Prospect No. 3 Hydroelectric Project FERC Project No. P-2337 Initial Study Report: Water Quality May 2015

Transcription

1 Prospect No. 3 Hydroelectric Project FERC Project No. P-2337 Initial Study Report: Water Quality May 2015 Prepared by: PacifiCorp Hydro Resources 925 South Grape Street Medford, OR For Public Review

2 TABLE OF CONTENTS 1.0 INTRODUCTION STUDY DESCRIPTION AND OBJECTIVES PROJECT AREA EXISTING INFORMATION NEXUS TO PROJECT STUDY DESCRIPTION Study Parameters Study Area Sampling Methodology Water Temperature Dissolved Oxygen ph Turbidity Variances from Revised Water Quality Study Plan RESULTS Water Temperature Results Dissolved Oxygen Results ph Results Turbidity Results DISCUSSION REFERENCES APPENDICES Appendix A. Summary of Historical Water Quality Information...23 Appendix B. Specifications for Quality Level A Data 25 Appendix C. Summary of Collected Water Quality Data...28 Initial Study Report: Water Quality Page ii

3 1.0 INTRODUCTION PacifiCorp Energy (PacifiCorp) plans to file an application for new license for the Prospect No. 3 Hydroelectric Project (Project), Federal Energy Regulatory Commission (FERC) project number P FERC s Integrated Licensing Process (ILP) was initiated on July 1, 2013, when PacifiCorp filed a Notice of Intent to File Application for New License (NOI) and a Pre- Application Document (PAD). As part of the ILP, potential applicants are required to file relevant resource management study plans with FERC (18 CFR 5.11 and 5.13). During preparation of the PAD, PacifiCorp reviewed existing information to inform analysis of Project impacts on water quality. Insufficient data were available at certain key locations where potential Project impacts may be greatest. In consideration of available information, PacifiCorp proposed a water quality study to gain information on potential impacts of the Project. The Proposed Water Quality Study Plan was filed with FERC on December 20, 2013 and described the purpose, objectives, approach, and methods for evaluation of the resource. Once public review was received, PacifiCorp addressed the comments and developed the Revised Water Quality Study Plan (Study Plan) to address conditions under 18 CFR 5.13(a). This Initial Study Report (Report) has been prepared pursuant to the Study Plan and provides water quality data enumerated, made presentable, and compared to Oregon Department of Environmental Quality standards. The intent of the Report is to satisfy requirement 18 CFR 5.15(c)(1) of the ILP. Sections 2.0 through 6.0 of this report are a direct reflection of the Study Plan. Unique to the Report are Sections 7.0, 8.0 and Appendix C as they present the results outlined in the Study Plan. 2.0 STUDY DESCRIPTION AND OBJECTIVES Per 18 CFR 5.15(c), this section addresses the goals and objectives of the proposed study. The goal of this Report is to augment the record of water quality data in the Project-affected waters and provide insight for deciding whether additional years of study are needed. This Report addresses proposed study activities in support of a FERC license application for continued operation of the Project. Specific objectives of this Report are to: (1) Report water quality parameters that may be affected by Project operations, which were monitored as described in the Study Plan; (2) Evaluate data for compliance with numeric water quality criteria established by the State of Oregon; and (3) Contribute to an assessment of possible limiting factors for native trout populations in the Study Area. 3.0 PROJECT AREA The Project is located on the South Fork Rogue River, east of the unincorporated community of Prospect in northeast Jackson County, Oregon (Figure 1). The Project occupies private lands Initial Study Report: Water Quality Page 1

4 owned by PacifiCorp and federal lands managed by the Rogue River-Siskiyou National Forest (RR-SNF). The 7.2-megawatt Project operates in run-of-river mode with no significant storage capacity. PacifiCorp maintains a water right in perpetuity from the State of Oregon for 150 cubic feet per second (cfs) from the South Fork Rogue River. Article 402 of the current license requires PacifiCorp to maintain a continuous minimum flow of 10 cfs, or the inflow to the Project, whichever is less, as measured at the gaging station 0.25 mile downstream from the diversion in the South Fork Rogue River. Project facilities that are pertinent to the water quality focus of this Study Plan include: (1) A 172-foot-long, 24-foot-high concrete diversion dam with a 98-foot-long un-gated ogee spillway, located at river mile (RM) 10.5 on the South Fork Rogue River. (2) A 1-acre impoundment at elevation 3,375 feet with a gross capacity of 10-acre-feet. (3) A fish passage facility, including (a) an 86-foot-long, 15-pool concrete ladder for upstream fish passage over the diversion dam; and (b) a 0.25-inch wedge-wire, inclinedplane fish screen with a surface area of 199 square feet located within Project diversion facilities, which transitions to a bypass pipe to return fish to the ladder and facilitate downstream passage. (4) South Fork bypass reach the 10.5-mile-long reach of river subject to reduced flows from project diversion of up to 150 cfs year-round, and operated with a minimum flow requirement of 10 cfs. (5) A 66-inch, 887-foot long woodstave sag pipe that routes flows from the tailrace to the Middle Fork Canal of the Prospect Nos. 1, 2 and 4 Project (FERC No. P-2630). (6) Daniel Creek, from the entries of the overflow discharge from both the forebay spillway and the tailrace to the mouth of Daniel Creek. Water diverted from the South Fork Rogue to the Project powerhouse (Project Water) is conveyed directly from the Project tailrace to the Middle Fork Canal of the Prospect Nos. 1, 2, and 4 Hydroelectric Project (FERC No. P-2630) located to the north of the Middle Fork Rogue. This water ultimately discharges into the North Fork Rogue at North Fork Reservoir. The Project is located primarily on the western slope of the High Cascade Mountains between the South Fork and North Fork Rogue River and includes 895 feet of elevation drop from east to west. The Project alignment transitions from federally owned lands of the RR-SNF to PacifiCorp-owned property, which runs through private timber company holdings and rural developments of the community of Prospect. For the purposes of this document, Project Area is defined as all lands and waters within the existing and proposed FERC Project boundaries. The Project Vicinity is defined as all lands and waters within a two-mile radius of the existing and proposed Project boundaries. The Study Area is defined as the South Fork bypass reach and inflows to Project from the South Fork Rogue River and Imnaha Creek immediately upstream of the Project impoundment. Initial Study Report: Water Quality Page 2

