United States Department of the Interior

U. S. GEOLOGICAL SURVEY Oregon Water Science Center 2130 SW 5th Avenue Portland, Oregon 97201 https://www.usgs.gov/centers/or-water

October 1, 2020

Diane Taniguchi-Dennis Chief Executive Officer Clean Water Services 2550 SW Hillsboro Highway Hillsboro, OR 97123

Dear Ms. Taniguchi-Dennis:

Enclosed for your approval is the Fiscal Year 2021 (October 1, 2020 to September 30, 2021) Scope of Work for continuation of the cooperative study in the Tualatin River basin between Clean Water Services (District) and the U.S. Geological Survey (USGS). The program was developed through consultation between District and USGS personnel and includes basic data collection as well as new and continuing investigations that target some of the most important scientific and resource management issues in the Tualatin River basin.

Highlights of the 2021 work plan include (1) year 3 of a 3-year study to monitor and manage algal communities at Fernhill Wetlands and their downstream effects in the Tualatin River, (2) continued real-time water-quality monitoring at 6 stream sites, (3) year 2 of a 3-year study to monitor turbidity and suspended sediment in Chicken Creek

The total cost for USGS personnel to accomplish these work elements in Fiscal Year 2021 is $493,770. The study will be jointly funded by the District ($296,262) and by USGS Cooperative Matching Funds ($197,508). The imbalance between District (60%) and USGS (40%) funding levels is due to the limited availability of USGS matching funds; additional details are provided in the attached Scope of Work. The table on the next page summarizes the work elements and the proposed funding levels for each task during this period.

Enclosed in the Scope of Work is a list of all USGS reports that have been produced from previ- ous Tualatin River Basin Studies. Over the years, thirty-four scientific papers have been published from the Tualatin program, with another eight in progress and nearing completion. Publishing the findings from these investigations remains one of our top priorities.

FISCAL YEAR 2021 EXPENSES FOR TUALATIN RIVER BASIN STUDIES

WORK ELEMENT DISTRICT USGS TOTAL

1. Provide support for District laboratory in national USGS QA 2,130 1,420 3,550 programs and supply a certified chlorophyll standard.

2. Monitor air and water temperature (two sensors), pH, 38,610 25,740 64,350 specific conductance, dissolved oxygen (two sensors), turbidity, chlorophyll, phycocyanin, and barometric pressure at the Oswego Dam.

3. Monitor water temperature (two sensors), pH, specific 24,813 16,542 41,355 conductance, and dissolved oxygen (two sensors at river mile 24.5.

4. Monitor solar insolation at the Durham Treatment Facility. 5,391 3,594 8,985

5. Collect and report TVID water withdrawals at the Spring Hill 0 0 0 Pump Plant. (no charge)

6. Monitor water temperature, pH, specific conductance, 102,348 68,232 170,580 dissolved oxygen, and turbidity in four Tualatin River tributaries with the addition of fDOM, phycocyanin and chlorophyll at the Scoggins monitor

7. Assist with water-quality monitor int the Tualatin River at 10,080 6,720 16,800 Highway 219.

BASIC PROGRAM SUBTOTAL $ 173,292 $ 115,528 $ 288,820

8. Import District water-sample data from 2019 and other 3,618 2,412 6,030 miscellaneous periods into the USGS NWIS database.

9. Attend meetings related to the Wapato Lake NWR restoration 2,589 1,726 4,315 project, and provide expertise.

10. Provide technical expertise and monitoring to support adaptive 83,778 55,852 139,630 management at Fernhill Wetlands to foster beneficial algae and improve water quality in the Tualatin River Year 3 of 3.

11. Monitor turbidity and suspended-sediment concentrations in 22,905 15,270 38,175 Chicken Creek at Roy Rogers Road.

INVESTIGATIONS SUBTOTAL $ 112,890 $ 75,260 $ 188,150

TOTAL $ 296,262 $ 197,508 $ 493,770

Enclosed is a signed Joint Funding Agreement (JFA) which is needed to continue the Tualatin River Basin Studies. If the proposed cooperative study is acceptable, please return a signed copy (a scanned electronic copy is sufficient) of the JFA to this office as soon as possible to ensure that USGS can continue to provide you with continuous data and research beyond September 30, 2020.

The work elements of this program will be conducted on a fixed-price basis. According to Bureau policy, no work may begin, and no expenses may be incurred prior to an agreement being signed by authorized officials of Clean Water Services and USGS. The signed agreement is not a bill and no funds are required at this time; rather, the agreement is our legal authority that permits the work to be done and which authorizes USGS to accept funds. The USGS Water Resources Cooperative Program operates under the authority of statute 43 USC 50, which allows us to perform this work. The Oregon Water Science Center DUNS number is 137883463.

Note that if additional work items are identified or the proposed work items are expanded during the study, section 2(d) of the JFA states that the funding agreement can be modified with a simple exchange of letters between the District and USGS. The District will be billed quarterly by DI-1040, Bill for Collection, unless a written request for a different billing cycle is received with the signed JFA. The results of all work under this agreement will be available for publication by the USGS.

During the course of this jointly planned activity and partnership, USGS may provide unpublished USGS data or information to your office for scientific peer and (or) courtesy review. -disclosure policy will be provided with any review material and is further explained in USGS Fundamental Science Practices at https://www2.usgs.gov/fsp/.

We look forward to continuing this cooperative investigation of the Tualatin River basin. If you -251-3204, or Erin Poor at 503- 251-3240 ([email protected]).

Sincerely,

James D. Crammond Center Director

Enclosures

c: Ken Williamson, District Bob Baumgartner, District Raj Kapur, District Stewart Rounds, USGS Terrence Conlon, USGS Form 9-1366 U.S. Department of the Interior Customer #: 6000000137 (May 2018) U.S. Geological Survey Agreement #: 21YFJFA00000012 Joint Funding Agreement Project #: FOR TIN #: 93-1316567 Water Resource Investigations

Fixed Cost Agreement YES[ X ] NO[ ]

THIS AGREEMENT is entered into as of October 1, 2020, by the U.S. GEOLOGICAL SURVEY, Oregon Water Science Center, UNITED STATES DEPARTMENT OF THE INTERIOR, party of the first part, and the Clean Water Services party of the second part.

1. The parties hereto agree that subject to the availability of appropriations and in accordance with their respective authorities there shall be maintained in cooperation a water resource investigation of the Tualatin River, Oregon, herein called the program. The USGS legal authority is 43 USC 36C; 43 USC 50, and 43 USC 50b.

2. The following amounts shall be contributed to cover all of the cost of the necessary field and analytical work directly related to this program. 2(b) include In-Kind-Services in the amount of $0.00

(a) $197,508 by the party of the first part during the period October 1, 2020 to September 30, 2021

(b) $296,262 by the party of the second part during the period October 1, 2020 to September 30, 2021

(c) Contributions are provided by the party of the first part through other USGS regional or national programs, in the amount of: $0

Description of the USGS regional/national program:

(d) Additional or reduced amounts by each party during the above period or succeeding periods as may be determined by mutual agreement and set forth in an exchange of letters between the parties.

(e) The performance period may be changed by mutual agreement and set forth in an exchange of letters between the parties.

3. The costs of this program may be paid by either party in conformity with the laws and regulations respectively governing each party.

4. The field and analytical work pertaining to this program shall be under the direction of or subject to periodic review by an authorized representative of the party of the first part.

5. The areas to be included in the program shall be determined by mutual agreement between the parties hereto or their authorized representatives. The methods employed in the field and office shall be those adopted by the party of the first part to insure the required standards of accuracy subject to modification by mutual agreement.

6. During the course of this program, all field and analytical work of either party pertaining to this program shall be open to the inspection of the other party, and if the work is not being carried on in a mutually satisfactory manner, either party may terminate this agreement upon 60 days written notice to the other party.

7. The original records resulting from this program will be deposited in the office of origin of those records. Upon request, copies of the original records will be provided to the office of the other party.

8. The maps, records or reports resulting from this program shall be made available to the public as promptly as possible. The maps, records or reports normally will be published by the party of the first part. However, the party of the second part reserves the right to publish the results of this program, and if already published by the party of the first part shall, upon request, be furnished by the party of the first part, at cost, impressions suitable for purposes of reproduction similar to that for which the original copy was prepared. The maps, records or reports published by either party shall contain a statement of the cooperative relations between the parties. The Parties acknowledge that scientific information and data developed as a result of the Scope of Work (SOW) are subject to applicable USGS review, approval, and release requirements, which are available on the USGS Fundamental Science Practices website (https://www.usgs.gov/about/organization/science-support/science-quality-and-integrity/fundamental-science- practices). Form 9-1366 U.S. Department of the Interior Customer #: 6000000137 (May 2018) U.S. Geological Survey Agreement #: 21YFJFA00000012 Joint Funding Agreement Project #: FOR TIN #: 93-1316567 Water Resource Investigations

9. Billing for this agreement will be rendered quarterly. Invoices not paid within 60 days from the billing date will bear Interest, Penalties, and Administrative cost at the annual rate pursuant the Debt Collection Act of 1982, (codified at 31 U.S.C. § 3717) established by the U.S. Treasury.

USGS Technical Point of Contact Customer Technical Point of Contact

Name: Erin Poor Name: Rajeev Kapur Hydrologist Water Resource Manager Address: 2130 SW 5th Avenue Address: 2550 SW Hillsboro Highway Portland, OR 97201 Hillsboro, OR 97123 Telephone: (503) 251-3240 Fax: (503) 251-3470 Telephone: (503) 681-4424 Email: [email protected] Fax: Email: [email protected]

USGS Billing Point of Contact Customer Billing Point of Contact

Name: Peter Koestner Name: Rajeev Kapur Hydrologic Technician Water Resource Manager Address: 2130 SW 5th Avenue Address: 2550 SW Hillsboro Highway Portland, OR 97201 Hillsboro, OR 97123 Telephone: (503) 251-3261 Telephone: (503) 681-4424 Fax: (503) 251-3470 Fax: Email: [email protected] Email: [email protected]

U.S. Geological Survey United States Clean Water Services Department of Interior

Signature Signatures

By______Date: ______By______Date: ______Name: James D. Crammond Name: Title: Center Director Title:

By______Date: ______Name: Title:

By______Date: ______Name: Title: Prepared by

Erin Poor

U.S. Geological Survey Oregon Water Science Center 2130 SW 5th Avenue Portland, OR 97201 [email protected] 503-251-3240

Prepared for:

Bob Baumgartner

Regulatory Affairs Department Director Clean Water Services 2550 SW Hillsboro Highway Hillsboro, OR 97123 [email protected]

Original draft: August 31, 2020 Revised/finalized: September 24, 2020

The work elements and funding for the FY 2021 Tualatin River Water-Quality Assessment Study are listed in the following table, where “District” refers to Clean Water Services. The first seven elements are basic data collection and support activities, whereas the last four elements are investigations.

