# Tribal Water Quality Assessment Report (2005)

> Briefs, arguments, decisions, and more.

URL: https://www.frixlaw.com/law-library/documents/tribal%3Aconfederated_clusi%3A8802d01efc8340c5

## Record

- **Collection:** Tribal code
- **Document type:** Tribal code

## Text

Tribal Water Quality Assessment Report
(October 2005 to September 2006)

Deliverable as Specified in Clean Water Act Section 106
Grant # BG-96005701-0

Prepared By:
Confederated Tribes of
Coos, Lower Umpqua, and Siuslaw Indians
Department of Natural Resources
1245 Fulton Avenue
Coos Bay, Oregon

December 27, 2006

Background
The Environmental Division is a branch under the Department of Natural Resources with
a mission statement is to research, monitor, assess, manage, use, conserve, protect, and
restore the natural resources of the Confederated Tribes’ Ancestral Territory, consistent
with Tribal values. The Water Quality Program (WQP) was developed to monitor water
quality conditions of tribal waters and monitor the quality of waters pertaining to tribal
lands. The WQP assess the ecological health of the Ancestral Watersheds and develops
plans, best management practices, standards, and ordinances to protect these Tribal
waters for their multiple ecological, cultural, economic, and intrinsic values. In 2002, the
US Environmental Protection Agency (EPA) agreed to treat the Tribes "in a manner
similar to a state" under the authority of the Clean Water Act. In 2003, the
Tribes completed an EPA approved Quality Assurance Project Plan (QAPP 1.8) for the
water quality monitoring program. Early in 2004, the Tribes initiated the first ever water
quality monitoring program. Water quality data collection targeted five core parameters:
water temperature, turbidity, salinity, pH, and dissolved oxygen. Data collection was
conducted at spring high-high and low-low tides, requiring sampling to be conducted at
all hours of the day and night. Data collection was expanded in 2006 with the
implementation of an EPA approved QAPP 2.0. The WQP installed YSI continuous data
loggers at estuarine sites to improve and increase tidal data collection. The WQP also
expanded to include chlorophyll and bacteria parameters into the WQP. The WQP is
funded by EPA through Section 106 of the Clean Water Act.

Purpose
EPA’s Guidance on Awards of Grants to Indian Tribes under Section 106 of the Clean
Water Act requires that tribes collect, assess, and report annually on water quality
monitoring data collected using Clean Water Act Section 106 funding. The following
annual Water Quality Assessment Report covers all tribal water quality data collected in
the 2005-2006 water year (October 2005-September 2006). In addition to this report all
water quality data collected by the WQP will be submitted with this report to EPA.

Atlas of Tribal Waters
The following table is an estimate of our tribal waters (as of 1/1/2007) using our most
current GIS data.
Atlas of Tribal Waters
Total Number of Stream Miles
0.03 miles
Total Number of Lake Acres
54.4 acres
Total Number of Wetland Acres
3.34 acres
Total Number of Estuary Frontage
0.69 miles

2

Parameters
EPA’s Guidance on Awards of Grants to Indian Tribes under Section 106 of the Clean
Water Act for Fiscal Years 2007 and Beyond [EPA 832-R-06-003] requires that Tribes
include and annually report on the following nine water quality parameters:
¾ Dissolved Oxygen
¾ pH
¾ Total phosphorus
¾ Total nitrogen
¾ Water temperature
¾ Turbidity
¾ Macroinvertebrates
¾ E. Coli or fecal coliform
¾ Basic habitat information
The WQP currently collects data on the following five of the nine EPA recommended
parameters.
¾ Dissolved Oxygen
¾ pH
¾ Water Temperature
¾ Turbidity
¾ E. coli and Enterococcus
Efforts are under way by the WQP to update our Quality Assurance Project Plan (QAPP)
to incorporate all EPA required parameters (Total Phosphorus, Total Nitrogen,
Macroinvertebrate, and Basic Habitat Information).

Monitoring Methods and Frequency
Estuarine Continuous Monitoring
One data logger is deployed at each of the three permanent monitoring stations. Sites are
accessed at high to mid-outgoing tide in a small skiff equipped with an outboard motor.
During transport, each sonde is wrapped in a tap water-soaked white towel and placed
horizontally in a rubber bin for insulation against jarring. To deploy, the data loggers are
lowered by chain into protective cases (constructed from 4"-diameter ABS plumbing
pipe). The ABS cases are drilled out to ensure adequate tidal flushing and exposure of
the probes to ambient water conditions. The ABS cases are affixed vertically to existing
log pilings driven into the channel substrate. A bolt prevents the data logger from
descending beyond the ABS pipe and ensures that the logger monitors at the same depth
on every deployment.
During retrieval, the sondes are again wrapped in a water-saturated white towel and
placed in a rubber bin for transport to the lab. To record post-deployment Dissolved
Oxygen in 100% water-saturated air, at least two data points are recorded after the sonde
reaches ambient temperature and while it is wrapped in the towel. The other postdeployment calibrations are performed in the lab prior to cleaning to determine if

3

instrument drift has occurred and to evaluate the validity of the data. Sonde cleaning and
calibration of the DO, Conductivity, Depth, pH, Turbidity, and Chlorophyll probes are
performed as outlined in the YSI manual. For Conductivity and Salinity, YSI calibrator
solution (10,000 μS/cm) is used without dilution. For pH calibrations, pH 7 and 10
solutions are used. A two-point calibration is used for Turbidity using 0 NTU and 123
NTU. A one-point (0 NTU) Chlorophyll calibration is performed. The depth sensor is
calibrated in air at sea level. The DO membranes are replaced prior to every deployment,
calibrated, and allowed to stretch for 16-24 hours. The DO probes are re-calibrated before
deployment, if necessary.
As a quality assurance check, field calibrations are recorded during sonde deployment
and retrieval. As close to the 30-minute sonde recording time as possible, a hand-held
YSI 556 records DO, Salinity, Specific Conductivity, and Temperature both at the
surface and at the level of the sonde array. Surface grab samples of water for pH and
turbidity are taken for bench top analysis.
The WQP staff complete data logger retrieval and deployment approximately every two
weeks weather permitting.
Stream Discrete Monitoring
Water temperature, dissolved oxygen, salinity/conductivity, pH, bacteria (e. coli and
Enterococcus), and turbidity data are collected semi-monthly at the Tribes’ freshwater
monitoring site. A combination of handheld meters (YSI 556 multi-probe meter, Hach
2100-P Turbidimeter, and Beckman 450 ionic pH meter) and sample bottles are used to
measure and collect discrete samples. The target time of day for sample collection at the
Tribes’ freshwater site is 2:00 p.m. In addition, a water sample is collected for in house
analysis of e. coli and Enterococcus using IDEXX brand Colilert -18 and enterolert
reagent and the IDEXX QuantiTray 2000 analytical system. Calibrated and audited
Vemco water temperature data loggers are deployed at the site from June thru September
and record data at 30 minute intervals.
Estuarine Discrete Monitoring
The WQP currently monitors estuarine water quality at four sites and has established
three long-term continuous monitoring stations within two estuaries (Siuslaw and Coos
Bay) along the central and south central Oregon coast. These sites were established to
collect essential baseline information and to improve the Tribes’ understanding of tidal
dynamics and watershed inputs occurring within tribal waters. The estuarine sites are
sampled using the discrete sampling methodology described in the previous Stream
Water Quality Monitoring section.
Bacteria Monitoring Research Methods
Water samples for microbiological analysis are collected at all sites semi-monthly for in
house analysis of E. coli and Enterococcus using IDEXX brand Colilert -18 and
Enterolert reagent per the IDEXX QuantiTray 2000 analytical system. Water samples of
approximately 100ml (with adequate head-space for mixing), are collected using
disposable pre-sterilized IDEXX sample bottles. All bacteria and ancillary grab samples
are placed in a cooler on ice while in transport to the lab.

