Clackamas Basin: DEQ’s Water Quality Status and Trends Analysis for the Department of Agriculture’s Biennial Review of the Agricultural Area Rules and Plans

February 2017

Water Quality Program 700 NE Multnomah Suite #600 Portland, OR 97232 Phone: 503-229-5696 800-452-4011 Fax: 503-229-5850 Contact: Koto Kishida www.oregon.gov/DEQ

DEQ is a leader in restoring, maintaining and enhancing the quality of Oregon’s air, land and water.

Oregon Department of Environmental Quality

This report prepared by:

Oregon Department of Environmental Quality 700 NE Multnomah Ste #600 Portland, OR 97232 1-800-452-4011 www.oregon.gov/deq

Contact: Koto Kishida 503-229-6381

Documents can be provided upon request in an alternate format for individuals with disabilities or in a language other than English for people with limited English skills. To request a document in another format or language, call DEQ in Portland at 503-229-5696, or toll-free in Oregon at 1-800-452-4011, ext. 5696; or email [email protected].

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Table of Contents

Introduction ...... 2 Purpose ...... 2 Basin Contact ...... 2 Background Information ...... 2 Geographic Area for Analysis ...... 3 1. Methods ...... 5 1.1 Data Sources ...... 5 1.2 Decision Criteria ...... 5 1.3 Analysis ...... 6 2. Results ...... 8 2.1 Land Use ...... 8 2.2 Water Quality Limited Stream Segments ...... 12 2.3 E. coli ...... 13 2.4 pH ...... 13 2.5 Temperature ...... 17 2.6 Dissolved Oxygen ...... 21 3. Conclusions ...... 29 Appendix A ...... 32

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Introduction

Purpose Area rules and plans have been adopted by the Oregon Department of Agriculture (ODA) for the Clackamas Basin management area (603-095-1200-1280). Oregon statute and administrative rules require ODA to consult with the Department of Environmental Quality (DEQ) during the biennial review of Agricultural Water Quality Management Area Rules and Plans (ORS 568.930). DEQ Total Maximum Daily Load (TMDL) and Nonpoint Source (NPS) program staff conduct these reviews based on ODA’s biennial review schedule of their area rules and plans1. ODA’s Agriculture Water Quality Program is outcome based, explicitly describing prohibited conditions, similar to DEQ’s TMDL and NPS programs which explicitly define water quality targets and goals. The analysis of landscape conditions and water quality data is used for implementing these programs as well as identifying data gaps.

The purpose of this document is to present data and analysis that will help DEQ fulfill its roles in the biennial review process described in the Memorandum of Agreement between ODA and DEQ1. This document supports the following DEQ tasks identified in the MOA: • Review available data for water quality trends and whether waterbodies are achieving water quality standards and meeting TMDL agricultural load allocations • Evaluate and provide comment to ODA on the suitability of landscape conditions to achieve TMDL agricultural load allocations.

This report presents an analysis of water quality data readily accessible from public databases and available in sufficient quantity to indicate status and trends. Additional data may exist but was not readily available at the time this report was compiled. DEQ will use available water quality data to answer the following questions: • What is the status of water quality parameters downstream of agricultural land? • What is the trend in water quality at key locations downstream of agricultural land? • Are sites downstream of agricultural land meeting TMDL agricultural load allocations?

DEQ basin coordinators review pertinent information including this report as part of ODA’s biennial review. DEQ basin coordinators recommend changes and additional data and resources necessary to achieve water quality standards and meet TMDL agricultural load allocations through ODA’s survey.

Basin Contact Table 1- Basin coordinator contact information Basin Coordinator Telephone Email Karen Williams 503-229-6254 [email protected]

Background Information The TMDL (2006) includes ODA’s Clackamas water quality management area and focuses on temperature, bacteria, and mercury2. As part of the TMDL process, Oregon Department of

1 https://www.oregon.gov/ODA/shared/Documents/Publications/NaturalResources/DEQODAmoa.pdf

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Agriculture was identified as the Designated Management Agency for agricultural components of the TMDL. The Clackamas Agricultural Water Quality Management Area Plans serve as the TMDL implementation plans. Load allocations are included for temperature, bacteria, and mercury on agricultural lands (See tables 3 Clackamas AgWQ Management Area Plan and 6.3, 6.13, and 3.1, Willamette River TMDL3).

