Type D) 3 Left Powerhouse Entrance 7.8 Wing Gate-2 (Type B) 1 Wing Gate-3 (Type C) 2.2 C3 2 C1 1.7 Transportation Channel 1.6 Fishway Control Room 1.6 A1 2.5 Counting Station 4.5 Main Spillway Entrance- U/S 1.8 Main Spillway Entrance- D/S 7.4

There is a seasonality to juvenile downstream migration that is tied with spring freshet. In general, the greatest number of macropthalmia, and ammocoetes, caught in traps fished throughout the year are caught during the freshet period. This is what would be expected given that juvenile lamprey are poor swimmers and have to rely on higher and faster water to move them downstream to the estuary. The large number of ammocoetes traveling at this time of year likely reflect scouring and redistribution of the sandy-silty substrates, their preferred habitats.

3.2.2 Migration Behavior Juvenile lamprey (macropthalmia and ammocoetes), like adult lamprey, stay close to the stream or river bottom during their active and passive migration periods. Also like adults, they prefer low light conditions and travel mostly during the night (Moursund et al. 2003).

3.2.3 Screens Many dams on the Columbia River have submerged-bar screens on their intakes. These screens are intended to redirect downstream migrating salmonid smolts into a fish bypass system. The openings on these wedge-wire screens (typically 1/8th inch {3.2 mm}) represent no threat to salmonid smolts owing to their relatively large size. For juvenile lamprey however, given their thin tails and poor swimming ability, these wires can become a trap (Russell Moursund, pers. comm., 2004). The problem is accentuated by the whip-like tail movements of these fish as they attempt to extract

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themselves from between the wires if they become caught tail first. At the Rocky Reach Dam, these screens do not extend much below the surface and consequently, given the tendency of lamprey to migrate along the bottom, likely do not represent a threat to young lamprey.

3.2.4 Turbine Passage The lamprey’s physical structure plays a significant role in its ability to withstand high shear stress and abrupt pressure changes. The lack of a swim bladder is fundamental in explaining their high survival rates in experimental tests where they are exposed to rapid changes in pressure (Moursund et al. 2003). The absence of certain structures, e.g., bony skeleton, large eyes, operculum, that salmonids possess is likely the reason that they are not injured at the rates of strain known to injure and kill salmonids (Moursund et al. 2003). There is presently no information on potential injuries to juvenile lampreys from striking the turbine blades, nor does information exist suggesting one turbine type is more efficient at passing lamprey with less damage than another type (Moursund et al. 2003).

SECTION 4: OPPORTUNITIES

4.1 Adults There are presently a number of studies underway at the Bonneville Dam attempting to document the benefits to adult lamprey passage as a consequence of modifying physical structures.

4.1.1 Ramp Research being conducted at the Bonneville Dam (Mary Moser, pers. comm., 2004) is investigating movement of adult lamprey up an inclined trap; results to date are promising. A schematic of the inclined trap is presented in Figure 1. In essence, the trap has undergone a number of alterations and variations in an attempt to produce a prototype that has the ability to pass lamprey up a very steep surface to a trap where they can be physically removed and transported upstream to the forebay. Her present research is looking for ways to eliminate the human intervention and have the lamprey move directly from the fishway into a series of structures and up into the forebay. Regardless of the success of this most recent effort, the work demonstrates the lampreys’ well- known ability to move up steep surfaces with a minimal amount of water. Such a scenario may be applicable at Rocky Reach should future research, i.e., telemetry studies, demonstrate that there are upstream passage “hot spots” once lamprey move into the fish ladder.

4.1.2 Fishway Bottom Owing to the physical shape of an adult’s mouth, and its mechanism of advancing in the face of relatively high water velocities (lunge-and-grab), lamprey need a proper attachment surface where they can hold, rest and lunge from. The gratings in the floor of the fish ladder, and collection and transport channels at the Rocky Reach Project likely do not allow lamprey to attach themselves. Given their preference for moving along the bottom of stream channels and avoiding light, this means the only place they can attach is the walls of these structures; it is not known whether they do this at the Rocky Reach Project.

