Documentation of Products Generated During the Mapping and Fish Data Component of the
"Fish and Ditch" Project
Adapted from Documentation provided by Ken Carrasco of King
County Department of Natural Resources, Water and Land Division. August
1998.
Contents:
Background
This is a documentation of the products generated by the Water and Land
Resources Division (WLRD) of the King County Department of Natural Resources
during the so-called "Fishes 'n Ditches" program overseen by the
County's Department of Development and Environmental Services (DDES). This
program is developing a permitting mechanism so that landowners in the County's
Agricultural Production Districts (APDs) can maintain the watercourses on
their property.
Three products were generated during the WLRD component of the program.
One is a ArcView shape file which is titled ditch.shp, and another
closely-linked product is an associated MS Access database called newfishdata.mdb.
The third product, a description of the research into the locations of materials
documenting the historical construction of ditches within King County, is
not discussed in this documentation.
Description of GIS Products
There are two GIS products resulting from the work performed by WLRD:
the ArcView shape file and the MS Access database. These products were presented
to DDES on August 6, 1998. Subsequently DDES converted the MS Access database
to dBASE standards. Also duplicate and empty records were purged from the
database.
The ArcView shape file (ditch.shp) maps the watercourse within the Agricultural
Production Districts. It was created as an ArcView "polyline"
shape file. All watercourses, regardless of size, duration of water within
them, or connections with other watercourses, were mapped.
The ArcView shape file CARTSTRM, dated 1997, was used as the starting
point for mapping the watercourses because 1) many of the watercourses in
the County have already been mapped on this shape file, and 2) the State
of Washington Department of Natural Resources uses this information to assign
stream types to watercourse. However, we found that many of the watercourses
documented in CARTSTRM were found to be false due to obsolete data or from
mapping at a different scale. (If land features are mapped at a standard
scale of 1:100,000, for example, the inherent imprecision which results
when the data is used at a scale of 1:24,000 will result in erroneous information.)
We edited CARTSTRM using aerial photographs ("orthophotographs")
which were taken in August of 1996 and with shape files depicting topographic
contour lines with 20 foot separations. We also compared our data with existing
paper maps, and incorporated water location data collected by the Tulalip
and Muckleshoot Tribes, from the non-profit organization Washington Trout,
or from other sources such as the appropriate Community or Basin Plans,
or from Conditions and Issues reports.
After these edits, the data was ground-truthed by driving all available
public roads in the APDs. Problems with the ground truthing arose because
of the lack of visibility of private land from the public road systems;
the areas of incomplete mapping are documented on the original data maps
kept on file at the Water and Land Resources Division.
So that fish data can be assigned to specific watercourse segments, or
in the event a landowner submits a request to maintain a specific location,
a numbering system to identify distinct areas was devised. This numbering
system is not intended to be a permanent method of watercourse identification,
and it is well-documented for an easy conversion to a more standardized
system. To facilitate this process, the segments were divided into small
portions because conversion to a new numbering system is far easier if small
segments can be combined into a larger segment rather than the reverse.
One such system is the SSHIAP ("Salmon and Steelhead Habitat Inventory
Analysis Project") currently being conducted by WDFW and the Northwest
Indian Fisheries Commission for which a new numbering system has been devised.
The use of Water Feature Number as well as a Segment number allows a
common Water Feature Number to identify a single water body, even in the
event of it being shown as discontinuous in the ArcView shape file. This
ability will be valuable in the Enumclaw APD if further research bears out
our suspicion that many of the discontinuous watercourses we mapped are
actually connected to each other.
The definition of the Water Feature Number and the Segment number as
"integers and tenths" (i.e. 0.0). This method permits the addition
of water features or segments which were not included during our work in
1998.
The Water Feature Number is a unique primary identifier, assigned to
the major tributaries from a mainstem, with the exception of the Enumclaw
area. This latter area has a significant number of watercourses or water
bodies which cannot be definitively assigned to either of the two major
rivers which pass through the area. Consequently, many Water Feature Numbers
were assigned to small water bodies in that area even if no obvious connection
could be determined.