Geographic Area for Analysis The predominant land use in the Management Area is forestry, most of it occurring on federal lands in the eastern part of the Management Area. Fifty-four percent of land in the Subbasin is USFS National Forest Land. In the valley portions of the Management Area, the dominant land use is rural and agriculture. Urban and suburban areas concentrate in the lower 8 miles of the Clackamas watershed, but suburban areas have expanded in recent years in watersheds tributary to the lower Clackamas mainstem. Most of the farmland is located in the western portion of the Management Area, upstream from Oregon City and extending toward Sandy and Estacada in the Clackamas Subbasin. The Management Area also encompasses agricultural land in the middle Willamette Subbasin, near the city of Wilsonville. The majority of agricultural lands are located on rolling hills and high terraces with somewhat to well-drained soils. A portion of the agricultural land is artificially drained4.

2 https://www.oregon.gov/deq/wq/tmdls/Pages/TMDLs-Willamette-Basin.aspx

4 https://www.oregon.gov/ODA/shared/Documents/Publications/NaturalResources/ClackamasAWQMAreaPlan.pdf

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Figure 1-The Clackamas Basin Agricultural Water Quality Management area (ODA)

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1. Methods

1.1 Data Sources Analysts retrieved data from DEQ, EPA (STORET) and USGS (NWIS) databases. The time period for the query was from January 1, 2000 to January 1, 2017. Parameters included in the query were temperature, pH, dissolved oxygen, and bacteria. The data returned were evaluated for data quality. DEQ data included A and B level data determined following the DEQ’s Laboratory Quality Manual5. EPA and USGS data were included unless result comments indicated problems with the data. Recent data (after April 1, 2016) from the USGS was marked as provisional data and included in this analysis.

1.2 Decision Criteria Status and long-term trends of the data were assessed for evaluating water quality in relation to water quality standards or TMDL allocations. Figure 2 illustrates the decision process DEQ follows when evaluating data sufficiency. Stations that fit the criteria were sent to DEQ basin coordinator and the basin coordinator had an opportunity to suggest that data from additional stations be reviewed . Data from reservation lands were eliminated because these lands are not covered in the Ag WQ management plans. Dominant land use characteristics were used as a station descriptor, not a deciding factor.

5 http://www.deq.state.or.us/lab/techrpts/docs/DEQ91LAB0006QMP.pdf

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Figure 2- Monitoring station decision criteria to ensure the stations contain sufficient data to represent status and trends for the waterbody

1.3 Analysis DEQ compared pH results from both grab and continuous sample data to the water quality standard. The bacteria standard is based on the presence of E. coli compared to a single sample maximum and a geometric mean of five or more samples in a 90 day period. The temperature standard is based on the calculation of the seven day average of the daily maximum stream temperatures. Trends for pH and E. coli were assessed using Seasonal Kendall Analysis, which removes the influence of season-to-season fluctuations6. The Seasonal Kendall Analysis also indicates the statistical significance and slope of the trend.

Dissolved oxygen (DO) was assessed by comparing the concentration to the water quality standard. If the DO concentration exceeded the water quality standard, but met the criteria for percent saturation at the same time, it was considered to be in compliance with the water quality standard. These points were noted in the plots using a different color. Fish use and spawning maps7 and the DO criteria flow chart8 were

6 Statistical Methods for Water Resources, p338 7 http://www.oregon.gov/deq/Regulations/Pages/Administrative-Rules.aspx 8 http http://www.deq.state.or.us/wq/rules/div041/table21.pdf

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used to determine the applicable temperature and DO standards for the spawning and non-spawning time periods.

For temperature trend analysis, analysts used data only from stations with eight years of continuous hourly temperature data in each month during the query period. Data were not used if observations were missing for more than one day each month or if fewer than 22 hourly measurements were recorded during the day. These criteria resulted in no more than 10% missing data across each of the temporal periods of interest. Trends in the data were tested using a Mann Kendall test (Mann 1945). Trends were evaluated on the following metrics.

. Average Monthly 7-day average daily maximum . Average Monthly daily degree hours > the applicable temperature standard.

