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EXPECTED CONDITION

EXPECTED CONDITION. Introduction to Some Basic Concepts for the Development of Colorado’s Conceptual Model. PROJECT OBJECTIVES. Develop a ‘top down’ reference stream/reach screening approach Develop a process to identify ‘least disturbed’ reference sites in any bio-physical stratum

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EXPECTED CONDITION

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  1. EXPECTED CONDITION Introduction to Some Basic Concepts for the Development of Colorado’s Conceptual Model

  2. PROJECT OBJECTIVES • Develop a ‘top down’ reference stream/reach screening approach • Develop a process to identify ‘least disturbed’ reference sites in any bio-physical stratum • Key: practical, based on readily available data, reproducible, regionally flexible • Develop a Protocol or Guidance document that will reflect Colorado’s approach to Biological Assessments

  3. “The true health of our aquatic environments is reflected by the biological communities that reside within them” Prof. J. Karr University of Washington

  4. WHAT ARE REFERENCE CONDITIONS?(from EPA) • Reference conditions represent the best biological conditions that can be found in a body of water that has not been impacted by humans.

  5. REFERENCE CONDITIONCAN BE: • Minimally Disturbed Condition • Least Disturbed Condition • Best Attainable Condition

  6. MINIMALLY DISTURBED CONDITION • Condition in the absence of significant, or minimal human disturbance (e.g., “natural”, “pristine”, or “undisturbed”) • An absolute. Some regions might have no sites that meet minimal disturbance criteria. • MDC changes little over time, due to natural processes • Stable benchmark • Derived from minimally disturbed reference sites

  7. LEAST DISTURBED CONDITION • Best available given today’s state of the landscape • Found in conjunction with the best available physical, chemical, and biological habitat given today’s state of the landscape • Relative. No matter how disturbed the region, some sites are likely less disturbed than others. • Can change over time as land use and management practices change • Derived by characterizing least disturbed reference sites

  8. BEST ATTAINABLE CONDITION • Best Attainable Condition - this condition is equivalent to the ecological condition of (hypothetical) least disturbed sites where the best possible management practices are in use

  9. COLORADO’S PROPOSED DEFINITION • Expected Condition – the physical, chemical and biological conditions found at reference sites should represent the best attainable conditions that can be achieved by similar streams within a particular geographic region, given today’s state of the landscape

  10. THERE ARE TWO APPROACHES TO ESTIMATE THE REFERENCE (EXPECTED) CONDITION: • Classification predicts the expected biotic condition of a waterbody from previously observed associations between biotic attributes and categorical descriptors of a waterbody’s environmental setting. • Modeling predicts the expected biotic condition by mathematically describing how biota vary along environmental gradients.

  11. IMPROPER CLASSIFICATION LEADS TO BAD DECISIONS: Scientist, Manager, or Regulator Stakeholder

  12. THE EXPECTED CONDITION OF A SITE WILL ALWAYS BE SOMEWHAT “FUZZY” BECAUSE: • Un-impaired sites are not static - they are in dynamic equilibria. • There is measurement error associated with estimating the value of an indicator. • There is variance associated with the effects of un-measured, naturally occurring factors.

  13. Reference Site Selection

  14. THE WORLD IS NATURALLY HETEROGENEOUS AND “EXPECTED” MAY NOT BE OBVIOUS We need to establish the correct match between an assessed site and its expected condition, so we need …

  15. GOOD REFERENCE SITES THAT • Mimic natural gradients of the region of interest, and …. • are representative of the stream and habitat of interest

  16. REFERENCE SITE SELECTION IS: • An iterative screening process for selecting sites • That are minimally or least disturbed by human activities and resultant stressors • That are representative of the aquatic resource in the region of interest

  17. THE PROBLEM OF REPRESENTATIVENESS • This problem really boils down to whether the range of environmental and biological conditions in the population of reference sites is equivalent to the range that would occur in the population of all other sites of interest. • Reference site ‘quality’ will almost always vary across classes of sites, so we must be careful about what we mean by “reference”.

  18. ACCOUNTING FOR NATURAL VARIABILITY – HOW MUCH IS ENOUGH? • How much we need to account for is a function of how small of a response we want/need to detect, which needs to be decided by stakeholders up front!!!

  19. THE ROLE OF REFERENCE SITES IN CLASSIFICATION AND MODELING: • The use of reference sites is an empirical approach to estimating Reference Condition. • Accurate and precise predictions from reference site data depend on: • Agreed upon and acceptable criteria for defining reference site quality, • Acceptable means of extrapolating/interpolating.

