New England SPARROW Data Viewer
TOTAL NITROGEN MODEL RESULTS
The New England SPARROW model for total nitrogen has an R-squared value of 0.95, with mean square error of 0.16. Variables that are statistically significant in the total-nitrogen model include permitted municipal wastewater discharges, atmospheric deposition, agricultural area, and developed (urban and suburban) land area. Total-nitrogen in-stream-loss rates are significant only in streams with average annual flows less than or equal to 2.83 cubic meters per second (100 cubic feet per second) with a half-life of about 0.9 days. For streams larger than this, the model did not detect statistically significant annual in-stream loss of total nitrogen in New England.
The model form is found on page 3, equation 1, of the report. The total nitrogen model coefficients are listed on page 14, table 3, of the report. (USGS SIR2004-5012)