Trends are more detectable with the average monthly daily degree hours that exceed the applicable temperature standard because the metric incorporates both magnitude and duration of temperatures; the 7- day average daily maximum only incorporates the magnitude of exceedance. Fish use and spawning maps9 were used to determine the applicable temperature standards for the spawning and non-spawning time periods. Section 2.6 of this report includes graphs for stations with data that exceeded a water quality standard more than once and/or showed a positive or negative trend. When insufficient data was available, that was noted in the graphs.

Clackamas Subbasin Specific Water Standard Criteria10: • pH o pH (hydrogen ion concentration). pH values may not fall outside the following ranges: o All basin waters (except main stem and Cascade lakes): 6.5 to 8.5; o Cascade lakes above 3,000 feet altitude: 6.0 to 8.5. • Temperature (340-041-0028; Figures 340A and 340B; Table 340A o The seven-day-average maximum temperature of a stream identified as having and steelhead spawning use on subbasin maps and table may not exceed 13.0 degrees Celsius (55.4 degrees Fahrenheit) at the times indicated on these maps and tables; o The seven-day-average maximum temperature of a stream identified as having core cold water habitat use on subbasin maps may not exceed 16.0 degrees Celsius (60.8 degrees Fahrenheit); o The seven-day-average maximum temperature of a stream identified as having salmon and trout rearing and migration use on subbasin maps may not exceed 18.0 degrees Celsius (64.4 degrees Fahrenheit); o The seven-day-average maximum temperature of a stream identified as having a migration corridor use on subbasin maps and tables may not exceed 20.0 degrees Celsius (68.0 degrees Fahrenheit). • E. coli (340-041-0009): o A 90-day geometric mean of 126 E. coli organisms per 100 mL o No single sample may exceed 406 E. coli organisms per 100 mL • Dissolved Oxygen (340-041-0016); Figures 340A and 340B; Table 340A o (1) For water bodies identified as active spawning areas in the places and times indicated on the following Tables and Figures (as well as any active spawning area used by resident trout species), the following criteria apply during the applicable spawning through fry emergence periods set forth in the tables and figures and, where resident trout spawning occurs, during the time trout spawning through fry emergence occurs:

9 http://www.oregon.gov/deq/Regulations/Pages/Administrative-Rules.aspx 10 http://arcweb.sos.state.or.us/pages/rules/oars_300/oar_340/340_041.html

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o (a) The dissolved oxygen may not be less than 11.0 mg/l. However, if the minimum intergravel dissolved oxygen, measured as a spatial median, is 8.0 mg/l or greater, then the DO criterion is 9.0 mg/l; o (b) Where conditions of barometric pressure, altitude, and temperature preclude attainment of the 11.0 mg/l or 9.0 mg/l criteria, dissolved oxygen levels must not be less than 95 percent of saturation; o (2) For water bodies identified by the Department as providing cold-water aquatic life, the dissolved oxygen may not be less than 8.0 mg/l as an absolute minimum. Where conditions of barometric pressure, altitude, and temperature preclude attainment of the 8.0 mg/l, dissolved oxygen may not be less than 90 percent of saturation. At the discretion of the Department, when the Department determines that adequate information exists, the dissolved oxygen may not fall below 8.0 mg/l as a 30-day mean minimum, 6.5 mg/l as a seven-day minimum mean, and may not fall below 6.0 mg/l as an absolute minimum (Table 21); o (3) For water bodies identified by the Department as providing cool-water aquatic life, the dissolved oxygen may not be less than 6.5 mg/l as an absolute minimum. At the discretion of the Department, when the Department determines that adequate information exists, the dissolved oxygen may not fall below 6.5 mg/l as a 30-day mean minimum, 5.0 mg/l as a seven-day minimum mean, and may not fall below 4.0 mg/l as an absolute minimum (Table 21)

