SPARROW models are used to estimate long-term average values of water characteristics, such as the amount of a contaminant that is delivered downstream, on the basis of existing monitoring data, location and strength of contaminant sources, and characteristics of the landscape.
Modeling results can help managers determine how to reduce loads of contaminants and design protection strategies; design strategies to meet regulatory requirements; predict changes in water quality that might result from management actions; and identify gaps and priorities in monitoring.
SPARROW (SPAtially Referenced Regressions On Watershed attributes) is a watershed modelling technique developed by the USGS in the late 90s. Its primary use is to 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. SPARROW models explore relations between human activities, natural processes, and contaminant transport using interactive Mappers.
SPARROW models are used to estimate long-term average values of water characteristics, such as the amount of a contaminant that is delivered downstream, on the basis of existing monitoring data, location and strength of contaminant sources, and characteristics of the landscape. The model was initially developed to;
Statistical methods are used in SPARROW modelling to explain in-stream measurements of water quality (constituent mass or load) in relation to upstream sources and watershed properties (soil characteristics, precipitation amounts, and land cover) that influence the transport of constituents to streams and their delivery to receiving water bodies, including estuaries.
The sparrow model once set up for a given catchment or study area can be useful in enhancing a monitoring plan by identifying additional sampling sites which adds to optimizing monitoring, reducing statistical uncertainty and better meeting modelling objectives.
Modelling results can help managers better understand spatial variations in pollution sources and the environmental and hydrologic processes that control their transport and dispersal. The direct result of this is that managers are better informed to determine how to reduce loads of contaminants and design protection strategies; design strategies to meet regulatory requirements; predict changes in water quality that might result from management actions; and identify gaps and priorities in monitoring.
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 modelling are abundant. SPARROW models can be applied in any part of the world where sufficient data are available to support model development. A model was developed for New Zealand to identify the primary sources of nutrients to streams (Alexander et al., 2002)
|State of Development||Stable Release|
|Current Development Activity||Still active development. Mostly going into US national and regional applications.|
|Intended End Users||Direct users are specialist catchment modellers, but intended broader use is for water management.|
|Temporal Resolutions||Not applicable|
|Temporal Extents||Not applicable|
|Steady State or Dynamic||Steady State|
|Operating Systems||MS Windows, Linux|
|User Interface||Please Select|
|Ease of Use||Moderate|
Documentation and Software download page
|Support||No formal support, although the authors are willing to assist.|
|Users Forum||Not available.|
|Programming Language||SAS (statistical software system) macro language, including IML language within SAS. Also uses some dll's originating in Fortran.|
|Methods included for calibration and validation||Constrained non-linear least squares|
|Linkages to other Models|
The prediction component of NZ Sparrow applications have been re-coded in VB and Fortran and incorporated into CLUES.
Sparrow home page - http://water.usgs.gov/nawqa/sparrow/
The SPARROW Surface Water-Quality Model: Theory, Application and User Documentation. U.S. Geological Survey Techniques and Methods, Book 6, Section B, Chapter 3
SPARROW MODELING—Enhancing Understanding of the Nation’s Water Quality: https://pubs.usgs.gov/fs/2009/3019/pdf/fs_2009_3019.pdf
Nutrients in Waikato Catchment (Waikato): Alexander, R. B., Elliott, A. H., Shankar, U., & McBride, G. B. (2002). Estimating the sources and transport of nutrients in the Waikato River Basin, New Zealand. Water resources research, 38(12).
Estimation of nutrient sources and transport for New Zealand (NZ): Elliott, A. H., Alexander, R. B., Schwarz, G. E., Shankar, U., Sukias, J. P. S., & McBride, G. B. (2005). Estimation of nutrient sources and transport for New Zealand using the hybrid mechanistic-statistical model SPARROW. Journal of Hydrology (New Zealand), 1-27.