WORK ELEMENT DISTRICT USGS TOTAL 1. Provide support for District laboratory in national USGS 2,130 1,420 3,550 QA programs and supply a certified chlorophyll standard. 2. Monitor air and water temperature (two sensors), pH, 38,610 25,740 64,350 specific conductance, dissolved oxygen (two sensors), turbidity, chlorophyll, phycocyanin, and barometric pressure at the Oswego Dam. 3. Monitor water temperature (two sensors), pH, specific 24,813 16,542 41,355 conductance, and dissolved oxygen (two sensors at river mile 24.5. 4. Monitor solar insolation at the Durham Treatment Facility. 5,391 3,594 8,985 5. Collect and report TVID water withdrawals at the Spring 0 0 0 Hill Pump Plant. (no charge) 6. Monitor water temperature, pH, specific conductance, 102,348 68,232 170,580 dissolved oxygen, and turbidity in four Tualatin River tributaries with the addition of fDOM, phycocyanin and chlorophyll at the Scoggins monitor 7. Assist with water-quality monitor in the Tualatin River at 10,080 6,720 16,800 Highway 219

BASIC PROGRAM SUBTOTAL $ 183,372 $ 122,248 $ 305,620 8. Import District water-sample data from 2019 and other 3,618 2,412 6,030 miscellaneous periods into the USGS NWIS database. 9. Update inputs and assumptions for Wapato Water 2,589 1,726 4,315 Management Scenario Tool and attend meetings related to the Wapato Lake NWR restoration project. 10. Provide technical expertise and monitoring to support 83,778 55,852 139,630 adaptive management at Fernhill Wetlands to foster beneficial algae and improve water quality in the Tualatin River—Year 3 of 3. 11. Monitor turbidity and suspended-sediment concentrations 22,905 15,270 38,175 in Chicken Creek at Roy Rogers Road.

INVESTIGATIONS SUBTOTAL $ 112,890 $ 75,260 $ 188,150

TOTAL $ 296,262 $ 197,508 $ 493,770

BACKGROUND / INTRODUCTION In 1988, the Tualatin River basin in northwestern Oregon (fig. 1) became the first waterbody in the United States to be regulated under the Total Maximum Daily Load provisions of the Federal Clean Water Act. A large and growing urban population contributed to eutrophication in the Tualatin River at that time. The river commonly grew large algae blooms that led to exceedances of the State of Oregon maximum pH standard (8.5 std units). The algae and high ammonia concentrations led to ammonia toxicity issues and problems with low dissolved oxygen concentrations at times. Little was known about some aspects of the river’s quality, and contentious political debates were proving detrimental to achieving progress in improving the river’s water quality. In 1990, the U.S. Geological Survey (USGS) was asked by an Oregon Congressional Representative to assist the Unified Sewerage Agency of Washington County (now Clean Water Services) to better understand the sources, transport, and fate of phosphorus and the dynamics of algal growth and water quality in the river. Clean Water Services (a.k.a. the District) is the primary wastewater treatment and stormwater management utility for most of the urban areas of the Tualatin River basin. The initial studies proved helpful by providing unbiased scientific results that could be used to better understand the system and evaluate the potential effectiveness of future management strategies. Because of that initial success, USGS and Clean Water Services have continued their scientific collaborations. Now completing its 30th full year, the USGS Tualatin River Water- Quality Assessment Study, in partnership with Clean Water Services, still provides an excellent framework for research into a wide range of water-quality issues with direct ties to resource management, such as: • techniques and instrumentation for continuous water-quality monitoring, • use of real-time water-quality monitoring for regulatory feedback and status and trends, • water-quality modeling of rivers and lakes, • measurement and causes of oxygen-consuming processes at the sediment-water interface, • dynamics and responses of plankton communities and their water-quality effects, • urban water-quality assessments, including emerging contaminants, • storm-related water-quality monitoring and research, • development of neural network modeling methods for potential water-quality forecasting, • organic-matter source assessments using stable isotope and fluorescence techniques, • assessments of ecosystem stressors to guide future monitoring and research, • development of conceptual models to communicate critical river-system concepts/processes, • assessments of the effects of beavers on the hydrology and quality of urban streams, and • monitoring and evaluation of water-quality processes in wetland-based natural treatment systems. • Measuring suspended sediment concentrations and calculating suspended sediment loads More information on completed studies and a list of USGS Tualatin River publications can be found at the project website (https://www.usgs.gov/centers/or-water/science/tualatin-river-basin- water-quality-assessment) and in Appendix 1 of this work plan.

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 3 of 31

Figure 1. Map showing the Tualatin River basin in northwestern Oregon.

The Tualatin River Water-Quality Assessment Study typically includes a strong data- collection effort in conjunction with investigations into prioritized topical areas. Roughly half the funding in past years supported a quality assurance program and continuous monitoring of water quality and selected meteorological parameters at 6-12 sites. The focus of investigations in Federal fiscal year (FY) 2021 is on (1) the third year of a study providing technical assistance and monitoring related to District operations at Fernhill Wetlands and its natural treatment system, and (2) the second year of a turbidity and suspended-sediment monitoring program in the Chicken Creek watershed.

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 4 of 31 PROBLEM In addition to managing stormwater and wastewater in the urban areas of Washington County, Oregon (fig. 1), Clean Water Services is active in managing, protecting, and restoring water quality in the streams and rivers of the Tualatin River basin. Making informed decisions about the best management actions for resource management and restoration requires knowledge, insights, data, and tools to assess and evaluate management options and optimize the expenditure of ratepayer funds on actions that work. The Fernhill Wetlands study is focused on collecting information and providing technical assistance to understand oxygen production and consumption as well as algal growth and the characteristics of the algal community in the Fernhill Wetlands natural treatment system (NTS). The operational goal is to maintain a baseline water quality and enhance the production of beneficial diatoms and green algae rather than harmful cyanobacteria, thus protecting and enhancing water quality and algal communities in downstream reaches of the Tualatin River. Other parts of the proposed work address some of the most critical ongoing data-collection needs to support the management and assessment of river quality and ecosystem health throughout the river basin. USGS will carry out much of this proposed data collection and provide other support and technical assistance, as needed.

OBJECTIVES The objectives of the proposed work are several: • To support a quality assurance program for the District water-quality laboratory, • To continuously monitor water quality at 6 baseline sites to provide data for regulatory feedback, process-based knowledge, long-term trend analysis, and other purposes, • To collect continuous solar-insolation data to support data-analysis and water-quality modeling efforts, • To import the 2019 Clean Water Services data used by USGS into NWIS, • To provide expertise and assistance related to restoration at the Wapato Lake NWR, • To provide expertise and monitoring to support operations and adaptive management at Fernhill Wetlands to foster beneficial algae and improve water quality in the Tualatin River, • To monitor turbidity and suspended-sediment concentrations in Chicken Creek at Roy Rogers Rd., • To finish up the overdue reports. The largest objectives are the basic water-quality monitoring and the data analysis and report writing for the Fernhill Wetlands study, but this list of objectives covers all the work described in this work plan.

RELEVANCE AND BENEFITS As the Nation’s leading earth science agency, USGS is proactive in ensuring that its activities are consistent with its mission and that its mission remains relevant to the Nation’s needs. USGS periodically updates a set of strategic planning documents to prioritize its core activities. The most recent Water Science Strategy (Evenson and others, 2013) outlines specific interconnected goals, objectives, and strategic actions to ensure that the scientific research and data-collection activities of the USGS address the most-important emerging water-science issues of the next 5 to 10 years.

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 5 of 31 This work plan addresses several of the strategic priorities and actions identified by Evenson and others (2013). For example, Goal 1 of the Water Science Strategy is to “provide society the information it needs regarding the amount and quality of water in all components of the water cycle at high temporal and spatial resolution, nationwide.” Under that Goal, Objective 2 is “advancement of monitoring networks and techniques for determining water-quality” and Strategic Action 5, which is to “commit to long-term data collection at a core set of nationally important surface-water-quality sites that would constitute a national surface-water-quality observation network…” The basic data-collection activities in this work plan (tasks 2-4, 6) are part of a long-term water-quality monitoring network. The Tualatin River water-quality monitors (tasks 2, 3, 6 and 7) were explicitly called out as an example of how USGS water-quality monitoring is being used for direct real-time management of water quality and regulatory feedback in the Nation’s waters (page 22 of Evenson and others, 2013). Other tasks in this work plan focus on scientific research into processes affecting aspects of water quality in the Tualatin River basin, and therefore on the availability and usability of those waters for various purposes. Goal 2 of the Water Science Strategy is to “advance understanding of processes that determine water availability.” Objective 3 under Goal 2 is to create a “comprehensive understanding of the interactions among aquatic ecosystems, hydrology, and hydrochemistry.” Directly resulting from that need, Strategic Action 11 was identified as a need to “conduct integrated research relating water availability to sustainable aquatic ecosystems, including … water quality and biogeochemistry, competing human demands, and relations to ecosystem structure and health.” Indeed, studies of algal communities in Fernhill Wetlands (task 10 of this work plan) directly address this scientific research need. Understanding how management activities at Fernhill Wetlands affect the river’s algal community is a great example of ties between water management, human influences, ecosystem structure, human health, and water availability for certain beneficial uses. Objective 4 of the Water Science Strategy expands on Goal 2 to advance our understanding of processes, calling out the need for a “comprehensive understanding of human interactions with water availability.” Strategic Action 12 addresses that need to “conduct monitoring, research, and modeling activities, in coordination with various water-related management actions, to improve understanding of benefits, limitations, and adaptive strategies.” The investigation of algal communities at Fernhill Wetlands (task 10 of this work plan) directly address this need for monitoring and research. In summary, the continuous water-quality monitoring associated with this study provides real-time information for the active management of flow and water quality in the basin. The proposed monitoring and research tasks will aid management activities to improve water quality and ecosystem health throughout the Tualatin River basin. All these activities support the USGS core mission of providing objective and reliable data and scientific information to support wise management of the Nation’s water resources. Reference Cited— Evenson, E.J., Orndorff, R.C., Blome, C.D., Böhlke, J.K., Hershberger, P.K., Langenheim, V.E., McCabe, G.J., Morlock, S.E., Reeves, H.W., Verdin, J.P., Weyers, H.S., and Wood, T.M., 2013, U.S. Geological Survey water science strategy—Observing, understanding, predicting, and delivering water science to the Nation: U.S. Geological Survey Circular 1383–G, 49 p. (Available at https://pubs.usgs.gov/circ/1383g/.)

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 6 of 31 APPROACH (WORK PLAN) In this section, eleven work elements (see list below) are described in detail. The objectives for each work element along with an approach for carrying out the work are included in each description, along with timelines and products for each. 1. Provide support for the District water-quality laboratory in national USGS Quality Assurance programs, and supply a certified chlorophyll standard. 2. Monitor air and water temperature, pH, specific conductance, dissolved oxygen (two sensors), turbidity, chlorophyll, phycocyanin, and barometric pressure at the Oswego Dam. 3. Monitor water temperature, pH, specific conductance, dissolved oxygen (two sensors), chlorophyll, and phycocyanin at river mile 24.5. 4. Monitor solar insolation at the Durham Advanced Wastewater Treatment Facility. 5. Collect and report TVID water withdrawals at the Spring Hill Pump Plant. 6. Monitor water temperature, pH, specific conductance, dissolved oxygen, and turbidity in four Tualatin River tributaries. 7. Assist with monitoring water temperature, pH, specific conductance, dissolved oxygen, and turbidity in the Tualatin River at Highway 219. 8. Import District water-sample data from 2019 and other miscellaneous periods into the USGS NWIS database. 9. Support existing water-budget tools for the Wapato Lake National Wildlife Refuge, attend meetings, and provide expertise. 10. Analyze data collected for the Fernhill study to support adaptive management at Fernhill Wetlands to foster beneficial algae and improve water quality in the Tualatin River and write a report of the findings. 11. Monitoring turbidity and suspended-sediment concentrations in Chicken Creek.