The Segment Number is a secondary identifier which is unique among the
segments with a given Water Feature Number. It is used to separate and identify
specific reaches within a Water Feature Number. The default was 1.0 if only
a single segment was identifiable. In more complex water features, Segment
Numbers were assigned whenever the watercourse turned or encountered some
other topographical feature. Note: The Segment Numbers are consecutive starting
with 1.0; but if additional segment number were assigned during the review
of this data, the "tenths" were not assigned starting with .1,
but were assigned relative to their position on the water course to facilitate
the further addition of segments not previously identified on either side
of the new segment, and still maintain an ever increasing numeric sequence.
Note: even the major rivers and streams are truncated just beyond the
borders of the APDs as noted on many of the maps this project generated.
ArcView shape file "ditch.shp" feature attribute table data
definitions:
Field Name
|
Data Type
|
Data Description
|
| Shape |
polyline |
Geographic objects in the shape file that represent a given Water Feature
Number and Segment Number combination. |
| Waterfeatu |
number |
Water Feature Number: For each tributary/stream/ditch; decimals used for
features added later. |
| Segment |
number |
Segment Number: for each topographically separate part of the water feature;
default=1. |
| Apd |
number |
APD that the segment lies within: 1= Snoqualmie; 2=Sammamish; 3=Green River;
4=Enumclaw |
| Change |
number |
Flag that arc has been changed: 0=not changed; 1=changed |
| Key |
string |
Key to look up fish data in dBASE file: Composed of string representation
of Water Feature Number concatenated with " "and then the string
representation of Segment Number. |
dBASE file "fishdata.dbf" data definitions:
Field Name
|
Data Type
|
Data Description
|
| Key |
string |
Key to look up fish data in dBASE file: Composed of string representation
of Water Feature Number concatenated with " "and then the string
representation of Segment Number. |
| Apd |
string |
APD that the segment lies within: Samm(amish), Green (River), Snoq(ualmie),
or Enum(claw) |
| Waterfeat |
number |
Water Feature Number: For each tributary/stream/ditch; decimals used for
features added later. |
| Segment |
number |
Segment Number: for each topographically separate part of the water feature;
default=1. |
| Length |
number |
Segment Length: in Miles.Tenths, may be very approximate. |
| FishRec |
number |
Consecutive Number for each fish observation in a segment: default=1. |
| CommonName |
string |
Common Name of Water Feature: from maps or local inhabitants |
| Wria_no |
string |
WRIA number assigned by state or by King County's 1987 Basin Recon Study. |
| Type |
string |
Type based on fish use assigned by WA State DNR or WDFW: 1,2,3, 4 or 5 |
| Class |
number |
King County stream Class: 1, 2 w/salmonids, 2 w/out salmonids, or 3. |
| Shoreline |
string |
Shoreline designation. |
| Barrier |
string |
Presence of barrier in watercourse: I.e. culvert, steep gradient, driveway;
both artificial and natural. |
| Chanlized |
string |
Is the stream channelized: yes, no, perhaps, maybe |
| Habit_comm |
string |
Habitat Comments: restored, profuse reed canary grass; etc. |
| Sampled |
string |
Fish sampling ever done on this segment to our knowledge. |
| Species |
string |
Fish species present in segment: Coho, brown trout, small/largemouth base,
etc; unique for each record, may be multiple records for a given segment
in database. |
| Source |
string |
Source of Data for this fish record. |
| DataDate |
string |
Date the data was collected for this fish record. |
| Fish_Comm |
string |
Fish Comments: stocked by WDFW from Issaquah hatchery, feral fish from pond,
etc. |
| Rec_Water |
string |
Name of downstream receiving water body. |
| Flow_Direc |
string |
General compass direction of water flow if any: N, NW, stagnant, etc. |
| Hydro_Comm |
string |
Hydrology Comments: intermittent, changed in past year, etc |
| Misc_Comm |
string |
Miscellaneous Comments: comments that do not fit Habitat, Fish, or Hydro
Comments. |
Additions to the Products: Maintenance
Presently there are no mechanisms for maintaining these products. They
do, however, have the potential for storing information about the large
number of watercourses in the agricultural production districts. Coordination
of data between the shape file and database is critical.
A coordinator of information to be added or deleted from this database
should be selected. The addition or deletion of new watercourses to the
shape file will be relatively difficult; addition of fish data to the dBASE
file will be relatively easy.
Updated: January 2, 2002
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