East Twin River Targeted Watershed Assessment, Kewaunee County TWA Plan

East Twin River Targeted Watershed Assessment, Kewaunee County

Project Title

East Twin River Targeted Watershed Assessment: A Water Quality Report to Restore Wisconsin Watersheds, 2020
East Twin River Watershed (TK02), HUC12: 070600050203, Monitored 2016

Study Purpose & Setting

Study Purpose
The purpose of this study was to assess overall conditions and identify areas of management in the East Twin River Watershed, focusing on the East Twin River and Unnamed Tributaries to the River as well as Krok Creek in Kewaunee County. In 2016, the Kewaunee County Board of Supervisors passed a resolution requesting DNR monitor this area, which is included in the Northeast Total Maximum Daily Load (TMDL) analysis and which hosts impaired waters with chlorides, ammonia, and chromium levels, including total phosphorus. The project results provide a contemporary status and insight into changes in water quality, habitat, and the biological communities in the watershed?s upper reaches. The NE TMDL webpage provides more information. The following are key deliverablesfrom this study:

- Streams in the watershed were monitored to understand their status.
- Presence and sources of impairments were identified.
- Monitoring priorities for future watershed work were identified.
- Management recommendations were developed.
- A presentation to the Kewaunee County Board of Supervisors on the condition

About the Watershed
The East Twin River Watershed is bordered on the east by Lake Michigan in Kewaunee and Manitowoc counties and is 117,493 acres in size. The watershed contains 314 miles of streams and river, 12,446 acres of lakes and 14,181 acres of wetlands. The watershed is dominated by agriculture and wetlands. Streams, ranging from intermittent to perennial, flow southeast through southern Kewaunee County and northern Manitowoc County to the City of Two Rivers where the river enters Lake Michigan. In this watershed there are 12.5 miles of trout water, 26.9 miles of warmwater sport fisheries, 13.6 miles of warmwater forage fisheries, 9.9 miles of limited forage fisheries, and 5 miles of limited aquatic life.

Recommendations

Conclusions and Recommendations This study assessed the condition of three UNTs, the East Twin River and Krok Creek for ecological impairment. Assessment data from 2017 were compared to prior surveys to determine if water quality conditions have changed and if streams are meeting water quality standards.

.All stream locations assessed exceed water quality criteria for phosphorus and should remain on the 303(d) impaired waters list.
Chloride, ammonia, and chromium levels in the streams are below impaired thresholds.
.Water temperature in UNT 3000213 exceed water quality standards and should remain on the impaired waters list.
.Ambient chronic toxicity was observed in UNT 3000213 on two occasions in 2017 (July and October). Chronic toxicity was observed on the East Twin River below the confluence with the UNT 3000211 (Station ID 104445) in June but is likely unrelated to UNT .3000213 since no toxicity was found in UNT 3000211 in June.
.Macroinvertebrate monitoring confirmed fair to good water quality conditions in the East Twin River and UNTs with a slight improvement over the 2011 assessment.
.Qualitative habitat assessments found mostly good to fair fish and aquatic life habitat available in Krok Creek, the East Twin River and all three UNTs.
.Watershed-wide non-point sources of nutrient and sediment contributions likely impact the water quality and aquatic life habitat in Krok Creek, the East Twin River and all three UNTs and should be controlled to the extent possible.
.The overall fish community in the Upper East Twin River watershed is in good to excellent condition.
.The natural community of the East Twin River at CTH J (Station ID 10008204) should be updated to reflect the current fish community structure of cool-warm headwater.
.The natural community of the East Twin River at Krok Road bridge (Station ID 10020812) should be updated to reflect the current fish community structure of cool-cold headwater.
.The natural community of the UNT 3000211 at Sleepy Hollow Road (Station ID 10029040) should be updated to reflect the current fish community structure of cool-warm headwater.

Resources

Biological Communities and Water Quality
Streams in this watershed have impairments from total phosphorus, but the physical habitat and biological communities were meeting he designated uses. Assessment data from 2017 were compared to previous years to determine if water resource conditions changed. An industrial manufacturing facility discharges treated wastewater to the UNT 3000213 to the East Twin River above Cherneyville Road in Kewaunee County. This tributary flows into the East Twin River just downstream of Hwy 29. Previous studies include surveys of the East Twin River (WBIC 84000), Unnamed Tributaries (UNT) to the East Twin River (WBIC 3000211, 3000212, and 3000213) and Krok Creek (WBIC 86700) were conducted and previous studies ( 2001, 2008, 2009, 2011/2012, and 2015) and water chemistry and temperature data collected in 2011/2012 and 2017.

Natural Communities

Fish Natural Communities
.Based on fish survey data available, the modeled and verified natural community (Table 8) of the East Twin River was a cool-cold headwater at both Townline Road (Station ID 10008206) and Krok Road ï¿½Ditchï¿½ (Station ID 10030630). The modeled natural community at CTH J (Station ID 10008204) was warm headwater but verified as a cool-warm headwater based on the fish assemblage. The modeled natural community at Krok Road bridge (Station ID 10020812) was cool-warm headwater but verified as cool-cold headwater.
.UNT 3000212 at Cherneyville Road (Station ID 10029041) was modeled as a macroinvertebrate stream but due to lack of fish no verification was completed.
.UNT 3000211 at Sleepy Hollow Road (Station ID 10029040) was modeled as a cool-cold headwater but was verified as a cool-warm headwater based on the fish community.