4

Applied Water Quality Standards
The Tribes are in the process of developing tribal water quality standards applicable to
tribal lands. Until these standards are completed and approved by Tribal Council, the
WQP compares water quality data collected with the numeric standards within the State
of Oregon’s water quality standards. These water quality standards can be found on the
Oregon Department of Environmental Quality’s website
(http://www.deq.state.or.us/wq/wqrules/Div041/OAR340Div041.pdf).
The following table shows the numeric water quality standards that were applied to the
water quality data collected during this reporting period.
Water Quality Standards Applied to Tribal Water Quality Data
Parameter
Estuarine
Freshwater
Dissolved Oxygen
6.5 mg/L
6.0 mg/L
pH
6.5-8.5
6.5-8.5
Water Temperature
18°C (64º F)
18°C (64º F)
Turbidity
5 NTU Low Flow-50 3 NTU Low Flow-8
NTU High Flow*
NTU High Flow*
Salinity/Conductivity
None
None
*Low flow begins June 1st and ends September 30th; high flow begins October 1st and ends May 30th

Oregon Water Quality Standards for Each Parameter
Dissolved Oxygen(Rule No. 340-041-0016)
(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.
(5) For estuarine water, the dissolved oxygen concentrations may not be less than 6.5
mg/l (for coastal water bodies);
pH (hydrogen ion concentration)(Rule No. 340-041-0021)
(1) Unless otherwise specified in OAR 340-041-0101 through 340-041-0350, pH values
(Hydrogen ion concentrations) may not fall outside the following ranges:
(b) Estuarine and fresh waters: 6.5-8.5.

5

Water Temperature(Rule No. 340-041-0028)
(1) Background. Water temperatures affect the biological cycles of aquatic species and
are a critical factor in maintaining and restoring healthy salmonid populations throughout
the State. Water temperatures are influenced by solar radiation, stream shade, ambient air
temperatures, channel morphology, groundwater inflows, and stream velocity, volume,
and flow. Surface water temperatures may also be warmed by anthropogenic activities
such as discharging heated water, changing stream width or depth, reducing stream
shading, and water withdrawals.
(c)The seven-day-average maximum temperature of a stream identified as having salmon
and trout rearing and migration use may not exceed 18°C.
Turbidity(Rule No. 340-041-0036)
The current Oregon Department of Environmental Quality (ODEQ) turbidity standard
specifically states that “[n]o more than a ten percent cumulative increase in natural
stream turbidities may be allowed, as measured relative to a control point immediately
upstream of the turbidity causing activity.”
DNR staff interviewed ODEQ staff to determine whether an alternate turbidity standard
could be applied in the interpretation of our discrete grab sample turbidity data. ODEQ
recommended that DNR apply an ambient background standard of 50 NTU to high flow
and 5 NTU to low flow estuarine turbidity data. ODEQ staff explained that studies of the
short term exposure of fish (e.g. salmon and trout) to these seasonal NTU’s have been
cited by previous studies as impacting fish behavioral response and growth rate – relative
to the fish’s perception of itself as either predator or prey (e.g. impact to juvenile
response time to predator or diminished foraging opportunities). Fresh water analysis of
the Tribes’ Sixes River data was based on median ambient high flow (8 NTU) and low
flow (3NTU) conditions of Oregon’s rivers listed in Table 3.6 of ODEQ’s Oct. 2005
DRAFT ‘Technical Basis for Revising Turbidity Criteria’. Within the “Oregon Water
Quality Index Report: Water Years 1995 – 2004,” ODEQ defines low summer flow as
beginning June 1st and ending September 30th, and high seasonal flow as beginning
October 1st and ending May 30th.
Salinity/ConductivityNo standard exists for this parameter. This parameter is primarily used to detect fresh and
salt water mixing and can be used as an indicator parameter for other pollutants.

Coordination and/or Collaboration with Other Organizations
The WQP works with local watershed associations to share technical expertise, strategies,
and water quality datasets. During this reporting period the WQP provided datasets to the
Coos Watershed Association (www.cooswatershed.org) and the Siuslaw Watershed
Council (www.siuslaw.org) to assist in the development of grant proposals and
restoration projects. Data was also provided to Greene Point Consulting to assist in a
wetland project on the North Fork Siuslaw River.
6

Outside Lab Support
No outside lab support was utilized during this reporting period.

Data Summarization and Management
Characteristics of Water Quality Monitoring Data – Source: USGS Statistical Methods
in Water Resources, Helsel and Hirsch
Data analyzed by our program have the following characteristics:
•

A lower bound of zero. No negative values are possible.

•

Presence of ‘outliers’, observations considerably higher or lower than most of the
data, which infrequently but regularly occur.

•

Positive skewness. Skewness can be expected when outlying values occur in only
one direction.

•

Non-normal distribution, due to skewness, presence of outliers, and the lower
bound of zero. Symmetry does not guarantee normality. Symmetric data with
more observations at both extremes (heavy tails) that occurs for a normal
distribution are also non-normal.

•

Seasonal patterns. Values tend to be higher or lower in certain seasons of the year.

•

Autocorrelation. Consecutive observations tend to be strongly correlated with
each other. For the most common kind of autocorrelation in water resources
(positive autocorrelation), high values tend to follow high values and low values
tend to follow low values.

•

Dependence on other uncontrolled variables. Values strongly covary with water
discharge, hydraulic conductivity, sediment grain size, or some other variable.

The summarization and graphing methods chosen for the analysis of the WQMP data
presented in this report were selected to recognize these common characteristics while
facilitating a quick and easy to understand visual and tabular reference for potential
trends in water quality captured by our data.

7

Data Summarization and Analysis Methodology
The following sections describe the methods of data analysis and summarization
presented in this report and attempt to explain why they were chosen over other methods.
Outliers
Outliers, observations whose values are quite different than others in the data set, are not
deleted from our data set unless they fall outside of instrument specifications. For our
purposes, outliers may be the most important points in our data set and are signals for
what parameters should be further investigated. Outliers can have one of three causes:
1.

A measurement or recording error – These data are deleted from the data sets during the
QA/QC procedures.

2.

An observation from a population not similar to that of most of the data, such as an elevated
spike in turbidity caused by a construction project rather than precipitation.

3.

A rare event from a single population that is quite skewed.

Rather than eliminating actual (and possibly very important) data in order to use analysis
procedures requiring symmetry or normality, procedures resistant to outliers have been
employed in analysis of those data presented in this document. Computing the sample
mean alone may be of less value because an outlier observation, either high or low, has a
much greater influence on the overall mean than does a more typical observation. This
sensitivity to the magnitudes of a small number of points in the data set defines why the
mean is not a “resistant” measure of location (Fig. 1). It is not resistant to changes in the
presence of, or changes in the magnitudes of, a few outlying observations. The median,
however, is only minimally affected by the magnitude of a single observation, being
solely determined by the relative order of observations. This resistance to the effect of a
change in value or presence of outlying observations is the main reason we have chosen
to include the median in our summarization. In this case, we have chosen to let the data
guide which analysis procedures are employed, rather than altering the data in order to
implement analysis procedures that may be too restrictive for the informational purposes
of this report.
August 2006 Continuous Data Summary
North Fork Siuslaw Sonde
Stats
Q3
Max
Median
Min
Q1
Mean
Std Dev

Temp
18.80
21.20
17.60
11.00
16.20
17.37
1.99

SpCond
39.59
50.26
34.62
15.21
28.77
33.99
7.56

Sal
25.30
32.80
21.80
8.90
17.80
21.45
5.20

DO pct
101.03
153.10
85.25
46.70
72.10
88.72
21.38

DO mg/l
8.50
13.20
7.20
4.10
6.10
7.48
1.79

Depth
3.02
4.08
2.50
1.00
1.98
2.49
0.68

pH
7.70
8.40
7.50
6.90
7.20
7.48
0.33

Turb
4.00
522.00
3.00
1.00
3.00
4.05
15.47

Fig.1 Turb and D.O. data summarized in this table reflect the effect of outliers on the
mean and the median
8

Measure of Skewness
The continuous water quality monitoring data collected by our program tend to be
skewed, meaning that data sets are not symmetrical around the mean or median, with
extreme values extending out longer in one direction. Figures 2-4 illustrate the potential
skewness of our data. When extreme values extend the right tail of distribution, as they
do in figures 1 & 2, the data are said to be skewed to the right, or positively skewed. Left
skewness, when the tail extends to the left as in figure 4, is called negative skew.