Additionally, four reports and one fact sheet have been drafted from the recent three-year study of the effects of beaver activity on the hydrology and water quality of urban streams in the Tualatin River basin. USGS commits to finishing these reports and publishing them in the 2021 fiscal year.

1. Provide support for District laboratory in national USGS QA programs, and supply a certified chlorophyll standard. Over the years, a USGS quality assurance (QA) program for the Clean Water Services (District) water-quality laboratory has helped to ensure that data produced by the District laboratory are of the highest possible quality, thus providing a reliable and accurate basis for decision making. The District laboratory currently operates a high-quality laboratory with extensive QA programs, and no longer needs the sort of detailed assistance that USGS provided in previous years. This work element provides just two services that continue to be useful to the District laboratory’s QA program: • USGS will provide the District laboratory with a USGS-certified chlorophyll-a stock solution from the USGS National Water Quality Laboratory for use in District analyses, and • Twice a year, USGS will provide the District laboratory with samples necessary for District participation in the national USGS Standard Reference Sample interlaboratory comparison program.

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 7 of 31 One primary focus for the interlaboratory comparison program is the analysis of various nitrogen and phosphorus constituents, such as orthophosphate, total phosphorus, ammonia, and nitrate. Results of the national interlaboratory comparison program and any other relevant QA programs will be discussed and coordinated between USGS and the Quality Assurance Coordinator of the District water-quality laboratory. Expenses under this and other work elements are matched on a 40:60 (USGS:District) basis. Costs for this work element are the same as last year and are fairly minimal at this point.

QA/QC SUPPORT FOR DISTRICT LAB COST USGS contribution $ 1,420 District contribution 2,130 Total $ 3,550

2. Monitor air and water temperature, pH, specific conductance, dissolved oxygen (two sensors), turbidity, chlorophyll, phycocyanin, and barometric pressure at the Oswego Dam, with near-real-time reporting. The Oswego Dam monitor provides continuous water-quality measurements in a sensitive reach of the Tualatin River at a site approximately 1.5 days travel time downstream of the Durham advanced wastewater treatment facility. The data collected at this site (water temperature (two sensors), pH, specific conductance, dissolved oxygen (two sensors), turbidity, chlorophyll, phycocyanin, barometric pressure, and air temperature) are valuable not only for determining the quality of the river in near-real-time, but also for river management via flow augmentation, for modeling efforts, for analyzing long-term trends in water quality, and for setting ammonia wasteload levels from District treatment facilities. Dissolved Oxygen. Because dissolved oxygen is a critical parameter for assessing river health, and because it is used as feedback for setting permitted ammonia effluent limits for the Durham advanced wastewater treatment facility, dissolved oxygen will be measured with two redundant sensors at this site on separate instruments. Having two measurements of dissolved oxygen provides additional quality assurance and a backup dataset in case a sensor fails. A discrepancy of more than 0.7 mg/L between the two sensors will trigger a site visit to correct for fouling, instrument drift, or other problems; typically, agreement between the two sensors is very close. Data from both sensors will be made available to the District to meet its permit needs. Both sensors will use advanced optical measurement technology. Turbidity. Continuous measurements of turbidity are important for estimating annual mass export rates of sediment from the Tualatin River basin, should that become a priority in the future. Turbidity measurements provide data and insights into the timing and relative magnitude of sediment-transport events, particularly during storms. Sediments are key to many aspects of water quality in the Tualatin River and its tributaries, particularly those aspects relating to sediment oxygen demand and dissolved oxygen. Turbidity is a somewhat-expensive parameter to measure due to the cost of the standard solutions needed to calibrate the sensor; however, the data are worth the extra incremental cost. Chlorophyll. The chlorophyll sensor will be calibrated with a stock solution of synthetic dye, as recommended by the instrument manufacturer. Samples of water near the sensor will be collected for chlorophyll-a analysis by USGS during summertime site visits to provide an independent comparison check on sensor readings.

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 8 of 31 Phycocyanin. A fluorescence sensor tuned to wavelengths needed to detect the phycocyanin pigment in blue-green algae (cyanobacteria) was installed at this site during the low-flow summer period of 2009 to 2014 to augment information collected by the chlorophyll sensor. The Tualatin River did not have large problems with blue-green algae during those years, however, and the blue-green algae sensor was removed after the 2014 season to decrease costs. The YSI EXO “total algae” sensor installed at this site in October 2016 is capable of measuring both chlorophyll and phycocyanin. Beginning in 2019, phycocyanin data are being collected with this sensor to support the Fernhill Wetlands study (see work element #11). Methods and Reporting. The Oswego Dam monitor will record data on a half-hourly basis throughout the year, although it may be necessary to remove the instruments during periods of unusually high water to protect them from damage. Measurements of chlorophyll and phycocyanin will be restricted to the summer low-flow period, approximately May 1 through mid-October. Data from this site will be transmitted to the USGS office via cellular telemetry and automatically loaded into the USGS National Water Information System (NWIS) database. All data, except for the backup dissolved oxygen and backup water temperature data, will be available to the public via a web page at https://or.water.usgs.gov/tualatin/monitors/ as well as through the USGS NWIS-Web pages at https://waterdata.usgs.gov/or/nwis/. Backup dissolved oxygen and temperature data will be available only to USGS and District personnel at a restricted-access web page at https://or.water.usgs.gov/tualatin/monitors/restricted/. Almost all water-quality sensors at this site have anti-fouling measures through the use of a brush that cleans the tip of each sensor before each measurement, thus minimizing problems associated with biological growth on the sensors. Only the specific conductance sensor is not wiped. The sensors will be cleaned and calibrated every 3-4 weeks during May through October to minimize fouling and instrument drift. During the remainder of the year, the monitor will be cleaned and calibrated every 4-5 weeks. Calibration notes will be used to correct (shift) readings between visits to ensure data accuracy. The subdaily data as well as daily summary statistics (maximum, minimum, median, mean, and running averages) will be available from the project website, from the USGS NWIS-Web system, and from the USGS Data Grapher system at https://or.water.usgs.gov/grapher/. This monitor will be operated following standard USGS procedures and protocols, most of which are documented in: Wagner, R.J., Boulger, R.W., Jr., Oblinger, C.J., and Smith, B.A., 2006, Guidelines and standard procedures for continuous water-quality monitors: station operation, record computation, and data reporting: U.S. Geological Survey Techniques and Methods Report 1-D3, 51 p. (Available at https://pubs.usgs.gov/tm/2006/tm1D3/.) The number and diversity of sensors at this site make it relatively expensive to operate, with a cost that is similar to that of operating one and a half separate monitoring sites. Costs for this work element are matched at a ratio of 40:60 (USGS:District). Costs for this work element are slightly higher compared to the previous year.

WATER-QUALITY MONITOR, OSWEGO DAM COST USGS contribution $ 25,740 District contribution $ 38,610

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 9 of 31 Total $ 64,350

3. Monitor water temperature (two sensors), pH, specific conductance and dissolved oxygen (two sensors) at river mile 24.5 of the Tualatin River, with near-real-time reporting. The Tualatin River monitor located at river mile (RM) 24.5 provides valuable data in a reach of the river that is about one and a half to two days travel time downstream of the Rock Creek advanced wastewater treatment facility’s outfall. These data are useful in determining the effect of that effluent on the river’s quality, particularly in those rare times when the Rock Creek facility might discharge higher-than-normal levels of ammonia. Episodic releases of ammonia from the Rock Creek treatment facility during the summers of 1995, 1996, and 1999 emphasize the importance of the data that are collected with this monitor. These data also are useful for future and ongoing modeling work, for decisions about flow augmentation levels, assessments of upstream algae sources (such as from Wapato Lake or Fernhill Wetlands), and as feedback for permitted ammonia effluent limits from the Rock Creek advanced wastewater treatment facility. This water-quality monitor will measure water temperature, pH, specific conductance and dissolved oxygen (two sensors) on a half-hourly basis at RM 24.5. The data will be collected with two separate multiparameter instruments as in fiscal year 2020. Dissolved Oxygen. Because dissolved oxygen is a critical parameter for assessing river health, and because it is used as feedback for setting permitted ammonia effluent limits for the Rock Creek advanced wastewater treatment facility, dissolved oxygen will be measured with two redundant sensors at this site. Having two measurements of dissolved oxygen provides additional quality assurance and a backup dataset in case a sensor fails. A discrepancy of more than 0.7 mg/L between the two sensors will trigger a site visit to correct for fouling, instrument drift, or other problems; typically, agreement between the two sensors is very close. Data from both sensors will be made available to the District to meet its permit needs. Both sensors will use advanced optical measurement technology. Methods and Reporting. Data from this site will be transmitted to the USGS office via cellular telemetry and automatically loaded into the USGS NWIS database. All data, except for the backup dissolved oxygen and backup water temperature data, will be available to the public at https://or.water.usgs.gov/tualatin/monitors/ as well as through the USGS NWIS-Web pages at https://waterdata.usgs.gov/or/nwis/. The backup dissolved oxygen and water temperature data will be available only to USGS and District personnel at a restricted-access web page at https://or.water.usgs.gov/tualatin/monitors/restricted/. Due to site-access problems under high-water conditions and the presence of debris that can jeopardize the instruments during winter, this monitor will be active only during the low-flow summer months. The monitor will be installed sometime in mid-April 2021, and will be removed sometime in November 2021, depending on flow conditions. Throughout the summer of 2021, the monitor will be cleaned and calibrated approximately every 3-4 weeks to minimize instrument drift and problems caused by biological growth on the sensors. Such biofouling can be a significant problem; cleaning and calibration visits are crucial to the collection of accurate data. Calibration notes will be used to correct (shift) readings between visits to ensure the accuracy of the final record. This monitor will be operated according to standard USGS protocols (Wagner and others, 2006). The subdaily data as well as daily summary statistics (maximum, minimum,

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 10 of 31 median, mean, and running averages) will be available from Tualatin River Basin Studies website, from the USGS NWIS-Web system, and from the USGS Data Grapher system at https://or.water.usgs.gov/grapher/. Costs for this work element are matched at a ratio of 40:60 (USGS:District). Costs for this work element are slightly higher than those from the previous year.

