SPARROW modeling: Estimating nutrient, sediment, and dissolved solids transport Active
SPARROW (SPAtially Referenced Regression On Watershed attributes)
Models and interative mappers to improve understanding environmental processes
SPARROW Mappers
Modeling streamflow, nitrogen, phosphorus, and suspended sediments in streams across five regions of the United States
SPARROW (SPAtially Referenced Regression On Watershed attributes) models estimate the amount of a contaminant transported from inland watersheds to larger water bodies by linking monitoring data with information on watershed characteristics and contaminant sources. Interactive, online SPARROW mapping tools allow for easy access to explore relations between human activities, natural processes, and contaminant transport.
Featured: Projecting future flow in Southwest streams
Streamflow in the Southwestern U.S. is projected to decrease by as much as 36–80% by the end of this century, reports a new study by the U.S. Geological Survey. These decreases could challenge our ability to meet future water demand in this region.
Integration of monitoring and modeling is critical to our future understanding and management of the Nation’s water quality. Monitoring is the direct observation, often over time, of water-quality properties and characteristics, and models are tools for interpreting these observations.
SPARROW models are used to estimate long-term average values of water characteristics, such as the amount of a contaminant that is delivered downstream, based on existing monitoring data, location and strength of contaminant sources, and characteristics of the landscape.
SPARROW models can help managers:
- Determine options for reducing loads of contaminants
- Design strategies for protection or to meet regulatory requirements
- Predict changes in water quality that might result from management actions
- Identify gaps and priorities in monitoring network design
SPARROW Mappers
SPARROW mappers are interactive tools that allow the user to explore river nutrient loads and yields and the importance of different sources of contaminants in a particular river basin.
Data can be visualized using maps and interactive graphs and tables, and rankings can be shown by catchment, watershed, and state. Modeling results can be exported as an Excel spreadsheet, CSV file, or a geospatial dataset.
New mappers, representing circa 2012 source inputs, are available for 5 regions of the conterminous United States. The Mappers replace the SPARROW Decision Support System (Booth and others, 2011).
Nutrients and the Nation’s Estuaries
Access maps of watershed nutrients flowing to the Nation’s estuaries and download data tables of nutrient sources and loads. Compare nutrient sources and watersheds that contribute elevated nutrient loads to downstream receiving waters, such as the Southeast Atlantic and Gulf of Mexico, inland and coastal waters of the Northeast, the Upper Mississippi and Great Lakes, Puget Sound and the Northwest coast, and the California coast.
National Models
SPARROW models are unique in that they retain the spatial detail of underlying data sets while extending over areas as large as the conterminous United States. This allows the simultaneous assessment of water-quality conditions in many water bodies. National SPARROW models have been developed for a number of water-quality constituents including nutrients and total dissolved solids.
Regional Models
SPARROW models are flexible—they can be applied to any region where there are specific needs for water-quality information and where data to support modeling are abundant. Five new regional models of streamflow, total nitrogen, total phosphorus and suspended sediment have been developed for the conterminous United States. Other regional models have been developed previously for the Chesapeake Bay, Mississippi River and the Great Lakes watersheds.
International Models
SPARROW models can be applied in any part of the world where sufficient data are available to support model development. Examples include models developed for New Zealand to identify the primary sources of nutrients to streams (Alexander and others, 2002), and a joint U.S.-Canadian effort to build nutrient models for the entire Great Lakes watershed, to better understand nutrient loading to the lakes (Robertson and others, 2019).
Applications of SPARROW models
Once built and calibrated, SPARROW models can be applied in a variety of ways to better understand the environmental factors affecting water-quality conditions in streams.
- SPARROW models were applied at the national scale to estimate natural background levels of nutrients to help guide the potential development of nutrient criteria in streams.
- A model developed for the upper Midwest was used to identify the benefits of management practices designed to limit the amount of agricultural nutrients reaching streams (Garcia and others, 2016).
- A Chesapeake Bay SPARROW model was used to identify those areas that export nitrogen to streams with the greatest efficiency (Ator and Garcia, 2016).
- A SPARROW model was used to simulate impacts of climate change on phosphorus load to Lake Michigan (Robertson and others, 2016).
Research using SPARROW models
SPARROW models can be used as tools in research to better understand the environmental processes that affect water-quality conditions. A SPARROW model for the Mississippi drainage was used to evaluate the role of stream size on denitrification and attenuation of nitrogen levels with transport downstream. Previous studies based on a limited number of sites had hypothesized that the rate of denitrification was significantly greater in smaller streams due to greater sediment contact. This was confirmed by the SPARROW model for which the results were consistent with the other studies, but based on a much larger area and many more measurement locations (Alexander and others, 2000).
Databases
The national data bases used in the SPARROW models have value in themselves and can be used for other scientific evaluations. Attributes, such as point sources discharges, agricultural fertilizer / manure nutrients, atmospheric deposition, climate, geology / soils, land cover, hydrologic characteristics and physical characteristics, are available for all catchments in the RF1 and NHDPlus digital stream networks.
Stream network datasets and watershed attribute data
- The EPA RF1 data set (with attributes) is defined at the 1:500K scale and has stream catchments that are on average 130 km2.
