General Information

Project area general description

The state of South Dakota

Are any areas excluded?

Missouri River and some waterbodies excluded.

Types of flow statistics available

peak flows

ArcGIS version used for processing

Originally 9.1, with some updates using 9.2 and 9.3

Was TopoGrid used to process DEMs?

Yes

DEM and derivatives projection (general description)

NAD 1983 custom Albers in meters (central meridian is -100.0, standard parallels are 29.5 and 45.5, latitude of origin is 23.0)

DEM and derivatives (fdr, fac, etc.) resolution

 10 m

DEM source

NED 2004

Hydrography source

High-resolution NHD  1:24,000-scale

Hydrologic unit "walls" source

WBD

Gage basin boundaries source

For some gages, manually-digitized lines were available delineating a watershed boundary from the gage to the nearest huc12 boundary

Interactive map snapping tolerance

3 cells

 

Basin Characteristics Methods and Sources

Name

Description

Computation method

Data source

Report

Variable label in report

DRNAREA

Total drainage area in square miles

Basin area

10M DEM and 10M flow direction grid

Sando, (1998)

A

 

 

 

 

CSL10_85

Channel 10-85 slope in feet per mile

Basin Stream Slope

Computed using StreamSlope ArcHydro tool

Sando, (1998)

S

 

 

 

 

PII

Precipitation Intensity Index, 24 Hour 2 year Precipitation - 1.5 inches

At outlet

Computed from a grid developed based on U.S. Weather Bureau (1961) Rainfall Frequency Atlas of the United States: Technical Paper 40

Sando, (1998)

PII

 

 

 

 

CONTDA

Contributing Drainage Area = DRNAREA – non contributing drainage area

Basin area

Computed by subtracting NONCONTDA from DRNAREA

Sando, (1998)

CA

 

 

 

 

NONCONTDA

Area covered by non-contributing drainage area

Basin area

Computed using grid of non-contributing area

 

 

 

 

BSLDEM10M

Mean basin slope in percent, computed from 10-meter DEM

Basin slope

Computed using basin slope ArcHydro tool

 

 

 

 

PERIM

Perimeter in miles

Basin perimeter

Computed using the perimeter of the basin

 

 

 

 

LFPLENGTH

Length of associated Longest Flow Path in miles

Basin flow path

Computed using the LongestFlowPath ArcHydro tool

 

 

 

 

ELEVMAX

Maximum elevation in feet

Basin max elevation

Computed using 10m DEM

 

 

 

 

RELIEF

Maximum - minimum elevation, in feet

Basin average

Computed by subtracting the min elev in basin using DEM from the max elev in basin using DEM

 

 

 

 

COMPRAT

Compactness ratio, dimensionless

Computed

EQUATION=PERIM/(2*(3.14159*DRNAREA)^0.5)

 

 

 

 

RELRELFFM

Relative relief in feet per mile - RELIEF/PERIM

Computed

EQUATION=RELIEF/PERIM

 

 

 

 

SD_LIME

Percent total limestone from Sando and others (2008)

Basin percent

Sando and others (2008)

Sando and others, (2008)

 

 

 

 

LAKEAREA_NWI

Percent lakes and ponds as determined from the National Wetlands Inventory (2001)

Basin percent

National Wetlands Inventory (2001)

 

 

 

 

WETLAND_NWI

Percent wetlands as determined from the National Wetlands Inventory (2001)

Basin percent

National Wetlands Inventory (2001)

 

 

 

 

STORAGE_NWI

Percent storage (lakes, ponds, or wetlands), derived from the National Wetlands Inventory (2001)

Basin percent

National Wetlands Inventory (2001)

 

 

 

 

SD_LSTLZ

Percent Limestone Loss Zone from Sando and others (2008)

Basin percent

Sando and others (2008)

Sando and others, (2008)

 

 

 

 

SD_LSTHW

Percent Limestone Headwaters from Sando and others (2008)

Basin percent

Sando and others (2008)

Sando and others, (2008)

 

 

 

 

SD_CC

Percent Crystalline Core from Sando and others (2008)

Basin percent

Sando and others (2008)

Sando and others, (2008)

 

 

 

 

SD_AC

Percent Artesian Spring from Sando and others (2008)

Basin percent

Sando and others (2008)

Sando and others, (2008)

 

 

 

 

SD_ASLZ

Percent Loss Zone/Artesian Spring from Sando and others (2008)

Basin percent

Sando and others (2008)

Sando and others, (2008)

 

 

 

 

SD_BHEXT

Percent Black Hills Exterior from Sando and others (2008)

Basin percent

Sando and others (2008)

Sando and others, (2008)

 

 

 

 

SD_SNDHLS

Percent Sand Hills setting from Sando and others (2008)

Basin percent

Sando and others (2008)

Sando and others, (2008)

 

 

 

 

SLOPERAT

Slope ratio = channel slope / basin slope

Computed

Slope ratio = channel slope / basin slope

 

 

 

 

ELEV

Mean basin elevation, in feet

Computed

Computed from 10m DEM

Sando, (1998)

E

 

 

 

 

MINBELEV

Min elevation in feet

Basin min

Computed from 10m DEM

 

 

 

 

OUTLETELEV

Elevation at outlet, in feet

computed

Computed from 10m DEM

 

 

 

 

The South Dakota StreamStats introductory page here has additional information regarding the application, including links to reports, cooperators, and other explanatory information.