5 Figure 1: Project Location Initial Study Report: Water Quality Page 3

6 4.0 EXISTING INFORMATION Per 18 CFR 5.11(d)(3), during development of the Study Plan, PacifiCorp addressed existing water quality information concerning the Project and the need for additional information. A substantial body of water quality data exists for waters in the Project Vicinity. Information is available from the previous relicensing efforts of the Project (Pacific Power and Light Company, 1986), from license implementation of the neighboring Prospect Nos. 1, 2, and 4 Hydroelectric Project (PacifiCorp, 2012, 2013), and from a water quality study to obtain certfication from the Low Impact Hydroelectic Institute, or LIHI (PacifiCorp, 2013). The results of the various studies are summarized and available in Appendix A. 5.0 NEXUS TO PROJECT Per 18 CFR 5.11(d)(4), this section describes the nexus between Project operations and potential effects on water quality. Project operations divert up to 150 cfs from the South Fork Rogue River at the South Fork diversion dam. The current license stipulates that PacifiCorp must provide a minimum flow of 10 cfs below the diversion dam. The reduction of natural flows in the South Fork bypass reach has the potential to impact water quality, particularly in the upper 2.8 miles of the bypass reach (RM 7.7 to RM 10.5), where water releases at the dam comprise 100 percent of instream baseflows. Although Project operations result in flow reductions throughout the 10.5-mile length of the bypass reach, it is difficult to identify water quality effects below RM 7.7, due to considerable flow augmentation from spring inflows, groundwater contributions, and tributaries. Changes in water quality may affect designated beneficial uses in the South Fork bypass reach, including the health and success of native trout populations. This Study Report presents water quality data collected in the Study Area and identifies and quantifies any potential effects of Project operations on Project-affected waters. 6.0 STUDY DESCRIPTION Per 18 CFR 5.11(b)(1), and 5.11(d)(5), this section provides a detailed study description, including the Study Area, the specific parameters that were studied, the proposed methodology, the specific monitoring and sampling sites, the data collection and analysis techniques, and the timing and duration of sampling activities. 6.1 Study Parameters The proposed study assesses key water quality parameters in the Study Area over a one-year study period. Water quality parameters, selected in consultation with ODEQ, include water temperature, dissolved oxygen (DO), ph, and turbidity. These parameters were selected because they are important to aquatic life, as summarized in Table 1. Initial Study Report: Water Quality Page 4

7 Table 1. Description of water quality parameters. Parameter Significance Applicable Standard Water temperature Water temperature controls reaction rates in aquatic systems. Elevated water temperatures in the South Fork Rogue River could be a stressor to native rainbow and cutthroat trout populations. ODEQ has developed standard temperature criteria to protect native trout populations. OARS Dissolved oxygen (DO) ph Turbidity DO is critical to the biological community in surface waters and is a key element of healthy aquatic habitat. Low DO concentrations can be a stressor to aquatic life. ODEQ has identified life-stage specific DO criteria to protect native trout spawning, rearing, and migration. ph influences the solubility and form of nutrients and heavy metals in waters, and determines the bioavailability of these dissolved materials to aquatic life. At extreme ph levels (approximately less than 4.5 or greater than 9), these dissolved substances can become toxic. To protect the health of aquatic stream life, ODEQ developed basin-specific ph criteria. Elevated turbidity levels due to increases in suspended materials such as clay and silt may obstruct the gills of aquatic organisms or may smother fish eggs and macroinvertebrates as the particles settle. To protect aquatic life, ODEQ has established provisions for allowable turbidity increases over background levels during turbidity-causing activities. OARS OARS OARS Study Area The Study Area includes the South Fork bypass reach and inflows to Project from the South Fork Rogue River and Imnaha Creek. Water quality conditions in the upper 2.8 miles of the bypass reach (RM 7.7 to RM 10.5) are of particular interest. In this 2.8-mile reach, water releases at the diversion dam comprise 100 percent of instream baseflows; there are no contributions from springs, groundwater inflows, or tributaries. The Study Area includes five water quality monitoring stations (Table 2). The sampling stations, shown in Error! Reference source not found. were chosen for their ability to represent conditions in the Study Area and to assess potential Project effects on water quality. Table 2. Water quality monitoring stations and associated codes. Sample Site Description Location Associated Code South Fork Rogue River Inflow to Project RM 10.8 SFRI Imnaha Creek Inflow to Project RM 0.2 IMCI South Fork Bypass Reach - Upper End (Below release point at diversion dam) South Fork Bypass Reach - Mid-Reach (Above influence of springs and groundwater contribution) South Fork Bypass Reach - Lower End (Below influence of springs and groundwater contributions) RM 10.5 RM 10.0 RM 7.0 SFBU SFBM SFBL Initial Study Report: Water Quality Page 5