  20. Human Activities (Disturbance) Stressors (Habitat Responses) Biological Responses A SIMPLE CONCEPTUAL MODEL:The key is to identify common patterns of biological responses to human disturbances

  21. A more complex conceptual model (from Bryce et al. 1999. J. Am. Wat. Resour. Assoc. 35:23-36) Human Activity Urbanization Channelization Levees Roads/Culverts Erosion MWTPs/CSOs Septic systems Imperviousness Fragmentation Ag/CAFO/ Silviculture Grazing Harvest Dams Channelization Diversions Levees Roads/Culverts Erosion Fertilizer Pesticides Compaction Fragmentation Mining/ Drilling Extraction Metals Liming Tailings Valley Fill Diversions Roads/Culverts Erosion Petroleum Pipelines Fragmentation Compaction Industry/ Power Gen. Dams Stacks Liming Wastewater WTP/CSOs Roads/Culverts Channelization Revetments Imperviousness Fragmentation Stressors (Habitat change) Habitat Flow Sediment Nutrient Oxygen Temperature Toxics Biological Responses Altered Biological Structure/Function

  22. EXTENSIVE DATA • Identify sources of complete coverages • GIS resources? • Geo-Referenced databases? • Sources of data • At the landscape screening level • Land use/cover (TM imagery; other satellite imagery) • Roads • Population density/points sources • Mines • Feedlots • …

  23. OFFICE DATA • Identify sources of candidate sites • Air photos, digital orthophoto quads, maps • Sources of data • Terraserver • USGS topo maps/local maps • National High Altitude Photography (NHAP) • Satellite imagery

  24. SITE RECONNAISSANCE • By air • By ground site visit • ID disturbances missed by the coarser filters • Local knowledge/local land managers • Input from Best Professional Judgement

  25. SITE MEASUREMENTS • Apply routine field protocol • EMAP • USGS • STATE • RIVPACS • To identify disturbances missed by coarser screens: • Riparian habitat • Physical habitat • Water quality • Biota

  26. SOME EXAMPLES OF CRITERIA TO SELECT REFERENCE SITES

  27. CRITERIA SET # 1 • Drainage: entirely within subregion • Land use: >80% forest; no ag/urban; no recent disturbance, e.g., construction; clearcutting • Habitat: No cattle in w/s; no disturbances • Channel: Characteristic of region • Riparian veg: > 30m buffer for most of w/s • Instream substrate: no significant siltation or embeddedness • Water Quality: No point sources; no recent spills; pH>6.

  28. CRITERIA SET # 2 “Filters”: exclude all sites with: • sulfate over 400 ueq/L (mine drainage) • acid neutralizing capacity less than 50 ueq/L (acid rain) • average RBP habitat score less than 16 (habitat) • total phosphorus over 100 ug/L (nutrient enrichment) • total nitrogen over 750 ug/L (nutrient enrichment) • chloride over 100 ueq/L (general watershed disturbance • total benthic count less than 100 individuals (inadequate sample)

  29. Criteria for Alaska Reference Sites (Must meet all criteria) • no channelization • no upstream impoundments • no known point source dischargers • dissolved oxygen greater or equal to 5 ppm • urban land use less than 15% in catchment • mining and/or logging affecting less than 15% in catchment • forest land use (or other natural wetland, grassland) greater than 70% in catchment • riparian buffer width greater or equal to 18 m

  30. EXAMPLE OF CRITERIA FROM MISSOURI • Wastewater treatment plants and other point sources • Confined animal feeding operations • Instream habitat • Riparian habitat • Land use and land cover, broad scale • Land use and land cover, site specific • Physical and chemical water parameters • Biological metrics • Faunal assemblages • Altered hydrologic regime • Representativeness

  31. INITIAL DEVEOPMENT PHASE 0-18 MONTHS INITIAL IMPLEMENTATION PHASE 12-24 MONTHS INITIAL ASSESSMENT PHASE FULL ASSESSMENT PHASE 18 MO – 6 YEARS 5 – 10 YEARS Start-Up Tasks: Logistics Start-Up Tasks: Implementation Program Implementation Program Maintenance Acquire Staffing: Initiate Field Sampling: Biocriteria Development: Biocriteria Development: • Professional biologists with expertise & training • Database manager • Interns/technicians (field work, lab tasks • Review spatial designs • Develop QA/QC and QAPP • Develop sampling plans in accordance with monitoring strategy • Pilot assessments • Select candidate metrics and/or assessment tools • Develop refined uses - narratives • Test metrics and develop calibrated indices • Evaluate via bioassessments • Refine metrics and develop calibrated indices • Develop reference benchmarks for calibrated indices according to classification scheme and by major aquatic ecotype Acquire Facilities & Equipment: • Outfit laboratory and field facility • Office accommodations • Database support infrastructure Classification Issues: Water quality Program Support: • Consider spatial stratification issues • Develop and test reference condition approach • Select and sample reference sites • Develop index development and calibration strategy Water quality Program Support: • Fully functioning bioassessment program supports WQS (UAAs, aquatic life use support) and basic program needs (305b/303d) • Program development should be fully initiated – e.g., integrated chemical, physical, and biological database supports criteria & policy development • Develop capacity to support WQ programs (WQS/UAAs, TMDLs, permits, planning) • Formalize water quality program support as capacity is developed Methods Development: • Review and select candidate methods and protocols • Consider MQO/DQO needs • Test methods for applicability • Analyze test results – select methods Continuously evaluate program Evaluate effectiveness of initial decisions – make needed adjustments Quality Improvement Process Bioassessment and Biocriteria Program Development Timeline

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