Monitoring Program Terms of Reference REVELSTOKE FLOW MANAGEMENT PLAN

Transcription

1 Columbia River Project Water Use Plan Monitoring Program Terms of Reference REVELSTOKE FLOW MANAGEMENT PLAN CLBMON-18 Middle Columbia River Adult Fish Habitat Use Revisions May 12, 2010

2 Revised Terms of Reference for the Columbia River Project Water Use Plan Monitoring Programs Revelstoke Flow Management Plan 1.0 OVERVIEW This document presents Terms of Reference for the effectiveness monitoring programs for the Revelstoke Flow Management Plan (RFMP, Table 1). These programs will monitor outcomes of the recommended operational changes, and provide information on which to base future operating decisions. This document provides detailed Terms of Reference for the following programs: 1) CLBMON-15a & b Middle Columbia River Physical Habitat and Ecological Productivity Monitoring: A 13-year program to monitor physical habitat parameters, periphyton, and benthic invertebrates in the Middle Columbia River to determine linkages between operational changes, physical habitat, and ecological productivity. 2) CLBMON-16 Middle Columbia River Fish Population Indexing Surveys: A 13-year program to monitor abundance and biological characteristics of fish populations in the Middle Columbia River to assess the response of these populations to operational changes at Revelstoke Dam. 3) CLBMON-17 Middle Columbia River Juvenile Fish Habitat Use: A 6-year program to monitor changes in habitat use by juvenile fishes in the Middle Columbia River in response to operational changes at Revelstoke Dam. 4) CLBMON-18 Middle Columbia River Adult Fish Habitat Use: A 6-year program to monitor behavioural (diel and seasonal) and energetic responses of selected adult fish species (bull trout and mountain whitefish) to operational changes at Revelstoke Dam. Table 1 Revelstoke Flow Management Plan Monitoring Program Terms of Reference Resubmission Information Name of Monitoring Program CLBMON-15a Middle Columbia River Physical Habitat Monitoring CLBMON-15b Middle Columbia River Ecological Productivity Monitoring CLBMON-16 Middle Columbia River Fish Population Indexing Surveys CLBMON-17 Middle Columbia River Juvenile Fish Habitat Use CLBMON-18 Middle Columbia River Adult Fish Habitat Use CLBMON-53 Middle Columbia River Juvenile Fish Stranding Assessment Order Clause Fulfilled Schedule C: 4.a Schedule C: 4.a Schedule C: 4.b Schedule C: 4.c Schedule C: 4.d Amended Order, Clause 2 (c) Submitted with this Package Previously Submitted To CWR Submission Dates March 2007, January 2009 March 2007, January 2009 March 2007, January 2009 March 2007 March 2007 No July 2008, February 2009 BC Hydro Page 2