- The NHDPlus data set (with attributes Version 1.1 and Version 2.1) is defined at the 1:100K scale and has stream catchments that are on average 3 km2.
Descriptions of these data sets and how they are used in SPARROW models can be found in Preston and others (2011).
What’s New …
- RSPARROW, now available on the USGS GitLab repository, provides the first open-source version of the USGS SPARROW water-quality model, with new features that improve the utility of the model for conducting studies of contaminants in surface waters and informing water resource management decisions. RSPARROW extends the capabilities of the current proprietary SAS SPARROW version and streamlines user and R developer access to SPARROW modelling technology.
- Although SPARROW models are typically based on a single time period, dynamic versions of SPARROW models are being developed to take advantage of new data sets. Dynamic SPARROW models will account for temporary storage of contaminants and to simulate seasonal variations. They also will allow simulation of contaminant loads through time to estimate the time needed for management actions on the land to affect loads in streams.
Everything you need to know about SPARROW
The links below lead to publications related to SPARROW, including documentation and applications.
Streamflow-induced variations in nitrate flux in tributaries to the Atlantic coastal zone
Data from selected U.S. Geological Survey National Stream Water-Quality Networks (WQN)
State Soil Geographic (STATSGO) Data Base for the Conterminous United States
A spatial model to aggregate point-source and nonpoint-source water-quality data for large areas
SPARROW Modeling Program
SPARROW is a popular watershed modeling technique, distributed by the USGS, that estimates the amount of a contaminant transported from inland watersheds to larger water bodies by linking monitoring data with information on watershed characteristics and contaminant sources.
- Overview
SPARROW (SPAtially Referenced Regression On Watershed attributes) models estimate the amount of a contaminant transported from inland watersheds to larger water bodies by linking monitoring data with information on watershed characteristics and contaminant sources. Interactive, online SPARROW mapping tools allow for easy access to explore relations between human activities, natural processes, and contaminant transport.
Featured: Projecting future flow in Southwest streamsStreamflow in the Southwestern U.S. is projected to decrease by as much as 36–80% by the end of this century, reports a new study by the U.S. Geological Survey. These decreases could challenge our ability to meet future water demand in this region.
Integration of monitoring and modeling is critical to our future understanding and management of the Nation’s water quality. Monitoring is the direct observation, often over time, of water-quality properties and characteristics, and models are tools for interpreting these observations.
SPARROW models are used to estimate long-term average values of water characteristics, such as the amount of a contaminant that is delivered downstream, based on existing monitoring data, location and strength of contaminant sources, and characteristics of the landscape.
SPARROW models can help managers:- Determine options for reducing loads of contaminants
- Design strategies for protection or to meet regulatory requirements
- Predict changes in water quality that might result from management actions
- Identify gaps and priorities in monitoring network design
SPARROW Mappers
SPARROW mappers are interactive tools that allow the user to explore river nutrient loads and yields and the importance of different sources of contaminants in a particular river basin.
Data can be visualized using maps and interactive graphs and tables, and rankings can be shown by catchment, watershed, and state. Modeling results can be exported as an Excel spreadsheet, CSV file, or a geospatial dataset.
New mappers, representing circa 2012 source inputs, are available for 5 regions of the conterminous United States. The Mappers replace the SPARROW Decision Support System (Booth and others, 2011).
Nutrients and the Nation’s Estuaries
Access maps of watershed nutrients flowing to the Nation’s estuaries and download data tables of nutrient sources and loads. Compare nutrient sources and watersheds that contribute elevated nutrient loads to downstream receiving waters, such as the Southeast Atlantic and Gulf of Mexico, inland and coastal waters of the Northeast, the Upper Mississippi and Great Lakes, Puget Sound and the Northwest coast, and the California coast.
National Models
SPARROW models are unique in that they retain the spatial detail of underlying data sets while extending over areas as large as the conterminous United States. This allows the simultaneous assessment of water-quality conditions in many water bodies. National SPARROW models have been developed for a number of water-quality constituents including nutrients and total dissolved solids.
Regional Models
SPARROW models are flexible—they can be applied to any region where there are specific needs for water-quality information and where data to support modeling are abundant. Five new regional models of streamflow, total nitrogen, total phosphorus and suspended sediment have been developed for the conterminous United States. Other regional models have been developed previously for the Chesapeake Bay, Mississippi River and the Great Lakes watersheds.
International Models
SPARROW models can be applied in any part of the world where sufficient data are available to support model development. Examples include models developed for New Zealand to identify the primary sources of nutrients to streams (Alexander and others, 2002), and a joint U.S.-Canadian effort to build nutrient models for the entire Great Lakes watershed, to better understand nutrient loading to the lakes (Robertson and others, 2019).
Applications of SPARROW models
Once built and calibrated, SPARROW models can be applied in a variety of ways to better understand the environmental factors affecting water-quality conditions in streams.
- SPARROW models were applied at the national scale to estimate natural background levels of nutrients to help guide the potential development of nutrient criteria in streams.