Methods & Procedures

This study involved the collection of fish community, macroinvertebrate, water chemistry, and qualitative habitat data at several sites in the watershed. The upper reaches of the East Twin River, Unnamed Tributaries, and Krok Creek were monitored at 13 locations. Parameters included habitat assessments, aquatic toxicity (WET), continuous water temperature, invertebrates, water chemistry grab samples, and fish surveys. Habitat assessments were conducted at all 13 locations one time in the summer of 2017. Aquatic toxicity samples were collected at 5 locations at the same time the water chemistry samples are collected. Continuous temperature monitors (HOBO's) will be installed at 6 sites for the entire 2017 summer. Macroinvertebrates were collected at 9 locations in fall 2017. Water samples were collected to analyze chloride, total phosphorus, and ammonia from monthly samples, May through October, at 8 sites. Fish surveys were conducted by DNR Fisheries staff.

Monitoring included
. Six monthly water chemistry samples during the growing season for total phosphorus, chloride, and ammonia.
. Continuous temperature meters at seven locations during the growing season.
. Quantitative and qualitative habitat assessments.
. Fish surveys at five locations.
. Macroinvertebrate samples at nine locations.

Monitored Streams
Studied streams include the East Twin River (WBIC 84000), Unnamed Tributaries (UNT) to the East Twin River (WBIC 3000211, 3000212, and 3000213), Krok Creek (WBIC 86700), and East Twin River at Krok Road Ditch (Station ID 10030630). Previous evaluations of conditions of the same streams in the Upper East Twin River watershed?s current report were conducted in 2001, 2008, 2009, 2011/2012, and 2015.

Methods, Equipment and Quality Assurance
Monitoring was conducted at several locations along the reaches of the East Twin River and the Unnamed Tributaries to the East Twin River (Table 2) following DNR Field Procedures Manuals and guidelines for proper collection and preservation techniques and included the following assessments.

Water Chemistry Sampling
Grab samples were collected once per month throughout the growing season (May through October) at four sites in the East Twin River, one site in Krok Creek, one site in the unnamed stream (3000213), and two sites in the unnamed stream (3000211). Water sampling dates were selected in the spring for all sampling events to eliminate bias. Samples were sent to be analyzed for total phosphorus, ammonia, and chloride contents at the Wisconsin State Laboratory of Hygiene. One additional sample was taken from Unnamed Tributary (300212) and sent to be analyzed for chromium at the Wisconsin State Laboratory of Hygiene.
.Guidelines and Procedures for Surface Water Grab Sampling (Dec. 2005 Version 3)

Continuous Temperature
Water temperature data loggers (HOBO brand) were placed in East Twin River, Unnamed Tributary to East Twin River (3000213 and 3000211), and Krok Creek from May to October 2017. The loggers recorded temperature every hour.
.Guidelines and Standard Procedures for Continuous Temperature Monitoring Wisconsin DNR May 2004 (Version 1)
Ambient toxicity testing
Grab Samples were collected throughout the growing season (May through October) at two locations on the East Twin River and three locations on the Unnamed Tributary. The samples were delivered to the Wisconsin State Laboratory of Hygiene to be tested for acute and chronic toxicity using zooplankton, minnows, and algae.

Macroinvertebrate Evaluation
Macroinvertebrate samples were obtained by kick sampling and collecting using a D-frame net at nine monitoring locations along the reaches of the East Twin River and the Unnamed Tributaries to the East Twin River. Samples were preserved and sent to the University of Wisconsin-Stevens Point for analyses. The Hilsenhoff biotic Index (HBI) and Macroinvertebrate Indices of Biotic Integrity (M-IBI) were calculated for each sample collected. HBI is a measure of organic pollution with scores from 0 (excellent) to 10 (very poor). M-IBI uses several metrics to assess overall stream conditions with scores from 10 (excellent) to 0 (poor).
. Guidelines for Collecting Macroinvertebrate Samples in Wadeable Streams
. Wadeable Macroinvertebrate Field Data Report Form 3200-081 (R 08/14)

Habitat Evaluation
Aquatic life habitat was evaluated at several sites along the East Twin River and the Unnamed Tributaries to the East Twin River and recorded on the Wadeable Stream Qualitative Fish Habitat form. The host of variables measured included depth and width parameters, bottom characteristics, plant growth, percent shading from vegetation, fish cover, streambank erosion and surrounding land use. A score based on habitat evaluation of 100 (excellent) to 0 (poor) was assigned to each location assessed.
. Guidelines for Qualitative Physical Habitat Evaluation of Wadeable Streams
. Qualitative Habitat Rating less that 10m Form (3600-532A) (R 6/07)