Distribution of August 2006 North Fork Siuslaw Sonde Turbidity Data
700
Median: 3.0

Number of Samples Recorded

600

Mean: 4.05

500

400
Total
300

200

100

0
1

2

3

4

5

6

7

8

9

10

11

12

14

18

24

293

NTU Value

Fig. 2

9

522

Distribution of August 2006 North Fork Siuslaw Sonde Dissolved Oxygen Concnetration
Data
50

45

Median:7.20

Mean: 7.48

40

35

30

25

20

15

10

5

0
Dissolved Oxygen Value (mg/l)

Fig. 3
Distribution of August 2006 North Fork Siuslaw Sonde Temperature Data
40

35

30

25

20

Total

15

10

5

0
Temperature Value

Fig. 4

10

When the data are skewed the mean is not expected to equal the median, but is pulled
toward the tail of distribution (Fig. 1 & 2). Thus for positive skewness (Fig. 1 & 2) the
mean exceeds more than 50 percent of the data (Fig. 1). The standard deviation is also
inflated by data in the tail (Fig.1). Therefore, tables of summary statistics which include
only the mean and standard deviation may not describe the majority of the data very well
because both will be inflated by outliers. For this reason, summary tables like those
presented in this report, which include the median and other percentiles, have greater
applicability to potentially skewed data sets. Skewed data also call into question the
applicability of hypothesis tests which are based on assumptions that the data have a
normal distribution. These tests, called parametric tests, may be of questionable value
when applied to skewed data sets and it is best to determine sooner rather than later
whether or not these tests apply.

Interquartile Range
The interquartile range (IQR) is a commonly used resistant measure of spread. It
measures the range of the central 50 percent of the data, and is not influenced at all by the
25 percent on the other end. The IQR is defined as the 75th percentile minus the 25th
percentile. The 75th, 50th (median) and 25th percentiles split the data into four equal-sized
quarters. The 75th percentile (also called the upper quartile or Q3) is a value that exceeds
no more than 75 percent of the data and is exceeded by no more than 25 percent of the
data. The 25th percentile (also called the lower quartile or Q1) is a value that exceeds no
more than 25 percent of the data and is exceeded by no more than 75 percent.
Graphical Data Analysis
Continuous Data
Exploratory analysis of our continuous water quality monitoring data has been applied to
these data in the form of box plots. This is an inductive procedure that has been used to
summarize, rather than test, these data. The results of the exploratory analysis of these
data will provide guidance toward the selection of appropriate deductive hypothesis
testing procedures implemented by CTCLUSI for future non-point source pollution
assessments and/or reports. According to USGS Book 4. Hydrologic Analysis and
Interpretation: Statistical Methods in Water Resources, the use of histograms for data
measured on a continuous scale is not the best method for graphical analysis of these
data. The process of forcing continuous data into discrete categories may obscure
important characteristics of the distribution. Histograms are best applied to data that have
natural categories or groupings (e.g., number of individual organisms found at a stream
site grouped by species type, or the number of water-supply wells exceeding some critical
yield grouped by geological unit). It is for this reason that we have chosen to graphically
display our continuous data with boxplots.
Boxplots provide visual summaries of:
1.

The center of the data (the median)

2.

The variation or spread (interquartile range – box height)

3.

The skewness (quartile skew – the relative box halves)

4.

Presence or absence of unusual values (outliers)

11

Although boxplots do not present all of the data, presenting all of the data is more detail
than is necessary for the purposes of this report. Boxplots presented in this report provide
concise visual summaries of essential data characteristics. The format of the boxplots
presented herein is the ‘box-and-whisker plot’ consisting of a center point (the median)
splitting a rectangle defined by the upper and lower quartiles (Q3 and Q1). Whiskers of
the box are lines drawn from the ends of the box to the maximum and minimum of the
data (Fig. 5). Thus a large amount of information is contained in a very concise
illustration.
Siuslaw River Mainstem Temperature Trend: Water Year 2006
25
DEQ Upper Limit for Salmon and Trout
Rearing and Migration: 18 ° C

Units Celsius

20

15

Q3
10
Max
Median
Min

5

Q1
DEQ
STD

0
Apr-06

May-06

Jun-06

Jul-06

Aug-06

Sep-06

Date

Fig. 5
Boxplots effectively illustrate the characteristics of data for a single variable, and
accentuate outliers for further inspection.
Discrete Data
In previous reports we have used overlapping histograms to display our discrete sample
data. However, upon reading USGS technical reports, we have learned that overlapping
histograms are not recommended for the display of water quality data such as these
because histograms provide poor visual discrimination among multiple data sets. It is for
this reason that we have chosen to display those discrete water quality monitoring data
collected by our program in a line graph format.
Coded Variable Code Definitions
Sampling Station:
Sampling Site Code
North Fork Siuslaw Sonde
WQE12
Mainstem Siuslaw Sonde
WQE09
BLM Dock Sonde
WQE10
Kentuck Slough Grab
WQE03
Sixes River Grab
WQS07

Station Code
CTCNFWQ
CTCSIWQ
CTCEDWQ
CTCKSWQ
CTCSRWQ
12

The station code identifier is composed of a three letter code identifying our organization
CTC = CTCLUSI; a two letter code identifying the site NF = North Fork Siuslaw, SI =
Mainstem Siuslaw, ED = BLM Dock, KS = Kentuck Slough, SR = Sixes River; and a
two letter code identifying the type of data WQ = Water Quality.

Sonde Data Review and Editing Protocol
Our WQMP’s general philosophy for data acceptance or rejection is based on absolute
and discretionary factors.
(1) Absolute: In the first phase of data review and editing, values sometimes can be
rejected on the basis of absolute factors via software statements with no detailed analysis
of the study by the CTCLUSI data logger technician.
(2) Discretionary: These are other instances in which the data must be examined before
absolute rejection. In the second phase we are recommending that each deployment study
be evaluated at the site for anomalies prior to submission of data for inclusion in the
CTCLUSI water quality data logger database.
Absolute data rejection (1)
The value recorded in the sonde memory is outside the listed range specifications of the
instrument.
The following criteria are based on the latest YSI 6-Series Environmental Monitoring
Systems Operating Manual sensor specifications in Appendix J and are what the
CTCLUSI error checking criteria are based on.
Temperature: -5 to 45 °C
Specific Conductivity: 0 to 100 mS/cm
Salinity: 0 to 70 ppt
Dissolved Oxygen (% Saturation): 0 to 200 and 200 to 500 % air saturation
Dissolved Oxygen (mg/L): 0 to 20 and 20 to 50 mg/L
Shallow Depth: 0 to 9.1m
pH: 2 to 14 units
Turbidity: 0 to 1000 NTU
Always reject data that are outside of the range of the probes; the only exceptions to
the absolute data rejection for out-of-range values are for the Shallow depth and
Turbidity probes. These exceptions are explained under their respective headings in this
document.

13

Site Location and Description
The following sections contain general watershed and water quality information for each
of the sites actively monitored by our program. Following each site description are graphs
displaying those data pertaining to current ODEQ standards and/or any 303(d) listings for
waters running through each monitoring location. This has been done in an attempt to
provide a quick identification of impairments potentially recorded in our monitoring data.
Tables summarizing water quality data collected at the site follow the graphical analysis.

1) North Fork Siuslaw River (WQE12) [43.978039, 124.080850 – Siuslaw
Watershed]
In April 2006, CTCLUSI discontinued discrete monitoring at the Hatch Tract Hwy 126
bridge location and established a permanent continuous monitoring station upriver
approximately 600ft from the bridge site.
The North Fork Siuslaw sonde station is located in the Lower North Fork Siuslaw
watershed approximately 6 river miles from the mouth of the Siuslaw River and within
river mile one of the Lower North Fork Siuslaw River. Water quality at this site is both
tidally influenced and watershed driven. The Lower North Fork Siuslaw River is also
considered part of the Siuslaw Estuary. The North Fork Siuslaw River is 303(d) listed for
sedimentation and temperature beginning at river mile 0.4 to 27.3. The sedimentation
listing is based on the criteria of the formation of appreciable bottom sludge deposits or
the formation of any organic or inorganic deposits deleterious to fish or other aquatic life
and the impact to the beneficial use of resident fish and aquatic life. The temperature
listing is based on the salmon and trout rearing and migration beneficial use criteria
temperature not to exceed an 18°C 7-day average maximum. The North Fork Siuslaw has
also been listed as water quality limited for habitat modification. Of the parameters listed,
temperature is the only one cited by ODEQ as impacting the beneficial use of salmon and
trout rearing and migration year round and as a result ODEQ has identified this reach as
requiring a temperature TMDL.
The following graphs and tables display both the discrete and continuous water year 2006
monitoring data collected by our program at these sites. The first set of graphs compare
the discrete high tide and low tide data collected at the Hatch Tract bridge site and relate
these data to state established water quality standards. The second set of graphs and
tables were generated from data collected at the North Fork Siuslaw sonde station.