Mary Moser (pers.comm., 2004) and Chris Peery (pers.comm., 2004) have experimented with a variety of bottom types and generally found improved passage as a consequence of these

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modifications. The placing of plating over a portion of the grating allows a firm surface for attachment for lamprey and in experimental scenarios has improved passage. Furthermore, work by Daigle et al. (2004, in draft) demonstrated that the addition of artificial rocks on the floor of the fishway decreased the amount of time fish took to pass through an orifice at Bonneville Dam and increased the proportion of fish which made use of the orifice. These two relatively simple retrofittings may have direct applicability to the Rocky Reach fishway.

4.1.3 Rounded Bulkhead Wall Ends Owing to the lamprey’s mode of upstream migration (attach-and-lunge), and the difficulties associated with surpassing areas of high velocity, experimental retrofits have been undertaken at the Bonneville Dam. These retrofits consist of attaching half-pipes to various 90° corners in the fishway system. Initial indications (supported by video footage) indicate that even in the face of very high water velocities, the lamprey can swim past because of their ability to firmly attach to a solid surface. Discussions with the on-site biologist (Tommy Mackay, pers. comm., 2004) have determined that this low-tech retrofit is fairly inexpensive and does not require specialized materials. A potential challenge at the Rocky Reach Project (and likely other dams) is the notched gatewell tracks. These areas represent particular problems since by definition they are “corners” that can’t be rounded out. Preliminary discussions with Lowell Rainey (pers. comm., 2004) have resulted in a number of possible solutions, e.g., rubber fillers that fill the notched gatewell track. Such an approach may provide a solid surface for lamprey attachment, although a more detailed investigation on physical structures and dimensions is necessary.

4.1.4 Maintenance Practices As discussed, lamprey migrating long distances up the Columbia River system enter fresh water in the spring and overwinter until the following spring when they complete their migration, spawn and die. During the winter period, the Chelan PUD undertakes its annual maintenance activities in the fishway. Special attention should be taken to reduce the ramping rate in an attempt to naturally flush any lamprey holding in the fishway out before the maintenance starts. If adult fish are encountered, they should be collected by net, transported to the forebay and released. This practice would minimize stress or damage that may occur to holding lamprey should they choose to stay in the fishway and not back down.

4.1.5 Orifice Openings The Rocky Reach Project has 22 orifice entrances to the collection channel. The number open, configuration and actual openings of these gates are controlled by the Fishway Operator (Lowell Rainey, pers. comm., 2004). At present, there are no site-specific data on water velocities at different orifices or different orifice openings. Research by Daigle et al. (2004) has confirmed that lamprey move along the bottom during their upstream passage. When they encounter a “step” they must swim up and into a zone of large current differential; they are typically swept away (Mary Moser, pers. comm., 2004). This area of current differential represents the most significant obstacle to lamprey movement, especially when there is no firm surface amenable to lamprey attachment. Any orifice gate that results in a zone of significant current differential will potentially represent a barrier to effective and efficient lamprey passage. By manipulating orifice openings and experimenting with the number and arrangement of closed and opened orifices to the collection channel, it may be possible to provide easier access to the fishway.

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4.1.6 Powerhouse Entrance/Spillway Gate Openings The gate openings at the two powerhouse entrances and main spillway entrance result in very high exit velocities. By necessity, these openings are gated in order to control the volume of water that they pass. The Right Powerhouse Entrance (RPE) is an area with exceptionally high exit-water velocities that likely cannot be ameliorated. At the LPE however, it may be possible, by a combination of gate openings (there are three gates at the LPE) to reduce water velocities so that, acting in combination with some retrofitting of rounded corners, lamprey can navigate their way into the collection channel.

4.2 Juveniles Information provided by the Chelan County PUD indicates that the numbers of juvenile lamprey being impinged and trapped on the bar screens is low (Lowell Rainey, pers. comm., 2004). Caution must be exercised in reviewing this information owing to the manner in which it was collected, i.e., incidentally, and to the lack of specific information as to the stage of the lamprey, i.e., ammocoetes versus macropthalmia.

4.2.1 Behavioral Avoidance Owing to their preference for migrating during periods of low light, it may be possible to use artificial light at the surface of the water to “force” any downstream migrating/moving lampreys lower down in the water column thereby avoiding impingement and subsequent trapping on the upstream facing sides of the screens. At the Rocky Reach Project, such a technique would have to be evaluated with regard to possible effects on downstream migrating smolts, e.g., smolts may also avoid the light and sound, thereby missing the surface collector system.