- A model developed for the upper Midwest was used to identify the benefits of management practices designed to limit the amount of agricultural nutrients reaching streams (Garcia and others, 2016).
- A Chesapeake Bay SPARROW model was used to identify those areas that export nitrogen to streams with the greatest efficiency (Ator and Garcia, 2016).
- A SPARROW model was used to simulate impacts of climate change on phosphorus load to Lake Michigan (Robertson and others, 2016).
Research using SPARROW models
SPARROW models can be used as tools in research to better understand the environmental processes that affect water-quality conditions. A SPARROW model for the Mississippi drainage was used to evaluate the role of stream size on denitrification and attenuation of nitrogen levels with transport downstream. Previous studies based on a limited number of sites had hypothesized that the rate of denitrification was significantly greater in smaller streams due to greater sediment contact. This was confirmed by the SPARROW model for which the results were consistent with the other studies, but based on a much larger area and many more measurement locations (Alexander and others, 2000).
Databases
The national data bases used in the SPARROW models have value in themselves and can be used for other scientific evaluations. Attributes, such as point sources discharges, agricultural fertilizer / manure nutrients, atmospheric deposition, climate, geology / soils, land cover, hydrologic characteristics and physical characteristics, are available for all catchments in the RF1 and NHDPlus digital stream networks.
Stream network datasets and watershed attribute data
- The EPA RF1 data set (with attributes) is defined at the 1:500K scale and has stream catchments that are on average 130 km2.
- The NHDPlus data set (with attributes Version 1.1 and Version 2.1) is defined at the 1:100K scale and has stream catchments that are on average 3 km2.
Descriptions of these data sets and how they are used in SPARROW models can be found in Preston and others (2011).
What’s New …
- RSPARROW, now available on the USGS GitLab repository, provides the first open-source version of the USGS SPARROW water-quality model, with new features that improve the utility of the model for conducting studies of contaminants in surface waters and informing water resource management decisions. RSPARROW extends the capabilities of the current proprietary SAS SPARROW version and streamlines user and R developer access to SPARROW modelling technology.
- Although SPARROW models are typically based on a single time period, dynamic versions of SPARROW models are being developed to take advantage of new data sets. Dynamic SPARROW models will account for temporary storage of contaminants and to simulate seasonal variations. They also will allow simulation of contaminant loads through time to estimate the time needed for management actions on the land to affect loads in streams.
- Science
Everything you need to know about SPARROW
What is SPARROW? SPARROW (SPAtially Referenced Regression On Watershed attributes) is a watershed modeling technique for relating water-quality measurements made at a network of monitoring stations to attributes of the watersheds such as contaminant sources and environmental factors that affect rates of delivery to streams and in-stream processing. The core of the model consists of a nonlinear... - Data
- Multimedia
- Publications
The links below lead to publications related to SPARROW, including documentation and applications.
Filter Total Items: 64Streamflow-induced variations in nitrate flux in tributaries to the Atlantic coastal zone
Streamflow-related variability in nutrient flux represents an important source of uncertainty in managing nutrient inputs to coastal ecosystems. Quantification of flux variability is of particular interest to coastal resource managers in adopting effective nutrient-reduction goals and monitoring progress towards these goals. We used historical records of streamflow and water-quality measurements fAuthorsR. B. Alexander, Peter S. Murdoch, R. A. SmithData from selected U.S. Geological Survey National Stream Water-Quality Networks (WQN)
This CD-ROM set contains data from two USGS national stream water-quality networks, the Hydrologic Benchmark Network (HBN) and the National Stream Quality Accounting Network (NASQAN), operated during the past 30 years. These networks were established to provide national and regional descriptions of stream water-quality conditions and trends, based on uniform monitoring of selected watersheds throuAuthorsRichard B. Alexander, J. R. Slack, A. S. Ludtke, K. K. Fitzgerald, T. L. Schertz, L. I. Briel, K. P. ButtlemanState Soil Geographic (STATSGO) Data Base for the Conterminous United States
USSOILS is an Arc 7.0 coverage containing hydrology-relevant information for 10,498 map units covering the entire conterminous United States. The coverage was compiled from individual State coverages contained in the October 1994 State Soil Geographic (STATSGO) Data Base produced on CD-ROM. The geo-dataset USSOILS.PAT relates (on the basis of a map unit identifier) the 10,498 map units to 78AuthorsGregory E. Schwarz, R. B. AlexanderA spatial model to aggregate point-source and nonpoint-source water-quality data for large areas
More objective and consistent methods are needed to assess water quality for large areas. A spatial model, one that capitalizes on the topologic relationships among spatial entities, to aggregate pollution sources from upstream drainage areas is described that can be implemented on land surfaces having heterogeneous water-pollution effects. An infrastructure of stream networks and drainage basins,AuthorsD.A. White, R. A. Smith, C. V. Price, R. B. Alexander, K. W. Robinson - Web Tools
- Software
SPARROW Modeling Program
SPARROW is a popular watershed modeling technique, distributed by the USGS, that estimates the amount of a contaminant transported from inland watersheds to larger water bodies by linking monitoring data with information on watershed characteristics and contaminant sources.
- News