8 Hazardous access prevented installation of monitoring equipment at the location proposed in the Study Plan for monitoring site SFBM (RM 8.5). The monitoring site was relocated upstream to RM 10.0 where reliable, safe access allowed consistent data collection throughout the study season. Figure 2. Water quality monitoring stations. 6.3 Sampling Methodology The following methodologies were taken directly from the Study Plan. While most of these methodologies were followed, some variances did occur and are described in Section 6.4. Monitoring of the proposed parameters was planned for May 1, 2014 through May 1, 2015 to encompass a range of conditions, including the summer months when: (1) stream temperatures and DO are most likely to be compromised by low base flows and high ambient temperatures, and (2) scheduled maintenance is likely to occur, which may contribute to turbidity changes. Table 3 provides schedules, locations, and summarized sampling techniques for temperature, DO, ph, and turbidity. In the subsections that follow, sampling methodology is described in detail for each parameter. Sampling methodology was consistent with ODEQ s provisions for Initial Study Report: Water Quality Page 6

9 attaining Quality Level A data. Applicable instrument specifications and QA/QC procedures developed by ODEQ are summarized in Appendix B, and fully described in the Water Monitoring and Assessment Mode of Operations Manual (ODEQ, 2009). Table 3. Water quality parameters and sampling techniques for the proposed study. Parameter Monitoring Station Sampling Technique Water Temperature SFRI, IMCI, SFBU, SFBM, SFBL Continuously record hourly values for 1 year, beginning on May 1, Dissolved Oxygen SFBU, SFBM, SFBL Continuously record hourly values for 72 hours, performed between May 1-15 (trout fry emergence), and repeated in July, August, September, and October. ph SFBU, SFBM, SFBL Continuously record hourly values for 72 hours, performed between May 1-15, and repeated in July, August, September, and October. Turbidity SFRI, IMCI, SFBU Continuously record 15-minute values for a 24-hour period during scheduled Project maintenance activities that necessitate spill at the diversion dam Water Temperature Temperature monitoring was performed with Onset Tidbit thermographs at SFRI, IMCI, SFBU, SFBM, and SFBL. Prior to deployment, the thermographs were pre-programmed to start logging temperatures at a synchronized time. A pre-deployment thermograph audit (see Appendix B) was performed to ensure instrument accuracy and precision met ODEQ criteria for Quality Level A data. With the exceptions noted in Section 6.4, temperatures were continuously monitored beginning on May 1, Thermographs were deployed at least one day prior to the May 1 start date. Deployment notes included: (1) the monitoring station name; (2) time and date of deployment; (3) the serial number of the thermograph; (4) in-situ water temperature, measured with a calibrated Traceable thermometer; and (5) weather conditions. Thermographs were placed at the thalweg to avoid dewatering as flows recede during the summer. Periodic field audits were performed at times when the sites were safely accessible. The thermographs were inspected to ensure that they were operational and submerged. Data was downloaded during each field audit, and instrument accuracy was confirmed with an in-situ temperature reading from a NIST-traceable thermometer. Stream temperature data lend themselves well to descriptive statistical analysis (mean, ranges, standard deviation, etc.), as well as more rigorous analysis and modeling. For purposes of this study, graphs were developed showing hourly data. Tabular summaries of the 7DMAX temperatures were used to assess compliance with Oregon s applicable numeric criteria. The 7DMAX acts to remove some of the daily fluctuations in the temperature profile and provides more insight into site-specific trends. The 7DMAX is calculated by first developing the daily (24-hour) maximum temperatures, then determining rolling averages of these values for the day, the preceding three days, and the following three days. Data from SFRI and IMCI provided background information used in the interpretation of temperature data in the bypass reach. Initial Study Report: Water Quality Page 7

10 6.3.2 Dissolved Oxygen Calibrated, multi-parameter YSI datasondes were used to monitor DO at SFBU, SFBM, and SFBL. Datasondes recorded hourly DO levels for 72 consecutive hours at each site. Prior to deployment, datasondes were calibrated and programmed for synchronized start times and sampling frequencies. Pre-deployment QA/QC procedures were observed to attain Quality Level A data, as described in Appendix B. The initial deployment between May 1 and May 15, to characterize DO conditions during the native trout spawning/emergence period, was not achieved in the first study season, but this period will be monitored in the second study season (2015). Deployments were completed in July, August, September, and October to monitor DO during the months when the oxygen saturation potential is likely to be lowest due to seasonal environmental conditions such as elevated water temperatures, and low instream flows. Deployment notes included the time of initial placement in the stream, weather conditions, and barometric pressure. In addition, the serial number of the logger placed at the location was recorded. Scatter plots or line graphs of the DO data over the 72-hour monitoring periods are plotted against the applicable minimum instantaneous concentration noted above. Means and ranges at each of the sites are presented below in tabular format ph ph was monitored concurrently with DO at SFBU, SFBM, and SFBL. The same calibrated YSI datasondes used for DO also measured ph. As such, hourly ph readings will be collected for 72 consecutive hours at each site. The initial deployment between May 1 and May 15 was not achieved in the first study season, but this period will be monitored in the second study season (2015).. Deployments were repeated in July, August, September, and October to monitor ph during the months when processes that affect ph, such as decomposition and primary production, are likely to be greatest due to increased solar radiation and elevated water temperatures. Instrument specifications for ph sensors and pre-deployment procedures for datasondes (Appendix B) were observed to attain ODEQ Quality Level A data. ph results are summarized as 24-hour minimum and maximum values. Results are presented below in tabular format Turbidity Turbidity monitoring occurred during the first planned Project maintenance activity that necessitated ramping below the diversion dam on September 8, Turbidity was monitored at SFBU, where any potential changes in turbidity levels due to Project operations can be readily detected. Additionally, background turbidity levels were monitored in SFRI and IMCI. Turbidity was monitored at 0.25-hour intervals for a 24-hour period before, during, and after the ramping event. Instrument specifications for turbidity sensors and pre-deployment procedures for datasondes (Appendix B) were observed to attain ODEQ Quality Level A data. At the same time that the datasondes are deployed, a pressure transducer was to be placed at SFBU. The stage readings from the pressure transducer were supposed to be used to describe the duration, overall magnitude (total stage change per event), and the ramp rate (stage change per unit time) of the ramp event. However, the pressure transducer was not utilized during the turbidity monitoring. In lieu of the pressure transducer, PacifiCorp utilized the existing Initial Study Report: Water Quality Page 8

