Brown s Creek Impaired Biota TMDL Phase II

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1 PROJECT WORKPLAN TMDL Summary and Cover Sheet Project Name: Brown s Creek Impaired Biota TMDL Phase II Project and Budget Period: Project Sponsor: November 1, 2007 August 31, 2009 Project Representatives: Jay Riggs, District Manager Christopher Klucas St. Croix Basin Coordinator Minnesota Pollution Control Agency 520 Lafayette Road St. Paul, MN phone: fax: christopher.klucas@pca.state.mn.us Impaired Reach or Reaches: Reach Description AUID Impairmen t T30 R20 S18, west line to St. Croix River Brown s Creek Brown s Creek T30 R21 S12, north line to T30 R21 S13, east line Pollutant or Stressor Aquatic life Lack of a coldwater assemblage Aquatic life Lack of a coldwater assemblage Aquatic macroinvertebrate bioassessments Target Start/End 2006/ /2009 Phase II of the Brown s Creek Biological TMDL Stressor Identification Phase II 1

2 BROWN S CREEK BIOLOGICAL TMDL STRESSOR IDENTIFICATION Project Approach During the Phase I Stressor Identification Process, significant data was collected from Manning Avenue North to 110 th Street from the time period of April thru June While this data has been extremely useful to help characterize this reach of Brown s Creek, the scope of the project has changed to include the entire stretch of Brown s Creek from 110 th Street to the St. Croix River. The reason for this change of scope is due to the fact that an error was found in the MPCA rule that lists the assessment units for Brown s Creek and as such, the MPCA is proposing to change the assessment unit and hence the 303(d) listing for Brown s Creek. Where previously the creek was listed as impaired due to a low Index of Biotic Integrity score based on class 2B criteria, the entire trout stream below 110th to the St. Croix River will now be impaired based on class 2A criteria and the stream will be listed as being impaired due to a lack of cold waters fisheries. The remaining previous impairment for macroinvertebrates will remain unchanged but will extend to the St. Croix River With the new change in scope, this updated work plan focuses on extending the previous Stressor Identification Process for Brown s Creek to the St. Croix River and includes the work plan for conducting the TMDL study for the creek after the Stressor Identification Process has been completed. Phase II of the Brown s Creek Biological TMDL Stressor Identification Phase II 2

3 Work Tasks PHASE I: LIST CANDIDATE CAUSES As part of the Phase I Stressor Identification Process, a thorough data review and analysis of all data collected along Brown s Creek to date was completed. As a result of this analysis, the following candidate causes were identified for Brown s Creek. At this point in time, lab results have not been received for pesticides, herbicides, and metals. Therefore, these parameters are still been listed as candidate causes knowing that they may be dropped during the Phase II Stressor Identification Process. Dissolved Oxygen Temperature Sedimentation Excessive Nutrients In-stream Habitat Pesticides/Herbicides Heavy Metals Figure 1. Example of the Dissolved Oxygen conceptual model for Brown s Creek Phase II of the Brown s Creek Biological TMDL Stressor Identification Phase II 3

