Massachusetts SWAT+ modeling | SWATGenX

Narragansett — USGS 01109090: documented SWAT+ USGS station watershed snapshot with Explorer-aligned maps.

SWATGenX documents a sample SWAT+ watershed model in Massachusetts for Narragansett (USGS 01109090). The overview covers 89.7 km² with 4578 HRUs and 291 channels, with cranberries prominent in the exported land-cover summary, using the same CONUS national data stack as every production build. Review DEM, land-cover, and structure summaries on this page, then open Watershed Explorer to model your own gage or HUC, or browse downloadable packages in the example models catalog.

Part of SWAT+ modeling by stateon SWATGenX: a sample example model for this state, built with the same CONUS national datasets as Watershed Explorer. Browse downloadable example models.

Why watershed modeling matters

Watershed models help connect landscape processes, managed systems, and channel routing to questions about water supply, water quality, and flood timing. SWAT+ represents those linkages over multi-year climate forcing using national soils, land cover, and hydrography. Study-specific calibration, local observations, and endpoint models remain the responsibility of each project team.

Case study basin: Narragansett

DEM terrain shading
Narragansett · Massachusetts — DEM hillshade, basin mask (same layout as flood-report maps)
USDA CDL land use
Narragansett · Massachusetts — Cropland Data Layer land use, basin clip

Below is a documented SWAT+ model-build snapshot for the Narragansett watershed—the same export class as Watershed Explorer. The metric strip, maps, charts, NHD flowline-length summary by feature class, and fact tables follow from that committed export.

89.7 km²
Watershed area
4578
HRUs
291
Channels
4
Lakes / reservoirs (GIS)
101.7 km
NHD-linked stream length
19
PRISM stations

The metric strip, fact tables, and optional DEM/CDL maps describe the exported SWAT+ workspace for Narragansett (HUC8 01090004). NHD-linked stream statistics and PRISM climate headers follow the same conventions as other SWATGenX state sample models across CONUS.

Counties in the basin overlay: Bristol, Plymouth.

  • Runoff timing and climate variability across multi-year forcing
  • Channel routing and NHDPlus HR hydrography linkage
  • Land cover and HRU discretization for management screening
  • Reproducible SWAT+ package delivery via SWATGenX

Basin distributions (Narragansett · Massachusetts)

CDL charts use the same basin-clipped raster summary as Explorer watershed reports. County population bars use US Census county-or-equivalent polygons only (not state, city, or township layers): one published headcount per county that intersects the basin, then summed for screening—not watershed-apportioned density.

CDL land cover (basin clip)
CDL cropland & permanent crops (share)

Population by county (overlay)

Land-cover mix (km², CDL clip)

Climate forcing (Narragansett · Massachusetts)

Monthly climatology from basin PRISM precipitation and temperature plus NSRDB humidity, solar radiation, and wind files. The line is the mean daily value for each calendar month (averaged across all station files and years); the shaded band is the P05–P95 spread of those daily values (2000-01-01 – 2024-12-31). Source grid: 20 PRISM/NSRDB grid cells (4 km).

Precipitation
mm day⁻¹ (PRISM)
Relative humidity
% (NSRDB)
Wind speed*
m s⁻¹ (NSRDB MERRA-2, ~2 m)
Daily maximum temperature
°C max (PRISM)
Daily minimum temperature
°C min (PRISM)

* Wind speed. MERRA-2 at ~2 m above ground (not 10 m hub height). Daily arithmetic mean of 48 thirty-minute NSRDB steps; curves are monthly basin means with P5–P95 spread. NREL documents this for solar forcing, not wind-resource assessment.

Key facts

The first table lists basin id, climate window, CDL and population context, and the two published stream-length definitions (channel routing versus NHD-linked stream GIS). The strip above still carries headline structure counts (HRUs, channels, lakes).

MetricValue
WBD HU8 nameNarragansett
USGS site (HUC12 model folder)01109090
WBD region (VPUID)0109
Watershed area89.74 km²
SWAT+ stream GIS segments (NHDPlusID → NHDFlowline)321
Stream length — channel routing (rivs1, projected)92.81 km
NHD-linked stream length, GIS projected101.73 km
DEM resolution (m)29.88
CDL cropland (basin clip)0.62 km²
CDL wetland (Woody + Herbaceous)20.56 km²
CDL developed18.81 km²
Population (by county, Explorer overlay)1,110,019
Counties (gov. units)2
Climate period (PRISM header)2000-01-01 – 2024-12-31
Stats exported (UTC)2026-05-21 17:08 UTC
SWATGenX snapshot ID0109/huc12/01109090
Snapshot labelNarragansett (Massachusetts) — usgs_station — exported workspace
Model statistics generated (UTC)2026-05-21T17:08:40Z

How to read this table: each row starts from Watershed/Shapes/SWAT_plus_streams.shp, where each segment carries NHDPlusID. Those IDs join to NHDFlowline in the USGS NHDPlus HR HU4 geodatabase (VPUID 0109). Lengths add in EPSG:5070 (planimetric km) and roll up by NHD FType / FCode. Row lengths sum to 101.73 km over 321 segments.