11 equipment and real-time data output from USGS Gage located approximately 0.3 miles downstream of the diversion within the South Fork Rogue River bypass. A graphical analysis, wherein upstream and downstream turbidity readings are plotted against stage, provides a clear visual representation of any potential Project effects on turbidity. The percent change in turbidity levels between SFRI and SFBU was calculated for each 0.25-hour interval. These percent change figures are summarized as the average, minimum, and maximum for each operational phase (i.e., before ramping, during ramping, and after ramping). Turbidity data from IMCI is also referenced in the interpretation of results. 6.4 Variances from Revised Water Quality Study Plan Revised Study Plan comments were received from stakeholders on or before May 13, 2014, and FERC s Study Plan Determination was issued on May 27, In light of these ILP milestones, full implementation and deployment of all water quality measuring devices by PacifiCorp was not consistent with the May 1, 2014 start date defined in the Plan. However, a full year of continuous data as required by the Plan will ultimately be collected through continued implementation beyond the preparation of this Initial Study Report and into the second study season. Hazardous access prevented installation of monitoring equipment at the location proposed in the Study Plan for monitoring site SFBM (RM 8.5). The monitoring site was relocated upstream to RM 10.0 where reliable, safe access allowed consistent data collection throughout the study season. As described in Table 3, hourly water temperatures were to be continuously recorded for 1 year, beginning on May 1, 2014 for each of the monitoring sites. This requirement has been met for the SFRI, IMCI, SFBU and SFBL monitoring sites from May 1, 2014 to date of the latest data downloads on March 13, This requirement was not met in the first study year at monitoring site SFBM as data collection was initiated on May 12, DO monitoring periods of 72-hours were originally intended to start in May 2014 and continue on a monthly basis from July through October 2014 (Table 3). During the May 2014 DO monitoring event, data was only collected at the SFBU site. That is, sites SFBM and SFBL are absent DO data for May All other DO data collection and reporting requirements as described in the Study Plan Study Plan have been met. The May 1 through May hour monitoring will be accomplished at SFBU, SFBM, and SFBL in As described in Section 6.3.3, 72-hour ph monitoring periods were to be conducted concurrently with DO measurements. Consequently, SFBM and SFBL are absent ph data for the May 2014 sampling period. The May 1 through May hour monitoring will be accomplished at SFBU, SFBM, and SFBL in As described in Section a pressure transducer was to be placed at SFBU to describe the duration, overall magnitude, and ramp rate of any ramping event into the South Fork Rogue River bypass. However, the pressure transducer was not utilized during the turbidity monitoring. In lieu of the pressure transducer, PacifiCorp utilized the existing equipment and real-time data Initial Study Report: Water Quality Page 9

12 output from USGS Gage located approximately 0.3 miles downstream of the diversion within the South Fork Rogue River bypass. 7.0 RESULTS The results of this Initial Study Report are preliminary and do not represent the full sampling periods required by the Study Plan. Due to the time constraints involved in reviewing data, preparing the Initial Study Report, and filing the report on or before the FERC ILP deadline of May 12, 2015, the Initial Study Report includes data collected from May 1, 2014 through March 13, 2015, with exception of the variances noted in Section 6.4. The subsequent Updated Study Report, to be provided on or before May 11, 2016, will include the full sampling periods required by the Study Plan. 7.1 Water Temperature Results To date all 7DMAX data from each monitoring site demonstrate compliance with Oregon s numeric criteria of a 7DMAX temperature of 18 C (Table 4). The largest 7DMAX of C occurred on July 17, 2014 at the SFBM monitoring site. The SFBM site is the furthest site downstream of the diversion dam that is not influenced by groundwater inflows, likely making it the most susceptible site to increased water temperatures via solar radiation. Given this, the maximum 7DMAX of C at SFBM is still well below Oregon s criteria of 18 C. All 7DMAX temperatures are shown in graphical form in Error! Reference source not found.. Table 4. Summary of 7DMAX temperatures per monitoring site. Metric 7DMAX Temperatures IMCI SFRI SFBU SFBM SFBL Maximum Minimum Average In general, water temperatures immediately downstream of the diversion at SFBU were slightly colder in the summer season and slightly warmer in the winter season than water temperatures in the South Fork Rogue above the diversion at SFRI (Figure 3). This is to be expected as Imnaha Creek inflows appear to be less influenced by seasonal weather patterns (i.e., Imnaha Creek water is colder during summer and warmer during winter) than the temperatures observed at SFRI. During the summer season, and without any significant groundwater or lateral inflows between SFBU and SFBM, PacifiCorp observed SFBM temperatures to be slightly warmer than temperatures at SFBU. Temperatures at SFBL showed a more seasonally stable regime due to groundwater influence. Initial Study Report: Water Quality Page 10

