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NWIS Data Pulls for National- and Regional-Scale Applications
Kathy Smith (Crustal Geophysics and Geochemistry)
and Nancy Bauch (Colorado Water Science Center)
Community for Data Integration Workshop 2011
U.S. Department of the InteriorU.S. Geological Survey
Summary Statement
NWIS data are highly regarded water-quality data
There are numerous potential applications for national- and regional-scale-NWIS data, both within and outside the USGS
Use of NWIS data for national- or regional-scale GIS applications is extremely cumbersome
The current inaccessibility of the NWIS database to scientists limits its use
Our Applications
Development of Mineral Environmental Assessment Methodologies (MEA) Project Mineral Resources Program (EMEH Mission Area)
Methodologies being developed will provide information about potential environmental issues associated with known and undiscovered mineral-resource occurrences
Large regional and national scales
need to make use of existing information due to the expense involved in collecting new data
Examples of our Questions
How many surface-water water-quality records within basins less than 70 mi2 are there in the database?
How much dissolved organic carbon (DOC) data are available in the NWIS database?
How many of these records were collected from the same location?
What is the spatial distribution of these locations across the US?
Distribution of National-Scale DOC or TOC Data in the NWIS Database
from January 1985 to August 2009
map prepared by Carma San Juan
Distribution of Stream Sites in Small Basins in the NWIS Database
from January 1985 to August 2010
Site Selection
First consolidation to exclude sites:• NWIS basin size > 70 sq miles• Non-stream sites: canals, drains,
effluent, names like 13N-01E-15 BBB 1
Request to Jon Scott: Sites in NWIS with pH and basin size < 70 sq miles
Result: 23,912 sites
Site Selection
Sites with no basin size in NWIS : Estimate basin size using EDNA/CONUS
Consolidation: Exclude no basin size, check size against site name and location
End result: 12,009 stream sites with basin size < 70 sq miles
Sites grouped by state and location into 9 groups: New England, Southeast, West, etc.
Distribution of Stream Sites in Small Basins in the NWIS Database
from January 1985 to August 2010
Data Retrieval
NWIS retrieval using site id by location group and parameter list
Time period: January 1985–August 2010
3.2 million analysis results; 280,000 samples
Data Consolidation
Aggregate parameters (Result = 93 parameters)
Flag data
Quality assure data
Approximately 1,000 hours used for project
Groundwater NWIS Data Pull Attempt
Can we retrieve additional data (other than arsenic) from the same sites discussed in USGS Water-Resources Investigations Report 99-4279?
Difficulties with groundwater data retrieval
Arsenic report: One value per site, about 20,000 sites
Cumbersome to retrieve one sample per site• Thousands of sites and multiple samples per
site• Selection of time period• Record number
Regional and national data retrieval for surface water or groundwater: very cumbersome. Retrieval of data for one state: easy using WSC internal database
Use of groundwater data
Complex: Ancillary information• Aquifer, geologic material, well depth and
type, water level
Ancillary information not available for every well