Fish Assemblage
The method for fish collection was conducted by electroshocking a section of stream with a minimum station length of 35 times the mean stream width (Lyons, 1992). A backpack shocker with a single probe was used at all five of the locations surveyed. Fish were identified and the number of each species present was tallied. The Index of Biotic Integrity (F-IMI) based on the fish community at each sampling location was calculated. F-IBI scores range from 100 (excellent) to 0 (poor) which relates community structure to community health to water quality. The fisheries assemblage was collected with the following methods:
. Wadeable Stream Fish Community Evaluation Form 3600-230 (R 7/00)
. Guidelines for Assessing Fish Communities of Wadeable Streams in Wisconsin

Study Results

In this East Twin River TWA study, the objective of choosing the sampling locations was to quantify stream health in the overall watershed and to measure any potential impact to stream health. Unnamed tributary (UNT) 3000213 flows into UNT 3000212 then 3000211 and ultimately the East Twin River. Several monitoring stations were selected on the UNTs with the furthest downstream site on UNT 3000211 at its confluence with the East Twin River near Hwy 29. Two stations on the East Twin River (Station IDs 10008206 and 10034445) were selected upstream of this confluence to monitor background reference conditions. In addition, monitoring Station ID 10008203 on Krok Creek provided an additional reference station in a nearby tributary of the East Twin River. Monitoring station ID 104445 on the East Twin River was established downstream of the outlet of UNT 3000211 to detect any possible impacts from the tributary. Finally, a monitoring station about 3.7 miles downstream of the UNT outlet was monitored (Station ID 10008204) quantifying any potential widespread impact of this tributary on the East Twin River.

Along with evaluating existing data, current data collected in 2017 were assessed against the Wisconsin 2018 Consolidated Assessment and Listing Methodology (WisCALM, 2017) guidance to determine if the streams are meeting water quality standards. The streams surveyed during this project are currently assessed against standards relating to the assigned fish and aquatic life use designations as shown in Table 1. Fish and Aquatic Life use categories evaluated with this project include Cold Water Community (COLD) and Default Fish and Aquatic Life (DFAL). Currently in WisCALM, streams and rivers are being evaluated for placement in a revised aquatic life use classification system, in which the new fish and aquatic life use subclasses are referred to as Natural Communities. Natural community classification is important when evaluating the Fish Index of Biotic Integrity (F-IBI). Natural communities in the Upper East Twin River study area include macroinvertebrate, cool-cold headwater, and cool-warm headwater streams.

Water quality criteria thresholds for cold water and DFAL uses are specified in NR 102 and WisCALM as follows:
.Dissolved oxygen: cold water <6 mg/l, DFAL <5 mg/l.
.Water temperature: cold water >73?F, DFAL >86?F.
.Chloride: acute toxicity >757 mg/l, chronic toxicity >395 mg/l.
.Total phosphorus: >0.075 mg/l.

The headwaters of the East Twin River down to CTH B are currently on the Clean Water Act Section 303(d) list of impaired waters for phosphorus. The UNTs 3000211, 3000212 and 3000213 in their entirety are also on the impaired waters list for phosphorus. UNT 3000213 is on the impaired waters list for water temperature.

Water Chemistry - Total Phosphorus
As specified in NR 102 of the Wisconsin Administrative Code, the total phosphorus criterion of 0.075 mg/l is established for the unnamed
tributaries, East Twin River and Krok Creek. The protocol for impairment decisions requires six monthly samples to be collected between
May and October. The department?s listing methodology for impaired waters (WDNR, 2017) lists waters where the median concentration
and 90% confidence interval values exceeds 0.075 mg/l on wadeable streams.

As shown in Figure 9, the median and 90% confidence interval values for total phosphorus at all monitoring locations in 2011 clearly
exceed the 0.075 mg/l impairment threshold. In 2017, all stations exceeded the criteria except for the East Twin River at Townline Road
(Station ID 10008206), where the lower 90% confidence interval was just below 0.075 mg/l.

The East Twin River is currently listed as impaired from its headwaters down to CTH B for total phosphorus. Krok Creek and the UNTs
3000211, 3000212 and 3000213 are also listed as impaired for phosphorus.

Water Chemistry - Chloride
The protocol for impairment decisions established in 2018 WisCALM for chloride requires at least two values within a 3-year period. Six
monthly chloride samples were collected at the same time the phosphorus samples were collected. The criterion for chronic toxicity is 395
mg/l and for acute toxicity it is 757 mg/l.

As shown in Figure 10, none of the chloride samples collected on the UNTs 3000213 and 3000211, the East Twin River or Krok Creek
exceeded established thresholds for chronic toxicity in 2011/2012 or 2017. Although they did not exceed any thresholds, it is apparent that
higher concentrations of chloride are observed in the UNTs compared to the reference streams.

Water Chemistry - Ammonia
Figure 11 displays total ammonia results from 2017. Six monthly samples were collected at the same locations and times as the other water samples. Ammonia was not collected in 2011 and 2012. The data suggest none of the ammonia sample results were high enough to cause ammonia toxicity to aquatic life according to the methods of the Environmental Protection Agency (2013) and Wisconsin Administrative Code NR105.