3 The monitoring program will be implemented over a 13-year time span, which exceeds the study duration recommended by the Water Use Plan Consultative Committee by one year. The increased duration is to honour BC Hydro s commitment to the Revelstoke 5 (REV 5) Core Committee to advance implementation of three studies (CLBMON-15a, 15b and 16) to allow for an extra year of baseline data collection. One year was also added to the end of CLBMON-17 and 18, extending them to six year studies from the original five. CLBMON-53 was added to the Order as a result of the REV 5 WUP amendment. 2.0 MONITORING PROGRAM RATIONALE The Columbia River Water Use Plan Consultative Committee (WUP CC) identified the potential impacts of the operation of Arrow Lakes Reservoir (ALR) and Revelstoke Dam on large river fish habitat in the Middle Columbia River as a key environmental concern of the Columbia River Water Use Plan. The quality and quantity of large river habitats in the Middle Columbia are thought to be heavily influenced by the operation of Arrow Lakes Reservoir and flow releases from Revelstoke Dam. The length of flowing river in the Middle Columbia is controlled by the seasonal operating elevation of Arrow Lakes Reservoir (Figure 1). The Arrow Lakes Reservoir normally fills from April to July, inundating the ~50 km length of Middle Columbia River channel and floodplain. At full pool (440 m), ALR backwatering influences the Middle Columbia River as far as the base of Revelstoke Dam. Maximum reservoir elevation and the duration at which it is maintained vary annually based on a complex combination of climate, treaty obligations, and operational needs. Short-term variations in Revelstoke Dam flow releases (including zero discharge events) are thought to influence the quality of fish habitats in the Middle Columbia River. Load following and peaking operations have resulted in patterns of river discharge that vary on a diel, seasonal, and annual basis, with discharges ranging from 0 to 1700 m 3 s -1. Flow releases from Revelstoke Dam generally increase through daylight hours and peak in early evening following peak demands for power. During night time periods, however, generating station output is typically reduced to follow electricity demand and flow releases from Revelstoke Dam frequently cease completely depending the time of year. Periods of zero discharge, which occur mainly during spring (March to May) and fall (September to November), could limit the availability and suitability of large river habitats for fishes. The WUP CC recommended establishment of a year round 142 m 3 s -1 minimum flow release from Revelstoke Dam to enhance large river fish habitats in the Middle Columbia River. Key environmental objectives of the minimum flow release are to: 1) increase productivity of benthic communities, 2) develop habitat conditions that increase the recruitment of juvenile fishes, and 3) maximize the abundance, condition, and growth of adult fishes. In developing the minimum flow recommendation for Revelstoke Dam, it was recognized that there was considerable uncertainty about the environmental benefits of the proposed minimum flow release. This uncertainty was attributed to significant data gaps about the current status of aquatic communities in the Middle Columbia River, and the lack of data on the importance of mainstem large river habitats relative to reservoir and adjacent tributary habitats available to fishes in the Upper Arrow watershed. To help resolve these data gaps, reduce technical uncertainties and assess the effectiveness of the 142 m 3 s -1 minimum flow, the WUP CC recommended an adaptive management program, collectively referred to as the Revelstoke Flow Management Plan (RFMP). BC Hydro Page 3

4 BC Hydro received approval for the construction of a fifth unit (REV 5) at the Revelstoke Generating Station in REV 5 will add 500 MW to the station s generating capacity and its operation will allow for peak discharge of 2124 m 3 s -1, an additional 425 m 3 s -1 over current operations. The in-service date for full operation of REV 5 has been scheduled to coincide with the start of the recommended minimum flow in November Some of the predicted trends with REV 5 operations include: a general increase in the frequency of high flows with corresponding increases in river elevations and velocities immediately downstream of the dam and a general increase in average daily discharge during low demand periods (BC Hydro 2006). BC Hydro received an amended Order that includes recommendations from the REV 5 process for additional monitoring programs and physical works. Some of these changes are included in the individual study Terms of Reference for the RFMP. The RFMP is a 13-year program to monitor the effectiveness of the minimum flow release as recommended by the WUP CC (Tables 1 and 2). The approach of the program is to estimate the responses of key physical and biological variables to operations. These responses will then be interpreted to assess the effects of minimum flow and REV 5 operations on benthic and fish productivities of the Middle Columbia River ecosystem. In the first four years of the program ( ), operation of the dam will not change and monitoring will be conducted to supplement existing data on physical and biological conditions of the Middle Columbia ecosystem under the current operating regime. Operational changes such as the implementation of the minimum flow and full in-service operation of REV 5 will be timed to coincide in late Monitoring programs will continue for a range of three to 10 additional years, depending on specific information requirements. An interim review of the Revelstoke Flow Management Plan (Table 2) will provide an opportunity to examine initial results and, where required, refine the monitoring program to better meet key objectives. To structure these assessments, a simple conceptual diagram was developed to describe how physical factors could influence fish populations in the Middle Columbia River (Figure 2, see also BC Hydro 2005). This diagram outlines linkages among factors that substantially influence physical habitat conditions in the Middle Columbia River (e.g., dam releases, tributary inflows, reservoir operations) and the responses of benthic communities and fish populations. Five integrated monitoring programs were recommended to address key data requirements and uncertainties articulated in the conceptual model regarding impacts of minimum flow releases on the Middle Columbia River ecosystem (BC Hydro 2005). Four programs relate to habitat (CLBMON-15a Physical Habitat Monitoring), benthic community (CLBMON-15b Ecological Productivity) and fish population indicators (CLBMON-16 Fish Population Indexing Surveys and CLBMON-17 Juvenile Habitat Use). An additional monitoring study was recommended to provide a greater understanding of the behavioural and bio-energetic consequences of operations on fish habitat use (CLBMON-18 Adult Habitat Use). This study focuses on specific biological uncertainties associated with the prescribed minimum flow and seeks to answer the following questions: 1) what is the behavioural response (diel and seasonal pattern of habitat use) of adult fishes to minimum flows? and 2) do minimum flows generate bio-energetic benefits (and therefore potential for increased growth) for individual fishes? To integrate the elements of the monitoring program and coordinate the analyses of monitoring data, all programs will be implemented on a common spatial referencing approach (Figure 1). Establishment of a common spatial stratification scheme will facilitate linking key hypotheses, as they relate to the response of ecological indicators to changes in minimum flow releases and REV 5 operations through a logical chain of inference (e.g., physical habitat benthic productivity fish habitat use fish productivity). It will also facilitate documentation of the BC Hydro Page 4