2. Results

2.1 Land Use Table 2. Summary table of watershed land use by station, only stations which have at least 8 years and/or recent data are included; Items are in order of decreasing %Agricultural cover. Source: 2011 NAIP Station ID Station Description Ws Area % % % % % (Km2) Urban Forest Ag Range Other 10339 Willamette River at 24054.7 5.6 52.2 21.5 17.3 3.5 Canby Ferry 11233 Clackamas River at High 2441.7 3.6 75.0 6.7 13.7 1.0 Rocks (Old Hwy 213) USGS- Clackamas River near 2441.7 3.6 75.0 6.7 13.7 1.0 14211010 Oregon City, OR 13070 Clackamas River at 1770.5 0.7 85.9 0.6 12.0 0.7 McIver Park (upper boat ramp) USGS- Clackamas River at 1770.5 0.7 85.9 0.6 12.0 0.7 14210000 Estacada, OR 14008 Clackamas River at 1539.6 0.4 87.4 0.0 11.6 0.7 Memaloose Road USGS- Clackamas River at 1539.6 0.4 87.4 0.0 11.6 0.7 14209710 Carter Bridge, near Estacada, OR

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Figure 3- Land cover and land use within the upstream catchment of monitoring stations 13070 and USGS 14210000

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Figure 4- Land cover and land use within the upstream catchment of stations 14008 and USGS 14209710

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Figure 5- Land cover and land use within the upstream catchment of monitoring stations 10339, 11233, and USGS 14211010

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2.2 Water Quality Limited Stream Segments Table 3. Summary of Integrated Report listings for parameters included in this report. Table based on the approved (and partially disapproved) 2012 Integrated Report Listings by the EPA. Waterbody Miles Pollutant Season Year Criteria Listing Status Sieben Drainage 0 to 1.8 Dissolved January 1 - May 2012 Spawning Cat 5 Ditch Oxygen 15 North Fork Deep 0 to 6.6 Dissolved October 15 - June 2012 Spawning Cat 5 Creek Oxygen 15 Tualatin River 0 to Dissolved January 1 - May 2010 Spawning Cat 5 62.6 Oxygen 15 Noyer Creek 0 to 3.5 Dissolved January 1 - June 2012 Spawning Cat 5 Oxygen 15 Rock Creek 1.4 to 6 Dissolved January 1 - May 2010 Spawning Cat 5 Oxygen 15 Clackamas River 0 to 8.1 Dissolved October 15 - May 2012 Spawning Cat 5 Oxygen 15 Unnamed 0 to 1.5 Dissolved January 1 - May 2012 Spawning Cat 5 Stream Oxygen 15 Tickle Creek 0 to 2.3 E. Coli Summer 2010 See Below Cat 4A North Fork Deep 0 to 9 E. Coli Summer 2010 See Below Cat 4A Creek Sieben Drainage 1 to 1.8 E. Coli FallWinterSpring 2010 See Below Cat 4A Ditch Sieben Drainage 0 to 1 E. Coli FallWinterSpring 2010 See Below Cat 4A Ditch Rock Creek 0 to 6.1 E. Coli FallWinterSpring 2010 See Below Cat 4A Clackamas River 0 to 15 E. Coli Summer 2010 See Below Cat 4A Molalla River 0 to 25 E. Coli FallWinterSpring 2010 See Below Cat 4A Cow Creek 0 to 2.6 E. Coli FallWinterSpring 2010 See Below Cat 4A Bargfeld Creek 0 to 2.3 E. Coli Summer 2010 See Below Cat 4A Willamette River 0 to E. Coli FallWinterSpring 2010 See Below Cat 4A 186.4 Deep Creek 1.9 to E. Coli Summer 2010 See Below Cat 4A 14.1 Nohorn Creek 0 to 1.8 Temperature September 1 - 2010 Salmon and Cat 4A June 15 steelhead spawning: 13.0 C 7DADM Eagle Creek 0 to Temperature Year Around 2010 Core cold water Cat 4A 25.4 (Non-spawning) habitat: 16.0 C 7DADM Bear Creek 0 to 4.8 Temperature Year Around 2010 Core cold water Cat 4A (Non-spawning) habitat: 16.0 C 7DADM 0 to Temperature Year Around 2010 Core cold water Cat 4A 12.2 (Non-spawning) habitat: 16.0 C 7DADM North Fork 0 to Temperature Year Around 2010 Core cold water Cat 4A