* Contamination can cause the sonde’s Turbidity Probe zero calibration to be off by +5 to +8 NTUs. So when the probe
really experiences zero turbidity, the values are -5 to -8 NTU. Due to this known small calibration error possibility, small
negative turbidity values are kept in the data file and documented as anomalous due to this small calibration error.

14

Discrete Monitoring Data Analysis – Hatch Tract Bridge

Hatch Tract High Tide v. Low Tide Temperature Comparison: 10/05 - 03/06
20
18
16
14

Celsius

12
10
8
6
4
HT Temp

2

LT Temp
DEQ STD 18°C

3/29/2006

3/14/2006

2/28/2006

2/10/2006

1/27/2006

1/12/2006

12/30/2005

12/15/2005

12/3/2005

11/16/2005

11/4/2005

10/19/2005

0

Date

Hatch Tract High Tide v. Low Tide Dissolved Oxygen Comparison: 10/05 - 03/06
16

14

12

8

6

4

2

HT DO Conc
LT DO Conc
DEQ STD 6.5 mg/l

3/29/2006

3/14/2006

2/28/2006

2/10/2006

1/27/2006

1/12/2006

12/30/2005

12/15/2005

12/3/2005

11/16/2005

11/4/2005

0
10/19/2005

mg/l

10

Date

15

Hatch Tract High Tide v. Low Tide Turbidity Grab Sample Comparison: 10/05-03/06
60

50

NTU

40

30

20

10

HT Turbidity (Four Averages)
LT Turbidity (Four Averages)
DEQ High Flow NTU: 50
DEQ Low Flow NTU: 5

3/29/2006

3/14/2006

2/28/2006

2/10/2006

1/27/2006

1/12/2006

12/30/2005

12/15/2005

12/3/2005

11/16/2005

11/4/2005

10/19/2005

0

Date

Hatch Tract High Tide v. Low Tide Salinity Comparison: 10/05-04/06
30

25

15

10

5
HT Sal
LT Sal
3/29/2006

3/14/2006

2/28/2006

2/10/2006

1/27/2006

1/12/2006

12/30/2005

12/15/2005

12/3/2005

11/16/2005

11/4/2005

0
10/19/2005

ppt

20

Date

16

North Fork Siuslaw Continuous/Sonde Data Analysis
The following box and whisker plots display sonde temperature, dissolved oxygen, and
pH data collected at this site. The graphs have been produced with the appropriate ODEQ
standards and/or 303(d) listing in an attempt to facilitate rapid visual understanding of the
trends occurring at the site. Those data presented in the temperature boxplot (Boxplot 1)
indicate that the majority of continuous temperature data collected at CTCLUSI’s North
Fork sonde station throughout July and August exceeded the salmon and trout rearing and
migration beneficial use criteria of 18°C 7-day average maximum temperature and
therefore support the 303(d) listing for temperature within the North Fork Siuslaw River.
In addition to supporting the 303(d) listing for the site, dissolved oxygen data collected at
the site indicate an additional impairment to water quality is occurring at the site.
Although the Mainstem Siuslaw River is 303(d) listed from river mile 5.7 to 105.9 as
impacting the designated beneficial use of anadromous fish for dissolved oxygen June 1st
– September 14th (based on the criteria of cold water no less than 8.0 mg/l or 90% of
saturation) and impacting the designated beneficial use of salmonids fish spawning for
dissolved oxygen September 15th to May 31st (based on the spawning criteria not less
than 11.0 mg/l or 95% saturation), the North Fork Siuslaw is not. However, our initial
analysis of the continuous data collected by our program at this site indicate that
impairments to dissolved oxygen similar to those listed for the Mainstem Siuslaw River
are occurring within the North Fork Siuslaw River (Boxplot 2). Because there is an
ODEQ standard for pH in estuaries, we generated a boxplot (Boxplot 3) displaying pH
data collected at the site. No impairments to water quality associated with pH appear to
be occurring at the site.
North Fork Siuslaw Temperature Trend: Water Year 2006
25
DEQ Upper Limit for Salmon and Trout Rearing
and Migration: 18 ° C

Units Celsius

20

15

10
Q3
Max
Median

5

Min
Q1
DEQ STD

0
Apr-06

May-06

Jun-06

Jul-06

Aug-06

Sep-06

Date

Boxplot 1.

17

North Fork Siuslaw Dissolved Oxygen Trend: Water Year 2006
14
Q3

Units mg/l

12

Max

10

Median

8

Min

Q1

6
DEQ Lower Dissolved Oxygen Limit for
Estuaries: 6.5 mg/l

DEQ
Estuarine
STD

4
DEQ Lower Dissolved Oxygen Limit for Cold
Water Anadromous Fish Use: 8.0 mg/l - June 1st
to September 14th

2

DEQ Cold
Water STD

DEQ Lower Dissolved Oxygen Limit for
Salmonid Fish Spawning: 11.0 mg/l - September
15th - May 31st

DEQ Spawn
STD

0
Apr-06

May-06

Jun-06

Jul-06

Aug-06

Sep-06

Date

Boxplot 2.

Siuslaw North Fork pH Trend: Water Year 2006
9

DEQ Upper pH Limit for Estuaries: 8.5

8

7
Q3
DEQ Lower pH Limit for Estuaries: 6.5

Units pH

6

Max

5

Median

4

Min

3

Q1

2

DEQ STD:
Upper
Limit
DEQ STD:
Lower
Limit

1

0
Apr-06

May-06

Jun-06

Jul-06

Aug-06

Sep-06

Date

Boxplot 3.

18

Monthly North Fork Temperature °C: 2006
Statistics
Q3
Max
Median
Min
Q1
Mean
Std Dev

6-Apr
12.7
16.2
12.0
8.4
11.3
12.0
1.27

6-May
16.1
19.9
14.9
11.5
13.9
15.0
1.57

6-Jun
17.3
21.6
16.5
11.3
15.4
16.4
1.75

6-Jul
20.7
22.2
19.3
14.3
17.8
19.2
1.79

6-Aug
18.8
21.2
17.6
11.0
16.2
17.4
1.99

6-Sep
17.0
19.4
16.2
10.7
15.3
16.1
1.42

Monthly North Fork Dissolved Oxygen Concentration mg/l: 2006
Statistics
Q3
Max
Median
Min
Q1
Mean
Std Dev

6-Apr
10.8
11.8
10.5
8.5
10.2
10.5
0.51

Statistics
Q3
Max
Median
Min
Q1
Mean
Std Dev

6-Apr
7.5
8.2
7.2
6.7
6.9
7.3
0.38

Statistics
Q3
Max
Median
Min
Q1
Mean
Std Dev

6-Apr
5.6
27.9
1.6
0.0
0.2
4.1
5.69

6-May
10.3
12.8
9.4
7.2
8.6
9.5
1.12

6-Jun
8.9
10.0
8.4
5.7
8.0
8.4
0.78

6-Jul
9.2
12.3
8.1
5.6
7.0
8.2
1.57

6-Aug
8.5
13.2
7.2
4.1
6.1
7.5
1.79

6-Sep
6.3
9.3
5.9
2.1
5.5
5.9
0.86

6-Aug
7.7
8.4
7.5
6.9
7.2
7.5
0.33

6-Sep
7.4
7.8
7.3
7.0
7.2
7.3
0.17

Monthly North Fork pH: 2006
6-May
7.9
8.5
7.6
6.8
7.2
7.6
0.42

6-Jun
7.6
8.1
7.4
6.7
7.1
7.4
0.34

6-Jul
7.9
8.2
7.7
7.2
7.4
7.7
0.31

Monthly North Fork Salinity ppt: 2006
6-May
16.9
28.2
10.1
0.2
4.6
11.1
7.87

6-Jun
16.2
31.5
9.4
0.1
3.6
10.8
8.36

6-Jul
23.7
29.4
20.2
9.3
16.1
19.7
5.06

6-Aug
25.3
32.8
21.8
8.9
17.8
21.5
5.20

6-Sep
26.1
32.7
23.2
11.0
19.2
22.6
4.88

Monthly North Fork Turbidity NTU: 2006
Statistics
Q3
Max
Median
Min
Q1
Mean
Std Dev