WATER-QUALITY MONITOR, RM 24.5 COST USGS contribution $ 16,542 District contribution 24,813 Total $ 41,355

4. Monitor solar insolation at the Durham Advanced Wastewater Treatment Facility, with near-real-time reporting. Solar insolation rates will be measured from a station on the roof of the Solids Building at the Durham advanced wastewater treatment facility. These data are useful: • as a measure of energy available for algal growth in the Tualatin River, • to determine when conditions are favorable for a significant amount of photosynthetic activity in the river, which greatly affects the river’s dissolved oxygen concentration and therefore the river’s ability to assimilate loads of ammonia and carbonaceous biochemical oxygen demand, • as an input to temperature and water-quality models of the river, as solar radiation is one of the most important heat inputs to the river, and • as an input to a potential real-time dissolved oxygen forecasting tool for the Tualatin River. Photosynthetically active radiation (PAR) will be recorded hourly (average insolation rate measured every minute for the previous hour). Two sensors will be deployed so that backup data are available should the primary sensor fail. The monitor will be operated year-round, with substitution by the backup sensor for a couple weeks in mid-winter so that each sensor in turn can be sent to the manufacturer for testing and re-certification. Data will be transmitted from the sensor with telemetry via a District telephone line. The District is responsible for the maintenance of a phone line to the rooftop location of this sensor. Data will be available to District personnel, project partners, and the public via a web page at https://or.water.usgs.gov/tualatin/monitors/, from the USGS NWIS-Web system, and from the USGS Data Grapher system at https://or.water.usgs.gov/grapher/. The solar sensors will be visited every two months for inspection, cleaning, and if necessary, manual data downloads. Daily statistics (mean, maximum, median) and hourly measurements for the final corrected, checked, and reviewed data will be available from the Tualatin River Basin Studies web site. Costs for this work element are matched at a ratio of 40:60 (USGS:District). Costs for this work element have increased slightly from the previous year.

SOLAR INSOLATION SENSORS COST USGS contribution $ 3,594

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 11 of 31 District contribution $ 5,391 Total $ 8,985

5. Collect and report TVID water withdrawals from the Spring Hill Pumping Plant. One of the largest summertime withdrawals of water from the Tualatin River takes place at the Tualatin Valley Irrigation District (TVID) Spring Hill Pumping Plant near Forest Grove (RM 56.1). To manage the water resources of the river, the Tualatin River flow management technical committee needs water withdrawal rate data from this site. These data also are used to estimate irrigation withdrawals elsewhere in the basin, and are important to modeling efforts. Prior to the summer of 2003, USGS personnel calibrated data from the TVID pumps and collected, reviewed, and finalized records for TVID withdrawals at this site. Due to changes at the Spring Hill Pumping Plant in 2003, the collection of data from this site and subsequent workup and quality assurance of these data became overly complicated. Therefore, USGS no longer calibrates the TVID pumps or reviews TVID data for accuracy. However, a data- collection system, pump measurements, and support from the Bureau of Reclamation have increased the reliability, and likely the accuracy, of these TVID withdrawal data, particularly since the spring of 2014. Due to the importance of these data, USGS will continue to collect and report these data on the Internet as long as the recording equipment functions properly and the datalogger/modem remains connected. The data should be usable for most of the purposes for which they are intended. USGS provides this reporting activity at no charge. Withdrawal data from this site will be available from the Tualatin monitors web page at https://or.water.usgs.gov/tualatin/monitors/.

REPORT TVID SPRING HILL WITHDRAWALS COST USGS contribution $ 0 District contribution 0 Total (no charge) $ 0

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 12 of 31 6. Monitor temperature, pH, specific conductance, dissolved oxygen, and turbidity in four Tualatin River tributaries with near-real-time reporting. Since 2001, USGS has used continuous multiparameter instruments to monitor water quality in the largest tributaries to the Tualatin River (Fanno, Rock, Dairy, Gales, Scoggins, Beaverton, and Chicken Creeks). These data are important for: • assessing water quality in these streams, • gaining a better understanding of processes influencing water quality in these tributaries and the important time scales and seasonal nature of those processes, • providing near-real-time notification of anomalous conditions that might require action on the part of managers or regulators, • quantifying the effects of storm runoff on water quality, • quantifying loads of sediment and other constituents, such as bacteria and phosphorus and organic matter, that can be correlated with data from these monitors, and • establishing a baseline of data that, over time, can be used to assess trends in water quality. These continuous monitors, in conjunction with the District’s routine monitoring program and the USGS Tualatin River monitors, form the foundation of a robust watershed monitoring program. Water quality was monitored by USGS at seven Tualatin River tributary sites from 2001 through 2011. Two monitors (Dairy Creek, Chicken Creek) were discontinued in 2011- 2012 after an assessment of the monitoring network. The Dairy Creek data had exhibited no trends in recent years, and the Chicken Creek site was deemed less important than the others. The Scoggins Creek site is important for capturing the quality of water released from Hagg Lake. The Gales Creek site is useful for characterizing water quality in a largely forested stream that has important and ongoing restoration activities, including flow augmentation. Rock, Beaverton, and Fanno Creeks are major urban streams feeding into the Tualatin River and are critical stream systems within the urban growth boundary and the District’s service area. In late 2015, after receiving training on USGS protocols, District staff took over the operation of the Beaverton Creek water-quality monitor and they will continue to operate that site in 2021 with a minimal amount of assistance from USGS. Given scarce monitoring resources and a need to understand the status and trends in water quality in a wide range of the basin’s streams, monitoring among these sites may be rotated, potentially reinstalling a monitor after a few years to enable longer-term trends to be captured. Alternatively, District staff may install and operate a continuous water-quality monitor at one of the discontinued sites with assistance from USGS staff. USGS will continue to work with District staff to evaluate the sites in the monitoring network and provide assistance as necessary when changes are needed. In 2021 (as in 2020), USGS will run four tributary sites and District staff will run one tributary site using USGS protocols. USGS will continue to store data from these sites in NWIS and make those data available online. In addition, the Jackson Bottom Wetlands Preserve runs a continuous water-quality monitor in the Tualatin River at Hwy 219 near Hillsboro, and USGS operates a water-quality monitor in the Tualatin River at the Dilley gage farther upstream. These monitors contribute additional data to the network. The table on the next page summarizes the proposed tributary data-collection program for 2021 as well as continuous water-quality monitoring from other work elements or from other studies, where ■ indicates the year-round monitoring funded by this work element.

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 13 of 31 ■ year-round, USGS, this task PROPOSED, 2021

■ year-round, USGS, other tasks

■ seasonal, USGS, other tasks

□ year-round, District

♦ year-round, JBWP & USGS

♦ seasonal, JBWP & USGS

– no monitor Temperature

SITE NAME STATION ID Water Temperature pH Dissolved Oxygen Specific Conductance Turbidity Chlorophyll Phycocyanin fDOM Air Barometric Pressure Tributary Monitors Scoggins Ck blw Henry Hagg Lake 14202980 ■ ■ ■ ■ ■ ■ ■ ■ – – Gales Creek at old Hwy 47 453041123065201 ■ ■ ■ ■ ■ – – ■ – – Rock Creek at Brookwood Ave 453030122560101 ■ ■ ■ ■ ■ – – – – – Fanno Creek at Durham Road 14206950 ■ ■ ■ ■ ■ – – – – – Beaverton Creek at 170th Ave 453004122510301 □ □ □ □ □ – – – – – * Dairy Creek at Hwy 8 453113123003501 – – – – – – – – – – Chicken Creek at Roy Rogers Rd 452230122512201 ■ – – – ■ – – – – – Tualatin River or Other Monitors Tualatin River at Oswego Dam 14207200 ■ ■ ■ ■ ■ ■ ■ – ■ ■ Tualatin River at RM 24.5 14206694 ■ ■ ■ ■ – ■ ■ – – – Tualatin River at Hwy 219 14206241 ♦ ♦ ♦ ♦ ♦ ♦ ♦ – – – Tualatin River at Dilley 14203500 ■ ■ – ■ ■ ■ ■ ■ – – Fernhill Wetlands at Outfall 453016123052400 ■ ■ ■ ■ ■ ■ ■ – – – * The Dairy Creek site was discontinued in 2012. Sites may be reinstalled by USGS on a rotating basis or reinstalled and operated by District staff. At each of the tributary sites proposed to be monitored year-round in this work element (■ in the table above), water-quality sensor readings will be collected on an hourly or half-hourly basis using high-quality multiparameter instruments, as in 2020. At all four tributary sites to be monitored by USGS in 2021, data will be telemetered several times each day to the USGS office, stored in the USGS National Water Information System database, and made available on the Internet on a near-real-time basis at https://or.water.usgs.gov/tualatin/monitors/ and from the USGS NWIS-Web system at https://waterdata.usgs.gov/or/nwis/. Sites will be visited for cleaning every 3-4 weeks and for calibration checks every 6-8 weeks to minimize instrument drift and problems caused by sediment and biological growth on the sensors. New pH sensor modules will be installed at all sites as the deployed sensors reach the end of their 6- to 9-month life cycle. Calibration notes will be used to correct (shift) readings between visits to ensure the accuracy of the final record according to standard USGS protocols (Wagner and others, 2006). Data will be manually downloaded from each instrument when/if telemetry is not functioning. Every effort will be made to fix any problems quickly so that reliable and accurate data are available online for all data users.

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 14 of 31 For the Beaverton Creek site operated by District staff, USGS will continue storing those data in the USGS NWIS database and serving those data online through USGS websites as long as that is still a good solution from the District’s perspective and as long as District staff continue to follow established USGS protocols. USGS staff will continue to consult with District staff and provide assistance and training as needed for the operation of the Beaverton Creek site. The datalogger and cellular modem at that site are still owned by USGS, and we will continue to keep that equipment at the site until District staff decide on a different setup; there’s no hurry to recover that equipment. All of these sites now use the latest YSI EXO multiparameter sondes, which are reliable and high-quality instruments that retain their calibration for weeks to months and have anti-fouling mechanisms (brushes and titanium sensors) that keep the sensors relatively clean. These instruments have performed well since their installation in 2014-2015, and are producing data with smaller data corrections than the previously used generation of instruments. When necessary, USGS will swap out the standard EXO temperature/conductance sensors for the new generation of wiped temperature/conductance sensors, which may help to eliminate fouling issues on the specific conductance sensor. The EXO system also offers an excellent set of advanced sensors, such as a next-generation fDOM (fluorescent dissolved organic matter) sensor that can be wiped and kept clean with the EXO2 central wiper. fDOM is an excellent surrogate for dissolved organic carbon, and such data may prove valuable for use with the EPA’s biotic ligand model for copper toxicity. The availability of advanced sensors makes the EXO system a good platform for monitoring well into the future. An fDOM sensor is currently deployed at the Gales Creek site as a demonstration project and to support and compliment the fDOM data being collected for a different study at the Tualatin River at Dilley site. Monitoring water quality in these streams year-round provides a complete dataset for (a) examining annual and seasonal patterns in dissolved oxygen and pH, both of which are good indicators of algal activity, (b) measuring seasonal variations in water temperature, which is important to endangered fish species, and (c) capturing the higher turbidity conditions associated with storms, which in winter typically account for the largest mass movements of suspended sediment and in summer are responsible for mobilizing significant amounts of oxygen- demanding materials. Real-time telemetry enhances the quality of the collected data because problems can be diagnosed and fixed in a timely fashion and with a minimum of data loss. Telemetry also provides a useful warning of potential event-related water-quality problems in the stream and in the Tualatin River downstream. These monitors have been useful in the past for providing alerts regarding potential upstream spills or unpermitted discharges. Daily summary statistics (mean, maximum, minimum, median) as well as the subdaily measure- ments for the final corrected, checked, and approved data will be available from the Tualatin River Basin Studies website at https://or.water.usgs.gov/tualatin/monitors/, from the USGS NWIS-Web system at https://waterdata.usgs.gov/or/nwis/, and from the USGS Data Grapher system at https://or.water.usgs.gov/grapher/. Costs for this work element are matched at a ratio of 40:60 (USGS:District). Despite increasing salary and equipment costs, USGS has held the line on cost increases for these monitors by increasing efficiencies wherever possible. The final cost of about $42,645 per monitor (District share: $25,587) is well within the normal range of costs for this type of monitoring, and still includes some assistance from USGS staff for the Beaverton Creek site operated by District staff. Costs for this work element are higher than costs from the previous year.