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Waterbody Miles Pollutant Season Year Criteria Listing Status Eagle Creek 13.1 (Non-spawning) habitat: 16.0 C 7DADM Eagle Creek 0 to Temperature September 1 - 2010 Salmon and Cat 4A 15.6 June 15 steelhead spawning: 13.0 C 7DADM Collawash River 0 to 7.7 Temperature September 1 - 2010 Salmon and Cat 4A June 15 steelhead spawning: 13.0 C 7DADM Fish Creek 0 to Temperature Year Around 2010 Core cold water Cat 4A 13.2 (Non-spawning) habitat: 16.0 C 7DADM Clackamas River 0 to Temperature Summer 2010 Rearing: 17.8 C Cat 4A 22.9 Tualatin River 0 to Temperature Summer 2002 Rearing: 17.8 C Cat 4A 44.7 Willamette River 0 to Temperature Year Around 2010 Salmon and Cat 4A 50.6 (Non-spawning) steelhead migration corridors: 20.0 C 7DADM Cow Creek 0 to 2.6 Temperature Summer 2010 Rearing: 17.8 C Cat 4A Abernethy Creek 0 to Temperature Summer 2010 Rearing: 17.8 C Cat 4A 15.5 E.coli: 30-day log mean of 126 E coli organisms per 100ml OR no single sample >406 organisms per 100 ml pH: Exceedances are values high or lower than the given range Temperature: Year Around = non-spawning Dissolved Oxygen Spawning: Not less than 11.0 mg/L or 95% of saturation Assessment Categories: Cat 4A: Water quality limited, TMDL approved Cat 5: Water quality limited, 303(d) list, TMDL needed

2.3 E. coli

Table 4- Number of samples and exceedances for each station that measured E. coli from 1/1/2000 to 1/1/2017; when sufficient data exists, geometric mean was calculated and included in table Station ID* Sample Type Date Range N Exceedances %Exceedance Slope p-value Sig level 11233 Single Sample 2012-2016 23 1 4.3 -4.75 0.677 Not Sig 13070 Single Sample 2012-2016 39 0 0 0.12 0.88 Not Sig 10339 Single Sample 2013-2016 18 0 0 5.0 1.0 Not Sig 14008 Single Sample 2012-2016 17 0 0 -0.33 0.836 Not Sig *Station 11233: Clackamas River at High Rocks (Old Hwy Station 10339: Willamette River at Canby Ferry 213) Station 14008: Clackamas River at Memaloose Road Station 13070: Clckamas River at McIver Park (Upper Boat Ramp)

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Figure 6- Status of E. coli at station 11233, a single exceedance of the water quality standard occurred in 2014

2.4 pH Table 5- pH trends for the Clackamas basin, all stations are located in freshwater Station ID* Observations Exceedances %Exceedance Slope p-value USGS 14210000 153,704 0 0 0.01 0.125 USGS 14209710 156,062 8 0 -0.03 0.001 USGS 14211010 237,817 3786 1.6 -0.02 0.043

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*Station USGS 14209710: Clackamas River at Carter Bridge, Station USGS 14211010: Clackamas River near Oregon City, near Estacada OR OR Station USGS 14210000: Clackamas River at Estacada, OR

Table 6- pH status for Clackamas Subbasin, all stations are located on freshwater Station ID* Date Range Observations Exceedances %Exceedance 10339 2013-2016 20 0 0 11233 2012-2016 26 0 0 13070 2012-2016 69 0 0 14008 2012-2016 25 0 0 *Station 11233: Clackamas River at High Rocks (Old Hwy Station 10339: Willamette River at Canby Ferry 213) Station 14008: Clackamas River at Memaloose Road Station 13070: Clckamas River at McIver Park (Upper Boat Ramp)

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Figure 7- pH trends at station USGS 14209710; two exceedances occurred in 2015 and 2016

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Figure 8- pH trends for Clackamas River at USGS station 14211010

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2.5 Temperature Table 7- Temperature trends within the Clackamas Ag WQ management area Note: N refers to the 7-day average daily maximum *Station ID Station Description Time N Total % Spawning % Summer Period Exceedances Exceedance Exceedances USGS 14211010 Clackamas River 2002-2017 5234 2246 33.3 61.7 Near Oregon City, OR USGS 14210000 Clackamas River at 2001-2017 5284 1348 13.3 68.0 Estacada, OR USGS 14209710 Clackamas River at 2005-2017 4178 266 3.7 16.0 Carter Bridge near Estacada, OR *Station USGS 14209710: Clackamas River at Carter Bridge, Station USGS 14211010: Clackamas River near Oregon City, near Estacada OR OR Station USGS 14210000: Clackamas River at Estacada, OR

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Figure 9- USGS 14211010 trends, salmon and trout rearing and migration, spawning Oct 15-May 15. Majority of exceedances in July with no summer trend.

