Nutrient Fluxes in the New River, NC:

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Nutrient Fluxes in the New River, NC
The Dark Side of Hog Farms
Rae Mooney Hydrology May 1, 2007
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New River Watershed

• 1,436 km2
• Fisheries
• Economy
• Recreation
• Home to 138 CAFOs
• July 1995 Holding pond ruptures on New River
• 25 million tons of hog waste

Mallin et al., 2005
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Map of Study Area
M52
172
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Percentages of LULC
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Effects of Hog Farms and other Agriculture

• Increased Eutrophication
• Waste ponds overflow
• Spray waste on fields overapplication
• Now, LESS farms w/ MORE HOGS
• TOXIC and harmful to humans
• Discharge more than waste
• Harmful Algal Blooms
• Secrete toxins
• Seafood toxic to eat

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(No Transcript)
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LOADEST Load Estimator

• Estimates constituent loads using Linear
  Regression
• Input daily streamflow, data variables, monthly
  constituent concentrations
• Output daily constituent concentrations,
  residuals, z-scores, regression statistics from
  models

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Input Files
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Output Files
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Stats and Models
Site-Constituent Model-based on AIC PPCC
NH4-M52 2 0.9901
NH4-172 9 0.9971
NO3-M52 7 0.9907
NO3-172 9 0.9473
PO3-M52 9 0.9919
PO3-172 7 0.9919
Normal Distribution MLE Max Likelihood
Estimation AMLE Adjusted MLE (less biased) PPCC
not normal distribution LAD Least Absolute
Deviation
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Hurricane Floyd (500 yr Storm) September
9-17th, 1999
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Hurricane Floyd
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Conclusions

• Must be careful to use BEST model
• User-friendly
• sometimes
• Overall useful tool since continuous sampling
  impossible

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Tomorrow

• For comparison
• Chat w/ scientist at N.C. Division of Water
  Quality
• Sampling from Hurricane Floyd
• Look at effects of new wastewater treatment
  plants in 1998

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Questions??