The StreamCat Dataset: Accumulated Attributes for NHDPlusV2 (Version 2.1) Catchments for the Conterminous United States: Dam Density and Storage Volume

Metadata Updated: August 3, 2018

This dataset represents the dam density and storage volumes within individual, local NHDPlusV2 catchments and upstream, contributing watersheds based on National Inventory of Dams (NID) data. Attributes were calculated for every local NHDPlusV2 catchment and accumulated to provide watershed-level metrics.(See Supplementary Info for Glossary of Terms) The NID database contains information about the dam’s location, size, purpose, type, last inspection, regulatory facts, and other technical data. Structures on streams reduce the longitudinal and lateral hydrologic connectivity of the system. For example, impoundments above dams slow stream flow, cause deposition of sediment and reduce peak flows. Dams change both the discharge and sediment supply of streams, causing channel incision and bed coarsening downstream. Downstream areas are often sediment deprived, resulting in degradation, i.e., erosion of the stream bed and stream banks. This database was improved upon by locations verified by work from the USGS National Map (Jeff Simley Group). It was observed that some dams, some of them major and which do exist, were not part of the 2009 NID, but were represented in the USGS National Map dataset, and had been in the 2006 NID. Approximately 1,100 such dams were added, based on the USGS National Map lat/long and the 2006 NID attributes (dam height, storage, etc.) Finally, as clean-up, a) about 600 records with duplicate NIDID were removed, and b) about 300 records were removed which represented the same location of the same dam but with a different NIDID, for the largest dams (did visual check of dams with storage above 5000 acre feet and are likely duplicated - about the 10,000 largest dams) (see Data Sources for links to NID data and NHDPlusV2 data). The (dams/catchment) and (dam_storage/catchment) were summarized and accumulated into watersheds to produce local catchment-level and watershed-level metrics as a point data type (see Data Structure and Attribute Information for a description).

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Metadata Date May 22, 2018
Metadata Created Date February 8, 2018
Metadata Updated Date August 3, 2018
Reference Date(s) January 1, 2015 (publication)
Frequency Of Update asNeeded

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Harvested from Environmental Dataset Gateway FGDC CSDGM

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Resource Type Dataset
Metadata Date May 22, 2018
Metadata Created Date February 8, 2018
Metadata Updated Date August 3, 2018
Reference Date(s) January 1, 2015 (publication)
Responsible Party US Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory (NHEERL) (Point of Contact)
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Access Constraints Use Constraints: None. While EPA has used its best efforts to include complete and accurate information in the EME, EPA cannot be held responsible for errors or omissions and is not liable for any direct, indirect or consequential damages resulting from using this information. Reliance on the information contained in this system by any party cannot be used as a defense in any administrative or judicial proceeding. In such proceedings, the specific language of the relevant regulation or statute is binding. Acknowledgement of the EPA would be appreciated., Access Constraints: None.
Bbox East Long -66.5
Bbox North Lat 49.5
Bbox South Lat 24.5
Bbox West Long -125
Coupled Resource
Frequency Of Update asNeeded
Harvest Object Id 83dd12ee-0ffe-4029-8297-7cf822a6534a
Harvest Source Id d0d72986-7693-406b-b71d-840540909711
Harvest Source Title Environmental Dataset Gateway FGDC CSDGM
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Metadata Type geospatial
Progress completed
Spatial Data Service Type
Spatial Reference System
Spatial Harvester True

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