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 15 of 31 FOUR TRIBUTARY WATER-QUALITY MONITORS COST (SCOGGINS, GALES, ROCK, FANNO) USGS contribution $ 68,232 District contribution 102,348 Total $ 170,580

7. Monitor water temperature, pH, dissolved oxygen, turbidity and specific conductance at the Tualatin River at Hwy 219

Distract staff will operate the water-quality monitor in the Tualatin River at Highway 219 with minimal assistance from USGS staff. USGS will continue to store those data in the USGS NWIS database and serving those data online through USGS websites as long as District staff continue to follow established USGS protocols. USGS staff will continue to consult with District staff and provide assistance and training as needed for the operation of the Highway 219 site.

District staff will work with USGS to update the telemetry at this site to match the configuration at the other water quality sites operated by the USGS in the Tualatin Basin. Once the telemetry is updated, data from this site will be transmitted to the USGS office via cellular telemetry and automatically loaded into the USGS National Water Information System (NWIS) database. All data will be available to the public via a web page at https://or.water.usgs.gov/tualatin/monitors/ as well as through the USGS NWIS-Web pages at https://waterdata.usgs.gov/or/nwis/.

The monitor will be operated according to USGS procedures and protocols (Wagner and others, 2006). Sensors will be cleaned every 4-5 weeks (or as necessary) and calibrated every 8-10 weeks to minimize fouling and instrument drift. Readings collected by District staff during calibration and cleaning trips will be sent to USGS staff and used to correct the continuous data to ensure the data are as accurate as possible. Costs for this work element are matched at a ratio of 40:60 (USGS:District).

WATER QUALITY MONITOR AT HWY 219 COST USGS contribution $ 6,720 District contribution $ 10,080 Total $ 16,800

8. Import selected District water-sample data from 2020 and other miscellaneous periods into the USGS NWIS database. This work element is a continuation from previous years, in which USGS personnel imported District water-sample data from 1991 through 2019 into the USGS National Water Information System (NWIS) database. To keep this effort up to date, and to import a few other special project-related datasets from previous years, will take only a few days of USGS staff time. Background/Issue— NWIS is the primary USGS database of water-quality data and is one of the most valuable archives of water-quality data in the Nation. Over 90 million water-quality results from about 5 million water samples collected at hundreds of thousands of sites are stored

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 16 of 31 in NWIS. These data represent a permanent archive of water-quality data that is accessible to the public through an online interface, NWIS-Web (for Oregon data available online, see https://waterdata.usgs.gov/or/nwis/qw/). Recent upgrades include a map-based interface and other features that make target data easier to find (see https://maps.waterdata.usgs.gov/mapper/). In 2009-10, USGS developed data-import filters and programs to read District data files and reformat them for import into NWIS. USGS and District staff worked together to identify the sites, projects, and constituents to include. Data qualifiers, laboratory methods, and parameter codes were translated for import into NWIS. New sites were established in NWIS as necessary to accommodate the imported data. To date, District water-quality monitoring data from 1991-2018 have been imported into the USGS NWIS database and marked as collected and analyzed by Clean Water Services. This assures that the data used by USGS in Tualatin River basin studies will remain accessible to the public and archived in perpetuity. USGS policy generally requires that any water-quality data used in USGS studies should be stored in the NWIS database so that a permanent and accessible archive of those data remains available for future use and evaluation (U.S. Geological Survey, 2008). USGS studies in the Tualatin River basin have relied heavily on data collected and analyzed by the District. Such data include specific targeted studies resulting from USGS/District collaborations, such as the low- flow synoptic studies of Bronson and Fanno Creeks in 1996, the storm-event studies in Fanno Creek in 1998-1999, algal-growth studies in 2007-2010, and the first year of the Fernhill Wetlands study, as well as the District’s routine monitoring data, which have been used in all of the USGS modeling studies in the Tualatin River basin from 1991 through 2011 and in recent analyses of algal communities. The NWIS system allows data from agencies such as Clean Water Services to be stored in NWIS and marked as being collected and analyzed by the District. For reasons of accessibility, permanent storage, and support of completed and ongoing studies, it is desirable to import selected District water-sample data into the NWIS database. Data targeted for import include mainly the stream and treatment plant effluent data from the District’s routine monitoring program. No data from the District’s source control program are included. Parameters of interest include field parameters (water temperature, pH, conductance, dissolved oxygen, turbidity) as well as concentrations of major ions, solids, chlorophyll, nutrients (nitrogen and phosphorus species), and metals (subject to District decision). For most of these parameters, USGS has ongoing quality assurance programs with the District that provide useful measures of the high quality of District data. Pesticide and other organics data from the District are not being imported into NWIS, partly because USGS has not used such data in its studies and has not worked with the District on a pesticide quality assurance program. Tasks for 2021— In 2021, the data-import process will continue, focusing on District data from 2020 and potentially a few special project-related datasets from previous years such as the first year of the Fernhill Wetlands study. Because data-import scripts already have been developed and it is likely that a limited number of new sites will need to be established in NWIS, the data import process should be relatively straightforward. As part of this continuing work, the methods and procedures for importing District data into NWIS will be documented so that future annual data updates can continue to be accomplished with a minimum of time, effort, and expense to either the District or USGS. Costs for this work element are matched at a ratio of 40:60 (USGS:District). Costs are similar to those from the previous year.

IMPORT SELECTED DISTRICT DATA INTO THE COST USGS NWIS DATABASE

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 17 of 31 USGS contribution $ 2,412 District contribution 3,618 Total $ 6,030

Reference Cited— U.S. Geological Survey, 2008, Appropriate data storage in the National Water Information System (NWIS): Office of Water Quality Technical Memorandum 2008.05, accessed August 11, 2019, at https://water.usgs.gov/admin/memo/QW/qw08.05.html.

9. Support existing water-budget tools for the Wapato Lake NWR, attend meetings, and provide expertise. The Wapato Lake National Wildlife Refuge (NWR) is located in the upper Tualatin River basin near Gaston, Oregon. The U.S. Fish and Wildlife Service (USFWS) began implementing the preferred restoration option in 2020. Management of the Wapato Lake NWR will continue to affect the quality of water residing within and being exported from the refuge. Water exiting the refuge flows down Wapato Creek and joins the Tualatin River at river mile 60.1, just upstream of the confluence of Scoggins Creek with the Tualatin River. Water of poor quality exported from Wapato Lake can be detrimental, affecting the quality of drinking water produced by the Joint Water Commission (JWC) and potentially causing nuisance algal blooms and disrupting recreational uses many miles downstream. Releases from Wapato Lake in the summer of 2008 caused those types of downstream problems (Rounds and others, 2015), and coordinated efforts were undertaken to avoid a repeat of those conditions in 2010, 2016, and 2017. In this work element, USGS will assist the District with the following tasks: • Task 1— Attend Meetings and Provide Expertise and Coordination: USGS staff will attend any Wapato Lake coordination and planning meetings among District, JWC, and USFWS staff, to facilitate the flow of information and provide expertise when needed. In addition, USGS staff will assist with analyses, monitoring plans, and other tasks that require the expertise of USGS staff or specialized USGS datasets and tools. • Task 2- Wapato Water Management Scenario Tool (WWMST): USGS staff will assist District staff with making updates to the inputs in the WWMST to reflect improvements made to the levee and pumps. This tool will help resource managers estimate when the water level in the lake will drop to a depth sufficient to support wetland plant communities. Tasks may be slightly modified as the work progresses, in consultation with District staff, to best meet the needs and objectives of the effort. Costs for this work element are matched at a ratio of 40:60 (USGS:District) and are lower than costs for the previous year.

TECHNICAL EXPERTISE AND ASSISTANCE TO COST SUPPORT WAPATO LAKE WATER-QUALITY USGS contribution $ 1,726 District contribution $ 2,589 Total $ 4,315

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 18 of 31 References Cited— Rounds, S.A., Carpenter, K.D., Fesler, K.J., and Dorsey, J.L., 2015, Upstream factors affecting Tualatin River algae—Tracking the 2008 Anabaena algae bloom to Wapato Lake, Oregon: U.S. Geological Survey Scientific Investigations Report 2015-5178, 41 p., doi: 10.3133/sir20155178. (Available at https://doi.org/10.3133/sir20155178.) U.S. Fish and Wildlife Service, 2017, Wapato Lake National Wildlife Refuge, Draft Environmental Assessment. Washington and Yamhill Counties, Oregon: U.S. Fish and Wildlife Service, 83 p. (Available at https://www.fws.gov/WorkArea/DownloadAsset.aspx?id=2147602804.)

10. Provide technical expertise and monitoring to support adaptive management at Fernhill Wetlands to foster beneficial algae and improve water quality in the Tualatin River—Year 3 of 3 Background and Context Substantial improvements and changes have been made at Fernhill Wetlands adjacent to and south of the Forest Grove wastewater treatment facility (WWTF), including the construction of an engineered nitrification system upstream of a wetland-based natural treatment system (NTS). These systems were designed to further treat effluent from the Forest Grove and Hillsboro West WWTFs, using natural processes and native aquatic and wetland vegetation to remove nutrients from the effluent prior to discharging the polished water to the Tualatin River just downstream of Fern Hill Road. After extensive testing and monitoring of the Fernhill Wetlands treatment system in 2016-17, the District has been moving towards full utilization of the NTS to handle Forest Grove and Hillsboro West WWTF effluent, with discharge to the Tualatin River. Wetland- polished effluent was discharged to the river at times during summer 2018, but some effluent was still diverted to the Rock Creek WWTF. In 2019, a mechanical aerator was added to the NTS outlet control structure to improve dissolved-oxygen concentrations. The enhanced Fernhill Wetlands and NTS are a great addition to District treatment systems, providing additional flexibility in handling and treating Forest Grove and Hillsboro West WWTF effluent in summer, decreasing summer influent loads to the Rock Creek WWTF (thus allowing that capacity to address current and future growth), enhancing the ability to trade effluent among District WWTFs, growing District expertise, and taking advantage of natural treatment processes and systems that have multiple benefits for District customers and the public. In discharging water from natural treatment wetlands in summer at a location relatively far upstream in the Tualatin River system (approx. river mile 55.2), the District recognizes that downstream water-quality problems could occur or be exacerbated if NTS discharges contained elevated nutrient concentrations or significant populations of zooplankton or a potentially harmful algal species. On the other hand, discharges of low nutrient concentrations or populations of beneficial algal species at that location could greatly enhance downstream water quality and the ecology of the Tualatin River. Water quality in the lower Tualatin River is a complex interplay of many linked processes and sources. Dissolved-oxygen concentrations are a good indicator of one aspect of water quality in that reach, and research has shown that photosynthesis by algae is needed to offset oxygen demands from the decomposition of organic matter in the river’s fine sediments (Rounds and Wood, 2001; Rounds and others, 1999). The Tualatin River’s plankton community, however, is complex, variable, and composed of many different species, with 143 algal taxa and 99 zooplankton taxa identified in a 2006-08 study (Carpenter and Rounds, 2013). The algal community includes both “beneficial” algae as well as potentially “harmful” blue-green algae