Water Chemistry - Chromium
Six monthly water samples were collected at one location on UNT 3000213 (Station ID 10033637). Three sampling events did not detect chromium but the other three samples document levels slightly above the detection limit of 1.0 ug/l (1.48, 1.32, and 1.7 ug/l). As specified in Wisconsin Administrative Code NR 105, the chronic criterion for chromium is 326 ug/l. Thus, the low levels detected would not be considered toxic to aquatic life.

Continuous Water Temperature
Water temperatures were logged hourly at three stations on the East Twin River and one each on UNTs 3000211 and 3000213 in 2011. The same stations plus the addition of one on Krok Creek were monitored in 2017. Average daily temperature throughout each field season by Station ID are summarized in Figure 13 for 2011 data and in Figure 12 for 2017 data.

except for the furthest downstream station at CTH J (Station ID 10008204). The East Twin River at CTH J exceeded water quality criteria in July and August of 2011, however in 2017, water quality criteria were met in all months.

Water temperature in UNT 3000213 at the Cherneyville Road (Station ID 10033637) exceeded the DFAL temperature criteria (maximum summer temperature of 86?F) for all months monitored in both 2011 and 2017 as shown in Figure 8. Water temperature approximately 2 miles downstream in UNT 3000211 at Hrabik Road (Station ID 10030304) met DFAL temperature criteria for all months monitored.

Ambient Toxicity Testing
Fathead Minnow (Pimephales promelas) Toxicity:
Acute Toxicity:
. 2011: No acute toxicity observed at any sampling sites.
. 2017: No acute toxicity observed at any sampling sites.

Chronic Toxicity:
. 2011: Chronic toxicity was found in UNT 3000213 Cherneyville Road (Station ID
10033637) in May and June of that year.
. 2017: No chronic toxicity as indicated by statistical differences between fish growth in surface water samples and controls, was found at any of the sites.
.However, on two occasions survival and growth was noticeably lower in the surface water than in control treatments in the chronic fathead minnow toxicity test.
. In June, survival in the sample collected in the UNT 3000213 (Station ID 10033637) was 15% lower than the control. In September, survival at the same site was 21% lower than the control. Growth was also lower than at any of the other sites on both of these dates, although these differences were not found to be statistically significant.

Water Flea (Ceriodaphnia dubia) Toxicity:
Acute Toxicity:
. 2011: Acute toxicity was observed in May at UNT 3000213, Cherneyville Road (Station ID 10033637).
. 2017: No acute toxicity observed at any sampling sites.

Chronic Toxicity:
. 2011: Chronic toxicity was found in UNT 3000213, Cherneyville Road (Station ID 10033637) and in UNT 3000211, Hrabik Road (Station ID 10030304) in May. Chronic toxicity was also found in UNT 3000211 at the stream mouth (Station ID 1033921), and in the East Twin River below this confluence (Station ID 104445), and at the Townline
Road site (Station ID 10008206) in July.
. 2017: Chronic toxicity was found in two samples collected during the field season. Reproduction was found to be significantly lower in June at the East Twin River below the confluence of UNT 3000211 (Station ID 104445) and at the UNT 3000213 (Station ID 10033637) in October. The October sample showed both significantly lower
reproduction and lowered survival (20% lower than the control).

Green Algae (Selenastrum capricornutum) Toxicity:
Chronic Toxicity:
Tables associated with toxicity measurements can be found in Appendix B.
. 2011: Chronic toxicity was found at UNT 3000213 (Station ID 10033637) and at the UNT 3000211 at Hrabik Road (Station ID 10030304) in June. Chronic toxicity was also found at the East Twin River below UNT 3000211 at Station ID 104445 in July, however, the reduction in growth of this sample was below the level of concern normally used for algae tests (50% of the control).
. 2017: UNT 3000213 (Station ID 10033637) showed noticeably lower green algae growth in the July and August samples, although only the July sample was found to be statistically different from the control.

Macroinvertebrates
Macroinvertebrate samples were collected at multiple sites in the project area to calculate a Macroinvertebrate Index of Biological Integrity (M-IBI). The M-IBI is composed of various metrics used to interpret macroinvertebrate data. 2017 M-IBI categorical results for the East Twin River and UNT sites were either the same as 2011 or better as shown in Table 6.
. The East Twin River at CTH F (Station ID 10034445) went from poor in 2011 to good in 2017.
. At Krok Road ?Ditch? (Station ID 10030630) M-IBI went from fair to good.
. The other three sites remained the same as either fair or good.
. Krok Creek (Station ID 10008203) was also assessed in 2017 and received a good M-IBI rating.
. UNT 3000212 Cherneyville Road (Station ID 10029041) received poor M-IBI scores in 2008 and 2011 but a fair score in 2017.
. UNT 3000211 at Sleepy Hollow Road (Station ID 10029040) and Hrabik Road (Station ID 10030304) received a fair M-IBI scores all years assessed.