6-Apr
4.0
330.0
3.0
0.0
2.0
3.8
9.57

6-May
4.0
14.0
3.0
0.0
2.0
2.9
1.83

6-Jun
4.0
218.0
3.0
0.0
2.0
3.0
6.24

6-Jul
4.0
8.0
3.0
2.0
3.0
3.6
1.12

6-Aug
4.0
522.0
3.0
1.0
3.0
4.0
15.47

6-Sep
4.0
743.0
3.0
0.0
2.0
3.9
19.76

19

North Fork Siuslaw Bacteria Data
CTCLUSI began collecting water samples for microbiological analysis of E.coli and
Enterococcus in May 2006. Because the data set for this parameter is relatively small, no
statistical analysis has been applied to these data. The following tables list all bacteria
data collected by our program for water year 2006. Our program currently compares
single grab samples to ODEQ and EPA established numeric criteria for Freshwaters and
Estuarine Waters of either 1) no single sample exceeding 406 E.coli organisms per 100
milliliters (406 MPN) or 2) The federal Environmental Protection Agency (EPA)
recommendation of the safe standard for Enterococcus to be no more than 158 colony
forming units (158 MPN) per 100 milliliters of marine water. No samples collected by
our program during water year 2006 at this site have exceeded either of these criteria.
North Fork Siuslaw E. coli Data: Water Year 2006
Sample
ID
NFLT
NFLT
NFLT
NFLT
NFHT
NFHT
NFLT

Sample Date
5/18/06
6/16/06
7/28/06
8/11/06
8/24/06
9/7/06
9/27/06

Analyte
E. coli.
E. coli.
E. coli.
E. coli.
E. coli.
E. coli.
E. coli.

MPN/100mL
Undiluted
Sample
40.9
41.3
20.2
20.2
< 10.0
10
10

North Fork Siuslaw Enterococcus Data: Water Year 2006
Sample Date
5/18/06
7/28/06
8/11/06
8/24/06
9/7/06
9/27/06

Sample ID
NFLT
NFLT
NFLT
NFHT
NFHT
NFLT

Analyte
Enterococci
Enterococci
Enterococci
Enterococci
Enterococci
Enterococci

MPN/100mL
Undiluted
Sample
< 10.0
10
< 10.0
< 10.0
< 10.0
< 10.0

*NFLT = North Fork Low Tide
*NFHT = North Fork High Tide

20

2) Siuslaw River Mainstem (WQE09) [43.974167, 124.071111–Siuslaw Watershed]
The Siuslaw River sonde station is located in the Siuslaw River Mainstem approximately
7 river miles from the mouth of the Siuslaw River. Water quality at this site is both tidally
influenced and watershed driven. This sonde station is also located within the Siuslaw
Estuary. The Siuslaw River is 303(d) listed from river mile 5.7 to 105.9 as impacting the
designated beneficial use of anadromous fish for dissolved oxygen June 1st – September
14th. This listing is based on the criteria of cold water no less than 8.0 mg/l or 90% of
saturation. This reach of the Siuslaw River is also 303(d) listed as impacting the
designated beneficial use of salmonids fish spawning for dissolved oxygen September
15th to May 31st. This listing is based on the spawning criteria not less than 11.0 mg/l or
95% saturation. The Siuslaw River is 303(d) listed as impacting the year round (nonspawning) beneficial use for salmon and trout rearing and migration for temperature from
river mile 0 to 106. This listing is based on the salmon and trout rearing and migration
temperature criteria not greater than an 18.0 ° C 7-day average maximum. In addition to
the adverse impacts to water quality associated with low dissolved oxygen and high water
temperature, water quality in the Siuslaw River Mainstem and Estuary is also 303(d)
listed as impacting the year round beneficial use of shellfish for fecal coliform from river
mile 5.7 to 105.9. This listing is based on the criteria for the fecal coliform median of 14
organisms per 100ml or no more than 10% of samples greater than 43 organisms per 100
ml. Of the parameters listed, ODEQ cites the need for fecal coliform and temperature
TMDLs within the Siuslaw River Mainstem and Estuary.

* Contamination can cause the sonde’s Turbidity Probe zero calibration to be off by +5 to +8 NTUs. So when the probe
really experiences zero turbidity, the values are -5 to -8 NTU. Due to this known small calibration error possibility, small
negative turbidity values are kept in the data file and documented as anomalous due to this small calibration error.

21

Siuslaw River Mainstem Continuous/Sonde Data Analysis
The following box and whisker plots display sonde temperature, dissolved oxygen, and
pH data collected at this site. The graphs have been produced with the appropriate ODEQ
standards and/or 303(d) listing in an attempt to facilitate rapid visual understanding of the
trends occurring at the site. Those data presented in the temperature boxplot (Boxplot 4)
indicate that the majority of continuous temperature data collected at CTCLUSI’s
Siuslaw River Mainstem sonde station throughout July and August exceeded the salmon
and trout rearing and migration beneficial use criteria of 18°C 7-day average maximum
temperature and therefore support the 303(d) listing for temperature within the Siuslaw
River Estuary and Mainstem.
In addition to supporting the 303(d) listing for temperature at the site, dissolved oxygen
data collected at the site support the additional 303(d) listing for dissolved oxygen at this
site. Our initial analysis of continuous data collected by our program at this site supports
the seasonal impairments to water quality associated with dissolved oxygen listed for the
Mainstem Siuslaw River (Boxplot 5). Because there is an ODEQ standard for pH in
estuaries, we generated a boxplot (Boxplot 6) displaying pH data collected at the site. No
impairments to water quality associated with pH appear to be occurring at the site.

Siuslaw River Mainstem Temperature Trend: Water Year 2006
25
DEQ Upper Limit for Salmon and Trout
Rearing and Migration: 18 ° C

Units Celsius

20

15

Q3
10
Max
Median
Min

5

Q1
DEQ
STD

0
Apr-06

May-06

Jun-06

Jul-06

Aug-06

Sep-06

Date

Boxplot 4

22

Siuslaw River Mainstem Dissolved Oxygen Trend: Water Year 2006
18
Q3
16
Max
14
Median

Units mg/l

12
Min
10

Q1

8

6

4

2

DEQ Lower Dissolved Oxygen Limit for Estuaries:
6.5 mg/l

DEQ
Estuarine
STD

DEQ Lower Dissolved Oxygen Limit for Cold Water
Anadromous Fish Use: 8.0 mg/l - June 1st to
September 14th

DEQ Cold
Water STD

DEQ Lower Dissolved Oxygen Limit for Salmonid Fish
Spawning: 11.0 mg/l - September 15th - May 31st

DEQ Spawn
STD

0
Apr-06

May-06

Jun-06

Jul-06

Aug-06

Sep-06

Dates

Boxplot 5
Mainstem Siuslaw pH Trend: Water Year 2006
9
DEQ Upper pH Limit for Estuaries: 8.5

8

7

6

DEQ Lower pH Limit for Estuaries: 6.5

pH

5
Q3

4

Max
Median

3

Min

2
Q1

1
DEQ STD: Upper Limit

0

DEQ STD: Lower Limit

6-Apr

6-May

6-Jun

6-Jul

6-Aug

6-Sep

Date

Boxplot 6

23

Monthly Siuslaw Mainstem Temperature °C: 2006
Statistics
Q3
Max
Median
Min
Q1
Mean
Std Dev

6-Apr
12.4
14.6
11.7
8.6
11.1
11.8
1.15

6-May
15.5
18.3
14.6
10.8
13.4
14.5
1.64

6-Jun
17.0
20.7
16.4
10.5
15.0
16.0
2.01

6-Jul
19.6
22.1
17.9
9.7
15.7
17.5
2.71

6-Aug
19.0
21.4
17.4
9.7
15.3
16.9
2.75

6-Sep
16.7
18.3
15.6
9.5
14.5
15.3
1.73

Monthly Siuslaw Mainstem Dissolved Oxygen Concentration mg/l: 2006
Statistics
Q3
Max
Median
Min
Q1
Mean
Std Dev