4 PHASE II: ANALYZE EVIDENCE This step of the Stressor Identification Process was initiated during Phase I and involved analyzing all of the historic data. This process will continue during Phase II and will include all additional data collected from all monitoring sites located from 110 th to the St. Croix River. The WCD will continue to utilize everything that is known about impaired aquatic ecosystems in this phase. All data will be organized in terms of associations that could support or refute proposed causal scenarios. Task 1: Collection of Additional Monitoring Data During Phase I of the Stressor Identification Process, all data gaps were filled through the collection of additional monitoring data and field studies from Manning Avenue to 110 th. Based on current knowledge of the Brown s Creek watershed and a cursory review of existing data, two of the three monitoring sites monitored during Phase I will continue to be monitored to capture summer and fall seasonal variation and three additional sites are being proposed (Figure 2) for additional data gathering. The following tasks will be conducted to fill in the data gaps currently known. Task 1a. Stream Classification Assessment During Phase I of the Stressor Identification Process, a geomorphic survey was conducted from Highway 96 to 110 th Street. In 1998, the Minnesota DNR completed a geomorphic assessment of the Browns Creek. Because, the relationships between habitat, flows and channel form and function is an extremely important component of stream ecology, stream classification of habitat, channel geomorphology, and sediment size will be conducted in Brown s Creek in those areas that have not been previously surveyed to gain a better understanding of the physical characteristics of the creek. The methodology proposed will follow the Rosgen Classification system outlined in the 1996 Applied River Morphology book authored by David Rosgen. If conditions allow, the proposed level of stream classification will follow the Level II assessment at a minimum. This method will be used to classify the current condition of the stream. Stream condition is described in great detail using this method resulting in a description of stream condition as it relates to stream stability, potential, and function. Key components of the assessment will be tracked using the MPCA s Index of Physical Integrity (Magner, 2006). While the Rosgen analysis can include a riparian assessment and stream habitat assessment, this analysis would be complimented by using the MPCA standard operating procedure for stream habitat assessment. Significant areas such as bank failures and debris jams will be recorded using a GPS. Field crews have been trained in Rosgen methodology through the MNDNR Fluvial Geomorphology and Stream Classification Workshops or through the Wildland Hydrology Fluvial Geomorphology and Stream Classification Workshops. Phase II of the Brown s Creek Biological TMDL Stressor Identification Phase II 4

5 Figure 2. Proposed Monitoring Sites Phase II of the Brown s Creek Biological TMDL Stressor Identification Phase II 5

6 Task 1b. Inventory Biological Community in Brown s Creek During Phase I of the Stressor Identification Process, Dr. Leonard Ferrington, Jr. from the University Of Minnesota Department Of Entomology collected Chironomidae pupal exuviae data (SFPE) once a month from April thru June and macroinvertebrate samples once upstream from 96, upstream of Manning Avenue and upstream of 110 th. During Phase II of the Stressor Identification Process, Dr. Ferrington will collect macroinvertebrate samples at five proposed locations seasonally in summer, fall and winter. In addition, Dr. Ferrington will collect SFPE at the same five locations bimonthly from July through April. The five proposed monitoring locations are: Upstream from 110 th Upstream from Manning Ave Upstream from Highway 96 Highway 5 Upstream of Highway 95 The rationale behind this rigorous sampling regime is premised on the fact that the seasonality of cold water invertebrates is very different than warm water invertebrates. In order accurately depict the biological community, sampling only during the warmest part of the year results in data that is not reflective of stenothermic taxa when in fact they may be present and found if sampling occurs at a different part of the year. Since the MPCA currently does not have a way of assessing coldwater invertebrates, Dr. Ferrington will develop species sensitivity distributions models for Brown s Creek and six other cold-water systems that are designated trout streams (Lawrence Creek, Mill Creek, Valley Creek, Eagle Creek, Trout Brook, and Pine Creek) for the MPCA. These models will be based on community structure from the perspective of species sensitivity distributions and will be used to calculate thermal and DO optima. Fisheries Data: WCD will work with either with the Minnesota Department of Natural Resources Fisheries Division, the Minnesota Pollution Control Agency or contract with a State University to perform fisheries surveys. These monitoring sites would correspond to sampling sites were flow, water quality; macroinvertebrates and habitat would also be collected. Task 1c. Groundwater Interaction A critical component of a TMDL is to identify natural versus anthropogenic sources of pollutants. In the case of Brown s Creek, understanding the relationship between the creek, groundwater, and DO is critical to reviewing the DO standard for Brown s Creek and TMDL regulations. During Phase I of the Stressor Identification process, the groundwater assessment was primarily focused on the area from Manning Avenue to 110 th. Another round of data will be collected in late summer during Phase II. Phase II of the Brown s Creek Biological TMDL Stressor Identification Phase II 6