Habitat Assessments
Aquatic habitat was evaluated at monitoring stations in the project area as shown in Table 7. Habitat values ranged from poor to good in 2017. In general, habitat values in the East Twin River and UNTs were similar or slightly lower in 2017 compared to 2011. The East Twin River at CTH F went from a good rating in 2011 to a poor rating in 2017. Habitat assessments were completed at only two locations on the UNT in 2008 and both received a fair rating.

Fish Condition
Fish Index of biological integrity (F-IBI) scores indicate the East Twin River at Townline Road (Station ID 10008206) was in good condition (in 2017). In previous years, fish IBI scores were fair to excellent.
In 2017 F-IBI score in the East Twin River at Krok Road Ditch (Station ID 10030630) was excellent and had also received excellent to fair scores in previous surveys.

A fish survey conducted in the East Twin River at Krok Road bridge (Station ID 10020812) received a good rating in 2015. F-IBI scores were excellent all years surveyed at CTH J (Station ID 10008204).

F-IBI scores rated the UNT 3000211 at Sleepy Hollow Road (Station ID 10029040) as good in 2017 and excellent in 2008. Surveys in 2008 and 2017 did not result in enough fish captured at Cherneyville Road east crossing (Station ID 10029041) to calculate an F-IBI score.

Study Discussion

This study assessed the condition of the East Twin River, its unnamed tributaries and Krok Creek for ecological status. Overall stream health was determined by evaluating chemical, physical and biological parameters against Wisconsin Assessment and Listing Methodology Guidelines. Assessment data from 2017 were compared to prior survey data to determine if water quality conditions have changed and if streams are meeting water quality standards.

Impairment Status
Sampling data confirm that the East Twin River, Krok Creek and the unnamed tributaries 3000212, 3000213 and 3000211 in their entirety are on the impaired waters list for phosphorus. Chloride, ammonia and chromium concentrations all met water quality standards. Based off the data collected, these water quality constituents do not pose a threat to aquatic life in the streams assessed. Despite non-point source influences throughout the entire watershed, the phosphorus and chloride concentrations were the highest in UNT 3000213.

Water Temperature
Water temperature of the East Twin River at all stations except at CTH J met cold water quality criteria. East Twin River at CTH J (Station ID 10008204) exceeded water quality criteria in July and August of 2011, however in 2017, the water quality criteria were met in all months. During July and August of 2011 when cold water criteria for temperature was not met, the daily maximum temperature was exceeded 12 and 8 days respectively by 0.7-3.3?C. Taking into consideration the accuracy of +/- 0.53?C of the continuous data collection meters, it can only be assumed that 9 and 2 days respectively did not meet the cold criteria for temperature. This leaves only the month of July in 2011 that did not fully meet cold water criteria for temperature on the East Twin River at CTH J. This single month of failing to meet cold water criteria could be sufficient to propose this segment of the East Twin River to be listed as impaired for temperature. However, this is not recommended. Based on knowledge of this stream and its location at the lower reaches of the East Twin River Class II trout waters, it is likely this segment is naturally on the transition between a cold and warm classification.

Water monitoring data confirm that UNT 3000213 clearly exceed water quality standards for temperature and should remain on the impaired waters list. Temperatures at Cherneyville Road (Station ID 10033637) exceeded the DFAL temperature criteria for all months monitored in both 2011 and 2017. Water temperature approximately 2 miles downstream in UNT 3000211 at Hrabik Road (Station ID 10030304) met DFAL temperature criteria for all months monitored.
Ambient acute toxicity was not observed in 2017 at any station monitored although chronic toxicity was observed in the UNT 3000213 (Station ID 10033637) in July and October and in the East Twin River below Hwy 29 (Station ID 104445) in June.

In comparison, acute toxicity was observed in 2011 in UNT 3000213 (Station ID 10033637) in May. Chronic toxicity was observed in UNT 3000213 in May and June and in the UNT 3000211, Hrabik Road (Station ID 10030304) in May. However, chronic toxicity was also observed in the East Twin River at Townline Road (Station ID 10008206), below Hwy 29 (Station ID 104445), and at the mouth of the UNT 3000211 (Station ID 10033921) in July indicating possible larger-scale watershed problems.

The macroinvertebrate communities indicate that water quality conditions in the East Twin River is in fair to good condition both upstream and downstream from the confluence of UNT 3000211. The macroinvertebrate communities indicate fair to poor water quality condition in the upper reaches of UNT 3000212 at Cherneyville Road (Station ID 10029041) and fair conditions at two sites on UNT 3000211 at Sleepy Hollow Road (Station ID 10029040) and Hrabik Road (Station ID 10030304). Substrate type and watershed-wide non-point sources of nutrient and sediment contributions likely impact the water quality and macroinvertebrate habitat in both the East Twin River and the UNTs.

