Maryland-Delaware-D.C. Water Science Center

Data and Tools

Filter Total Items: 183
Date published: January 1, 2019

30 year (1981 - 2010) annual average number of occurrences of dry and wet events for the Conterminous United States and District of Columbia

This metadata record describes the annual average number of occurrences of dry and wet events during the 30-year period 1981 – 2010 for the conterminous United States. A wet event is defined as a period when the number of consecutive days with precipitation equals or exceeds 1 millimeter. A dry event is defined as a period when the number of consecutive days with precipitation equals 0 m

Date published: January 1, 2019

Attributes for NHDPlus version 2.1 catchments and modified routing of upstream watersheds for the conterminous United States: Combination of landuse and geology.

This tabular data represents the area of combined landuse and surficial materials for the conterminous United States linked to the NHDPlus version 2 data suite by the unique identifier COMID. The source data are the National Land Cover Dataset (NLCD) representing 2011 ground conditions (Homer, 2013) , and the "Map database for surficial materials in the conterminous United States%2

Date published: January 1, 2019

Attributes for NHDPlus Version 2.1 Reach Catchments and Modified Routed Upstream Watersheds for the Conterminous United States: Average Annual Water Balance Variables over the Period of Record, 2000-2014

This tabular data set represents annual water balance variables as described in Wolock and McCabe (2017) averaged over the years 2000 through 2014, compiled for the NHDPlus version 2.1 data suite (NHDPlusV2) for the conterminous United States. The variables included are: actual evapotranspiration (AET) , potential evapotranspiration (PET), precipitation (PPT), runoff

Date published: January 1, 2019

30 year (1981-2010) average of annual maximum duration of consecutive dry and wet days per event for the Conterminous United States and District of Columbia

This metadata record describes the average of annual maximum duration of consecutive dry and wet days per event, where precipitation totals are 0 or equal and exceeds 1 millimeters respectively, during the 30-year period 1981 – 2010 for the conterminous United States. A wet event is defined as a period when the number of consecutive days with precipitation equals or exceeds 1 millime

Date published: January 1, 2019

Attributes for NHDPlus Version 2.1 Flowlines for the Conterminous United States: Bankfull Hydraulic Geometry Related to Physiographic Divisions

This tabular data set contains information on bankfull depth, width and cross-sectional area for each NHDPlus version 2.1 data suite (NHDPlusv2) flowline (Moore and Dewald, 2016) for the conterminous United States. These data were created using regional regression equations outlined in Bieger and others (2015). The equations predict bankfull width, depth and cross-sectional are

Date published: January 1, 2019

Attributes for NHDPlus version 2.1 catchments and modified routing of upstream watersheds for the conterminous United States: 2012 Percent farm land in conservation program.

This metadata record describes a computed ratio of county acres of farmland reported in agricultural conservation programs to the total acres of farmland reported for the county. Acres in conservation programs are for the 2012 time period, and reported by survey from the U.S. Department of Agriculture, Farm Field Survey. Acres of total farmland were used from the U.S. Department of Agricultur...

Date published: January 1, 2019

Attributes for NHDPlus Version 2.1 Flowlines for the Conterminous United States: 2010 Public supply fresh water withdrawals, weighted by 2013 population served.

This metadata record describes estimates of public supply water withdrawals for 2010, weighted by the population served in 2013. Data were compiled for two spatial components of the NHDPlus version 2 data suite (NHDPlusv2) for the conterminous United States; 1) individual reach catchments and 2) reach catchments accumulated upstream through the river network. This dataset can be linke

Date published: January 1, 2019

Attributes for NHDPlus Version 2.1 Flowlines for the Conterminous United States:Lithology

This dataset contains generalized lithologic classes (rocktypes) as reassigned from the USGS state geologic map compilation for the conterminous United States (Anning and Ator, 2017; Schweitzer, 2011). Lithology was classified into 12 generalized categories and assigned to the catchments of the NHDPlusV2.1 network as a fraction of the unit within the catchment.

Date published: November 2, 2018

Urban sediment and fallout radionuclide input characteristics of Dead Run watershed in Catonsville, Maryland for 2017-2018

This metadata record documents two comma delimited tables that contain information on fallout radionuclides and urban sediments within Dead Run watershed in Catonsville, Baltimore County, Maryland. Measurements include radiological activity for rainwater and sediment samples, sediment particle size information, suspended sediment concentration measurements, elemental composition of sedi

Date published: October 5, 2018

Estimated nitrogen from septic for the conterminous United States, 2010 (SepN_CONUS_bg_2010)

This metadata record documents a rudimentary estimate of nitrogen from septic for the conterminous United States for 2010, derived from block-group 1990 and 2010 Decennial Census of Population and Housing data. Specifically, the data were computed from 1990 population and housing data where a ratio of the total population to the people on septic was obtained and applied to 2010 population dat...

Date published: October 2, 2018

Select Attributes for NHDPlus Version 2.1 Reach Catchments and Modified Network Routed Upstream Watersheds for the Conterminous United States

This metadata record describes a series of data sets of natural and anthropogenic landscape features linked to NHDPlus Version 2.1’s (NHDPlusV2) approximately 2.7 million stream segments, their associated catchments, and their upstream watersheds within the conterminous United States. The data were linked to four spatial components of NHDPlusV2: individual reach catchments, ri

Date published: September 26, 2018

Sediment and geomorphology data for Walnut Creek, Iowa

This metadata record covers 9 comma-delimited ascii files that contain 1) ten-minute discharge values, 2) mean daily discharge and computed sediment loads, 3) grain size percentiles, 4) radionuclide source sample results, 5) radionuclide target sample results,6) laboratory sample splits, 7) elemental analysis results of samples, 8) suspended-sediment measurements,