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“Values and Features of Successful Watershed Monitoring Programs“. Thomas E. Davenport, USEPA Davenport.Thomas@epa.gov. Integrating Monitoring & Modeling. Monitoring and modeling are not mutually exclusive. Each tool has strengths and weaknesses.
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“Values and Features of Successful Watershed Monitoring Programs“ Thomas E. Davenport, USEPA Davenport.Thomas@epa.gov
Integrating Monitoring & Modeling Monitoring and modeling are not mutually exclusive. Each tool has strengths and weaknesses. Neither by itself can usually provide all of the information needed for water quality decision-making.
Use of models cannot replace monitoring, especially for project evaluation. • The most convincing evidence of watershed project effectiveness is actual measurement of conditions in the watershed and in the water body
Monitoring • Major component of water quality management • Provides essential data about the resource • Can be expensive and challenging • Requires careful design and execution to achieve objectives
Monitoring Challenges • Increased integration of fragmented environmental monitoring efforts to improve the collection, analysis, and reporting of data: • Strategic assessment of objectives • Focus on utility of resulting data 2006. Filling the gaps: Priority Data Needs and Key Management Challenges for National Reporting on Ecosystem Conditions
Role of Monitoring • Identify problems • Establish baseline conditions • Document change • Assess program/project effectiveness • Inform stakeholders • Assess compliance • Provide information/data to support models
Strengths of Monitoring • Data that document water quality improvement lend credibility to project planning and implementation • Information relevant to stakeholders • Measurement of actual watershed conditions is powerful tool for changing behavior
Monitoring Weaknesses Several major watershed monitoring projects have reported little or no improvement in water quality after extensive implementation of best management practices (BMPs) in the watershed: • Uncooperative weather • Improper selection of BMPs • Mistakes in understanding of pollution sources • Poor experimental design • Lag time
Monitoring challenges • Procedural problems can sabotage even a well-designed monitoring program • Procedural problems can be corrected with good management, training, and resources • Flawed design can doom a monitoring program from the start
ADMINISTRATIVE INDICATORS STRESSORS Agricultural Producers Implement Conservation Practices LEVEL 2: LEVEL 1: Auglaize Basin Tillage Practices 60 Ohio EPA awards 319 grants; goal is achieve restoration of impaired uses (meet WQS); Ohio DNR & NRCS develop NPS management & abate-ment strategies 50 NO TILLAGE CONSERVATION TILLAGE 40 $$$$ Percentage of Basin Acres 30 20 10 0 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 YEAR RESPONSE STRESS & EXPOSURE LEVEL 6: Biological assemblage improves BMPs Produce Reduced NPS loadings LEVELS 3-5: M&A Non Point Sources Auglaize River near Ft. Jennings, Ohio 2000 TMDL WQS 1970-74 1500 1996-98 1000 Loading (Tons/Day) Mean Daily Suspended Sediment 500 0 Annual Spring Summer Fall Winter TSS decreased, water quality & habitat improved
Monitoring challenges • Design problems • Failure to measure what is needed • Inadequate problem identification • Misunderstanding of the system being monitored • Statistically weak design
Typical monitoring program measures water quality at a relatively few points in time, then “connects the dots”. Note: Total annual load is assumed to be the area under the curve.
However: If storm events aren’t measured, the actual load may be much larger.
Many monitoring schemes miss daily variation as well. Blue dots are typical late afternoon measurements of dissolved oxygen. In many productive systems, however, DO drops to very low values at night.
All Samples Comparison of storm event data with non-storm data at 8 different urban stations in Utah Note difference in percent exceedence of pollutant criteria. All Samples Non Runoff Samples
Where to monitor? • Upstream / downstream • At bottom of watershed • Multiple sites Do you know the critical contributing areas in the watershed? Consider size of total watershed vs size of bmp
Are you monitoring in the right locations? Problem: excess sediment BMP =ebries of small in-stream sediment basins Average flow = 20 cfs
upstream downstream Upstream/downstream monitoring demonstrates impact of BMP very effectively.
But… will upstream/downstream monitoring capture all impacts?
Loading from large feeding operation swamped by the large loads carried by the Bear River. upstream downstream
Challenges for evaluation of watershed-scale BMPS Often difficult to get enough BMPs installed This makes monitoring design difficult BMPs require > 5 years to be effective at system level, which may be outside of monitoring plan scope. Limitations in monitoring strategies may miss actual changes Poor controls for other factors (changes in land use, drought, etc).
In evaluating impacts of BMPS, it is critical to look for other changes in the watershed that become the driving factors?Land use changes?Climatic patterns?Changes in ownership?
BMPs installed to protect banks from direct impacts of animal grazing. Several years later, ownership of land had changed and BMPs were no longer in place.
VT NMP Project 1993 - 2001 Evaluate effectiveness of livestock exclusion, streambank protection, and riparian restoration in reducing runoff of nutrients, sediment, and bacteria from agricultural land to surface waters
Paired watershed design • Continuous discharge • Flow-proportional automated composite sampling (weekly) • Total Phosphorus (TP) • Total Kjeldahl Nitrogen (TKN) • Total Suspended Solids (TSS) • Bi-weekly grab sampling • Indicator bacteria • Temp., conductivity, D.O. • Annual biomonitoring • Macroinvertebrates • Habitat • Fish • Annual land use/management
RESULTS Macroinvertebrate IBI improved to meet biocriteria No significant change in fish community
OR Upper Grande Ronde NMP Project 1995 - 2003 Improve salmonid community through restoration of habitat and stream temperature regime Document effectiveness of channel restoration on water temperature and salmonid community
Before/after channel restoration, with control • Continuous air & water temperature, periodic habitat assessment, snorkel surveys for fish monitoring
Results control before after • Cooler water temperatures in pools and deeper runs • Reduced width-depth ratios compared to unrestored reaches • Rainbow trout number increased in restored reaches, while constant or decreasing in unrestored and control reaches
1999 Example from grazing management project on BLM land in western Wyoming. Chicken Creek 1989 Photopoints can be are very effective at demonstrating impact.
Strengths of Modeling • Can extend the knowledge gained from monitoring • Forecast future response of alternative actions • Integrates various data and information to further test our understanding
Modeling Tools for visualizing potential results during the planning process Means to forecast the likely impacts of alternative management options Input Model Algorithms Output Factor 1 Rainfall Event System Response Land use Factor 2 Soil Pollutant Buildup Stream Pt. Source Factor 3 Others
Modeling challenges • Require reliable data on practice effectiveness. • Must address variability of BMP effectiveness. • How to model human behavior (e.g., O&M)?
Monitoring Real evidence of water quality impairment Best evidence of water quality restoration Modeling Extend and apply the knowledge Forecast future response to alternatives Integrating Monitoring & Modeling
Monitoring Fundamental knowledge about generation, fate, and transport of nonpoint source pollutants Modeling Means to assemble, express, and test current state of understanding Integrating Monitoring & Modeling
Integrating Monitoring & Modeling Evaluation of model results Improve model Guide additional monitoring
In conclusion: Keep project goals (questions) in mind when monitoring Monitor at an appropriate scale Keep time lags in mind Be selective, consider individual situations Monitor surrogates when appropriate Control or measure human behaviors / other watershed changes.