4.2.2 Screens The submerged bar screens on Units 1 and 2 function to screen plant material and fish from entering their intakes. During real-time monitoring (via camera) of intake screen cleaning and a review of weekly screen cleaning videos, two lamprey macropthalmia were observed to have been impinged on the screens from 18 April to 19 August, 2003. The videos represent approximately 20% of the total area of submerged bar screens at Rocky Reach. Due to the low occurrence of lamprey impingement, any potential management options are unlikely to have a significant impact on downstream moving juvenile lamprey.

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Figure 1: Inclined trap to Improve Adult Pacific Lamprey Passage at Bonneville Dam

(Mary Moser, pers. comm.)

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SECTION 5: SUMMARY

Pacific lamprey movement past the Rocky Reach Dam is an area of interest to regulatory and tribal agencies. Adult lamprey moving upstream past the dam potentially encounter a variety of obstacles as a consequence of their biology, i.e., swimming ability and physical morphometry, as well as dam structures/features, e.g., grates on the fishway channel, high water velocities at the powerhouse entrances, etc. Other potential challenges exist for downstream migrating/moving macropthalmia and ammocoetes. The problems for both adults and juveniles may be exacerbated by dam operations and physical modifications for downstream migrating salmonid smolts, e.g., surface collector system, and upstream migrating salmon/trout, e.g., lights in the collector tunnel. Numerous opportunities exist to improve upstream passage of adult lamprey. Many of these involve methods that are relatively “low tech”, and could be carried out with a minimum of engineering and at low cost. There are fewer opportunities to address potential passage issues with juvenile lamprey, although given their high survival during turbine passage this may not be a significant issue. The first step should be to complete an adult telemetry study to identify specific features of the dam that potentially represent adult migration obstacles. The next step would be to determine the feasibility of modifying any obstacles that are identified. First-hand knowledge of the actual modifications at other dams, e.g., Bonneville and McNary, would be beneficial in making this evaluation. In the absence of site specific information about whether there are passage difficulties being caused by specific aspects/operations of the dam, a risk analysis of benefits versus cost, including due consideration to the salmon and steelhead which pass this dam, should be conducted.

SECTION 6: REFERENCES

Bayer, J. and J. Seelye. Undated abstract. Upstream migration of Pacific lamprey (Lampetra tridentat) in the Columbia River. U.S. Geological Survey, Biological Resources Division, Cook, WA.

Beamish, R.J. 1980. Adult biology of the river lamprey (Lampetra ayersi) and Pacific lamprey (Lampetra tridentata) from the Pacific Coast of Canada. Canadian Journal of Fisheries and Aquatic Science. 37:1906-1923.

Daigle, W.R., C.A. Peery, S.R. Lee, and M. Moser. 2004. Evaluation of adult Pacific lamprey passage, swimming performance, and behavior in an experimental fishway at Bonneville Dam. Draft Report for: U.S. Army Corps of Engineers, Portland, Oregon. 46 pp.

Golder Associates Ltd. 2003. Review of Pacific lamprey in the Rocky Reach Project area. Prepared for: Chelan County Public Utility District No. 1., Wenatchee, Washington.

Mackay, Tammy. 2004. Personal Communication. Bonneville Power Authority, Bonneville Dam, Washington.

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Moser, Mary. 2004. Personal Communication. Northwest Fisheries Science Center, National Marine Fisheries Service, Seattle, Washington.

Moser, M.L., D.A. Ogden, S.G. McCarthy, and T.C. Bjornn. 2003. Migration behavior of adult Pacific lamprey in the lower Columbia River, and evaluation of Bonneville Dam modifications to improve passage, 2001. Report for: Portland District, U.S. Army Corps of Engineers, Portland, Oregon. Contract E96950021. 50 pp.

Moursund, Russell. 2004. Personal Communication. Pacific Northwest National Laboratory, Richland, Washington.

Moursund, R.A., M.D. Bleich, K.D. Hamm, and R.P. Mueller. 2003. Evaluation of the effects of extended length submerged bar screens on migrating juvenile Pacific lamprey (Lampetra tridentata) at in 2002. Final Report prepared for: U.S. Army Corps of Engineers, Portland, Oregon. Contract DE-AC06-76RL01830.

Rainey, Lowell. 2004. Personal Communication. Chelan County Public Utility District No. 1, Wenatchee, Washington.

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