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 19 of 31 (cyanobacteria) that can produce a variety of toxins. That study found that the river’s algal species composition and abundance varies over the summer in response to factors such as light, nutrient levels, flow (residence time), turbidity, and the source of water (natural flow, treated effluent, reservoir releases). Decreases in natural sources of Tualatin River flow were found to be highly correlated with decreases in beneficial diatoms, decreased concentrations of chlorophyll in the lower river, and decreased rates of photosynthetic production of oxygen. Greater reservoir releases from Hagg Lake and Barney Reservoir can dilute native algal “innocula” in upstream river reaches, which propagates downstream to result in lower algal populations and decreased photosynthetic oxygen production. In addition, harmful blue-green algal blooms in the lower river can be initiated from upstream sources. Well-documented discharges of high nutrient concentrations, harmful blue-green algae (Dolichospermum [previously known as Anabaena flos-aquae]), and large populations of zooplankton from Wapato Lake in June and July of 2008 had a critically negative effect on water quality in the lower Tualatin River, resulting in a public health advisory that closed the river to recreation for 2 weeks in July (Rounds and others, 2015). The NTS at Fernhill Wetlands includes a 20-acre lake, where growths of cyanobacteria including Microcystis and Aphanizomenon were identified in 2018, 2019 and 2020. While surface scums of cyanobacteria can be hazardous for birds and other wildlife, no harmful effects were observed in 2018, possibly due to the shallow depth of the lake and wind conditions that can break up a surface scum. Problem and Objectives The amount and type of algae in the Tualatin River affect the river’s water quality and ecological health, as well as its value as a recreational resource. As a relatively new source of summertime flow to the upper Tualatin River, discharges from the Fernhill NTS have the potential to enhance or degrade downstream water quality. Discharges of low nutrient concentrations and a dose of beneficial algae could enhance downstream river conditions, but releasing an innocula of cyanobacteria also could initiate a harmful algal bloom downstream. Use of the NTS, therefore, represents an opportunity to improve and manage algal conditions and the ecology of the Tualatin River, above and beyond the avoidance of releasing any potentially harmful discharges. During these early years of operation of the Fernhill Wetlands NTS and its 20-acre lake, monitoring of algae in the wetlands, its discharges, and the downstream river is helping to better understand the effects of wetland operations and how wetland processes, throughput, residence time, wetland plant species, and other factors and treatments affect the quality and algal species composition in wetland discharges. The objectives of this study are to: • Identify and document the composition and size of the algal community in the Fernhill Wetlands NTS over a range of summertime conditions, as well as any changes to the downstream algal community that result from NTS discharges, and • Assist District staff in understanding dissolved-oxygen budgets in the NTS, identifying threats to water quality and the algal community in the NTS and downstream in the Tualatin River, and provide technical expertise to help District staff find solutions and adapt NTS operations to avoid such threats and optimize the production of beneficial algal populations in NTS discharges.

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 20 of 31 Approach All the data collection for this project will be completed at the end of FY 20, so the tasks in FY 21 will focus on data analysis and communication of the results from the study. The study objectives will be accomplished through two general tasks: 1) analysis of the data collected during years 1 and 2 of the study, and 2) communication of the findings from the study During the third year of the study, the data collected during years 1 and 2 will be analyzed and USGS staff will provide additional assistance on the operations manual. A publication of a peer- reviewed USGS report describing the results of the study will be provided. The individual tasks of the study are described in more detail in the following sections. Task 1—Analysis of data collected during years 1 and 2 During years 1 and 2 a large quantity of data was collected at Fernhill Wetlands and throughout the Tualatin River, downstream of the NTS. Data includes point measurements from a field sensor (water temperature, specific conductance, pH, dissolved oxygen, turbidity, chlorophyll, and phycocyanin) and water samples (nutrients and chlorophyll-a). Additionally, a subset of approximately 20 high-priority samples were collected over the May-September season and will be sent to a certified laboratory (PhycoTech, Inc.) for quantitative evaluation of plankton species composition and abundance. During year 3, the data will be compiled and analyzed. The results will be shared with District staff (see task 2).

All data collected in this study will be archived in approved USGS archives according to USGS protocols and policies. Time-series data will be analyzed and approved according to established USGS methods and stored in the USGS National Water Information System (NWIS). Datasets that do not fit into the NWIS framework will be archived elsewhere, such as in the online Science Base system. All results will be made available to the public.

Task 2—Communicating the findings from the study The data, information, and insights gathered during this study will provide a valuable means of understanding water quality and the characteristics and responses of the NTS algal community to various factors. Results from this study will be shared with District staff in a summary meeting. Additionally, results of the study will be described in the publication of a peer-reviewed USGS report.

In addition to the peer-reviewed publication, a separate document or informal report will be written and shared with (and possibly co-authored by) District staff, in which the results and insights from the study are discussed, and insights specific to the operation and management of Fernhill Wetlands are shared. This document is meant to help District staff optimize the operations of the wetlands and the NTS, and assist them in creating or refining their operations and management plans for those systems. District staff need an “operations manual” for the NTS that includes certain “recipes” or treatments that are targeted to achieve certain beneficial responses in the system. This informal report will either be part of that operations manual or a helpful adjunct for it.

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 21 of 31 Costs for year 3 of this work element are matched at a ratio of 40:60 (USGS:District).

TECHNICAL EXPERTISE AND MONITORING TO SUPPORT COST MANAGEMENT OF FERNHILL WETLANDS – YEAR 2 OF 3 USGS contribution $ 55,852 District contribution $83,778 Total $ 139,630

References Cited— Carpenter, K.D., and Rounds, S.A., 2013, Plankton communities and summertime declines in algal abundance associated with low dissolved oxygen in the Tualatin River, Oregon: U.S. Geological Survey Scientific Investigations Report 2013–5037, 76 p. (Available at https://pubs.usgs.gov/sir/2013/5037/.) Rounds, S.A., Carpenter, K.D., Fesler, K.J., and Dorsey, J.L., 2015, Upstream factors affecting Tualatin River algae—Tracking the 2008 Anabaena algae bloom to Wapato Lake, Oregon: U.S. Geological Survey Scientific Investigations Report 2015–5178, 41 p., doi: 10.3133/sir20155178. (Available at https://doi.org/10.3133/sir20155178.) Rounds, S.A., and Wood, T.M., 2001, Modeling water quality in the Tualatin River, Oregon, 1991–1997: U.S. Geological Survey Water-Resources Investigations Report 01-4041, 53 p. (Available at https://pubs.er.usgs.gov/publication/wri014041.) Rounds, S.A., Wood, T.M., and Lynch, D.D., 1999, Modeling discharge, temperature, and water quality in the Tualatin River, Oregon: U.S. Geological Survey Water-Supply Paper 2465-B, 121 p. (Available at https://pubs.er.usgs.gov/publication/wsp2465B.) Wagner, R.J., Boulger, R.W., Jr., Oblinger, C.J., and Smith, B.A., 2006, Guidelines and standard procedures for continuous water-quality monitors: station operation, record computation, and data reporting: U.S. Geological Survey Techniques and Methods Report 1-D3, 51 p. (Available at https://pubs.usgs.gov/tm/2006/tm1D3/.)

11. Monitor turbidity and suspended-sediment concentrations in Chicken Creek. Development and urbanization can fundamentally alter local hydrologic processes, often resulting in degraded stream systems. One of the most commonly cited changes caused by urbanization is an increase in impermeable surface area and an associated decrease in infiltration capacity, leading to faster routing of water to streams and higher peak streamflows, and culminating in greater stream power compared to pre-development conditions. Elevated stream power increases erosive forces that result in greater rates of channel incision, bank erosion, and bank failure, all of which tend to increase suspended-sediment transport in the silt-bottomed streams of the Tualatin River basin. The Chicken Creek watershed includes Urban Reserve areas and areas in and around Sherwood that have been developed intensively over the last 20 years; therefore, additional dense urban development is likely in the near future. Parts of the Chicken Creek drainage are still rural, but the Cedar Creek tributary to Chicken Creek includes areas of Sherwood that are already densely developed or will be in the future. Chicken Creek is not yet as flashy as some other urban streams in the Tualatin River basin, such as Fanno Creek. As increased development occurs in the Chicken Creek drainage, it is important to understand the factors controlling stream power and sediment transport, so that priorities for restoration and mitigation can be optimized. An analysis of suspended sediment transport is an excellent marker for stream power, and an evaluation of management options to address stream

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 22 of 31 power, erosion, and suspended-sediment transport will need to rely on measurements of suspended-sediment transport and fluxes in these stream systems. In addition, the Chicken Creek channel is being restored where it traverses the Tualatin River National Wildlife Refuge (NWR) between Roy Rogers Road and the Tualatin River (see map below). The channel that was straightened over a hundred years ago will be abandoned in favor of a restored historical and meandering channel. Clean Water Services is assisting the U.S. Fish and Wildlife Service with the restoration, and is interested in how the decreased slope of the restored channel will decrease stream power, affect sediment deposition, and affect the potential number of beaver dams that might be built and that might persist through high-flow conditions.

straightened channel straightened

monitoring site at Roy Rogers Road

Approach Task 1—Monitor turbidity and suspended-sediment concentrations in Chicken Creek at Roy Rogers Road In this work element suspended-sediment concentrations and fluxes will be measured and calculated in Chicken Creek at Roy Rogers Road, a site near its mouth but upstream of the Tualatin River NWR where the Chicken Creek channel is being restored. The Roy Rogers Road site already has a streamflow gage operated by West Consultants and funded by the District. This data has been made available on the USGS Tualatin Monitors page (https://or.water.usgs.gov/tualatin/monitors/monitors_nomap.html#chicken).

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 23 of 31 During the fall of 2019, USGS staff installed a state-of-the-science YSI EXO multiparameter instrument with water temperature and turbidity sensors. The plan is to operate the site through at least three winters, or longer, so that a sufficient number of paired turbidity, suspended-sediment concentration, and streamflow measurements can be obtained to support sediment flux calculations. Turbidity is an excellent surrogate for suspended-sediment concentration in streams (Rasmussen and others, 2009). Combined with water-sample collection for suspended-sediment concentration (SSC) analysis over a range of streamflow conditions, simple regression models of SSC as a function of turbidity can be built and used to estimate a time-series of SSC based on a measured time-series of turbidity. In this way, continuous SSC values and fluxes can be calculated and used to quantify suspended-sediment transport (and trapping) in stream reaches. Roughly 5 SSC samples will be collected over a range of conditions during the winter of 2020-21 (and again during the winter of 2021-22) to support regression models of SSC based on turbidity. Streamflow data from Chicken Creek at Roy Rogers Road will be used in conjunction with the turbidity and SSC data to estimate fluxes of suspended sediment at that site. Comparisons to a more-flashy urban stream (Fanno Creek) will be made, as a useful context.

