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Navigation Delineation Service


Description

The Navigation Delineation service is a service that builds upon the Navigation Service to provide an areal representation of the navigation process by linking navigated flowlines to associated areal geographies. In most cases the primary areal feature associated with NHD flowlines are the NHDPlus catchments. However the service is designed to be expanded in future versions to return results for other associated areal coverages such as Watershed Boundary Dataset (WBD) or Tiger Political layers.

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Usage Scenarios

TMDL Watershed Characteristics

Problem Statement: Reviewing a TMDL for a single listed water and pollutant.

Desired Information: Upstream drainage basin watershed characteristics for land areas that drain to surface water features within 50 miles of the downstream end of the listed water. Land use, impervious surface, population density, etc. are all data layers that are desired and can be generated by overlaying the returned drainage basin with the appropriate spatial layer. NOTE: land use characteristics based on the NHDPlus dataset are returned with the basin.

Information Returned from Service: Drainage basin polygon with land use characteristics.

Code Samples

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Input Parameters

Parameter Datatype Required Description
pNavigationType String True 'UM' for upstream mainstem navigation
'UT' for upstream with tributaries navigation
'DM' for downstream mainstream navigation
'DD' for downstream with divergences navigation
'PP' for point-to-point navigation 
pStartComID Integer False NHDPlus flowline ComID integer value to begin navigating from.  Users must provide either a starting ComID, Permanent Identifier, Reach Code or Hydrosequence parameter to indicate the starting location.
pStartPermanentIdentifier String False NHDPlus flowline Permanent Identifier string value to begin navigating from.  Users must provide either a starting ComID, Permanent Identifier, Reach Code or Hydrosequence parameter to indicate the starting location.
pStartReachcode String False NHDPlus reach code to begin navigating from. Users must provide either a starting ComID, Permanent Identifier, Reach Code or Hydrosequence parameter to indicate the starting location.
pStartHydrosequence Integer False NHDPlus hydrosequence integer value to begin navigating from.  Users must provide either a starting ComID, Permanent Identifier, Reach Code or Hydrosequence parameter to indicate the starting location.
pStartMeasure Number False Measure on the NHDplus flowline or reach to begin navigating from. Must be between 0 and 100 inclusive, or NULL. A value of null means that a measure will be calculated to be either the bottom or the top of the NHD flowline. (depending on whether the navigation type is upstream or downstream and whether it is a start or stop measure). 
pStopComID Integer False For Point-to-Point navigation only.  NHDPlus flowline ComID integer value to stop navigating at.  Users must provide either a stop ComID, Permanent Identifier, Reach Code or Hydrosequence parameter to indicate the ending location.
pStopPermanentIdentifier String False For Point-to-Point navigation only.  NHD flowline Permanent Identifier string value to stop navigating at.  Users must provide either a stop ComID, Permanent Identifier, Reach Code or Hydrosequence parameter to indicate the ending location.
pStopReachcode String False For Point-to-Point navigation only.  NHD reach code to stop navigating at.  Users must provide either a stop ComID, Permanent Identifier, Reach Code or Hydrosequence parameter to indicate the ending location.
pStopHydrosequence Integer False For Point-to-Point navigation only.  NHDPlus hydrosequence to stop navigating at.  Users must provide either a stop ComID, Permanent Identifier, Reach Code or Hydrosequence parameter to indicate the ending location.
pStopMeasure Number False For Point-to-Point navigation only.  Measure on the NHD reach code to stop navigating at. Must be between 0 and 100 inclusive, or NULL. 
pMaxDistance Number False Distance in kilometers to limit navigatation. If pMaxDistance or pMaxFlowtimeDay is not provided the full extent of the navigation will be returned.  For certain configurations in large networks this is likely to timeout or otherwise fail to return results. 
pMaxFlowtimeDay Number False Flow time in days to limit navigatation. If pMaxDistance or pMaxFlowtimeDay is not provided the full extent of the navigation will be returned.  For certain configurations in large networks this is likely to timeout or otherwise fail to return results.  At this time limiting results by flow time is non-functional. 
pFeatureType String False The areal feature type to associate with the flowline results and return. The default value is 'CATCHMENTSP' returning watersheds comprised of NHDPlus simplified catchments.  Use 'CATCHMENT' to return NHDPlus detailed catchments.  Setting this value to CATCHMENT will preclude the use of precached watersheds.
pOutputFlag String False FEATURE/FLOWLINES/BOTH - Flag to indicate which geometries are returned in the output. The default value is 'FEATURE'.  Setting this value to FLOWLINES or BOTH will preclude the use of precached watersheds.
pAggregationFlag String False TRUE/FALSE/BOTH - Flag to indicate whether to aggregate feature geometries in the output. Note that the delineated geometry of the feature type is considered a single feature thus non-aggregated results will be returned as single multipolygon geometry. The default value is 'TRUE'.  Setting this value to FALSE or BOTH will preclude the use of precached watersheds.
pFlowlineLists String False TRUE/FALSE - Flag to indicate whether to populate the catchment featureids and flowline reach code lists.  Setting this value to TRUE will preclude the use of precached watersheds.

Additional parameters specific to HTTP services are listed in the WATERS HTTP Services documentation.

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Output Return Object

ow_delineated_basin 

The output format for this service is JSON with GEOJSON formatted geometries.

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HTTP Service

Resource Location
Runtime Endpoint http://ofmpub.epa.gov/waters10/NavigationDelineation.Service

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Changelog

Version: 3.0 1- Released: April 21, 2014

  • pMaxTime parameter removed as NHDPlus v2.1 does not support time of travel calculations at this time.

Version: 3.0 - Released: February 03, 2014

  • SOAP version of the service decommissioned.

Version: 1.0 - Released: August 31, 2009 

  • Initial Release of HTTP Service

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