Tracing Demo 3: Upstream Facilities
Demo Question: What facilities are upstream of water samples with PFOA concentrations above 4 ppt in Cumberland County, Maine?
Use Case Area: Trace Contamination Pathways
This demo shows how SAWGraph can begin with elevated PFAS sample results and trace upstream through the surface water network to identify facilities and industry sectors associated with upstream areas. It demonstrates how hydrologic relationships can support investigation of possible source-to-result relationships.
What This Demo Connects
PFAS Samples
Surface water sample locations in Cumberland County that meet the selected PFOA concentration threshold.
Upstream Hydrology
Waterbodies and upstream flowlines used to trace hydrologic pathways from selected sample locations.
Facilities and Industries
Facilities associated with upstream areas, grouped by represented manufacturing industry classifications.
Demo Results
The map shows qualifying surface water samples, waterbodies, upstream flowlines, and facilities returned from the SAWGraph queries for Cumberland County, Maine. Results reflect the datasets represented in the graph, the selected substance and sample type, the geographic area, the concentration threshold, and the conditions of the queries.
The mapped facilities are grouped by industry classification so that users can compare possible upstream relationships across different facility types. An upstream hydrologic relationship can identify locations that may warrant further investigation, but it does not establish that a facility released PFAS or caused a particular sample result.
The map is interactive. Pan and zoom to explore the results, use the layer control to show or hide different types of features, and explore mapped features for additional information.
Upstream Samples, Flowlines, and Facilities
This example begins with surface water samples above the selected PFOA threshold and traces upstream through connected waterbodies and flowlines. Facilities associated with those upstream areas are then displayed by industry classification.
Available layers include counties, samples, waterbodies, upstream flowlines, and multiple manufacturing industry categories represented among the upstream facilities.
Code and Query Resources
The full query workflow supports selection of the PFAS substance, sample material type, administrative region, and minimum concentration.
The query notebook for this demo is not currently available online.