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Figure 10- USGS 14210000 trends, core cold water habitat, spawning Sept 1 – June 15. Majority of exceedances in August with no summer trend.

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Figure 11- USGS 14209710 trends, core cold water habitat, spawning Sept 1 – June 15. No trend.

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2.6 Dissolved Oxygen

Table 8- Dissolved Oxygen trends within the Clackamas Ag WQ management area Station ID Station Description N Exceedances %Exceedance 10339 Willamette River at Canby 133 0 0 Ferry 11233 Clackamas River at High 102 11 10.8 Rocks (Old Hwy 213) 13070 Clackamas River at McIver 173 25 14.5 Park (Upper Boat Ramp) 14008 Clackamas River at 109 4 3.7 Memaloose Road USGS 14209710 Clackamas River at Carter 162,097 14,926 9.2 Bridge near Estacada, OR USGS 14210000 Clackamas River at 152,155 32,378 21.3 Estacada, OR USGS 14211010 Clackamas River near 233,101 17,857 7.7 Oregon City, OR *Station USGS 14209710: Clackamas River at Carter Bridge, Station 11233: Clackamas River at High Rocks (Old Hwy near Estacada OR 213) Station USGS 14211010: Clackamas River near Oregon City, Station 13070: Clckamas River at McIver Park (Upper Boat OR Ramp) Station USGS 14210000: Clackamas River at Estacada, OR Station 10339: Willamette River at Canby Ferry Station 14008: Clackamas River at Memaloose Road

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Figure 12- Dissolved Oxygen trends from 2007 to 2017. Spawning timeframe exists from Sept 1 – June 15. Cold-water aquatic fish use designation.

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Figure 13: Dissolved oxygen trends from 2007 to 2017. Spawning timeframe exists from Sept 1 – June 15. Cold-water aquatic fish use designation.

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Figure 14- Dissolved oxygen trends from 2007 to 2017. Spawning timeframe exists from October 15 - May 15. Cold-water aquatic fish use designation.

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Figure 15- Dissolved oxygen trends from 2000 to 2015. Spawning timeframe exists from October 15 - May 15. Cold-water aquatic fish use designation. The red line represents the water quality standard.

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Figure 16- Dissolved oxygen trends from 2000 to 2015. Spawning timeframe exists from Sept 1 – June 15. Cold-water aquatic fish use designation. The red line represents the water quality standard.

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Figure 17- Dissolved oxygen trends from 2000 to 2015. Spawning timeframe exists from Sept 1 – June 15. Cold-water aquatic fish use designation. The red line represents the water quality standard.

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2.7 Parameter Summary

Figure 18- Summary of stations that fit the criteria for status and trends analysis. A single exceedance within the last two years of available defined whether a station was ‘Meeting’ or ‘Not Meeting’. Trend was determined by significant trends associated with long-term datasets. Dissolved oxygen was not assessed for trends. For details on when exceedances of the WQ standard occurred, see sections 2.3-2.6. Only significant trends were reported.

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3. Conclusions • What are the overall trends11? o Temperature: Three stations had sufficient data to calculate the seven day average daily maximum for temperature. All three stations are continuous USGS monitors sites. At all three stations, the majority of exceedances of the water quality standard occurred in the summer, with no significant trend at any monitoring station. o pH: Three stations had sufficient data to assess pH water quality trends in the Clackamas Subbasin. All three stations are continuous USGS monitoring sites. Station USGS 14210000 had no exceedances of the pH water quality standard between 2007 and 2017, while station USGS 14211010 had consistent exceedances of the water quality standard for the entire timeframe (1.6% exceedance), though the majority of results were in compliance with the water quality standard. Station USGS 14209710 had no exceedances of the water quality standard until 2015, in which there were eight exceedances between 2015 and 2017 (<1% exceedance). All exceedances at station USGS 14209710 and USGS 14211010 were alkaline. Four stations (10339, 11233, 13070, and 14008) had sufficient data to assess status of pH. None of these stations had exceedances of the water quality standard. o E.coli: Four stations had sufficient data to assess trends in E. coli within the Clackamas Subbasin. All stations had grab sample data from 2012-2016 except station 10339 which had data from 2013-2016. Station 11233 had a single exceedance of the water quality standard (4.3% exceedance) in 2014, while all other stations (13070, 10339, 14008) had no exceedances of the water quality standard in the timeframe. o Dissolved Oxygen: Seven monitoring stations had sufficient data to assess water quality status and trends of dissolved oxygen within the Clackamas Subbasin. Four monitoring stations were grab sample sites, with dates ranging from 2000 to 2016 (10339, 11233, 13070, 14008) and three stations were continuous USGS monitoring sites from 2007 to 2016. The USGS stations had consistent summer exceedances of the spawning water quality standard (primarily September/October), station USGS 14211010 also had consistent exceedances of the cold-water aquatic life water quality standard. Grab sample stations 11233, 13070, and 14008 also had consistent exceedances of the water quality; stations 10339 and 14008 had exceedances of the water quality standard in the long term dataset, however they were in compliance of the water quality standard between 2014 and 2016.Station 10339 had no exceedances of the water quality standard between 2000 and 2016.