6-Apr
11.0
12.2
10.6
8.5
10.2
10.6
0.67

Statistics
Q3
Max
Median
Min
Q1
Mean
Std Dev

6-Apr
7.9
8.2
7.4
6.9
7.2
7.5
0.37

6-May
10.0
12.5
9.2
6.8
8.4
9.3
1.05

6-Jun
8.4
10.7
8.0
5.4
7.7
8.0
0.67

6-Jul
9.5
13.6
8.25
3.2
7.2
8.5
1.61

6-Aug
9.8
15.8
8.3
5.2
7.3
8.7
1.94

6-Sep
6.6
9.7
6.0
2.2
5.5
5.9
1.22

Monthly Siuslaw Mainstem pH: 2006
6-May
8.0
8.5
7.8
6.8
7.5
7.7
0.36

6-Jun
7.7
8.1
7.4
6.6
7.1
7.4
0.35

6-Jul
7.9
8.3
7.7
6.9
7.4
7.6
0.31

6-Aug
7.8
8.3
7.6
6.9
7.3
7.6
0.33

6-Sep
7.4
7.8
7.3
6.8
7.2
7.3
0.20

Monthly Siuslaw Mainstem Salinity ppt: 2006
Statistics
Q3
Max
Median
Min
Q1
Mean
Std Dev

6-Apr
12.3
30.6
3.8
0.0
0.3
7.4
8.31

6-May
21.5
30.8
14.2
0.1
7.1
14.4
8.38

6-Jun
21.5
32.8
13.3
0.1
6.5
14.1
8.69

6-Jul
24.9
33.1
19.6
6.9
14.7
19.8
6.65

6-Aug
27.7
34.2
23.0
11.6
18.6
23.2
5.78

6-Sep
27.5
33.9
24.3
16.1
20.6
24.3
4.44

Monthly Siuslaw Mainstem Turbidity NTU: 2006
Statistics
Q3
Max
Median
Min
Q1
Mean
Std Dev

6-Apr
4.0
15.0
3.0
0.0
2.0
2.9
1.68

6-May
3.0
512.0
2.0
*-2.0
0.0
2.0
13.38

6-Jun
3.0
13.0
2.0
0.0
2.0
2.2
1.10

6-Jul
35.5
1000.0
3.0
0.0
2.0
99.8
213.24

6-Aug
6.0
39.0
6.0
1.0
3.0
4.9
2.26

6-Sep
4.0
498.0
3.0
*-2.0
2.0
3.8
16.21

24

Siuslaw Mainstem Bacteria Data
CTCLUSI began collecting water samples for microbiological analysis of E.coli and
Enterococcus in May 2006. Because the data set for this parameter is relatively small, no
statistical analysis has been applied to these data. The following tables list all bacteria
data collected by our program for water year 2006. Our program currently compares
single grab samples to ODEQ and EPA established numeric criteria for Freshwaters and
Estuarine Waters of either 1) no single sample exceeding 406 E.coli organisms per 100
milliliters (406 MPN) or 2) The federal Environmental Protection Agency (EPA)
recommendation of the safe standard for Enterococcus to be no more than 158 colony
forming units (158 MPN) per 100 milliliters of marine water. No samples collected by
our program during water year 2006 at this site have exceeded either of these criteria.
Siuslaw Mainstem E.coli Data: Water Year 2006
Sample Date
5/18/06
6/16/06
6/28/06
7/28/06
8/11/06
8/24/06
9/7/06
9/27/06

Sample ID
MSLT
MSLT
MSLT
MSLT
MSLT
MSHT
MSHT
MSLT

Analyte
E. coli.
E. coli.
E. coli.
E. coli.
E. coli.
E. coli.
E. coli.
E. coli.

MPN/100mL
< 10.0
10
< 10.0
10
10
< 10.0
< 10.0
20.2

Siuslaw Mainstem Enterococcus Data: Water Year 2006
Sample Date
5/18/06
7/28/06
8/11/06
8/24/06
9/7/06
9/27/06

Sample ID
MSLT
MSLT
MSLT
MSHT
MSHT
MSLT

Analyte
Enterococci
Enterococci
Enterococci
Enterococci
Enterococci
Enterococci

MPN/100mL
< 10.0
< 10.0
< 10.0
< 10.0
< 10.0
< 10.0

*MSLT = Siuslaw Mainstem Low Tide
*MSHT = Siuslaw Mainstem High Tide

25

3) BLM Boat Ramp (WQE10) [43.398019, 124.286034 – Coos Watershed]
In April 2006, CTCLUSI discontinued discrete monitoring at the Empire Dock and
established a permanent continuous monitoring station across the bay from the site
adjacent to the local BLM managed boat ramp. The continuous monitoring station is
located in the same area of the bay as the Empire Dock site and monitors the same body
of water as that previously monitored at Empire Dock in lower Coos Bay.
The BLM Sonde station is located approximately 6 river miles from the mouth of the
Lower Coos Bay Estuary. This is a marine dominated site. The Coos Estuary and its
watershed are located in the lowlands of the southwestern Oregon Coast Range. It is the
largest Oregon estuary completely contained within state boundaries and is the fifth
largest estuary in the Pacific Northwest (South Slough National Estuarine Research
Reserve (SSNERR) Management Plan, 13). The Coos River and its estuary are
considered to be a “drowned river mouth” system. ODEQ lists 303(d) impairments to
water quality in the upper bay and jetty inlet/ South Slough area of Coos Bay. The lower
jetty inlet/ South Slough (river mile 0 to 5.3) and upper bay (river mile 7.8 to 12.3) are
currently listed for fecal coliform year round. Additional listings of potential concern for
the upper bay are heavy metals (tributyltin, copper, lead, chromium, lead, and nickel) and
temperature (Oct 1 to May 31st). Although surface waters immediately adjacent to the
BLM Boat Ramp sonde station are not 303(d) listed, the monitoring of potential impacts
to water quality from non point sources located upbay and downbay of this site are within
tribal interest due to the historic association with tribal subsistence resources within the
bay such as shellfish harvesting and fishing.
The following graphs and tables display both the discrete and continuous water year 2006
monitoring data collected by our program. The first set of graphs compare the discrete
high tide and low tide data collected at the Empire Dock site and relate these data to state
established water quality standards. The second set of graphs and tables were generated
from data collected at the BLM sonde station. Data collected at both the Empire Dock
and BLM Boat Ramp site do not indicate impairments to water quality have been or are
occurring at either site.

* Contamination can cause the sonde’s Turbidity Probe zero calibration to be off by +5 to +8 NTUs. So when the probe
really experiences zero turbidity, the values are -5 to -8 NTU. Due to this known small calibration error possibility, small
negative turbidity values are kept in the data file and documented as anomalous due to this small calibration error.

26

Discrete Monitoring Data Analysis – Empire Dock

Empire Dock High Tide v. Low Tide Temperature Comparison: 10/05 - 04/06
20
18
16
14

Celsius

12
10
8
6
HT Temp

4

LT Temp

2
DEQ STD 18°C

4/14/2006

3/27/2006

3/15/2006

2/27/2006

2/9/2006

1/28/2006

1/13/2006

12/29/2005

12/14/2005

12/2/2005

11/15/2005

11/3/2005

10/18/2005

0

Date

Empire Dock High Tide v. Low Tide Dissolved Oxygen Comparison: 10/05 - 04/06
16

14

12

8

6

4

HT DO Conc

2

LT DO Conc
DEQ STD 6.5 mg/l
4/14/2006

3/27/2006

3/15/2006

2/27/2006

2/9/2006

1/28/2006

1/13/2006

12/29/2005

12/14/2005

12/2/2005

11/15/2005

11/3/2005

0
10/18/2005

mg/l

10

Date

27

Empire Dock High Tide v. Low Tide Turbidity Grab Sample Comparison: 10/05-04/06
60

50

NTU

40

30

20

10
HT Turbidity (Four Averages)
LT Turbidity (Four Averages)
DEQ High Flow NTU: 50
DEQ Low Flow NTU: 5

4/14/2006

3/27/2006

3/15/2006

2/27/2006

2/9/2006

1/28/2006

1/13/2006

12/29/2005

12/14/2005

12/2/2005

11/15/2005

11/3/2005

10/18/2005

0

Date

Empire Dock High Tide v. Low Tide Salinity Comparison: 10/05 - 04/06
35

30

25

ppt

20

15

10

5

HT Sal
LT Sal
4/14/2006

3/27/2006

3/15/2006

2/27/2006

2/9/2006

1/28/2006

1/13/2006

12/29/2005

12/14/2005

12/2/2005

11/15/2005

11/3/2005

10/18/2005

0

Date

28

BLM Continuous/Sonde Data Analysis
BLM Temperature Trend: Water Year 2006
20
DEQ Upper Temperature Limit for Salmon and
Trout Rearing and Migration: 18°c

