Abstract:
This data layer represents lakes and reservoirs in the Russian River watershed. Features from the original source data (see Originator information) were selected based on their spatial location within the Russian River watershed in Sonoma and Mendocino counties in California (the study area boundary of the Russian River Watershed Adaptive Management Plan project). Additional waterbody polygon features were digitized using AirPhoto USA imagery.
This metadata file incorporates much of the information that was available in the metadata of the original source data. This information is indicated in quotation marks.
"The hydrography layer consists of flowing waters (rivers and streams), standing waters (lakes and ponds), and wetlands -- both natural and manmade. Two separate feature types are represented: polygons (areas) and lines. Polygon features have attribute codes that identify water bodies such as lakes, wide river segments, or swamps. Line features have attribute codes that represent streams or shorelines."
"Hydrography of the entire state is stored in 2 statewide coverages and in 33 separate ARC/INFO coverages or tiles. Statewide coverage names HYDRARCA (arc feature type) and HYDROPOLA (polygon feature type). The tiles coverages whose individual boundaries correspond to the USGS 1:250,000-scale quad series (see index coverage called hydroindexa and index diagram below). Coverage names consist of two unique characters plus a suffix -JHYSA. Most of the two-letter codes abbreviate a quad name, for example: RDJHYSA, for the Redding quad. The tiles are also numbered from 1 to 33, northwest to southest, andthis numeric code is contained in the item HYSNUM. A separate item, HSCKEY, contains a number unique to each arc within a tile. HSCKEY and HYSNUM are combined to form a primary key item, TDCKEY, which uniquely identifies every hydrography arc record statewide. "
Purpose:
This data layer was edited from its original source data set for inclusion in the Russian River Watershed Adaptive Management Plan (RRWAMP) and RRWAMP Baseline Watershed Assessment project. The intended use of this data layer in this project is to examine landscape or human factors to promote ecological health and sustainability within the Russian River watershed.
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Supplemental_Information:
The information included below is taken directly from the hydrogra.txt meatadata file that describes the hydrarca and hydrpola coverages developed by the Teale Data Center and the California Department of Fish and Game. This information is included for reference purposes, as it directly describes the original source data from which this layer was created.
"The following are subjective comments regarding this data.
The USGS DLG features of this layer are fairly complete. The density of
line work representing drainage networks appears to vary arbitrarily from
quad to quad, and there are discontinuities in lines depicting streams at
the edges of 100k quads. The geographic feature accuracy is fair.
Contiguous features are not always matched across map sheet boundaries.
The attribute completeness and accuracy of MAJOR/MINOR code pairs is good.
The US EPA River Reach File version 3-alpha (RF3-alpha) as archived at
Teale is an alpha release (prototype). As such, users are cautioned to
verify drainage network connectivity and water feature names before
undertaking extensive processing using RF3 data.
County lines (a separate Teale data layer) and hydrography lines are not reconciled with each other and discrepancies between the two will occur when a county boundary follows a water feature.
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SUPPLEMENTARY INFORMATION (courtesy of Calif. Department of Fish and Game)
In 1993, US EPA changed the Reach File table DS2 to DS3 and changed the MILE and related items from numeric type to character type. No data content changes were made. DFG compiled over 150 US EPA National Computer Center (NCC) CU-based DS3 tables into a set of 33 Teale tile-based tables in October 1996. DFG and cooperators have also made extensive corrections and additions of primary names/name codes in the DS3 tables. Forwarding
of these updates is expected in October 1996 to US EPA for inclusion in RF3 final processing.
The DS3 item UPDTSRC1 concatenates HYSNUM and HSCKEY (in that order) for those records that have a corresponding AAT record. UPDTSRC1 contains the value 9999 for DS3 records created by US EPA that have no corresponding record in the hydrography layer. UPDTSRC1 contains leading zeroes for
single-digit HYSNUM values. The Teale primary key, TDCKEY, is similar to UPDTSRC1 except that the concatenation order is HSCKEY + HYSNUM."
"The hydrography layer was assembled from data originally published by the U.S. Geological Survey (USGS) in Digital Line Graph (DLG-3) format. DLG-3 data were generated by USGS from 1:100,000-scale maps by manual digitizing and raster scanning. Approximately 3200 original USGS DLG files were processed by Teale to create the statewide hydrography data layer.
Edits to the original linework have been made during the data conversion by Teale from the original DLG-3 format to the ARC/INFO(tm) GIS format. Such changes include line movements (due to the map edge-matching process), minor corrections of attribute coding, and the closing of open polygons. Flow
direction for streams (feature type line) has also been added. Stream arcs are flagged (where item FLOW = 1) to indicate whether or not the direction of a given stream (line) has been defined and/or verified by Teale.
