SPARROW Surface Water-Quality Modeling Web Pages
National Website:
https://water.usgs.gov/nawqa/sparrow/
Documentation of the SPARROW model for the Eastern U.S.
Hoos, A.B., Moore, R.B., Garcia, A.M., Noe, G.B., Terziotti, S.E., Johnston, C.M., and Dennis,
R.L., 2013, Simulating stream transport of nutrients in the eastern United States, 2002,
using a spatially-referenced regression model and 1:100,000-scale hydrography: U.S. Geological
Survey Scientific Investigations Report 2013-5102, 33 p.,
http://pubs.usgs.gov/sir/2013/5102/.
Documentation of the modeling tool SPARROW (SPAtially Referenced Regression On Watershed
attributes)
Schwarz, G.E., A.B. Hoos, R.B. Alexander, and R.A. Smith, 2006. The SPARROW Surface Water-Quality
Model: Theory, Application, and User Documentation. U.S. Geological Survey Techniques and
Methods Report, Book 6, Chapter B3.
https://pubs.usgs.gov/tm/2006/tm6b3/;
Preston, S.D., Alexander, R.B., Woodside, M.D., and Hamilton, P.A., 2009, SPARROW MODELING
- Enhancing Understanding of the Nation's Water Quality: U.S. Geological Survey Fact Sheet
2009-3019, 6 p.
https://pubs.usgs.gov/fs/2009/3019/
The relationship between the scale of reporting of model results and uncertainty:
Model results can be displayed at several watershed scales. The smallest scale that could
be used for reporting is the catchment scale at which model computations are made for the
Eastern United States model, these are NHDPlus catchments (1:100,000-Scale Hydrography, typical
watershed size is about 2 square kilometers or 0.8 square miles). Results can be aggregated
up to larger scales for reporting: HUC12 (typical watershed size is 90 square kilometers
or 35 square miles) or HUC8 (typical watershed size is 3,100 square kilometers or 1,200 square
miles), state, or River Basin. The SPARROW model is, in theory, scale independent. However,
the uncertainty associated with SPARROW predictions is expected to increase for drainage
basin sizes smaller than those of stream monitoring sites used to calibrate the model.
In the Oklawaha, Crystal, Lower Sante Fe, Lower Suwanee, St. Marks, and Chipola River basins
in central and northern Florida flow exchange with the underlying regional aquifer may contribute
substantial nitrogen and phosphorus influx to and outflux from the surface-water basins (Rumenik,
1988; Miller, 1990). Model predictions for these river basins are presented but may be less
reliable due to this unmodeled component of flux.
References:
Miller, JA. 1990. Ground water atlas of the United States; Alabama, Florida, Georgia, and
South Carolina. U.S. Geological Survey Hydrologic Atlas 730-G.
Rumenik, RP. 1988. Runoff to streams in Florida: Florida Geological Survey Map Series 122,
Tallahassee, Florida, Florida Geological Survey, 1 sheet.
U.S. Environmental Protection Agency and U.S. Geological Survey, 2010b, NHDPlus catchment
shapefiles Version 1: Accessed July 14, 2017, at
http://www.horizon-systems.com/NHDPlus/NHDPlusV1_home.php
U.S. Department of Agriculture-Natural Resources Conservation Service, U.S. Geological Survey,
and Environmental Protection Agency, 2016, Watershed Boundary Dataset:
http://datagateway.nrcs.usda.gov [Accessed 2/2/2016].
Incremental Load
The predicted mean annual load of the constituent (kilograms per year) leaving a stream
reach that reflects only those sources contributed from within the incremental drainage area
of that reach. The incremental load value includes the effects of in-stream attenuation processes
associated with one half of the incremental reach length. Incremental drainage areas are
represented here as “catchments”.
Accumulated Load (often referred to as "Total Load")
The predicted mean annual load of the constituent (kilograms per year) leaving a stream
reach that reflects the accumulated mass of the constituent contributed by all sources in
the total drainage area upstream of the reach outlet. The accumulated load value includes
the effects of in-stream attenuation processes in all upstream reaches.
Aggregated Load
For results grouped by 8-digit HUC, 12-digit HUC, river basin or state, aggregated
load represents the sum of incremental loads for those selected areas. Results aggregated
by State include input from catchments that cross state borders. For these catchments, the
loads were assumed to be uniformly distributed throughout the catchment. Therefore, inputs
from a given State were based on the percentage of the catchment in each state.
Incremental Yield
The Incremental Load divided by the incremental drainage area of the reach. Units are kilograms
per square kilometer per year.
Accumulated Yield
The Accumulated Load divided by the total drainage area upstream of the reach outlet. Units
are kilograms per square kilometer per year.
Aggregated Yield
The Aggregated Load divided by the sum of the “grouped by” incremental drainage areas. Units
are kilograms per square kilometer per year.
Delivered Incremental Load
Incremental load multiplied by the delivery fraction. Delivery fraction is defined below.
Delivered Accumulated Load
Accumulated load multiplied by the delivery fraction. Delivery fraction is defined below.
Delivered Aggregated Load
For results grouped by 8-digit HUC, 12-digit HUC, river basin or state, delivered
aggregated load represents the sum of delivered incremental loads for those selected areas.
Delivery fraction is defined below. Results aggregated by State include input from catchments
that cross state borders. For these catchments, the loads were assumed to be uniformly distributed
throughout the catchment. Therefore, inputs from a given State were based on the percentage
of the catchment in each state.
Delivered Incremental Yield
The Delivered Incremental Load divided by the incremental drainage area of the reach. Units
are kilograms per square kilometer per year.
Delivered Accumulated Yield
The Delivered Accumulated Load divided by the total drainage area upstream of the reach
outlet or total of the “grouped by” area. Units are kilograms per square kilometer per year.
Delivered Aggregated Yield
The Delivered Aggregated Load divided by the sum of the “grouped by” incremental drainage
areas. Units are kilograms per square kilometer per year.
Delivery Fraction (definition)
The fraction of the load leaving a reach that is not attenuated or removed by natural processes
during downstream transport to a specified downstream target reach. A delivery fraction of
1 indicates that 100 percent of the load leaving the reach is delivered to the downstream
target.
USGS Data Disclaimer:
Unless otherwise stated, all data, metadata and related materials are considered to satisfy
the quality standards relative to the purpose for which the data were collected. Although
these data and associated metadata have been reviewed for accuracy and completeness and approved
for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made
regarding the display or utility of the data for other purposes, nor on all computer systems,
nor shall the act of distribution constitute any such warranty.
USGS Software Disclaimer:
This software has been approved for release by the U.S. Geological Survey (USGS). Although
the software has been subjected to rigorous review, the USGS reserves the right to update
the software as needed pursuant to further analysis and review. No warranty, expressed or
implied, is made by the USGS or the U.S. Government as to the functionality of the software
and related material nor shall the fact of release constitute any such warranty. Furthermore,
the software is released on condition that neither the USGS nor the U.S. Government shall
be held liable for any damages resulting from its authorized or unauthorized use.
USGS Product Names Disclaimer:
Any use of trade, firm, or product names is for descriptive purposes only and does not imply
endorsement by the U.S. Government.
This web application functions best in Chrome, Firefox, or Safari. Internet Explorer works but with slower performance.
This web application has been made possible by the following open-source projects:
Lobipanel
https://github.com/arboshiki/lobipanel
Boostrap Select
https://silviomoreto.github.io/bootstrap-select
Verision v1.0.0
Link to SPARROW REST Services:
SPARROW Eastern U.S. TEST REST Services