Blue Iris Environmental, Inc. conducted a cursory evaluation of the stream inhabitants of the East Twin River at three locations on July 1, 2009 (West, 2009). The full survey report is provided in Appendix C. Although a variety of taxa were noted at each of the three locations and ranged from abundant to present, the survey technique used was not meant to create a M-IBI value and therefore it is not possible to rate the overall stream health based on the 2009 results. The taxa Plecoptera (Stonefly) was observed in this survey and in 2017 by the WDNR at the Krok Road site while Ephemeroptera (mayfly) were only observed in 2009 at that site. Stoneflies are considered intolerant to pollution.

Fish and aquatic life habitat was assessed at multiple locations in the watershed. Qualitative habitat is rated based on riparian buffer width, amount of bank erosion, percent of pools, riffle and runs, substrate type and cover for adult fish. These metrics combined give an overall score for available habitat. In general, habitat in the East Twin River can be considered in good condition. At Church Road (Station ID 10020787) the extensive amount of fine sediment and lack of riffles limit a variety of habitat and therefore it only received a fair score. East Twin River at CTH F (Station ID 10008204) received a poor score since the stream is extremely small and shallow at this location. A previous good score in 2011 showed deeper water and less fine sediment accumulation.
The fish indices of biological integrity (F-IBI) and the macroinvertebrate indices of biological integrity (M-IBI) were used to determine whether current water quality conditions support the Fish and Aquatic Life designated uses.

Natural communities are defined for streams and rivers using model-predicted flow and temperature ranges associated with specific fish and/or macroinvertebrate communities. Segments are initially classified into natural communities based on landscape-scale statistical models that predict long-term flows and temperatures from watershed characteristics such as watershed size, surficial and bedrock geology, topography, climate, and land cover. These predictions represent the realistic potential Natural Community of the segment under current land-cover and climate conditions in the absence of significant site-specific human impacts, such as local riparian degradation. Correct natural community classification is currently a critical step in applying the correct F-IBI to evaluate water quality influences on the fish community and to provide an accurate bio-assessment. Misclassified streams could be assessed with the incorrect IBI, and their environmental condition may be misjudged. The Department has a guidance document that can correct misclassifications (Lyons, 2013). The procedures were followed to correctly assign a natural community at all fish surveys stations so the correct application of the IBI was used.

The East Twin River from its headwaters downstream towards CTH J aligns with a cool cold headwater stream classification in that it is a small perennial stream with cool to cold summer water temperatures. Coldwater fish range from absent to abundant, transitional fish from common to dominant, and warmwater fish from absent to common. Small-stream fish range from very common to dominant (50-100% of individuals), medium-stream fish from absent to very common (0-50% of individuals), and large-river fish from absent to uncommon (0-10% of individuals).

As the East Twin River approaches CTH J the stream begins a transition from a cool-cold headwater towards a cool-warm headwater stream with cool to warm summer temperatures. Coldwater fish range from absent to common, transitional fish from common to dominant, and warmwater fish from absent to abundant. Small-stream fish range from very common to dominant, medium-stream fish from absent to very common, and large-river fish from absent to uncommon. The natural community verification of the East Twin River at CTH J can place the stream in either a cool-cold headwater or a cool-warm headwater stream based on the percentage of coldwater and warmwater fish species observed. The percentage catch of coldwater species is outside the range for a cool-warm headwater stream and the percentage catch of warmwater species is outside the range of a cold-cold headwater stream. Based upon available fish data, classification as a Class II trout stream, and continuous water temperature data the East Twin River at CTH J is best represented and is verified as a cool-warm headwater stream.

UNT 3000211 at Sleepy Hollow Road (Station ID 10029040) has a verified natural community classification as a cool-warm headwater stream. The modeled natural community classification as a cool-cold headwater stream is likely inaccurate based on fish surveys conducted in 2008 and 2017. The fish community in this stream aligns with a cool-warm headwater stream. In any given year, the number of coldwater species may range from absent to common in these headwater streams. They are differentiated by the percent of the overall catch consisting of coldwater, transitional, and warm water species. In 2008, four mottled sculpin, a cold-water intolerant species, were observed and made up 2% of the total catch. In 2017, mottled sculpin were absent. The remainder of the catch in both years was almost entirely transitional species which are common to abundant in both cool-warm and cool-cold headwater streams. It is also important to note that a high percentage of species captured in both years were tolerant of environmental degradation and outside the expected range for either stream community. This is a significant indicator when there is an absence of intolerant species observed in surveys. However, in both years, intolerant species were observed (mottled sculpin or redside dace).
The capture of the species in this survey allows a new natural community classification to be assigned and indicates human-caused impacts are likely not a significant factor in the overall fish community structure. UNT 3000212 at Cherneyville Road (Station ID 10029041) was classified as a macroinvertebrate stream which is consistent with surveys conducted in 2008 and 2017 in that it had a low abundance of fish. These macroinvertebrate streams are very small, almost always intermittent streams with a wide range of summer temperatures. No or few fish (< 25 per 100 m of wetted length) are present, but a variety of aquatic invertebrates may be common, at least seasonally. M-IBI in 2017 supported this by receiving a fair rating at this location. The low abundance of fish surveyed on this site does not indicate an aquatic life impairment, only that this stream is not conducive to supporting a fish community throughout the year and that a macroinvertebrate stream classification system is justified.

