Watershed Characterization Service
Description
The Watershed Characterization Service provides a variety of information on NHDPlus 2.1 hydrologic features. When provided with an identifier the service will respond with a report showing available size, stream flow, precipitation, temperature and NLCD land cover percentages for catchments and their cumulative upstream drainage area.
This service by default provides a report in HTML format for consumption in web browsers. Alternatively the data may be requested as a JSON object which also in turn may alternatively include spatial representations of the flowline and catchment features. To obtain a spatial representation of the entire upstream drainage area, use the Navigation Delineation service.
Input
Service Endpoint
http://ofmpub.epa.gov/waters10/Watershed_Characterization.Control
Input Parameters
The service requires one pComID, pPermanentIdentifier or pFeatureID parameter valaue. All other parameters are optional and provided for customizing the alternative JSON output format. The default HTML report output is intended to be consumed as a web page.
HTML Examples
- http://ofmpub.epa.gov/waters10/Watershed_Characterization.Control?pComID=4795168
- http://ofmpub.epa.gov/waters10/Watershed_Characterization.Control?pPermanentIdentifier=30763480
- http://ofmpub.epa.gov/waters10/Watershed_Characterization.Control?pFeatureID=-504160
JSON Examples
- http://ofmpub.epa.gov/waters10/Watershed_Characterization.Control?pComID=4795168&optOutFormat=JSON&optOutPrettyPrint=0
- http://ofmpub.epa.gov/waters10/Watershed_Characterization.Control?pPermanentIdentifier=30763480&optOutFormat=JSON&optOutPrettyPrint=0&optOutGeomFormat=GEOJSON
- http://ofmpub.epa.gov/waters10/Watershed_Characterization.Control?pFeatureID=-504160&optOutFormat=JSON&optOutPrettyPrint=0&optOutGeomFormat=GEOJSON&optOutCS=EPSG:3857
| Parameter | Description |
|---|---|
| pComID | The NHDPlus ComID identifier of the flowline feature. ComIDs are integer values assigned by NHDPlus to hydrologic features in the dataset. |
| pPermanentIdentifier | The NHDPlus Permanent_Identifier value of the feature. Currently only Hawaii, Puerto Rico and the US Virgin Islands utilize permanent identifiers in NHDPlus. If in doubt, use the ComID to reference NHDPlus hydrology. Permanent Identifiers are string values of a maximum length of 40 characters. The values may vary being in some cases character representations of the numeric ComID, in other cases a character representation of a unique integer value and in other cases a 38 character global unique identifier. However the value is always unique to the feature. |
| pFeatureID | The NHDPlus FeatureID identifier of the catchment feature. FeatureIDs are integer values assigned by NHDPlus to catchments in the dataset. Positive values always match to the ComID of the catchment's associated flowline. A negative value indicates the catchment is a sink without an associated flowline. In this case the information provided by the service is limited to the single catchment only. |
| optOutFormat | Optional parameter: either HTML or JSON to indicate the type of output requested from the service, the default value is HTML. |
| optOutPrettyPrint | Optional integer parameter for JSON format. If provided will return JSON results formatted for visual inspection with line breaks and indented three spaces multiplied by the value of the parameter. The default action is to provide compact unformatted JSON. |
| optOutGeomFormat | Optional parameter for JSON format. If provided with value GEOJSON, the service will return the geometry of the flowline and catchment in GEOJSON format. The default action is to forgo providing geometries in the output. |
| optOutCS | Optional parameter for JSON format and GEOJSON output. If provided with a value as defined under common http service parameters here, the resulting GEOJSON representation of the features will be projected to that coordinate reference system. The default is to provide GEOJSON in the NAD83 geodetic coordinate reference system (EPSG:4269). |
| optOutPruneNumber | Optional parameter for JSON format and GEOJSON output. If provided then coordinates of the GEOJSON features will be truncated to the number of digits provided. Depending on the user's need for precision (as well as the coordinate system utilized in optOutCS), clipping numeric coordinates to 8 or 12 digits of precision may lower the size of the service payload. Truncating too many digits may result in duplicated vertices which may or may not affect how the feature is utilized. |
| optJSONPCallback | Optional parameter for JSON format to allow consumption of the service as JSONP. |
Output
The default HTML report is intended to be self-explanatory with additional information being available from the NHDPlus user guide Exit.