18

16

Units Celsius

14

12

10
Q3
8
Max
6
Median
4

Min

2

Q1
DEQ STD

0
Apr-06

May-06

Jun-06

Jul-06

Aug-06

Sep-06

Date

BLM Dissolved Oxygen Trend: Water Year 2006
14

12

Units mg/l

10

8

6

DEQ Lower Dissolved Oxygen Limit for
Estuaries: 6.5 mg/l

4
Q3
Max
Median

2

Min
Q1
DEQ STD

0
Apr-06

May-06

Jun-06

Jul-06

Aug-06

Sep-06

Date

29

BLM pH Trend: Water Year 2006
9
DEQ Upper pH Limit for Estuaries: 8.5

Q3

8
Max
7
DEQ Lower pH Limit for Estuaries: 6.5

Median

Units pH

6

5

Min

4
Q1
3
DEQ
STD:
Upper
Limit
DEQ
STD:
Lower
Limit

2

1

0
Apr-06

May-06

Jun-06

Jul-06

Aug-06

Sep-06

Date

30

Monthly BLM Temperature °C: 2006
Statistics
Q3
Max
Median
Min
Q1
Mean
Std Dev

6-Apr
12.3
14.2
11.7
10.0
11.2
11.8
0.76

6-May
13.8
16.2
12.5
8.8
11.5
12.6
1.59

6-Jun
15.7
17.2
14.8
8.8
13.4
14.3
1.94

6-Jul
15.5
18.2
14.1
9.4
12.3
13.9
2.01

6-Aug
14.9
17.1
13.4
8.8
11.6
13.2
1.96

6-Sep
14.6
16.8
13.2
9.2
11.6
13.1
1.79

Monthly BLM Dissolved Oxygen Concentration mg/l: 2006
Statistics
Q3
Max
Median
Min
Q1
Mean
Std Dev

6-Apr
9.7
10.3
9.6
7.6
9.3
9.5
0.43

Statistics
Q3
Max
Median
Min
Q1
Mean
Std Dev

6-Apr
8.2
8.3
8.1
7.9
8.1
8.12
0.06

Statistics
Q3
Max
Median
Min
Q1
Mean
Std Dev

6-Apr
28.9
32.9
25.4
15.3
22.8
25.6
4.05

6-May
10.3
12.1
9.5
7.0
8.9
9.6
0.94

6-Jun
8.9
11.0
8.5
5.5
8.1
8.5
0.61

6-Jul
9.0
12.2
8.2
5.5
7.5
8.3
1.05

6-Aug
8.6
12.8
7.9
5.5
7.4
8.1
1.05

6-Sep
8.0
9.8
7.6
4.4
7.0
7.5
0.81

6-Aug
7.9
8.3
7.9
7.5
7.8
7.86
0.17

6-Sep
7.9
8.1
7.8
7.5
7.7
7.78
0.11

6-Aug
33.8
34.3
33.4
31.2
32.9
33.3
0.66

6-Sep
33.7
34.2
33.4
32.3
33.1
33.4
0.41

Monthly BLM pH: 2006
6-May
8.2
8.4
8.1
7.8
8.0
8.11
0.12

6-Jun
8.0
8.2
7.9
7.5
7.8
7.89
0.10

6-Jul
8.0
8.3
8.0
7.5
7.9
7.96
0.10

Monthly BLM Salinity ppt: 2006
6-May
31.4
33.6
29.6
22.7
28.2
29.7
2.13

6-Jun
31.4
33.8
29.7
15.7
28.1
29.7
2.06

6-Jul
32.7
33.7
32.0
12.4
31.2
31.8
1.67

Monthly BLM Turbidity NTU: 2006
Statistics
Q3
Max
Median
Min
Q1
Mean
Std Dev

6-Apr
4.0
17.0
3.0
1.0
2.0
3.7
2.14

6-May
5.0
989.0
3.0
1.0
3.0
4.6
25.70

6-Jun
5.0
935.0
3.0
*-1.0
2.0
17.8
77.37

6-Jul
17.6
1000.0
2.0
*-1.0
1.0
160.1
313.73

6-Aug
3.0
572.0
2.0
0.0
2.0
3.3
14.95

6-Sep
2.0
42.0
1.0
0.0
1.0
1.8
2.07

31

BLM Boat Ramp Bacteria Data
CTCLUSI began collecting water samples for microbiological analysis of E.coli and
Enterococcus in May 2006. Because the data set for this parameter is relatively small, no
statistical analysis has been applied to these data. The following tables list all bacteria
data collected by our program for this site during water year 2006. Our program currently
compares single grab samples to ODEQ and EPA established numeric criteria for
Freshwaters and Estuarine Waters of either 1) no single sample exceeding 406 E.coli
organisms per 100 milliliters (406 MPN) or 2) The federal Environmental Protection
Agency (EPA) recommendation of the safe standard for Enterococcus to be no more than
158 colony forming units (158 MPN) per 100 milliliters of marine water. No samples
collected by our program during water year 2006 at this site have exceeded either of these
criteria.

BLM E.coli Data: Water Year 2006
Sample Date
6/14/06
6/27/06
7/27/06
8/10/06
8/23/06
9/28/06

Sample
ID
BLM
BLM
BLM
BLM
BLM LT
BLMHT

Analyte
E. coli.
E. coli.
E. coli.
E. coli.
E. coli.
E. coli.

MPN/100mL
Undiluted
Sample
10
< 10.0
< 10.0
10
< 10.0
< 10.0

BLM Enterococcus Data: Water Year 2006
Sample
Date
7/27/06
8/10/06
9/6/06
9/28/06

Sample
ID
BLM
BLM
BLMHT
BLMHT

Analyte
Enterococci
Enterococci
Enterococci
Enterococci

MPN/100mL
Undiluted Sample
< 10.0
< 10.0
< 10.0
< 10.0

*BLM LT = BLM Low Tide
*BLM HT = BLM High Tide

32

5) Sixes River (WQS07) [42.810972, 124.445361 – Sixes River Watershed]
The Sixes River stream monitoring site is located approximately 4 river miles from the
mouth of the river. This is a freshwater site and as such water quality at the site is likely
watershed and/or storm event driven. This is a discrete monitoring site (see Stream water
Quality Monitoring under Sampling Protocols). The Sixes River headwaters in the
Klamath Mountains and flows into the Pacific Ocean north of Cape Blanco near Sixes,
Oregon, draining approximately 85,645 acres of land. This basin is one of the largest
occurring in the southern Oregon coast. The land uses in the watershed are dominated by
forestry, ranching, and rural residences. The water quality of the Sixes River and many of
its tributaries is 303(d) listed by ODEQ as impaired by elevated temperature in the
summer.
The following graphs attempt to compare baseline trends emerging from the nearly two
years of data collected semi-monthly at the Tribes’ Sixes River sampling location. Each
graph compares discrete data collected for each parameter throughout the entire water
year. Although these are discrete data, we have created line graphs in an attempt to
facilitate the quick visual identification of emerging baseline patterns occurring within
and between water years 2005 and 2006 while simultaneously comparing these data to
ODEQ standards.
In addition to the semi-monthly sampling, CTCLUSI deploys an automated VEMCO
temperature datalogger at this site during summer months. The VEMCOs are used for
long – term deployment and record the temperature at the site at 30 minute intervals.
VEMCO data collected by our program in the summer of 2006 have were viewed and
summarized
using
an
ODEQ
developed
MS
Excel
macro
called
HYDROSTAT_Simple.xls.

33

Sixes River Summer 2006 VEMCO Temperature Analysis
30.0
28.0
26.0
24.0

20.0
18.0

18.0
16.0
14.0
12.0
10.0
8.0
6.0
4.0
2.0

Dates
7-Day Avgs

Salmon and Trout Rearing and Migration STD 18C

34

09/30/06

09/23/06

09/16/06

09/09/06

09/02/06

08/26/06

08/19/06

08/12/06

08/05/06

07/29/06

07/22/06

07/15/06

07/08/06

0.0
07/01/06

Temperature degrees (C)

22.0

Sixes River Temperature Comparison: Water Year 2005 and Water Year 2006

9/29/05

9/7/05

8/24/05

8/10/05

7/13/05

6/1/05

5/18/05

4/6/05

1/20/05

1/5/05

12/21/04

12/8/04

11/24/04

10/15/04

2005 Water Year Sample Dates

25

20

Celsius

15

10

5
2006 Temp
2005 Temp
DEQ STD 18°C
9/25/06

9/5/06

8/22/06

8/9/06

7/26/06

6/29/06

6/21/06

6/1/06

5/16/06

4/28/06

4/13/06

3/28/06

3/13/06

3/1/06

2/8/06

1/25/06

1/11/06

12/28/05

12/14/05

12/1/05

11/17/05

11/2/05

10/20/05

0

2006 Water Year Sample Dates

The following table lists the discrete summer 2005 and 2006 temperature data collected
by our program at the Sixes River site that either met or exceeded the 18°C standard for
salmon and trout rearing and migration. Throughout both the 2005 and 2006 summer
sampling season, all but the early June temperature measurements either met or exceeded
the state standard. Both sets of summer data appear to indicate a summer warming trend
beginning in late May that peaks in August. The VEMCO temperature data collected
throughout August and September 2006 also indicates a similar warming trend.