Costs for this work element for one monitoring site on Chicken Creek are matched at a ratio of 40:60 (USGS:District). These costs assume that the District will continue to fund their consultant to measure streamflow in Chicken Creek at Roy Rogers Road. Costs for continued monitoring and monitoring at additional sites in future years will be determined next year when continuing work plans are developed in consultation with District staff.

CHICKEN CREEK TURBIDITY AND SUSPENDED SEDIMENT COST MONITORING, AND STREAM POWER ANALYSIS USGS contribution $ 15,270 District contribution $ 22,905 Total $ 38,175

References Cited— Rasmussen, P.P., Gray, J.R., Glysson, G.D., and Ziegler, A.C., 2009, Guidelines and procedures for computing time-series suspended-sediment concentrations and loads from in-stream turbidity-sensor and streamflow data: U.S. Geological Survey Techniques and Methods book 3, chap. C4, 53 p. (Available at: https://pubs.usgs.gov/tm/tm3c4/) Wagner, R.J., Boulger, R.W., Jr., Oblinger, C.J., and Smith, B.A., 2006, Guidelines and standard procedures for continuous water-quality monitors: station operation, record computation, and data reporting: U.S. Geological Survey Techniques and Methods Report 1-D3, 51 p. (Available at https://pubs.usgs.gov/tm/2006/tm1D3/.)

QUALITY ASSURANCE / QUALITY CONTROL AND DATA MANAGEMENT Several types of datasets will be produced during the proposed studies. All data will be archived and managed according to USGS protocols and policies. All data used and generated in the proposed studies will be archived and documented using existing USGS databases and

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 24 of 31 structures such as the National Water Information System or the National Spatial Data Infrastructure; therefore, nothing special above and beyond the requirements of those systems should be needed. Nevertheless, project managers will be cognizant of and follow the requirements of USGS Scientific Data Management policies and requirements contained in USGS Survey Manual section 502.6 (USGS, 2017). Continuous water-quality records will be collected and processed following procedures established by Wagner and others (2006). All continuous data will be checked, reviewed, and approved at approximately quarterly intervals according to USGS Continuous Records Processing policy (USGS, 2010). All such data will be made available to the public via NWIS- Web (https://waterdata.usgs.gov/or/nwis/) as well as the USGS Data Grapher system (https://or.water.usgs.gov/grapher/) and any special project web pages (https://or.water.usgs.gov/tualatin/monitors/). Spatial datasets such as maps and other spatial datasets will be documented with all appropriate metadata and made available through the USGS node of the National Spatial Data Infrastructure (NSDI) (see https://water.usgs.gov/lookup/getgislist) or other required outlets for the national Open Data Initiative. Models used in this study will be documented and archived according to USGS policy (USGS, 2014) and a copy maintained in the model archive of the USGS Oregon Water Science Center. A copy of the model archive for any such models will be made available to the public associated with any final peer-reviewed publications that make use of those models, according to USGS policy. Use of current and historic water-sample data results from Clean Water Services will occur only after the now-routine assessment and quality assurance of those data (see work elements #1 and #9). Such historical data have been reviewed for accuracy and appropriateness over the many years of USGS collaboration with Clean Water Services. Their water-quality laboratory has an enviable record of performance in the USGS Standard Reference Sample program as well as other interlaboratory comparison and benchmark studies. The Clean Water Services water- quality laboratory has been used in similar USGS studies in the Tualatin River basin, and an existing laboratory evaluation package will be updated accordingly. Staff obtaining water and sediment samples during the proposed studies will collect those samples in accordance with established USGS protocols, such as those documented in the USGS National Field Manual (USGS, variously dated) or documented in published NAWQA protocols (USGS, 2019). An appropriate percentage (around 20%) of samples will consist of blanks (lab blanks, field blanks, travel blanks), duplicate split samples, and where appropriate, spiked samples. In addition, USGS staff will follow up with laboratory staff to obtain QA information from the laboratory analyses to check for the presence of any problems during analysis. The quality assurance data will be analyzed to ensure that the quality of the data is sufficient for their intended uses. References Cited— U.S. Geological Survey, variously dated, National field manual for the collection of water-quality data: U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chaps. A1-A10, available online at https://pubs.water.usgs.gov/twri9A. U.S. Geological Survey, 2010, WRD Policy Numbered Memorandum 2010.02—Continuous records processing of all water time series data: accessed August 8, 2019 at https://water.usgs.gov/admin/memo/policy/wrdpolicy10.02.html.

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 25 of 31 U.S. Geological Survey, 2014, Office of Water Quality Technical Memorandum 2015.01—Policy and guidelines for archival of surface-water, groundwater, and water-quality model applications: accessed August 8, 2019 at https://water.usgs.gov/admin/memo/QW/qw2015.01.pdf. U.S. Geological Survey, 2017, U.S. Geological Survey Manual Chapter 502.6—Fundamental Science Practices—Scientific Data Management, accessed August 8, 2019 at https://www.usgs.gov/about/organization/science-support/survey-manual/5026-fundamental-science- practices-scientific-data U.S. Geological Survey, 2019, National water quality project sampling methods: accessed August 8, 2019 at https://www.usgs.gov/mission-areas/water-resources/science/national-water-quality-project-sampling- methods Wagner, R.J., Boulger, R.W., Jr., Oblinger, C.J., and Smith, B.A., 2006, Guidelines and standard procedures for continuous water-quality monitors: station operation, record computation, and data reporting: U.S. Geological Survey Techniques and Methods Report 1-D3, 51 p. (Available at https://pubs.usgs.gov/tm/2006/tm1D3/.)

PRODUCTS The proposed work elements include several types of products, from quality assured and approved datasets to peer-reviewed reports. Datasets will be archived and made available primarily in NWIS. Each work element described in the Approach section includes a discussion of any products associated with that work. A list of reports from previous Tualatin River Basin Studies programs is provided in Appendix 1.

TIMELINES All work described in this work plan (and year 3 of multi-year studies) will be carried out in Federal fiscal year 2021. Most of the work, such as the continuous water-quality and solar insolation monitoring, is ongoing throughout the year, and data will be approved in approximately 3-month intervals according to USGS Continuous Records Processing policy. Data imports to NWIS in typically occur in the fourth quarter of the fiscal year.

The results from the Fernhill Wetlands study will be presented to district staff sometime in the summer of 2021. The Chicken Creek turbidity and suspended-sediment monitoring will continue throughout the year, on a more limited basis than the previous year (5 SSC samples will be collected during the winter of 2020-21).

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 26 of 31 PERSONNEL For all funded work elements, 15 or more different staff members will be involved in the collection, checking, and review/approval of data as well as various aspects of analysis and creation of products. The staffing matrix can be summarized as follows:

NUMBER OF FUNDED WORK DAYS

HYDROLOGIST SENIOR WORK ELEMENT TECHNICIAN / ECOLOGIST HYDROLOGIST 1. QA program for District lab 1.1 2.8 0 2. Oswego Dam monitor 75 7.4 0 3. RM 24.5 monitor 52 4.0 0 4. Solar insolation monitor 6.0 0 0.6 5. TVID Spring Hill Pump data — — — 6. Four tributary monitors 162 37 0 7. Hwy 219 WQ monitor 15.5 1 — 8. District data import to NWIS 1.7 3.7 0 9. Wapato Lake assistance — 1.0 1 10. Fernhill Wetlands assistance and monitoring 40 20 80 11. Chicken Creek turbidity and SSC monitoring, and 8 25 8 stream power and beaver-dam analyses 12. Complete reports — — — Totals 361.3 101.9 89.6

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 27 of 31 Appendix 1—Published Reports from Tualatin River Basin Studies Sobieszczyk, S., Jones, K.L., Rounds, S.A., Nilsen, E.B., and Morace, J.L., 2018, Prioritization framework for ranking riverine ecosystem stressors using example sites from the Tualatin River Basin, Oregon: U.S. Geological Survey Scientific Investigations Report 2018-5153, 40 p., doi: 10.3133/sir20185153 (Available at https://doi.org/10.3133/sir20185153.) Rounds, S.A., Carpenter, K.D., Fesler, K.J., and Dorsey, J.L., 2015, Upstream factors affecting Tualatin River algae—Tracking the 2008 Anabaena algae bloom to Wapato Lake, Oregon: U.S. Geological Survey Scientific Investigations Report 2015-5178, 41 p., doi: 10.3133/sir20155178. (Available at https://doi.org/10.3133/sir20155178.) Sobieszczyk, Steven, Keith, M.K., Goldman, J.H., and Rounds, S.A., 2015, Organic Matters—Investigating the sources, transport, and fate of organic matter in Fanno Creek, Oregon: U.S. Geological Survey Fact Sheet 2015-3003, 4 p., doi: 10.3133/fs20153003. (Available at https://doi.org/10.3133/fs20153003 and https://or.water.usgs.gov/tualatin/Fanno_OM_Summary.pdf.) Sobieszczyk, Steven, Keith, M.K., Rounds, S.A., and Goldman, J.H., 2014, Investigating organic matter in Fanno Creek, Oregon, Part 1 of 3— Estimating annual foliar biomass for a deciduous-dominant urban riparian corridor: J. Hydrol., vol. 519D, 3001-3009, doi: 10.1016/j.jhydrol.2014.06.054. (Available at https://doi.org/10.1016/j.jhydrol.2014.06.054 and https://or.water.usgs.gov/tualatin/Fanno_OM_Summary.pdf.) Keith, M.K., Sobieszczyk, Steven, Goldman, J.H.,, and Rounds, S.A., 2014, Investigating organic matter in Fanno Creek, Oregon, Part 2 of 3— Sources, sinks, and transport of organic matter with fine sediment: J. Hydrol., vol. 519D, 3010-3027, doi: 10.1016/j.jhydrol.2014.07.027. (Available at https://doi.org/10.1016/j.jhydrol.2014.07.027 and https://or.water.usgs.gov/tualatin/Fanno_OM_Summary.pdf.) Goldman, J.H., Rounds, S.A., Keith, M.K., and Sobieszczyk, Steven, 2014, Investigating organic matter in Fanno Creek, Oregon, Part 3 of 3— Identifying and quantifying sources of organic matter to an urban stream: J. Hydrol., vol. 519D, 3028-3041, doi: 10.1016/j.jhydrol.2014.07.033. (Available at https://doi.org/10.1016/j.jhydrol.2014.07.033.) and https://or.water.usgs.gov/tualatin/Fanno_OM_Summary.pdf.) Carpenter, K.D., and Rounds, S.A., 2013, Plankton communities and summertime declines in algal abundance associated with low dissolved oxygen in the Tualatin River, Oregon: U.S. Geological Survey Scientific Investigations Report 2013-5037, 78 p. (Available at https://pubs.usgs.gov/sir/2013/5037/.) Goldman, J.H., Rounds, S.A., and Needoba, J.A., 2012, Applications of fluorescence spectroscopy for predicting percent wastewater in an urban stream: Environ. Sci. Technol., vol. 46, no. 8, 4374–4381, doi: 10.1021/es2041114. (Available at https://doi.org/10.1021/es2041114.) Bonn, B.A., and Rounds, S.A., 2010, Use of stable isotopes of carbon and nitrogen to identify sources of organic matter to bed sediments of the Tualatin River, Oregon: U.S. Geological Survey Scientific Investigations Report 2010–5154, 58 p. (Available at https://pubs.usgs.gov/sir/2010/5154/.) Anderson, C.W., and Rounds, S.A., 2010, Use of continuous monitors and autosamplers to predict unmeasured water-quality constituents in tributaries of the Tualatin River, Oregon: U.S. Geological Survey Scientific Investigations Report 2010–5008, 76 p. (Available at https://pubs.usgs.gov/sir/2010/5008/.) Ulrich, E.M., Foreman, W.T., Van Metre, P.C., Wilson, J.T., and Rounds, S.A., 2009, Enantiomer fractions of chlordane components in sediment from U.S. Geological Survey sites in lakes and rivers: Sci. Tot. Environ., v. 407, no. 22, 5884-5893, doi: 10.1016/j.scitotenv.2009.08.023 (Available at https://doi.org/10.1016/j.scitotenv.2009.08.023.)