11 Station Descriptions: • Station 34198: Willamette River at Jon Storm Park boat Dock • Station 10339: Willamette River at Canby Ferry • Station 11233: Clackamas River at High Rocks (Old Hwy 213) • Station 13070: Clackamas River at McIver Park (Upper Boat Ramp) • Station 14008: Clackamas River at Memaloose Road • Station USGS 14211010: Clackamas River near Oregon City, OR • Station USGS 14210000: Clackamas River at Estacada, OR • Station USGS 14209710: Clackamas River at Carter Bridge, near Estacada, OR

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• Is the monitoring data adequate to address status and trends in relation to WQ standards and TMDL load allocations? o Additional data is needed to evaluate site potential vegetation on the agricultural land, which would require remote sensing data to determine tree heights and calculate effective shade. o Within the Clackamas Subbasin ODA Management Area, which includes a portion of the middle Willamette River and tributaries, one station on the Willamette River is the most influenced by urban and agricultural practices, with 21% agricultural land use (Stations 10339). Station 10339 (Willamette River at Canby Ferry) had sufficient data to assess dissolved oxygen and E. coli status and trends and had no exceedances of the water quality standard for either parameter. o No grab sample monitoring locations had exceedances of the pH water quality standard, the only site with consistent pH exceedances was a continuous USGS monitoring location (USGS 14211010) which is located on Clackamas River near Oregon City. o Spawning designated uses are not supported at all sites with continuous dissolved oxygen data (USGS-14211010, USGS-14210000, USGS-14209710) due to exceedances of the dissolved oxygen water quality standard which primarily occurred during the summer/fall. o Site 14209710 has no agricultural land contribution and exceedances are limited to spawning time period only. Site 14210000 has minimal agricultural land contribution and exceedances are limited to spawning time period only. Site 14211010 has 6.7% overall contributing area in agricultural land but this and is concentrated in the more immediate upstream vicinity of this site and the exceedances extend into the non-spawning time period at this location. o At stations with grab sample dissolved oxygen data (10339, 11233, 13070, 14008), many samples were in exceedance of the dissolved oxygen concentration water quality standard, but were in compliance of the water quality standard because they met the dissolved oxygen saturation standard.

Additional Data DEQ and basin partners have collected data in the Clackamas Subbasin but many of those data are not available in sufficient quantity or frequency to evaluate trends. The data may be more indicative of water quality status on land draining agricultural and suburban/urban land use. The DEQ Basin Coordinator will present an overview of this additional data in the Local Advisory Committee review meeting.

Clackamas River Basin Council: • Macroinvertebrate data: 2013 and 2014 data collected by the watershed council and analyzed by Cole Ecological

DEQ data: • Macroinvertebrate data: 2002-2006 • DEQ pesticide data, 2015 detection frequency and Aquatic Life Ratio figures are included in appendix (Figures A11 and A12)

Clackamas Soil and Water Conservation District Data:

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• Samples Collected by Clackamas Soil and Water Conservation district and analyzed for pesticides . Additional data includes field parameters, nutrients and E. coli analyses, from monthly winter sampling at about 6 agricultural land use sites over three years.