The overall fish community in the Upper East Twin River watershed is in good to excellent condition. Two key metrics that provide insight into the index include number of intolerant species and number of tolerant species. Up to four species intolerant of environmental degradation have been captured in surveys throughout the years surveyed with no decline in abundance or elimination from sites. The intolerant species observed include brook trout, mottled sculpin, reside dace, and brook lamprey. Of these, both the brook trout and mottled sculpin are considered coldwater species. It is also important to note that throughout all survey stations and years, a degraded tolerant fish community was not observed indicating human based influence of degradation did not significantly alter the fish community assemblage.
In 2006, a significant fish kill of multiple species occurred from a wastewater treatment plant failure at the current location of Agropur, Inc. (Trega Foods) facility. This kill was documented in the East Twin River from the confluence of UNT 3000211 downstream to the confluence of Krok Creek. No pre-fish kill data exists for this stretch of the East Twin River but 84 dead brook trout ranging in size from 4-14? were collected representing 3+ year classes of brook trout. This generally represents a catch per effort mile of 41.4 through this stretch of river. Post fish-kill surveys were conducted at Krok Road ?Ditch? (Station ID 10030630) and zero brook trout were captured 2009 and 2011. In 2015, one 8.2? brook trout was captured representing one year class. In 2017, three brook trout ranging in size between 2.5-7.9? were captured representing two year classes. The catch per effort mile for these surveys were 15.3 and 48.3 respectively. The current brook trout size structure and year class distribution may indicate that the population has not fully recovered, however it does appear based on population density that the brook trout population is on a track for recovery. Furthermore, based on the F-IBI ratings of good to excellent, it appears the overall fish community has recovered from the fish kill of 2006. Note that the additional surveys above and beyond the normal DNR fish survey schedule was conducted to assess brook trout population recovery from this incident.

Management Recommendations

This study was designed to create an updated assessment of the overall conditions of the East Twin River Watershed, including
assessments of the condition of three Unnamed Tributaries (UNTs), the East Twin River and Krok Creek for ecological impairment.
Assessment data from 2017 were compared to prior surveys to determine if water quality conditions have changed and if streams are meeting water quality standards. This information was shared with county experts to provide management recommendations for local activities including grants. The following are conclusions and recommendations from the 2017 assessment report:
All stream locations assessed exceed water quality criteria for phosphorus and should remain on the 303(d) impaired waters list.
Chloride, ammonia, and chromium levels in the streams are below impaired thresholds.

1. Water temperature in UNT 3000213 exceed water quality standards and should remain on the impaired waters list. Ambient chronic toxicity was observed in UNT 3000213 on two occasions in 2017 (July and October).
2. Chronic toxicity was observed on the East Twin River below the confluence with the UNT 3000211 (Station ID 104445) in June but is likely unrelated to UNT 3000213 since no toxicity was found in UNT 3000211 in June.
3. Macroinvertebrate monitoring confirmed fair to good water quality conditions in the East Twin River and UNTs with a slight
improvement over the 2011 assessment.
4. Qualitative habitat assessments found mostly good to fair fish and aquatic life habitat available in Krok Creek, the East Twin River and all three UNTs.
5. Watershed-wide non-point sources of nutrient and sediment contributions likely impact the water quality and aquatic life habitat in Krok Creek, the East Twin River and all three UNTs and should be controlled to the extent possible.
6. The overall fish community in the Upper East Twin River watershed is in good to excellent condition.
7. The natural community of the East Twin River at CTH J (Station ID 10008204) should be updated to reflect the current fish
community structure of cool-warm headwater.
8. The natural community of the East Twin River at Krok Road bridge (Station ID 10020812) should be updated to reflect the current fish community structure of cool-cold headwater.
9. The natural community of the UNT 3000211 at Sleepy Hollow Road (Station ID 10029040) should be updated to reflect the current fish community structure of cool-warm headwater.

Management Recommendations

Monitoring and Planning

Water Quality Plan Goals
The purpose of this study was to determine the contemporary status and potential recent changes in water quality, habitat, and the biological communities in the upper reaches of the East Twin River watershed. This plan is designed to present monitoring study results, identify issues, or concerns in the area found during the project, and to make recommendations to improve or protect water quality consistent with Clean Water Act guidelines and state water quality standards.

Abbreviations

AEL: Aquatic Entomology Laboratory at UW ? Stevens Point: the primary laboratory for analysis of macroinvertebrate taxonomy in the State of Wisconsin.

BMP: Best Management Practice. A land management practice used to prevent or reduce nonpoint source pollution such as runoff, total suspended solids, or excess nutrients.

DATCP: Wisconsin Department of Agriculture, Trade and Consumer Protection ? the state agency in partnership with DNR responsible for a variety of land and water related programs.

DNR: Department of Natural Resources. Wisconsin Department of Natural Resources is an agency of the State of Wisconsin created to preserve, protect, manage, and support natural resources.