5 influence of Revelstoke Dam releases, tributary inflows/contributions, and Arrow Lakes Reservoir operation on physical and biological components of the ecosystem. The geographic scope of the RFMP is the Middle Columbia River section extending ~30 km from the Akolkolex River to the tailrace of Revelstoke Dam (Reaches 2, 3 and 4; Figure 1). However most programs (with the exception of CLBMON 15a) will prioritize the upper two reaches (3 and 4), which are the portion of the Middle Columbia River most influenced by operational changes. 3.0 REFERENCES BC Hydro Revelstoke Unit 5 Project Environmental Assessment Certificate Application. Volume 1: Supplemental Information Report. BC Hydro Consultative Committee Report: Columbia River Water Use Plan, Volumes 1 and 2. Report prepared for the Columbia River Water Use Plan Consultative Committee by BC Hydro, Burnaby, BC. BC Hydro Page 5

6 Reach 3 Reach 4 Reach 2 Reach 1 Figure 1 Map of the study area for the Revelstoke Flow Management Plan showing the location of the Revelstoke Dam and reach breaks used in the RFMP. BC Hydro Page 6

7 Dam flow release Tributary Inflow Reservoir Elevation Flow Velocity Wetted Area Inundation Frequency Physical Habitat Monitoring Juvenile Habitat Use Adult Habitat Use Benthic productivity Ecological Productivity Monitoring Useable area Energy expenditure Food supply Fish Growth Fish survival Fish abundance Fish Population Indexing Monitoring Figure 2 Conceptual diagram of linkages among physical and biological variables responding to Revelstoke Dam flow releases and Arrow Lakes Reservoir operations on large river habitats in the Middle Columbia River. Associated monitoring programs proposed in the Revelstoke Flow Management Plan are shown in italics. BC Hydro Page 7