NHD class (label)Length (km)ShareSegments
Stream / river (perennial / general)FType 460 · FCode 4600654.8453.9%142
Artificial path (NHD)FType 558 · FCode 5580030.830.3%126
Stream / river (intermittent)FType 460 · FCode 4600313.4713.2%39
ConnectorFType 334 · FCode 334002.542.5%12
Canal / ditchFType 336 · FCode 336000.090.1%2

The county total matches the bar chart: county-or-equivalent units only (cities and townships excluded), one Census headcount per county intersecting the basin. Screening context only—not basin density or a regulatory design population.

SWATGenX documented snapshot (usgs_station) for Massachusetts: model id 0109/huc12/01109090. Values come from the exported SWAT+ workspace plus Explorer-style overlays where present; they support screening and documentation, not regulatory determinations.

What SWATGenX generates

SWATGenX assembles national inputs, runs the QSWAT+ / SWAT+ Editor workflow, and exports a reviewable SWAT+ workspace (TxtInOut + GIS + SQLite). Open the package in SWAT+ Editor for scenarios; add calibration and validation with local data where your study requires it.

Related on SWATGenX

National datasets (labels)

NHDPlus-HR
PRISM
NLCD
gSSURGO
DEM
USGS NWIS

This sample build uses the same CONUS resolutions as every SWATGenX package—NHDPlus HR at 1:24k, 30 m terrain (from 10 m 3DEP), 250 m NLCD/CDL (from 30 m), 250 m gSSURGO (from 10 m), ~4 km PRISM, and daily NSRDB at PRISM stations (from ~2 km, 30-minute data). See SWAT+ by state for the full stack. Methodology & provenance.

Citations for on-page facts

  • Hydrologic catalog: USGS WBD — USGS station 01109090 (HUC12-located SWAT+ model)
  • Hydrography: USGS NHDPlus HR — SWAT+ ``SWAT_plus_streams.shp`` ``NHDPlusID`` joined to HU4 ``NHDFlowline`` (FType/FCode); lengths summed in EPSG:5070 for the distribution table.
  • Land cover (CDL): USDA NASS Cropland Data Layer (clipped to basin)
  • Climate forcing: PRISM Climate Group (OSU), daily met files referenced in weather-sta.cli
  • Regional population context: USGS governmental units overlay — county totals (sum within county, then across counties; avoids double-count from overlapping polygons).

SWAT+ in Massachusetts — common questions

  • How do I run SWAT+ in Massachusetts? Use SWATGenX to screen basins in Massachusetts on the Watershed Explorer map, then queue a SWAT+ model build for a USGS gage, catalog HUC12, or HUC8. The platform assembles national datasets into a SWAT+ Editor package without manual QSWAT+ desktop prep for each basin. The sample model on this page is Narragansett (USGS 01109090).
  • What is the difference between SWAT and SWAT+ in Massachusetts? SWAT (legacy) and SWAT+ (current process-based watershed model) both support long-term hydrology and water-quality studies in Massachusetts. SWATGenX targets SWAT+ and delivers reproducible, high-resolution projects on NHDPlus HR hydrography.
  • Can SWATGenX build SWAT+ models for Massachusetts watersheds? Yes. SWATGenX covers CONUS, including Massachusetts, with the same national data stack (WBD, NHDPlus HR, PRISM, NLCD, gSSURGO). Each state page documents a sample basin snapshot from a real SWATGenX build; open the live map at https://www.swatgenx.com/watershed-workspace to model your own watershed.
  • Is SWAT+ modeling in Massachusetts free on SWATGenX? Signed-in users can explore Massachusetts on the map and use tiered quotas for reports and model builds. See https://www.swatgenx.com/pricing for Basic vs Pro limits; Pro adds optional cloud calibration where enabled.

Open Narragansett in Watershed Explorer

Preview uses the USGS WBD boundary with NHDPlus HR context, zoomed to basin extent on a Streets-style basemap. Follow the card into the live workspace (HUC8 01090004).