7 Groundwater typically has lower DO concentrations than surface water because of the reducing environment through which it flows. In the Brown s Creek headwater s area, groundwater DO concentrations are hypothesized to be low because groundwater flows through decaying peat in the surrounding wetlands before discharging to the creek. Data collected from April thru June 2007 support this hypothesis. In order to ensure that this is a consistent trend, seasonal data will be collected at two of the three monitoring sites established during Phase I. In addition, three other monitoring sites will be established from Manning Avenue to the St. Croix River. Task 1d. Water Quality Monitoring Collection This task would involve continuous stream stage monitoring and water quality sampling at the proposed stream monitoring locations. Stream monitoring locations would be located and recorded using a GPS unit. Field observations, measurements and laboratory results will be recorded for data entry into the STORET database. The MPCA will provide an electronic spreadsheet in either Excel or Access format to be used to provide data to MPCA staff responsible for entering the data into the STORET database. The data will be available on the MPCA Environmental Data Access web page. Task 2: Monitoring Data Review, Analyses, and Summary The data collected in Task 1 will be reviewed, evaluated, and compared and contrasted to the conclusions drawn in Phase I. Task 3: Project Meeting One project meeting will be held with MPCA staff and a Technical Advisory Committee (TAC) after the information has been gathered for Phase II. The purpose of the meeting will be to present conclusions. The desired outcome of the meeting is an agreement by the project team that all relevant data has been collected. Phase II Work Products: Electronic files containing monitoring and field data All analytical data will be entered into STORET Data and maps in Arc View format Technical Memorandum summarizing the current biological assessment of the impaired reach of Brown s Creek Technical Memorandum summarizing the geomorphic assessment of the impaired reach of Brown s Creek Technical Memorandum summarizing the estimated groundwater inputs into Brown s Creek Meeting notes Semi-Annual Report PHASE III: CHARACTERIZE CAUSES In this step of the Stressor Identification Process, the analyzed data and other information regarding the impaired water is used as evidence to eliminate, to diagnose or to compare the strength of evidence in order to identify the probable cause of the impairment. The Phase II of the Brown s Creek Biological TMDL Stressor Identification Phase II 7

8 input information includes a description of the effects to be explained, the set of potential causes, and the evidence relevant to the characterization. Evidence is brought in and analyzed as needed until sufficient confidence in the causal characterization is reached. Task 1: Develop Strength of Evidence Tables Strength of Evidence tables will be developed that organize information so that evidence that supports or does not support each candidate cause can be easily communicated. Causal considerations that will be analyzed during this process are: Consistency of Association The repeated observation of the effect and candidate cause in different places or times. Co-occurrence The spatial co-location of the candidate cause and effect. Temporality Evaluation of whether or not the cause preceded the effect. Biological Gradient Evaluating if the effect increases with exposure. Complete Exposure Pathway The physical course a stressor takes from source to the receptors of interest. Plausibility What is the degree to which a cause and effect relationship would be expected given know facts. Analogy- Examines whether the hypothesized relationship between cause and effect is similar to any well-established cases. Task 2: Project Meeting One project meeting will be held with MPCA staff and a Technical Advisory Committee (TAC) after the strength of evidence tables have been completed. The purpose of the meeting will be to present the evidence to diagnose the primary stressor(s) impacting the biological communities within the headwaters area of Brown s Creek. The desired outcome of the meeting is a list of the primary stressor(s) agreed upon by the project team. Task 3: SI Document for Brown s Creek After receiving comments on the strength of evidence tables from MPCA staff and the TAC, a preliminary draft of the SI documentation will be drafted detailing and summarizing all steps taken throughout the process to identify the primary stressor(s) in Brown s Creek. Phase III Work Product Draft SI report (4 hard copies and 1 electronic copy) Meeting notes Semi-Annual Report Phase II of the Brown s Creek Biological TMDL Stressor Identification Phase II 8