Date
7/13/2005
8/10/2005
8/24/2005
9/7/2005
Date
6/21/2006
6/29/2006
7/26/2006
8/9/2006
8/22/2006
9/5/2006
9/25/2006

Time
15:13
15:15
16:00
13:52
Time
15:13
14:30
14:04
14:53
14:10
13:40
14:02

Temp °C
20.5
21.1
21.0
18.9
Temp °C
19.0
19.6
22.0
22.1
20.0
19.2
18.1

35

9/25/06

9/5/06

8/22/06

8/9/06

7/26/06

6/29/06

6/21/06

6/1/06

5/16/06

4/28/06

4/13/06

3/28/06

3/13/06

3/1/06

2/8/06

1/25/06

1/11/06

12/28/05

12/14/05

12/1/05

11/17/05

11/2/05

10/20/05

NTU

9/7/05

8/24/05

8/10/05

7/13/05

6/1/05

5/18/05

4/6/05

1/20/05

1/5/05

12/21/04

12/8/04

11/24/04

10/15/04

0.00
9/25/06

9/5/06

8/22/06

8/9/06

7/26/06

6/29/06

6/21/06

6/1/06

5/16/06

4/28/06

4/13/06

3/28/06

3/13/06

3/1/06

2/8/06

1/25/06

1/11/06

12/28/05

12/14/05

12/1/05

11/17/05

11/2/05

10/20/05

mg/l

9/29/05

9/7/05

8/24/05

8/10/05

7/13/05

6/1/05

5/18/05

4/6/05

1/20/05

1/5/05

12/21/04

12/8/04

11/24/04

10/15/04

Sixes River DO Comparison:
Water Year 2005 and Water Year 2006
2005 Water Year Sample Dates

30.00

25.00

20.00

15.00

10.00

5.00
2006 DO Conc

2005 DO Conc

0.00
DEQ STD 6.0 mg/l

2006 Water Year Sample Dates

Sixes River Turbidity Comparison:
Water Year 2005 and Water Year 2006

Water Year 2005 Grab Sample Dates

600.00

500.00

400.00

300.00

200.00

100.00

2006 Turbidity (Four Averages)

2005 Turbidity (Four Averages)

Water Year 2006 Sample Dates

36

9/25/06

9/5/06

8/22/06

8/9/06

7/26/06

6/29/06

6/1/06

5/16/06

4/28/06

4/13/06

3/28/06

3/13/06

pH

9/29/05

9/7/05

7/13/05

6/1/05

5/18/05

11/24/04

10/15/04

2.00

1.00
9/25/06

9/5/06

8/22/06

8/9/06

7/26/06

6/29/06

6/21/06

6/1/06

5/16/06

4/28/06

4/13/06

3/28/06

3/13/06

3/1/06

2/8/06

1/25/06

1/11/06

12/28/05

12/14/05

12/1/05

11/17/05

11/2/05

10/20/05

ms/cm

9/29/05

9/7/05

8/24/05

8/10/05

7/13/05

6/1/05

5/18/05

4/6/05

1/20/05

1/5/05

12/21/04

12/8/04

11/24/04

10/15/04

Sixes River SpCond Comparison:
Water Year 2005 and Water Year 2006
Water Year 2005 Sample Dates

0.12

0.10

0.08

0.06

0.04

0.02

0.00
2006 SpCond

2005 SpCond

Water Year 2006 Sample Dates

Sixes River pH:
Water Year 2005 and Water Year 2006

Water Year 2005 Sample Dates

9.00

8.00

7.00

6.00

5.00

4.00

3.00

2006 pH
2005 pH
DEQ Upper Limit: 8.5 pH
DEQ Lower Limit: 6.5 pH

0.00

Water Year 2006 Sample Dates

37

Sixes River Statistics: Water Year 2005
Statistics
Q3
Max
Median
Min
Q1
Mean
Std Dev

Temp °C
18.6
21.1
13.8
7.1
10.7
14.5
4.8

SpCond
0.1
0.1
0.1
0.1
0.1
0.1
0.0

DO mg/l
16.1
26.6
13.6
8.8
11.5
14.8
5.5

pH
6.9
7.2
6.7
6.5
6.6
6.8
0.3

Turbidity NTU
3.3
169.0
0.9
0.6
0.8
18.8
47.7

Sixes River Statistics: Water Year 2006
Statistics
Q3
Max
Median
Min
Q1
Mean
Std Dev

Temp °C
18.6
22.1
12.2
6.0
9.7
13.9
4.9

SpCond
0.1
0.1
0.1
0.0
0.1
0.1
0.0

DO mg/l
12.1
16.0
11.0
7.4
9.1
10.8
2.1

pH
7.5
7.8
7.4
7.0
7.4
7.4
0.2

Turbidity NTU
7.3
521.0
1.8
0.0
1.0
44.8
122.5

38

Sixes River Bacteria Data
The WQP began collecting water samples for microbiological analysis of E.coli and
Enterococcus at this site in April 2006. Because the data set for this parameter is
relatively small, no statistical analysis has been applied to these data. The following
tables list all bacteria data collected by our program for this site during water year 2006.
Our program currently compares single grab samples to ODEQ and EPA established
numeric criteria for Freshwaters and Estuarine Waters of either 1) no single sample
exceeding 406 E.coli organisms per 100 milliliters (406 MPN) or 2) The federal
Environmental Protection Agency (EPA) recommendation of the safe standard for
Enterococcus to be no more than 158 colony forming units (158 MPN) per 100 milliliters
of marine water. Of the sites currently monitored by our program, Kentuck Slough has
the highest levels of E. coli and Enterococcus. No samples collected by our program
during water year 2006 at this site have exceeded either of these criteria.
Sixes River E.coli Data: Water Year 2006
Sample Date
5/16/06
6/1/06
6/29/06
7/26/06
8/6/06
8/22/06
9/5/06
9/25/06

Analyte
E. coli.
E. coli.
E. coli.
E. coli.
E. coli.
E. coli.
E. coli.
E. coli.

MPN/100mL
Undiluted Sample
< 10.0
< 10.0
< 10.0
< 10.0
< 10.0
< 10.0
< 10.0
< 10.0

Sixes River Enterococcus Data: Water Year 2006
Sample Date
5/16/06
6/1/06
7/26/06
8/9/06
8/22/06
9/25/06

Analyte
Enterococci
Enterococci
Enterococci
Enterococci
Enterococci
Enterococci

MPN/100mL
Undiluted Sample
< 10.0
< 10.0
< 10.0
< 10.0
< 10.0
< 10.0

39

Issues of Tribal Concerns
Tribal water quality issues of concern continue to be the impairments listed on EPA’s
Clean Water Act 303 (d) Lists. These impairments are more than likely attributed to
multiple non-point sources contributions and land use practices within the watersheds.
Point source contributions to these impairments have not been assessed by the WQP. An
inventory of known point sources would be valuable information in addressing tribal
water quality issues. Detailed information on the types of impairments found at each
monitoring site can be found under the Site Description and Location section of this
report.

Conclusion
The completion of this report summarizes the hard work and long hours put in by tribal
staff to develop and implement a WQP that meets both Tribal needs and EPA program
requirements. The WQP continues to evolve to meet new program requirements found
within EPA’s Final Guidance on Awards of Grants to Indian Tribes under Section 106 of
the Clean Water Act for Fiscal Years 2007 and Beyond. With the continued support of
EPA, the WQP will continue to assess, protect, and improve water quality within our
ancestral watersheds.

40

---

Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/tribal%3Aconfederated_clusi%3A8802d01efc8340c5. Public record. Not legal advice.
