SSN2
SSN2: Specialized R modeling for stream-network data, with prediction and diagnostics. Ranked #60 of 64 in GIS Software by our editors (3.2/10); pricing: Free plan; best for researchers modeling spatial stream networks in R.
At a glance
- Editor score3.2 / 10
- PricingFree plan
- Best forResearchers modeling spatial stream networks in R
- Free planYes
- Paid fromFree
- Spatial analysisAdvanced
- Facts checked24 Sep 2026

Where it wins
- Fits linear and generalized linear models for stream networks
- Predicts values at unobserved locations and calculates hydrologic distances
- Includes cross-validation, simulation, and model diagnostics
Where it doesn't
- Focused on stream-network statistics, not general-purpose GIS
- Requires working with R and local data processing
- Desktop deployment limits the listed platform coverage
Our verdict on SSN2
SSN2 is an open-source R package for researchers and analysts working with spatial stream-network data. It fits linear and generalized linear models that account for network structure, water-flow direction, stream distances, and Euclidean spatial dependence. The package is aimed at statistical analysis of streams rather than broad GIS tasks, making it a fit for people whose work centers on modeling connected waterways and their spatial relationships.
Its modeling workflow includes prediction at unobserved stream locations, calculation of hydrologic distance matrices, and support for tail-up, tail-down, and Euclidean spatial dependence. Users can also perform leave-one-out cross-validation, simulate spatially autocorrelated variables on stream networks, and inspect fitted-model diagnostics and empirical semivariograms. These capabilities give the package a focused set of tools for fitting, checking, and interpreting stream-network models; the same specialization means it is not a substitute for a general-purpose GIS application.
SSN2 is open source and has a free plan. Its official documentation describes installation in R and local data processing, so it suits analysts comfortable working in that environment. Email and community support channels are listed. The package is described as a desktop deployment, with no integrations or broader platform coverage specified. Researchers seeking stream-network statistical modeling at no cost should consider it; teams looking for a wider GIS feature set or platform ecosystem should look elsewhere.
Your product? Our editors can test SSN2 in depth and publish a review, labelled as paid · from $149/mo →
SSN2 pricing
SSN2 fact sheet
| Free plan | Yes |
|---|---|
| Paid from | Free |
| Deployment | Desktop |
| Spatial analysis | Advanced |
| Web mapping | Not verified |
| Dashboard builder | Not verified |
| Raster data support | Not verified |
| Mobile apps | Not verified |
| Deployment | Desktop |
| Support | Email, Community |
| Built for | Small business, Mid-market, Enterprise (editorial estimate) |
| Pricing | Free plan |
| Website | usepa.github.io |
| Facts checked | 24 Sep 2026 |
Alternatives to SSN2
- QGISA broad, no-cost GIS for advanced analysis, editing, mapping, and publishing.9.4
- GRASS GISA deep analytical GIS for technical teams that value open-source and scripted workflows.9.2
- Google Earth EngineA specialized GIS platform for large-scale satellite imagery, raster analysis, and geospatial computation.9.1
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Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
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