For the alternative JSON output, the output object returned is flat with the following fields which attempt to closely follow existing NHDPlus dataset naming conventions.
| Name | Data Type | Description | Source |
|---|---|---|---|
| permanent_identifier | String | The Permanent_Identifier identifier of the flowline feature. This value will be null when the input parameter is a sink FeatureID. | NHDSnapshot NHDFlowline |
| comid | Integer | The ComID identifier of the flowline feature. This value will be null when the input parameter is a sink FeatureID. | NHDSnapshot NHDFlowline |
| reachcode | String | The Reach Code value of the flowline feature. This value will be null when the input parameter is a sink FeatureID. | NHDSnapshot NHDFlowline |
| fmeasure | Double | The From Measure value of the flowline feature indicating the percentage of the reach measure at which this feature begins. | NHDSnapshot NHDFlowline |
| tmeasure | Double | The To Measure value of the flowline feature indicating the percentage of the reach measure at which this feature ends. | NHDSnapshot NHDFlowline |
| featureid | Integer | The FeatureID value of the catchment feature. If the feature examined does not have a matching catchment feature, then this value will be null. | NHDPlusCatchment Catchment |
| gnis_name | String | The GNIS Name value of the flowline feature. | NHDSnapshot NHDFlowline |
| streamorder | Integer | The Modified Strahler stream order value of the flowline. |
NHDPlusAttributes PlusFlowlineVAA |
| streamlevel | Integer | The NHDPlus stream level value of the flowline. | NHDPlusAttributes PlusFlowlineVAA |
| startflag | Integer |
Flag indicating the headwater status of the flowline. 0 –feature is not a headwater flowline 1 –feature is a headwater flowline |
NHDPlusAttributes PlusFlowlineVAA |
| Q0001E | Double | Extended unit runoff method flow from gage adjustment. | EROMExtension EROM_MA0001 |
| mavelv | Double | Vogel Method Mean Annual Velocity (fps) at bottom of flowline using Jobson Method (1996) with MAFlowV. | VogelExtension VogelFlow |
| cumdrainag | Double | Total upstream cumulative drainage area, in square kilometers, at the downstream end of the flowline feature. | NHDPlusAttributes CumulativeArea |
| cumtempvc | Double | Mean annual temperature in area upstream of the bottom of flowline in degrees centigrade * 100. Note that the HTML report divides this value by 100 for human readability but the original NHDPlus value is preserved in the JSON output. | VPUAttributeExtension CumTotTempMA |
| cumprecipvc | Double | Mean annual precipitation in area upstream of the bottom of flowline in millimeters * 100. Note that the HTML report divides this value by 100 for human readability but the original NHDPlus value is preserved in the JSON output. | VPUAttributeExtension CumTotPrecipMA |
| cumnlcd_11 | Double | Area-weighted percent of NLCD class 11, Open Water, occurring in cumulative drainage area upstream of the bottom of flowline. | VPUAttributeExtension CumTotNLCD2011 |
| cumnlcd_21 | Double | Area-weighted percent of NLCD class 21, Developed, Open Space, occurring in cumulative drainage area upstream of the bottom of flowline. | VPUAttributeExtension CumTotNLCD2011 |
| cumnlcd_22 | Double | Area-weighted percent of NLCD class 22, Developed, Low Intensity, occurring in cumulative drainage area upstream of the bottom of flowline. | VPUAttributeExtension CumTotNLCD2011 |
| cumnlcd_23 | Double | Area-weighted percent of NLCD class 23, Developed, Medium Intensity, occurring in cumulative drainage area upstream of the bottom of flowline. | VPUAttributeExtension CumTotNLCD2011 |