8 Addendum #1 May 20, 2010: Middle Columbia River Adult Fish Habitat Use (CLBMON-18) 1.0 MONITORING PROGRAM RATIONALE 1.1 Background The Columbia River Water Use Plan Consultative Committee (WUP CC) supported the implementation of a year-round minimum flow release of 142 m 3 s -1 from Revelstoke Dam to enhance fish populations of the Middle Columbia River (BC Hydro 2005a, 2005b). A key uncertainty related to the minimum flow release, as expressed by the WUP CC, was how the implementation would affect and/or benefit fish populations that use the Middle Columbia River. This monitoring program will document the pattern of habitat use and daily activity of some fishes that use large river habitats in the Middle Columbia River and how they are influenced by flow releases. In 2007, BC Hydro received approval for the construction of a fifth unit (REV 5) at the Revelstoke Generating Station. REV 5 will add 500 MW to the station s generating capacity and its operation will allow for peak discharge of 2124 m 3 s -1, an additional 425 m 3 s -1 over current operations. The in service date for full operation of REV 5 has been scheduled to coincide with the start of the minimum flow in November Some of the predicted trends with REV 5 operations include: a general increase in the frequency of high flows with corresponding increases in river elevations and velocities immediately downstream of the dam and a general increase in average daily discharge during low demand periods (BC Hydro 2006). An addendum to the WUP includes the provision to include monitoring of REV 5 operations in these Terms of Reference. Therefore, references to evaluating the minimum flow releases or operational changes should be interpreted as including REV 5 operations. 1.2 Management Questions The key management questions addressed by this monitoring program are: 1) What are the movement patterns of selected resident fish species in the Middle Columbia River? 2) How do fishes in the Middle Columbia respond to diel variations in flow from Revelstoke Dam? 3) Does the implementation of the 142 m 3 s -1 minimum flow affect the energy expenditure of resident fishes from the Middle Columbia, and does this affect their growth or survival? Understanding the interactions between timing of fish movements and availability of suitable large river habitat will help to infer how implementation of a minimum flow may influence productivity of fish populations. Similarly, understanding the extent to which fish alter their diel patterns of habitat use in relation to flows from Revelstoke Dam will help to infer the benefits of the 142 m 3 s -1 minimum flow regime changes. 1.3 Management Hypotheses BC Hydro Page 8

9 Two primary hypotheses will be tested in this monitoring program: Ho 1 : The implementation of the 142 m 3 s -1 minimum flow release does not alter the pattern of movement of fishes in the Middle Columbia River. Ho 2 : The implementation of the 142 m 3 s -1 minimum flow release does not alter daily energy expenditures of fishes. 1.4 Key Water Use Decision Affected The key water use planning decision affected by the results of this monitoring program is the implementation of the 142 m 3 s -1 minimum flow release from Revelstoke Dam. This monitoring program seeks to assess how the provision of a minimum flow and REV 5 operations will affect diel and seasonal patterns of fish habitat use in the Middle Columbia River. Information derived from the program will be used to assess how minimum flows affect the quality of fish habitat in the Middle Columbia River. The results from this program will be integrated with the four other monitoring programs of the RFMP (Physical Habitat Monitoring, Ecological Productivity Monitoring, Fish Population Indexing Surveys, and Juvenile Habitat Use) and will be used to support inferences about benefits of the minimum flows for fish. Results from the RFMP programs and associated inferences will be used to establish the long term operating release requirements for the Revelstoke Dam. 2.0 MONITORING PROGRAM PROPOSAL 2.1 Objectives and Scope The primary objectives of the Middle Columbia River Adult Habitat Use monitoring program are: 1) To provide detailed information on the patterns of residence and movements of selected fish species in the Middle Columbia River. 2) To provide detailed information on daily patterns of habitat use and activity of selected fishes in the Middle Columbia River in response to flow fluctuations. 3) To determine whether fishes vary their diel patterns of habitat use in response to the implementation of the 142 m 3 s -1 minimum flow release from Revelstoke Dam and operations of REV 5. The scope of the monitoring program is divided in two parts: 1) To design and implement a program to monitor patterns of movements and activity of two key species (bull trout and mountain whitefish) in relation to flow releases from Revelstoke Dam; and, 2) To determine if changes in fish spatial patterns of habitat use and daily patterns of activity are altered by the implementation of the minimum flow release and REV 5 operations. BC Hydro Page 9