9 PHASE IV: BROWN S CREEK TMDL Task 1: TMDL Modeling Since the stressor(s) are not yet identified within Brown s Creek, it is difficult to determine at this point, what type of modeling will be necessary. This task would begin if the stressor(s) identified are determined to be parameters for which load allocation scenarios can be developed (i.e., D.O., TSS, TP, etc.). This task would include developing a modeling strategy, setting up and calibrating a watershed model, generating allocation scenarios and margin of safety levels, assembling TMDL reports and public involvement. The WCD would develop a model using a framework such as BASINS 4.0 for this project. The WCD believes that both the MPCA and the stakeholders desire a userfriendly tool for evaluating alternative water quality management scenarios. Cost estimates are currently based on creating a SWAT (Soil and Water Assessment Tool) model of the Brown s Creek Watershed. If the primary stressor is determined to be sediment, then CONCEPTS may be a more appropriate modeling tool to use. Task 1a. Watershed Characterization and Source Assessment The TMDL modeling would be coordinated with the other major tasks such as the field monitoring and MLCCS. WCD is gathering all data relevant to the TMDL development. Specific data that would be collected as a part of this task for the Brown s Creek Watershed include the following: Regulatory listings and data supporting listings Watershed usage data Water usage goals Agricultural practices and fertilizer application rate MLCCS Data Soil Data Additional necessary field data Task 1b. Model Set Up and Calibration A model would be developed for the impaired reach of Brown s Creek. The model would be calibrated using data from 2002 through 2005 for hydrology and sediment and water quality hydrology and water quality data would be used for model validation. Model calibration and validation are necessary and critical steps in the model application. Calibration would include the comparison of both monthly and annual values, and individual storm events. In addition, when a continuous observed record is available, such as for stream flow, simulated and observed values would be analyzed on a frequency basis and their resulting cumulative distribution compared to assess the model behavior and agreement over the full range of observations. Phase II of the Brown s Creek Biological TMDL Stressor Identification Phase II 9

10 Task 1c. Generation of Allocation Scenarios and Margin of Safety In coordination with the Stakeholders, the District would develop multiple allocation scenarios for evaluation of the Brown s Creek watershed. An allocation scenario consists of an acceptable combination of the maximum allowable load from each pollution source that can be assimilated by the water body while still achieving the water quality standards. If it is determined that non-pollutant stressors are the cause of the biotic impairment, WCD would assess whether flow could be altered or stream habitat and/or channel structure could be restored to improve biotic populations. Task 2. Public Involvement Successful implementation of a TMDL project requires active community participation throughout the TMDL development. The WCD has a long record of community interaction. The WCD, working with the BCWD would stress understanding the issues and concerns of watershed citizens, stakeholders and regulatory agencies in order to define desired outcomes and develop implementation strategies. Only with this initial understanding can models developed provide the information required to determine if desired outcomes are attainable, given technical, environmental, social and financial considerations. A facilitated decision-making method or "partnership process" would be used that involves selected participants from BWCD's constituency. The foundation of the partnership process is the commitment of its participants to the process. WCD would involve constituents /partners at the beginning of the process and engage the partners throughout the process. Since the TMDL project is science-based, WCD also recommends that the Technical Advisory Committee (TAC) formed for the Stressor Identification Process is utilized for the TMDL and combined into a TAC/Stakeholder group. In addition, the Brown s Creek Watershed District has an active Citizens Advisory Committee (CAC) that would be utilized for additional feedback during the TMDL process. A total of 6 TAC/Stakeholder meetings and a total of 6 CAC meetings will be held. Key Elements for Public Involvement Meetings 1. Introduction/ TMDL primer 2. Results of Stressor Identification 3. TMDL Technical Findings 4. Develop Management Strategy 5. Incorporate Management Strategy into Pollutant Load Allocation Analysis 6. Develop Implementation Strategy Phase II of the Brown s Creek Biological TMDL Stressor Identification Phase II 10

11 Task 3. Final Report(s) Early in the project, an outline of the final TMDL report would be submitted to MPCA to ensure that the final report deliverable meets the critical documentation needs of MPCA. This outline will contain the following sections: Executive summary Problem statement Numeric targets Watershed characterization and source assessment Modeling approach and application TMDL and allocation scenarios Follow-up monitoring plan Public participation/involvement Implementation plan Phase IV Work Products: Calibrated Simulation Model and supporting documentation. Technical memorandum summarizing the evaluated and recommended allocation scenarios Draft and final TMDL reports in both hard copy and digital format. Meeting notes Semi-Annual Report Phase II of the Brown s Creek Biological TMDL Stressor Identification Phase II 11

12 Schedule Phase I of the Brown s Creek Biological TMDL Stressor Identification 12

13 Phase I of the Brown s Creek Biological TMDL Stressor Identification 14