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 28 of 31 Rounds, S.A., Doyle, M.C., Edwards, P.M., and Furlong, E.T., 2009, Reconnaissance of pharmaceutical chemicals in urban streams of the Tualatin River basin, Oregon, 2002: U.S. Geological Survey Scientific Investigations Report 2009–5119, 22 p. (Available at https://pubs.usgs.gov/sir/2009/5119/.) Sullivan, A.B. and Rounds, S.A., 2006, Modeling water-quality effects of structural and operational changes to Scoggins Dam and Henry Hagg Lake, Oregon: U.S. Geological Survey Scientific Investigations Report 2006–5060, 36 p. (Available at https://pubs.usgs.gov/sir/2006/5060/.) Rounds, S.A. and Sullivan, A.B., 2006, Development and use of new routines in CE-QUAL-W2 to blend water from multiple reservoir outlets to meet downstream temperature targets, in Proceedings of the Third Federal Interagency Hydrologic Modeling Conference, April 2-6, 2006, Reno, NV: Subcommittee on Hydrology of the Interagency Advisory Committee on Water Information, ISBN 0-9779007-0-3. (Available at https://or.water.usgs.gov/tualatin/fihmc3_w2_modifications.pdf.) Johnston, M.W., and Williams, J.S., 2006, Field comparison of optical and Clark cell dissolved oxygen sensors in the Tualatin River, Oregon, 2005: U.S. Geological Survey Open-File Report 2006–1047, 11 p. (Available at https://pubs.usgs.gov/of/2006/1047/.) Sullivan, A.B. and Rounds, S.A., 2005, Modeling hydrodynamics, temperature and water quality in Henry Hagg Lake, Oregon, 2000-2003: U.S. Geological Survey Scientific Investigations Report 2004–5261, 38 p. (Available at https://pubs.usgs.gov/sir/2004/5261/.) Doyle, M.C. and Rounds, S.A., 2003, The effect of chamber mixing velocity on bias in measurement of sediment oxygen demand rates in the Tualatin River basin, Oregon: U.S. Geological Survey Water- Resources Investigations Report 03–4097, 16 p. (Available at https://pubs.er.usgs.gov/publication/wri034097.) Anderson, C.W. and Rounds, S.A., 2003, Phosphorus and E. coli and their relation to selected constituents during storm runoff conditions in Fanno Creek, Oregon, 1998-99: U.S. Geological Survey Water- Resources Investigations Report 02–4232, 34 p. (Available at https://pubs.er.usgs.gov/publication/wri024232.) Rounds, S.A., 2002, Development of a neural network model for dissolved oxygen in the Tualatin River, Oregon, in Proceedings of the Second Federal Interagency Hydrologic Modeling Conference, July 29 - August 1, 2002, Las Vegas, NV: Subcommittee on Hydrology of the Interagency Advisory Committee on Water Information. (Available at https://or.water.usgs.gov/tualatin/ann_proceedings.pdf.) Rounds, S.A., 2001, Modeling water quality in the Tualatin River: Achievements and limitations, in AWRA Annual Spring Specialty Conference Proceedings, “Water Quality Monitoring and Modeling,” Warwick, John J. (ed.), American Water Resources Association, Middleburg, Virginia, TPS-01-1, p. 115-120. (Available at https://or.water.usgs.gov/tualatin/model_achievements.pdf.) Rounds, S.A. and Wood, T.M., 2001, Modeling water quality in the Tualatin River, Oregon, 1991-1997: U.S. Geological Survey Water-Resources Investigations Report 01–4041, 53 p. (Available at https://pubs.er.usgs.gov/publication/wri014041.) McCarthy, K.A., 2000, Phosphorus and E. coli in the Fanno and Bronson Creek subbasins of the Tualatin River basin, Oregon, during summer low-flow conditions, 1996: U.S. Geological Survey Water- Resources Investigations Report 00–4062, 31 p. (Available at https://pubs.er.usgs.gov/publication/wri004062.) Risley, J.C., 2000, Effects of hypothetical management scenarios on water temperatures in the Tualatin River, Oregon: U.S. Geological Survey Water-Resources Investigations Report 00-4071 (supplement to Water- Resources Investigations Report 97–4071), 110 p. (Available at https://pubs.er.usgs.gov/publication/wri004071.)

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 29 of 31 Kelly, V.J., Lynch, D.D., and Rounds, S.A., 1999, Sources and transport of phosphorus and nitrogen during low-flow conditions in the Tualatin River, Oregon, 1991-1993: U.S. Geological Survey Water-Supply Paper 2465-C, 94 p. (Available at https://pubs.er.usgs.gov/publication/wsp2465C.) Rounds, S.A., 1999, Investigations of water quality in the Tualatin River basin, Oregon, and their role in the TMDL process, in Proceedings of the Seventh Biennial Watershed Management Conference, C.W. Slaughter (ed.), Water Resources Center Report No. 98, University of California, Davis, p. 7-19. (Available at https://or.water.usgs.gov/tualatin/wmc_proceedings.pdf.) Rounds, S.A., Wood, T.M., and Lynch, D.D., 1999, Modeling discharge, temperature, and water quality in the Tualatin River, Oregon: U.S. Geological Survey Water-Supply Paper 2465-B, 121 p. (Available at https://pubs.er.usgs.gov/publication/wsp2465B.) Bonn, B.A., 1999, Selected elements and organic chemicals in bed sediment and fish tissue of the Tualatin River basin, Oregon, 1992-96: U.S. Geological Survey Water-Resources Investigations Report 99–4107, 61 p. (Available at https://pubs.er.usgs.gov/publication/wri994107.) Rounds, S.A. and Wood, T.M., 1998, Using CE-QUAL-W2 to assess the ammonia assimilative capacity of the Tualatin River, Oregon, in Proceedings of the First Federal Interagency Hydrologic Modeling Conference, Las Vegas, Nevada, April 19-23, 1998: U.S. Geological Survey, p. 2-133 - 2-140. (Available on request.) Wood, T.M. and Rounds, S.A., 1998, Using CE-QUAL-W2 to assess the effect of reduced phosphorus loads on chlorophyll-a and dissolved oxygen in the Tualatin River, Oregon, in Proceedings of the First Federal Interagency Hydrologic Modeling Conference, Las Vegas, Nevada, April 19-23, 1998: U.S. Geological Survey, p. 2-149 - 2-156. (Available on request.) Kelly, V.J., 1997, Dissolved oxygen in the Tualatin River, Oregon, during winter flow conditions, 1991 and 1992: U.S. Geological Survey Water-Supply Paper 2465-A, 68 p. (Available at https://pubs.er.usgs.gov/publication/wsp2465A.) Rounds, S.A. and Doyle, M.C., 1997, Sediment oxygen demand in the Tualatin River basin, Oregon, 1992- 1996: U.S. Geological Survey Water-Resources Investigations Report 97–4103, 19 p. (Available at https://pubs.er.usgs.gov/publication/wri974103.) Risley, J.C., 1997, Relations of Tualatin River water temperatures to natural and human-caused factors: U.S. Geological Survey Water-Resources Investigations Report 97–4071, 143 p. (Available at https://pubs.er.usgs.gov/publication/wri974071.) Risley, J.C. and Doyle, M.C., 1997, Water-temperature, specific-conductance, and meteorological data for the Tualatin River basin, Oregon, 1994-95: U.S. Geological Survey Open-File Report 96–315, 124 p. (Available at https://pubs.er.usgs.gov/publication/ofr96315.) Kelly, V.J., 1997, Dissolved oxygen in the Tualatin River, Oregon, under winter low-flow conditions, November, 1992, in Laenen, A. and Dunnette, D.A. (eds.), River Quality— Dynamics and restoration: New York, CRC Press, p. 151-162. Doyle, M.C. and Caldwell, J.M., 1996, Water-quality, streamflow, and meteorological data for the Tualatin River basin, Oregon, 1991-93: U.S. Geological Survey Open-File Report 96–173, 49 p., CD-ROM (Available at https://pubs.er.usgs.gov/publication/ofr96173.)

USGS Tualatin WQ Assessment – Scope of Work: August 31, 2020 Page 30 of 31 Appendix 2—Historical Funding for Tualatin River Basin Studies The following table shows the historical funding for Tualatin River water-quality studies. The collaboration between USGS and Clean Water Services has been fruitful and long-lasting, producing 35 reports and papers over the years (see Appendix 1). Funding for Tualatin River Basin studies (1990-2021)

FISCAL CLEAN WATER SERVICES USGS FEDERAL YEAR CASH AND DIRECT SERVICES MATCHING FUNDS TOTAL 1990 $ 50,000 $ 50,000 $ 100,000 1991 200,000 200,000 400,000 1992 515,000 515,000 1,030,000 1993 406,000 406,000 812,000 1994 296,000 296,000 592,000 1995 174,800 174,800 349,600 1996 191,500 191,500 383,000 1997 126,675 126,675 253,350 1998 170,000 170,000 340,000 1999 180,050 180,050 360,100 2000 178,050 178,050 356,100 2001 201,200 201,200 402,400 2002 210,100 210,100 420,200 2003 212,000 212,000 424,000 2004 235,750 235,750 471,500 2005 250,450 250,450 500,900 2006 291,630 250,450 542,080 2007 291,600 250,450 542,050 2008 299,150 250,450 549,600 2009 322,450 322,450 644,900 2010 319,950 319,950 639,900 2011 337,250 290,400 627,650 2012 335,750 335,750 671,500 2013 347,200 281,950 629,150 2014 337,550 265,250 602,800 2015 272,400 146,800 419,200 2016 281,650 166,800 448,450 2017 329,800 185,738 515,538 2018 334,150 180,000 514,150 2019 292,850 171,200 464,050 2020 322,750 189,900 512,650 2021 296,262 197,508 493,770 Sum $ 8,609,967 $ 7,402,621 $ 16,012,588 Average $ 269,061 $ 231,332 $ 500,393

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