13 Figure 3. 7DMAX temperatures of each monitoring site. 7DMAX Temperature (C) DMAX Temperatures SFRI IMCR SFBU SFBM SFBL ODEQ Standard Date Hourly variations and daily averages of water temperatures were plotted for each study site (Figures 4 8). The daily average temperatures are displayed over hourly temperatures, which exhibit diurnal swings of amplitude as a result of solar radiation. The maximum observed hourly temperature was C recorded at SFBM and occurred on July 17, Figure 4. IMCI hourly and daily average temperatures. Temperature (C) Imnaha Creek Temperature (IMCI) Hourly Temp Daily Average Date Initial Study Report: Water Quality Page 11

14 Figure 5. SFRI hourly and daily average temperatures. Temperature (C) SF Rogue Temperature Upstream of Diversion Dam (SFRI) Hourly Temp Daily Average Date Figure 6. SFBU hourly and daily average temperatures. Temperature (C) SF Rogue Upper Bypass Temperature (SFBU) Hourly Temp Date Initial Study Report: Water Quality Page 12

15 Figure 7. SFBM hourly and daily average temperatures. Temperature (C) SF Rogue Middle Bypass Temperature (SFBM) Hourly Temp Daily Average Date Figure 8. SFBL hourly and daily average temperatures. 14 SF Rogue Lower Bypass Temperature (SFBL) Temperature (C) Hourly Temp Daily Average 2 0 Date 7.2 Dissolved Oxygen Results DO levels recorded at each monitoring site demonstrate compliance with Oregon s minimum numeric criteria of 8.0 mg/l (Table 5; Error! Reference source not found. 14). Mean hourly DO readings at SFBU, SFBM, and SFBL ranged from 9.55 to mg/l throughout the monitoring period of May through October. The month of July had the lowest 72-hour mean DO readings overall with values of 9.85, 9.55, and mg/l for SFBU, SFBM, and SFBL, respectively (. Initial Study Report: Water Quality Page 13

16 Table 5). The minimum observed hourly DO measurement was 9.07 mg/l and was recorded at SFBM on July 10, DO readings taken at each site and during each sampling period appeared to have a sinusoidal pattern in which the wavelength is approximately equal to one day. The crests and troughs of the DO curves were inversely proportionate to daily water temperature swings (i.e., the highest daily points of DO coincided with the lowest daily points of temperature, and vice versa; Error! Reference source not found. 14). PacifiCorp also suspects that flora and fauna DO production and consumption, respectively, contributed to the observed sinusoidal patterns of DO levels. Table 5. Mean and ranges of hourly DO (mg/l) readings for each site. Site May Period June Period July Period Aug. Period Sept. Period Oct. Period Mean Range Mean Range Mean Range Mean Range Mean Range Mean Range SFBU SFBM N/A N/A SFBL N/A N/A Figure 9. May 72-hour dissolved oxygen readings May DO Sampling Period Dissolved Oxygen (mg/l) SFBU ODEQ Minimum Date Initial Study Report: Water Quality Page 14

17 Figure 10. June 72-hour dissolved oxygen readings June DO Sampling Period Dissolved Oxygen (mg/l) SFBU SFBM SFBL ODEQ Minimum Date Figure 11. July 72-hour dissolved oxygen readings July DO Sampling Period 11 Dissolved Oxygen (mg/l) SFBU SFBM SFBL ODEQ Minimum 7.5 Date Initial Study Report: Water Quality Page 15

18 Figure 12. August 72-hour dissolved oxygen readings. Dissolved Oxygen (mg/l) August DO Sampling Period SFBU SFBM SFBL ODEQ Minimum Date Figure 13. September 72-hour dissolved oxygen readings. Dissolved Oxygen (mg/l) September DO Sampling Period Date SFBU SFBM SFBL ODEQ Minimum Initial Study Report: Water Quality Page 16

19 Figure 14. October 72-hour dissolved oxygen readings October DO Sampling Period Dissolved Oxygen (mg/l) SFBU SFBM SFBL ODEQ Minimum Date 7.2 ph Results All ph data gathered at each monitoring site complied with the standard ph of 6.5 to 8.5 for estuarine and fresh waters in the Rogue basin (OAR , Table 6 8). Minimum and maximum ph values typically ranged from 7 to 8 at all sites, with some spatial and seasonal variation. Table hour minimum and maximum ph values for May and June sampling periods. May Sampling Period June Sampling Period 5/13/2014 5/14/2014 5/15/2014 6/6/2014 6/7/2014 6/8/2014 Site Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. SFBU SFBM n/a n/a n/a n/a n/a n/a SFBL n/a n/a n/a n/a n/a n/a Initial Study Report: Water Quality Page 17

20 Table hour minimum and maximum ph values for July and August sampling periods. July Sampling Period August Sampling Period 7/9/2014 7/10/2014 7/11/2014 8/28/2014 8/29/2014 8/30/2014 Site Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. SFBU SFBM SFBL Table hour minimum and maximum ph values for September and October sampling periods. September Sampling Period October Sampling Period 9/2/2014 9/3/2014 9/4/ /24/ /25/ /26/2014 Site Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. SFBU SFBM SFBL Turbidity Results On September 8, 2014 there was an outage at the Project resulting in closure of the diversion headgate and release of approximately 62 cfs of water (i.e., the full inflow upstream of the diversion) into the South Fork Rogue bypass reach. This volume of water continued to flow into the bypass reach until September 17, Turbidity measurements were recorded during the first 48 hours of this event. These measurements were used to address concerns regarding ramping, or the first initial increase in flows and river stage, and the resulting influence of ramping events on turbidity in the South Fork bypass reach. As expected, there was a slight increase in turbidity at the SFBU monitoring site during the beginning of ramping (Error! Reference source not found.). Beginning on September 8, 2014 at 0615 hours, turbidity levels at SFBU increased above the SFBU background condition for 1.75 hours (Error! Reference source not found.). However, despite the steep increase in turbidity, turbidity levels remained very low throughout the event, peaking at just 4.3 NTU. Initial Study Report: Water Quality Page 18

