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Water-Quality Monitoring: Data Collection and Analysis Strategies for Designing Program U.S. Department of the Interior U.S. Geological Survey Measuring the Success of Best Management Practices (BMP) Implementation presented by Miya N. Barr Hydrologist/Water-Quality Data Base Administrator (573) 308-3552 [email protected] Missouri Water Science Center Rolla, Missouri BMP Project Goal • The most common goal is to improve the water resources in the watershed • How can project success or failure be measured? Watershed Natural Resource Issues Involves a mix of: • Ecological, physical, and chemical variables • Social, economic, and ethical issues Evaluation Strategy Involves systematic collection of information about: • The needs the project should address • The most effective ways to meet those needs • The extent to which the project met those needs and project goals Ways to Measure Project Success Evaluation strategy should include physical and social aspects of project impacts • Water-quality monitoring to detect changes in water quality • Evaluate change in the human dimension, i.e., the application of the project and the impact of the project on people Barriers to BMP Project Evaluation • Poor planning • Failure to collect baseline data to measure change against • Selection of ineffective evaluation methods • Reliance on single evaluation method Barriers to BMP Project Evaluation, cont’d • Failure to consider both physical water-quality parameters and social/human indicators of change • Insufficient time, financial resources, and staff expertise • Overlooking the obvious, i.e., existing data Physical Indicators of Water-Quality Changes Water-Quality Monitoring: • Water chemistry • Macroinvertebrates • Algae • Fish population • Habitat measures Water-Quality Monitoring Water chemistry: • Early planning essential • Target constituents (nutrients, suspended sediment, indicator bacteria, etc.) • Importance of baseline data collection • Long-term (5-10 years) monitoring may be necessary • Monitoring can be costly • Complicated process; consult the experts U.S. Geological Survey Mission The USGS provides the Nation with reliable, impartial information to describe and understand the Earth Purpose of the USGS Water-Quality Program To provide a longterm data base so that the general water quality of the hydrologic system is known to allow for proper planning and management of potential concerns in the State Ambient Water-Quality Monitoring Network Stations: USGS/MODNR (Missouri Department of Natural Resources) Federal Program Water-Quality Stations National Stream Quality Accounting Network (NASQAN) U.S. Forest Service St. Louis: USGS/MSD (Metropolitan Sewer District) Special Studies: Water-Quality Monitoring of the East Fork of the Black River and the Black River (Taum Sauk project) Sample Collection Monthly to biannually by hydrologic technicians Typical Constituents Measured • Field parameters • Nutrients • Major ions • Trace elements • Pesticides • Indicator bacteria (Fecal coliform and E. Coli) Sampling Goals • Obtain a representative sample • Use “clean” sampling and • • processing techniques Measure unstable physical properties and chemical constituents at site Determine streamflow at time of sample collection • Quality-assurance practices What is a representative water-quality sample? A water-quality sample that represents the physical characteristics and chemical composition of the flow of a stream at the sampling point Sampling Methods of the USGS Purpose: To obtain a sample that is representative of the stream cross section • Weighted bottle • Equal-width increment • Equal-discharge increment Equal Width Increment Sampled at equal widths in cross section; verticals will have different volumes Sampling points Stream cross section Equal Discharge Increment Sampled at equal discharge increments; each vertical will have equal volume Sampling points Stream cross section Sampling Equipment “Isokinetic” and “Clean” 8-Liter Bag Sampler “Clean” Sampling Techniques “Clean” Processing Techniques Why are some physical properties and chemical constituents measured in the field? • • • Unstable and change with time Preservation is not feasible Change cannot be accurately predicted Field Measurements • Temperature • Specific conductance • pH • Dissolved oxygen • Alkalinity • Indicator bacteria Why is streamflow important? Chemical constituent concentration must be related to stream discharge • To compute constituent transport loads • To understand dischargeconstituent relations Quality Assurance Practices • Instrument calibration • Equipment blanks • Replicate samples • “Clean” techniques • National Field Quality Assurance Program After Sample Collection • Measure field parameters • Process sample for shipment to laboratory • Laboratory analysis • Retrieve data and review • Store in data base Continuous/Real-Time Water-Quality Monitoring Use YSI brand equipment Provide customers and public with web-based, real-time data (http://nwis.waterdata.usgs.gov) Continuous collection of data for up to five different parameters simultaneously Data stored in USGS database Real-time view of data Data updated hourly Continuous WQ Monitor Quality Assurance Standard guidelines set by USGS for installing and calibrating monitors, as well as reporting monitor data Monitor sites visited frequently and data watched online daily to detect issues Calibrations are checked for each parameter and documented Must correct for monitor fouling and drift in data set Continuous WQ Monitor Fouling: Before and After Ancillary Activities • Maintain a quality-assurance plan • Review quality-assurance data • Maintain data bases • Participate in National Water-Quality Assurance program • Replace and repair sampling and measuring equipment • Continuing education USGS Water-Data Collection • Experts in the field • Continuous methods development • Standardized sample collection, processing, and analysis protocols • Centralized storage of data with links to other data bases • Not biased, non-regulatory • Quality motivated, not profit motivated Conclusions • Early planning essential • Select effective evaluation methods • Consider both physical water-quality parameters and social/ human indicators of change • Allow sufficient time for monitoring; 5-10 years may be necessary to detect change Conclusions, cont’d • Collect baseline data to measure change against • Careful selection of target constituents • Be sure of financial resources; monitoring is not cheap! • Monitoring is a complicated process; consult the experts!