END: Endangered Species - Wisconsin species designated as rare or unique due to proximity to the farthest extent of their natural range or due to anthropogenic deleterious impacts on the landscape or both.

ERW: Exceptional Resource Water- Wisconsin?s designation under state water quality standards to waters with exceptional quality and which may be provided a higher level of protection through various programs and processes.

FMDB: Fisheries Management Database ? or Fish Database ? the state?s repository for fish taxonomy and auto-calculated metrics involving fish assemblage condition and related.

FIBI: Fish Index of biological integrity (Fish IBI). An Index of Biological Integrity (IBI) is a scientific tool used to gauge water condition based on biological data. Results indicate condition and provide insight into potential degradation sources. In Wisconsin, specific fish IBI tools are developed for specific natural communities. Therefore, biologists must review and confirm the natural community to use the correct fish IBI tool.

HUC: Hydrologic Unit Code. A sequence of numbers that represent one of a series of nested hydrologic catchments delineated by a consortium of agencies including USGS, USFS, and Wisconsin DNR.

MIBI: Macroinvertebrate Index of biological integrity. The mIBI is the primary tool used to assess stream macroinvertebrate community condition.
NC: Natural Community. A system of categorizing water based on inherent physical, hydrologic, and biological components. Streams and Lakes have uniquely derived systems that result in specific natural community designations for each lake and river segment in the state. These designations dictate the appropriate assessment tools which improves the condition result, reflecting detailed nuances reflecting the modeling and analysis work foundational to the assessment systems.

Monitoring Seq. No. Monitoring sequence number refers to a unique identification code generated by the Surface Water Integrated

Monitoring System (SWIMS), which holds much of the state?s water quality monitoring data except for fisheries taxonomy and habitat data.

MDM: Maximum Daily Averages ? maximum daily average is a calculated metric that may be used for temperature, dissolved oxygen and related chemistry parameters to characterize water condition.

NC: Natural Community. A system of categorizing water based on inherent physical, hydrologic, and biological components. Streams and Lakes have uniquely derived systems that result in specific natural community designations for each lake and river segment in the state. These designations dictate the appropriate assessment tools which improves the condition result, reflecting detailed nuances reflecting the modeling and analysis work foundational to the assessment systems.

mg/L: milligrams per liter - a volumetric measure typically used in chemistry analysis characterizations.

NOAA: National Oceanic and Atmospheric Administration ? a federal agency responsible for water / aquatic related activities involve the open waters, seas and Great Lakes.

ND: No detection ? a term used typically in analytical settings to identify when a parameter or chemical constituent was not present at levels higher than the limit of detection.

NRCS: USDA Natural Resources Conservation Service

ORW: Outstanding Resource Water- Wisconsin?s designation under state water quality standards to waters with outstanding quality and which may be provided a higher level of protection through various programs and processes.

SC: Species of Special Concern- species designated as special concern due to proximity to the farthest extent of their natural range or due to anthropogenic deleterious impacts on the landscape, or both.

SWIMS ID. Surface Water Integrated Monitoring System (SWIMS) identification number is the unique monitoring station identification number for the location of monitoring data.

TDP: Total Dissolved Phosphorus ? an analyzed chemistry parameter collected in aquatic systems positively correlated with excess productivity and eutrophication in Wisconsin waters.

TMDL: Total Maximum Daily Load ? a technical report required for impaired waters Clean Water Act. TMDLs identify sources, sinks and impairments associated with the pollutant causing documented impairments.

TP: Total Phosphorus - an analyzed chemical parameter collected in aquatic systems frequently positively correlated with excess productivity and eutrophication in many of Wisconsin?s waters.

TWA: Targeted Watershed Assessment. A monitoring study design centered on catchments or watersheds that uses a blend of geometric study design and targeted site selection to gather baseline data and additional collection work for unique and site-specific concerns for complex environmental questions including effectiveness monitoring of management actions, evaluation surveys for site specific criteria or permits, protection projects, and generalized watershed planning studies.

TSS: Total suspended solids ? an analyzed physical parameter collected in aquatic systems that is frequently positively correlated with excess productivity, reduced water clarity, reduced dissolved oxygen and degraded biological communities.

WATERS ID. The Waterbody Assessment, Tracking, and Electronic Reporting System Identification Code. The WATERS ID is a unique numerical sequence number assigned by the WATERS system, also known as ?Assessment Unit ID code.? This code is used to identify unique stream segments or lakes assessed and stored in the WATERS system.

WBIC: Water Body Identification Code. WDNR?s unique identification codes assigned to water features in the state. The lines and information allow the user to execute spatial and tabular queries about the data, make maps, and perform flow analysis and network traces.

WSLH: Wisconsin State Laboratory of Hygiene? the state?s certified laboratory that provides a wide range of analytical services including toxicology, chemistry, and data sharing.

WQC: Water quality criteria ? a component of Wisconsin?s water quality standards that provide numerical endpoints for specific chemical, physical, and biological constituents.