21 Figure 15. Turbidity of SFBU and SFRI during the September 8, 2014 P3 ramping event SF Rogue Turbidity During P3 Ramping Event Q (CFS) SF Bypass Flow SF Above Impound Turbidity SFBU Turbidity IMCI Turbidity Turbidity (NTU) /7/2014 0:00 9/7/ :00 9/8/2014 0:00 9/8/ :00 9/9/2014 0:00 9/9/ :00 Shown below in Table 9 are average, minimum, and maximum values of percent changes in turbidity between SFRI and SFBU during each operational ramping phase (i.e., before ramping, during ramping, and after ramping). OAR establishes a maximum cumulative increase in natural stream turbidities of 10% compared to background conditions. One data point (on a 0.25 hour interval) exceeded this standard as the turbidity in SFBU was 56.4% greater than that of SFRI. Table 9. Percent changes of turbidities during the ramping between SFRI and SFBU. A negative percentage indicates SFBU had lower turbidity than SFRI above the impoundment. Metric Before Ramping During Ramping After Ramping Average Percent Change % -59.6% % Minimum Percent Change % % % Maximum Percent Change -92.1% 56.4% -74.4% 8.0 DISCUSSION Recorded temperatures in the study reach did not exceed the 7DMAX standard of 18 C. For perspective, no single hourly temperature exceeded the 7DMAX (maximum recorded hourly temperature was C at SFBM on July 17, 2014). Because the 7DMAX is calculated by averaging the maximum hourly temperatures of seven consecutive days, it would take extreme weather and flow conditions for 7DMAX exceedances to occur within the study reach. Recorded DO concentrations did not violate the 8.0 mg/l minimum DO standard. Data for the SFBM and SFBL sites was not collected for the May monitoring period in However, considering monitoring periods in June through October, wherein data are available for all sites, Initial Study Report: Water Quality Page 19

22 there was little DO variation observed between the sites. Hourly DO differences were evaluated between SFBM and SFBU as well as between SFBL and SFBU. On average, DO at SFBM was 0.19 mg/l less than DO at SFBU, with standard deviation of 0.15 mg/l. On average, DO at SFBL was 0.78mg/L greater than DO at SFBU, with standard deviation of 0.67 mg/l. Given the low DO variance between sites and considering SFBU DO data recorded during the May monitoring period had a mean and range of and 1.07 mg/l, respectively. It is unlikely DO standards were violated at the SFBM and SFBL sites during the May monitoring period. ph results display a stable regime within and between the monitoring sites (Section 7.2). No ph standards were violated during the study, however, ph data were not collected for the May monitoring period. To make inference on the probable values of these missing data, all the hourly ph data gathered from each site in 2014 was pooled into one set. The mean ph of the pooled data set was 7.58 with a standard deviation of 0.197, supporting that ph in the South Fork Rogue bypass is a stable regime. The ph standard for the Rogue basin is Considering the breadth of this ph standard, to violate standards a given ph value within the South Fork bypass study reach would have to vary 4.7 standard deviations about the observed mean on the basic side and 5.5 standard deviations about the observed mean on the acidic side. For these reasons, it is unlikely that ph standards were violated at the SFBM and SFBL sites during the May monitoring period. During the ramping event on September 8, 2014, turbidity standards (i.e., maximum of 10% cumulative increase of background conditions) in the South Fork Rogue bypass were exceeded (56.4% increase) during one 0.25 hour interval data point. During and after ramping, turbidity cleared quickly, as the turbidity levels were elevated for just 1.75 hours from 0615 hours to 0800 hours (peak of 4.3 NTU). Although turbidity standards were violated, the clear water background conditions of the South Fork Rogue above the diversion, the low NTU value of the data point out of compliance (4.3 NTU), and the mathematical nature of percent changes when considering small values suggest that turbidity impacts were negligible. To address missing data from the first year of field studies, PacifiCorp will continue monitoring temperature data through May 12, 2015 at SFBM as well as DO and ph at SFBM and SFBL between May 1 through May 15, 2015, thereby providing data sets representative of one full year as detailed in the Study Plan. PacifiCorp will include the complete data sets of water quality parameters in in the Updated Study Report, due May 11, In conclusion, with exception for the single ramping turbidity point out of compliance, all available data met compliance standards. Additionally, no patterns or trends were detected in these data that imply standards may be violated during meteorological or hydrological conditions otherwise unrepresented in the available data. In light of the water quality data produced by this study, it is unlikely that the water quality parameters monitored in the South Fork Rogue River bypass reach are limiting factors for native trout populations in the Study Area. PacifiCorp suggests that data collected during year one of the field study sufficiently describe water quality 1 Completed data sets will include data shown in this Initial Study Report as well as data unavailable during development of this Initial Study Report. Unavailable data refers to periods from the latest meter downloads to the end of year one of the field studies, or from March 13, 2015 through May 1, 2015, extending to May 12, 2015 for temperature at SFBM and between May 1 through May 15, 2015 for both DO and ph at SFBM and SFBL. Initial Study Report: Water Quality Page 20

23 conditions within the Study Area. Therefore, PacifiCorp does not propose any additional field studies. Initial Study Report: Water Quality Page 21