Clackamas County: • Municipal stormwater permit data from Clackamas County for metals and E. coli at Rock and Sieben Creeks which have some agricultural land use.

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Appendix A Pages A-1 through A-X

Revision Date Changes Editor

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Table A- 1- Stations with sufficient data for analysis; values represent amount of data points in each given year. Station ID Analyte 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017

USGS-14209710 NA NA NA NA NA NA 4322 11035 17136 17312 17778 17625 17824 17787 17716 17433 49 pH USGS-14210000 NA NA NA NA NA NA 4375 17532 17472 17468 9533 17703 17434 17141 17473 17523 48 pH USGS-14211010 NA NA NA NA NA NA 4410 17093 16478 17478 17396 26409 34470 34383 34634 34968 96 pH USGS-14209710 NA NA NA NA 254 355 364 350 365 361 365 366 365 364 362 360 NA Temperature USGS-14210000 174 365 365 357 332 324 354 366 365 365 200 366 364 352 361 362 NA Temperature USGS-14211010 NA 195 358 366 365 359 365 357 351 365 365 366 365 365 365 366 NA Temperature 10339 NA NA NA NA NA NA NA NA NA NA NA NA 2 6 5 6 NA E. coli 11233 NA NA NA NA NA NA NA NA NA NA NA 1 6 6 6 6 NA E. coli 13070 NA NA NA NA NA NA NA NA NA NA NA 2 7 10 10 12 NA E. coli 14008 NA NA NA NA NA NA NA NA NA NA NA 1 5 2 6 4 NA E. coli 10339 NA NA NA NA NA NA NA NA NA NA NA NA 2 6 5 6 NA Dissolved Oxygen 11233 NA NA NA NA NA NA NA NA NA NA NA 1 6 6 6 6 NA Dissolved Oxygen 13070 NA NA NA NA NA NA NA NA NA NA NA 2 12 12 11 12 NA Dissolved Oxygen 14008 NA NA NA NA NA NA NA NA NA NA NA 1 6 4 6 5 NA Dissolved Oxygen 34198 NA NA NA NA NA NA NA NA NA NA NA 2 NA NA NA NA NA Dissolved Oxygen 38020 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1 NA NA Dissolved Oxygen 38021 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1 NA NA Dissolved Oxygen 38022 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 2 NA NA Dissolved Oxygen 38023 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1 NA NA Dissolved Oxygen 38024 NA NA NA NA NA NA NA NA NA NA NA NA NA NA 1 NA NA Dissolved Oxygen

State of Oregon Department of Environmental Quality 1

Figure A- 1- E. coli trends over a four-year period, no exceedances of the water quality standard occurred

State of Oregon Department of Environmental Quality 1

Figure A- 2- E. coli trends over a three-year period, no exceedances of the water quality standard occurred

State of Oregon Department of Environmental Quality 2

Figure A- 3- E. coli trends over a four-year period, no exceedances of the water quality standard occurred

State of Oregon Department of Environmental Quality 3

Figure A- 4- pH trends from 2007-2016, no exceedances of the water quality standard occurred

State of Oregon Department of Environmental Quality 4

Figure A- 5- pH status from 2013-2016, no exceedances of the water quality standard occurred

State of Oregon Department of Environmental Quality 5

Figure A- 6- pH status from 2012-2016, no exceedances of the water quality standard occurred

State of Oregon Department of Environmental Quality 6

Figure A- 7- pH status from 2012-2016, no exceedances of the water quality standard occurred

State of Oregon Department of Environmental Quality 7

Figure A- 8- pH status from 2012-2016, no exceedances of the water quality standard occurred

State of Oregon Department of Environmental Quality 8

Figure A- 9- Trends in dissolved oxygen with a cool water aquatic life criterion applied and no spawning

State of Oregon Department of Environmental Quality 9

Figure A- 10- Trends in dissolved oxygen with a cool water aquatic life criterion applied and no spawning

State of Oregon Department of Environmental Quality 10

Figure A- 11- Pesticide detection frequency in the Clackamas Basin, provided by the Pesticide Stewardship Partnership program

State of Oregon Department of Environmental Quality 11

Figure A- 12- Aquatic Life Ratio and Detection Frequency of pesticides in the Clackamas Basin, provided by the Pesticide Stewardship Partnership program

State of Oregon Department of Environmental Quality 12