| cumnlcd_24 | Double | Area-weighted percent of NLCD class 24, Developed, High Intensity, occurring in cumulative drainage area upstream of the bottom of flowline. | VPUAttributeExtension CumTotNLCD2011 |
| cumnlcd_31 | Double | Area-weighted percent of NLCD class 31, Barren Land, occurring in cumulative drainage area upstream of the bottom of flowline. | VPUAttributeExtension CumTotNLCD2011 |
| cumnlcd_41 | Double | Area-weighted percent of NLCD class 41, Deciduous Forest, occurring in cumulative drainage area upstream of the bottom of flowline. | VPUAttributeExtension CumTotNLCD2011 |
| cumnlcd_42 | Double | Area-weighted percent of NLCD class 42, Evergreen Forest, occurring in cumulative drainage area upstream of the bottom of flowline. | VPUAttributeExtension CumTotNLCD2011 |
| cumnlcd_43 | Double | Area-weighted percent of NLCD class 43, Mixed Forest, occurring in cumulative drainage area upstream of the bottom of flowline. | VPUAttributeExtension CumTotNLCD2011 |
| cumnlcd_51 | Double | Area-weighted percent of NLCD class 51, Dwarf Scrub, occurring in cumulative drainage area upstream of the bottom of flowline. | VPUAttributeExtension CumTotNLCD2011 |
| cumnlcd_52 | Double | Area-weighted percent of NLCD class 52, Shrub/Scrub, occurring in cumulative drainage area upstream of the bottom of flowline. | VPUAttributeExtension CumTotNLCD2011 |
| cumnlcd_71 | Double | Area-weighted percent of NLCD class 71, Grassland/Herbaceous, occurring in cumulative drainage area upstream of the bottom of flowline. | VPUAttributeExtension CumTotNLCD2011 |
| cumnlcd_72 | Double | Area-weighted percent of NLCD class 72, Sedge/Herbaceous, occurring in cumulative drainage area upstream of the bottom of flowline. | VPUAttributeExtension CumTotNLCD2011 |
| cumnlcd_73 | Double | Area-weighted percent of NLCD class 73, Lichens, occurring in cumulative drainage area upstream of the bottom of flowline. | VPUAttributeExtension CumTotNLCD2011 |
| cumnlcd_74 | Double | Area-weighted percent of NLCD class 74, Moss, occurring in cumulative drainage area upstream of the bottom of flowline. | VPUAttributeExtension CumTotNLCD2011 |
| cumnlcd_81 | Double | Area-weighted percent of NLCD class 81, Pasture/Hay, occurring in cumulative drainage area upstream of the bottom of flowline. | VPUAttributeExtension CumTotNLCD2011 |
| cumnlcd_82 | Double | Area-weighted percent of NLCD class 82, Cultivated Crops, occurring in cumulative drainage area upstream of the bottom of flowline. | VPUAttributeExtension CumTotNLCD2011 |
| cumnlcd_90 | Double | Area-weighted percent of NLCD class 90, Woody Wetlands, occurring in cumulative drainage area upstream of the bottom of flowline. | VPUAttributeExtension CumTotNLCD2011 |
| cumnlcd_95 | Double | Area-weighted percent of NLCD class 95, Emergent Herbaceous Wetlands, occurring in cumulative drainage area upstream of the bottom of flowline. | VPUAttributeExtension CumTotNLCD2011 |
| cumnlcd_missing | Double | Derived field representing percentage of missing NLCD data divided by total area of cumulative drainage area upstream of the bottom of flowline. For use in displaying the percentage of missing data. | Derived |
| areasqkm | Double | Area in square kilometers of the catchment. | NHDPlusCatchment Catchment |
| tempv | Double | Mean annual temperature in degrees centigrade * 100 for catchment. Note that the HTML report divides this value by 100 for human readability but the original NHDPlus value is preserved in the JSON output. |