Hydrography of the entire state is stored in 2 statewide coverages and in 33 separate ARC/INFO coverages or tiles. Statewide coverage names HYDRARCA (arc feature type) and HYDROPOLA (polygon feature type). The tiles coverages whose individual boundaries correspond to the USGS 1:250,000-scale quad series (see index coverage called hydroindexa and index diagram below). Coverage
names consist of two unique characters plus a suffix -JHYSA. Most of the two-letter codes abbreviate a quad name, for example: RDJHYSA, for the Redding quad. The tiles are also numbered from 1 to 33, northwest to southest, and this numeric code is contained in the item HYSNUM. A separate item, HSCKEY,
contains a number unique to each arc within a tile. HSCKEY and HYSNUM are combined to form a primary key item, TDCKEY, which uniquely identifies every hydrography arc record statewide.
In 1992, the Teale hydrography data layer was sent upon request to the U.S. Environmental Protection Agency (US EPA) Office of Water for use as a basemap for the River Reach File version 3-alpha, also known as Reach File 3 or RF3-alpha. RF3 is US EPA's national hydrographic addressing system which contains unique water feature identification codes, names, and update documentation. RF3 was developed by Horizon Systems Corporation, under contract to the US EPA Office of Water. RF3 as archived at Teale consists of
a separate data table for each of the 33 Teale hydrography coverages, designated by the filename extension .DS3 (for example: RDJHYSA.DS3).
Hydrographic feature records in Teale's arc attribute tables (AAT) may be related (linked or joined) with corresponding RF3 records in DS3 tables on the item TDCKEY, which is present in both tables. Users are cautioned to verify the integrity of AAT - DS3 relations, as instances of many DS3 records relating to one AAT record are known to occur. Use of the relate item RF3RCHID in older versions of Teale AATs has been discontinued.
Statewide hydrographic feature records in Teale's polygon attribute table (PAT) may be related (linked or joined) with corresponding WRCB records in DAT table on the item wrcblakes, which is present in both PAT and DAT tables.
Reach File data, documentation, and technical support are provided through the US EPA Office of Water's STORET User Assistance Group at 800-424-9067. STORET is the US EPA's national water quality information system.
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UPDATES
December 1998
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Added in statewide polygon and line coverages, areas that were removed from Nevada and Arizona. The "STATECODE" attribute is also added to identify features
are:
1- Completely within CA
2- Partially with CA
3- Completely outside CA
PNAME and PNMCD attributes are added to the statewide line feature coverage.
attributes were extracted from the Reach File DS3 table.
NAME attribute is added to the STATEWIDE and the TILE (250K quad) polygon
coverages. Features included lakes, ponds, reservoirs, etc., the names were
manually entered based on the USGS's 100K quad maps. Names from the 24K quad
maps and the DFG's lakes coverage were used respectively to populate names
where names were not found on the USGS's 100K quad maps.
An additional database of lakes species/environment quality and ecological
factors was attached to the statewide polygon coverage. New item WRCBLAKES
in the PAT table will be is used to relate records to the HYDRPOLA.DAT table.
The DAT table came from DFG's lakes coverage lakes.DAT table. See table
description below for detail.
Added Appendix A (EPA River Reach File detail attribute descriptions) to the
documentation.
November 1998
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Posted current version of DS3 table with DFG's updates. Approximately 3400
records were updated. Names, name codes and RF3 identifiers were entered and
corrected by DFG in cooperation with the CA Rivers Assessment (CARA) program
at UC Davis. Updates were flagged in the item UPDTSRC2 in each DS3 table.
Lookup tables contain descriptions of the hydrographic features in the polygon
and line coverages. Tables are available for each of the 33 tile coverages and
the statewide Teale hydrography coverages. These separate lookup tables carry
all the MINOR codes and a description for each. Lookup tables are named
with an .LUT file name extension (for example: WEJHYSA.LUT).
May 1998
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Attribute updates in 6 quad coverages and in the statewide polygon coverage.
Enhanced MINOR1 and MINOR2 codes.
ACJHYSA
SJJHYSA
SOJHYSA
FOJHYSA
ZPJHYSA
MZJHYSA
April 1997
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New edition of River Reach (DS3) files. DFG and UC Davis enhanced RF3
attributes (primarily stream names and unique codes).
February 1997
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DFG reported inconsistency in DLG MINOR1 coding in Amboy (100k quad name),
99% of arcs were coded as WASHES. Apparently localized in a single 100K
quad. Modification were made so the coding consistent with the adjacent
quads. The changes were made to 2 coverages: NEJHYSA and KIJHYSA.
1996
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The California Department of Fish and Game (DFG) assembled the most current
RF3 tables from copies downloaded directly from US EPA's National Computer
Center (NCC) in September 1996. These DS3 tables, organized by hydrologic
basins, were appended and Teale tile-based tables extracted from them.
A significant volume of water feature names/name codes and RF3
identifiers were input and corrected by DFG in cooperation with the
California Rivers Assessment (CARA) program at UC Davis. All such updates
are flagged in the item UPDTSRC2 in each DS3 table."