10 The geographic scope of the monitoring program is the ~6 km long section of the Middle Columbia River from the Jordan River confluence to the Revelstoke Dam tailrace (Reach 4). Reach 3 (to the Illecillewaet River confluence) will be included as conditions allow. 2.2 Approach The approach of this program is to monitor the pattern of habitat use of two key fish species and to quantify their activity and metabolic energy expenditures in a section of the Middle Columbia River subject to regular changes in flow patterns. Electromyogram (EMG) radio telemetry will be used to quantify fish energy expenditures. The method entails the surgical insertion of probes into fish red muscles: these probes send records of bioelectric potentials, which are then correlated with muscle contractions strength and duration. These are in turn related to metabolic costs. This will involve tracking a representative sample of bull trout and mountain whitefish to describe their spatial movements and daily activity patterns in relation to flows. Activity patterns of these fishes will be monitored under the existing Revelstoke Dam flow regime, and for three years following the implementation of the 142 m 3 s -1 minimum flow release regime and operation of REV 5. The monitoring results will be used to test hypotheses about the effects of flows on fishes. 2.3 Methods The following tasks are required to complete adult habitat use monitoring in the Middle Columbia River: Task 1: Project Management Project coordination involves the general administrative and technical oversight of the program. This will include, but not be limited to: 1) budget management, 2) study team management, 3) logistic coordination, 4) technical oversight in field and analyses components, and 5) facilitation of data transfer among other investigators associated with the RFMP. A safety plan must be developed and submitted to the BC Hydro contact for all aspects of the study involving field work, in accordance with BCH procedures and guidelines. Specific safety training may be required Task 2: Fish Sampling Field studies will monitor annually the daily patterns of habitat use of bull trout and mountain whitefish in the Middle Columbia River study area. The main elements of the field program should include, but may not be limited to, strategic tracking and monitoring of fish locations and daily activity patterns in relation to flows using both EMG and locational telemetry. Efforts will be made to coordinate the capture and tagging of suitable individuals from the fish population indexing studies (CLBMON-16), as long as sampling methods do not affect behaviour and health of fish. EMG output will be calibrated to relevant physiological measures to assess energy expenditure. It is recommended that on-site tag calibration be undertaken to develop general species-specific functional relationships for translating EMG signal output to tail beat frequency, swim speed, and metabolic expenditures. BC Hydro Page 10

11 2.3.3 Task 3: Reporting An annual technical report will be completed for each year of the monitoring program. This report will document methods, results, conclusions, and recommendations as they pertain to the specific objectives of this monitoring program. To facilitate effective management of data from the monitoring program, an MS ACCESS data base will be developed and updated on an annual basis. At the completion of the monitoring period, a detailed report will be prepared to synthesize the data collected over the term of the program. Reports will follow the standard format that is being developed for WUP monitoring programs. All reports will be provided in hard copy and as Microsoft Word and Adobe Acrobat (*.pdf) format, and all maps and figures will be provided either as embedded objects in the Word file or as separate files. 2.4 Interpretation of Monitoring Program Results The results from this program will be integrated with the four other monitoring programs of the RFMP (Physical Habitat, Ecological Productivity, Fish Population Indexing Surveys, Juvenile Habitat Use) and will be used to support inferences about benefits of the minimum flow for fish and effects of REV 5 operation. Results from the RFMP programs and associated inferences will be used to establish the long term minimum operating requirements for the Revelstoke Dam. 2.5 Schedule The proposed duration for this monitoring program is six years, beginning three years prior to the implementation of operational changes. The first two years of the program (2008 & 2009) have already been completed. 2.6 Budget Total Program Cost: $820, REFERENCES BC Hydro Revelstoke Unit 5 Project Environmental Assessment Certificate Application. Volume 1: Supplemental Information Report. BC Hydro. 2005a. Consultative Committee report: Columbia River Water Use Plan, Volumes 1 and 2. Report prepared for the Columbia River Water Use Plan Consultative Committee by BC Hydro, Burnaby, BC. BC Hydro. 2005b. Columbia River Project, Draft Water Use Plan. 38 pp. + appendices BC Hydro Page 11