NHDPlusAttributeExtension IncrTempMA |
| precipv | Double | Mean precipitation in millimeters * 100 for catchment. Note that the HTML report divides this value by 100 for human readability but the original NHDPlus value is preserved in the JSON output. | NHDPlusAttributeExtension IncrPrecipMA |
| nlcd_11 | Double | Area-weighted percent of NLCD class 11, Open Water, occurring in catchment. | VPUAttributeExtension IncrNLCD2011 |
| nlcd_21 | Double | Area-weighted percent of NLCD class 22, Developed, Open Space, occurring in catchment. | VPUAttributeExtension IncrNLCD2011 |
| nlcd_22 | Double | Area-weighted percent of NLCD class 22, Developed, Low Intensity, occurring in catchment. | VPUAttributeExtension IncrNLCD2011 |
| nlcd_23 | Double | Area-weighted percent of NLCD class 23, Developed, Medium Intensity, occurring in catchment. | VPUAttributeExtension IncrNLCD2011 |
| nlcd_24 | Double | Area-weighted percent of NLCD class 24, Developed, High Intensity, occurring in catchment. | VPUAttributeExtension IncrNLCD2011 |
| nlcd_31 | Double | Area-weighted percent of NLCD class 31, Barren Land, occurring in catchment. | VPUAttributeExtension IncrNLCD2011 |
| nlcd_41 | Double | Area-weighted percent of NLCD class 41, Deciduous Forest, occurring in catchment. | VPUAttributeExtension IncrNLCD2011 |
| nlcd_42 | Double | Area-weighted percent of NLCD class 42, Evergreen Forest, occurring in catchment. | VPUAttributeExtension IncrNLCD2011 |
| nlcd_43 | Double | Area-weighted percent of NLCD class 43, Mixed Forest, occurring in catchment. | VPUAttributeExtension IncrNLCD2011 |
| nlcd_51 | Double | Area-weighted percent of NLCD class 51, Dwarf Scrub, occurring in catchment. | VPUAttributeExtension IncrNLCD2011 |
| nlcd_52 | Double | Area-weighted percent of NLCD class 52, Shrub/Scrub, occurring in catchment. | VPUAttributeExtension IncrNLCD2011 |
| nlcd_71 | Double | Area-weighted percent of NLCD class 71, Grassland/Herbaceous, occurring in catchment. | VPUAttributeExtension IncrNLCD2011 |
| nlcd_72 | Double | Area-weighted percent of NLCD class 72, Sedge/Herbaceous, occurring in catchment. | VPUAttributeExtension IncrNLCD2011 |
| nlcd_73 | Double | Area-weighted percent of NLCD class 73, Lichens, occurring in catchment. | VPUAttributeExtension IncrNLCD2011 |
| nlcd_74 | Double | Area-weighted percent of NLCD class 74, Moss, occurring in catchment. | VPUAttributeExtension IncrNLCD2011 |
| nlcd_81 | Double | Area-weighted percent of NLCD class 81, Pasture/Hay, occurring in catchment. | VPUAttributeExtension IncrNLCD2011 |
| nlcd_82 | Double | Area-weighted percent of NLCD class 82, Cultivated Crops, occurring in catchment. | VPUAttributeExtension IncrNLCD2011 |
| nlcd_90 | Double | Area-weighted percent of NLCD class 90, Woody Wetlands, occurring in catchment. | VPUAttributeExtension IncrNLCD2011 |
| nlcd_95 | Double | Area-weighted percent of NLCD class 95, Emergent Herbaceous Wetlands, occurring in catchment. | VPUAttributeExtension IncrNLCD2011 |
| flowline_shape | Geometry | When requested, a GEOJSON geometry object representing the flowline. | NHDSnapshot NHDFlowline |
| catchment_shape | Geometry | When requested, a GEOJSON geometry object representing the catchment. | NHDPlusCatchment CatchmentSP |
Changelog
Version: 1.0 - Released: September 3, 2009
- Initial Release of NHDPlus 1.0 Watershed Characterization Report
Version: 2.0 - Released: February 27, 2014
- Updated to NHDPlus 2.1 (without NLCD information).
Version: 2.1 - Released: May 8, 2015
- Updated with new NHDPlus 2.1 NLCD information.