24 9.0 REFERENCES ODEQ. (2009). Water Monitoring and Assessment Mode of Operations Manual, DEQ03-LAB SOB (Version 3.2). Hillsboro, OR. ODEQ. (2009(b)). Data Quality Matrix, DEQ04-LAB-0003-QAG (Version 4.0). Retrieved from Oregon Department of Environmental Quality Web site: ODEQ. (2013). Letter to PacifiCorp: Comments Regarding Compliance Monitoring for LIHI Certification, P3 Hydroelectric Project. Eugene, OR. Pacific Power and Light Company. (1986). Application for New License, Prospect No. 3 Hydroelectrict Project (Volume II: Environmental Studies). Portland. PacifiCorp. (2012). Prospect Nos. 1, 2, and 4 Hydroelectric Project: Final Water Quality Report Medford, OR. PacifiCorp. (2013). Compliance Monitoring for LIHI Certification, Prospect No. 3 Hydroelectric Project. Medford, OR. PacifiCorp. (2013). Prospect Nos. 1, 2, and 4 Hydroelectric Project: 2012 Addendum to Final Water Quality Report. Medford, OR. PacifiCorp. (2014). Prospect No. 3 Hydroelectric Project. Revised Study Plans Water Quality Report. Medford, OR. Initial Study Report: Water Quality Page 22

25 Appendix A. Summary of Historical Water Quality Information Table A-1. Summary of 7DMAX water temperatures in Project Vicinity (Pacific Power and Light Company, 1986, PacifiCorp, 2012, 2013). Location Year Sampling Period Max 7DMAX Temperature ( C) South Fork Bypass RM May 1 Oct South Fork Bypass RM Sep 2 Oct South Fork Bypass RM May 1 Oct South Fork Bypass RM May 1 Oct South Fork Bypass RM Jun 1 - Oct South Fork Bypass RM Jul 23 - Aug South Fork Bypass RM Jun 1 - Oct South Fork Rouge River RM 10.8 (Project Inflow) South Fork Rouge River RM 10.8 (Project Inflow) 2012 Jun 1 - Oct Mar 13 - Oct Imnaha Creek (Project Inflow) 2012 May 6 - Jul Imnaha Creek (Project Inflow) 1986 Mar 14 - Sept Dissolved Oxygen Dissolved oxygen (DO) levels in Project-affected waters were measured in continuous, hourly 72-hour sampling events during implementation of the license for the Prospect Nos. 1, 2, and 4 Project and during the LIHI certification study. The available DO data in Project-affected waters are summarized as the minimum level measured during each sampling event (Table A-2). All available data demonstrate compliance with the applicable state numeric criteria of a minimum DO concentration of 8.0 mg/l (OARS ). Table A-2. Summary of minimum hourly dissolved oxygen levels in waters of Project Vicinity (PacifiCorp, 2012, 2013). Location Year Sampling Period Minimum DO (mg/l) Oregon Standard DO (mg/l) South Fork Bypass RM Jul 7 - Jul South Fork Bypass RM Jun 7 - Jun South Fork Bypass RM Jul 13 - Jul South Fork Bypass RM Aug 13 - Aug Turbidity Turbidity in Project-affected waters was measured to support LIHI certification. Turbidity levels were extremely low (<1.0 NTU) throughout the study period. Table A-3 summarizes paired Initial Study Report: Water Quality Page 23

26 turbidity samples, such that average background turbidity (upstream of Project) can be compared to turbidity in the bypass reach. OAR establishes a maximum cumulative increase in natural stream turbidities of 10%, compared to background conditions. The available data indicate that turbidity conditions in the South Fork bypass reach are generally lower than background conditions. An exceedance of Oregon s numeric criteria observed on July 9, 2012 was attributed to normal variation in natural turbidity (ODEQ, 2013). Table A-3. Discrete monthly turbidity levels in Project Vicinity provided in nephelometric turbidity units (NTU) (PacifiCorp, 2013). Location 5/8/2012 6/6/2012 7/9/2012 8/13/2012 9/17/ /30/2012 Imnaha Creek South Fork Rogue RM South Fork Bypass RM ph PacifiCorp monitored ph levels in the Project Vicinity to support LIHI certification. OAR identifies a ph range of 6.5 to 8.5 for estuarine and fresh waters in the Rogue basin. All ph values observed during the LIHI study comply with the basin-specific numeric criteria (Table A-4). Table A-4. Discrete monthly ph levels in Project Vicinity (PacifiCorp, 2013). Location 5/8/2012 6/6/2012 7/9/2012 8/13/2012 9/17/ /30/2012 Imnaha Creek South Fork Rouge RM South Fork Bypass RM Other Parameters Additional water quality parameters measured during the 2012 LIHI study include total dissolved solids (TDS) and toxic substances (arsenic, cadmium, chloride, chromium, copper, iron, lead, mercury, nickel, selenium, silver, and zinc). The maximum TDS level observed at all locations was 6.8 mg/l, substantially lower than the state numeric criteria of 500 mg/l (OAR ). Of the toxic substances sampled, only iron, lead, and nickel were detected, and all values were well below the levels considered chronically harmful to aquatic life by ODEQ. Initial Study Report: Water Quality Page 24

27 Appendix B. Specifications for Quality Level A Data This Study Plan adopts applicable QA/QC procedures described in the Water Monitoring and Assessment Mode of Operations Manual (ODEQ, 2009). QA/QC procedures will be observed to collect field data that are consistent with ODEQ s criteria for level A data quality (ODEQ, 2009(b)). Water Temperature For temperature monitoring, Onset Tidbit thermographs or an equivalent device capable of continuous digital monitoring and storage of temperature data at user-specified frequencies is required. In accordance with level A data quality, accuracy and precision of the thermographs should be ±0.5 ºC. Devices should have a temperature range appropriate for the environment to be monitored. Onset Tidbits have a measurement range of -5 ºC to 35 ºC, which is suitable for this project. Thermographs to be used on this project are not user-calibrated (they are factory calibrated prior to shipment); however, as a QA/QC measure, thermographs must be checked against known temperatures prior to deployment. A pre-deployment temperature check can be performed using the same techniques recommended by ODEQ for testing instrument accuracy and precision (ODEQ, 2009). Per ODEQ s recommendations, at least two pre-deployment temperature checks will be performed between 5 ºC and 25 ºC. Ice or warm water will be used to adjust water baths to desired temperatures. Temperature checks will be done in a stable thermal mass, such as a water-filled thermos bottle or closed cooler. Field thermographs will be compared to a NIST (National Institute of Standards and Technology) traceable thermometer accurate to ±0.2 ºC or a field thermometer accurate to ±0.2 ºC or better. During these pre-deployment temperature checks, the loggers will be programmed to record at 30-second intervals and immersed in water baths allowed to stabilize for approximately 1-hour. The thermographs will log temperatures within the bath over a 10-minute period, while temperatures are simultaneously recorded with a NIST thermometer. Water temperatures should not vary by more than 0.5 ºC between the NIST recorded temperature and the thermograph s temperature. Units that do not pass the accuracy test should be retested and replaced if criteria still cannot be met. Once the logger passes the tests it will be set to record at 1-hour intervals for the duration of the monitoring period. At least two supplementary field temperatures QA audits will be conducted; one after the first month of deployment, and one just before temperature units are removed from the stream. Monitoring sites will be visited monthly to download temperature data and verify that the thermographs are operational and submerged. In addition to water temperature, an air temperature sensor will be deployed at a structure within the vicinity of the stream monitoring location to provide local correlation of air and water temperature. An air temperature data logger housed in a solar radiation shield to reduce the influence of reflected heat will be used for this purpose. Initial Study Report: Water Quality Page 25

28 Dissolved Oxygen To attain level A data quality for DO, ODEQ requires either Winkler titration or a calibrated oxygen meter (2009). A calibrated oxygen meter is the favored approach for continuous, unattended monitoring. PacifiCorp will use a YSI brand multi-parameter datasonde with a calibrated ROX optical DO sensor to attain the accuracy and precision criteria for level A dissolved oxygen data (A ±0.2 mg/l, P ±0.3 mg/l). Prior to deployment, the unit must pass calibration tests. Calibration will be performed according to the specific instructions in the operator s manual. The state of Oregon has established the following six steps for datasonde deployment that, when followed, help ensure the collection of quality data: (1) Enabling the data sonde to measure the parameter of interest The appropriate operator s manual should be consulted for this step. (2) Pre-deployment check to ensure all systems are set up and capable of completing the monitoring The operator must verify that: Battery voltage is sufficient; Previously stored data are downloaded and erased from the datasonde to ensure sufficient memory for the collection of new data; The unit has passed calibration; The unit is operating at the correct date and time; The unit is programmed to begin logging at the desired time and interval; Proper record-keeping procedures have been developed; and The file name can be clearly identified within the first eight characters. (3) Programming the unit to record the appropriate parameters at the desired intervals The appropriate operator s manual should be consulted again for Step 3; however, it can be generally acknowledged that datasondes should be programmed to collect at least one measurement prior to deployment to ensure that the logging function performs as intended. (4) Deployment of datasonde Datasonde deployment, involves evaluations to ensure the safety of the proposed site, the availability of a structure for anchoring the datasonde, and an adequate depth (one meter is recommended when practical). The datasonde shall be deployed in steel or PVC casing that can be locked and affixed to an immobile structure to protect the unit from floating debris and vandalism. The casing must be perforated near the datasonde sensors to ensure adequate flow across the sensor(s). Initial Study Report: Water Quality Page 26

29 (5) Field audit measurements for QA; The audit measurement, listed as Step 5, verifies the representativeness of datasonde values during deployment conditions. PacifiCorp proposes pre- and post-deployment sensor calibration in lieu of field audits. If PacifiCorp elects to monitor longer than the proposed duration of 72 hours, then more frequent, e.g., weekly maintenance and calibrations will be needed. Such calibrations shall fulfill the role of field audits; further, a calibrated DO meter will permit data collection methods within the provisions of ODEQ s Level-A data quality. (6) Recovery to download data recorded during the monitoring event. ph To attain level A data quality for ph, ODEQ requires the use of a calibrated ph electrode (2009). PacifiCorp will use a YSI brand multi-parameter datasonde with a calibrated ph electrode to attain the accuracy and precision criteria for level A dissolved oxygen data (A ±0.2 S.U., P ±0.3 S.U.). The ph electrode will be affixed to the same datasonde used for DO monitoring. As such, all of the QA/QC procedures described previously for DO shall also be applied to the ph electrode. Turbidity Turbidity shall be measured with a YSI turbidity sensor affixed to a datasonde. The sensor must be calibrated prior to use. PacifiCorp will adhere to calibration procedures described in the operator s manual. To attain ODEQ s requirements for level A, sensor accuracy should be ±5% of standard value and precision should be ±5%. Because the turbidity sensor is affixed to a YSI datasonde, all applicable QA/QC procedures described previously for DO will be used for the turbidity sensor. Initial Study Report: Water Quality Page 27