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Oregon Water Science Center Hydrologic Studies

Portland Basin Ground-Water Study (completed 1991)

 README

This file describes the electronic data files archived from the
Portland basin ground-water study conducted by the U.S. Geological Survey
in cooperation with the Oregon Water resources Department, City of Portland
Water Bureau, and Clark County, Washington between 1987 and 1991. The results
of this study are described in the reports listed in the references section at
the end of this file.

These files are organized under following major headings and have been
archived and compressed using the pkzip (ver. 2.50) utility. Files under
each heading have been zipped together:
 

FILE FORMATS AND NAMING CONVENTIONS

All files with the .doc extension are documentation for specific data files
that have the same root name. For example, heads.doc is the documentation file
for the heads.txt file.

All files with the .txt extension are ASCII text files.

All files with the .e00 extension are ARC/INFO export files. Export files have
no file compression. These files can be read by any text editor and imported by
most spreadsheet or database applications. Map coverages are prefixed with cov_
and have .c. in the file name. INFO files are prefixed with inf_ and have .i.
in the file name. All coverages are in UTM projection (zone 10) with coordinate
units of meters.These files are restored using the ARC/INFO IMPORT command,

Arc: IMPORT <option> <interchange file> <output>

where <option> is COVER for coverages (.c.) and INFO for info files (.i.).

ITEM NAMES

Note that the abbreviations for the hydrogeologic units in the basin (e.g. US for unconsolidated sedimentary aquifer) may vary between those used in the reports from the study and those that appear in the data files. The files names are consistent with the report, however some of the items in the files may reflect the older abbreviations. The old and new abbreviations are listed below:

BASEMAP FILES

Simple geographic themes. Most were derived from 1:100,000 scale digital line graphs (DLGs). All have been clipped to the study area boundary.

bound.c.e00--study area boundary
geog.c.e00--place names
roads.c.e00--major roads
streams.c.e00--major rivers and streams
twnrng.c.e00--township lines
sections.c.e00--section lines

HYDROGEOLOGIC UNIT MAPS

hydrogeol.c.e00--hydrogeologic unit map

The following coverages contain the digitized contours for top elevation and thickness for each of the hydrogeologic units mapped by the study. Contours are in units of feet. The -ID item in each coverage contains the contour value. For example, in coverage elev.tg.c, the item ELEV.TG.C-ID in the ARC/INFO .AAT file contains the contour level.

elev.tg.c.e00--elevation contours of the top of the Troutdale gravel aquifer
elev.c1.c.e00--elevation contours of the top of confining unit 1
elev.ts.c.e00--elevation contour of the top of the Troutdale sandstone aquifer
elev.c2.c.e00--elevation contours of the top of confining unit 2
elev.uf.c.e00--elevation contours of the top of the undiff. sedimentary unit
elev.sg.c.e00--elevation contours of the top of the sand and gravel aquifer
elev.or.c.e00--elevation contours of the top of the older rocks unit

thk.us.c.e00--thickness of the unconsolidated sedimentary aquifer
thk.tg.c.e00--thickness of the Troutdale gravel aquifer
thk.c1.c.e00--thickness of confining unit 1
thk.ts.c.e00--thickness of the Troutdale sandstone aquifer
thk.c2.c.e00--thickness of confining unit 2 (where SG is present)
thk.c2a.c.e00--thickness of confining unit 2 (where SG is absent)
thk.sg.c.e00--thickness of the sand and gravel aquifer
              (both coarse and fine subunits.
thk.uf.c.e00--thickness of the undifferentiated fine-grained sediments

MODEL GRID AND DATA

gridthk.c.e00--finite difference model grid coverage (polygon) with hydrogeologic unit thickness and other data for each model cell.
str.reach.c.e00--streams simulated with STR package. Intersected with grid.
str.segment.c.e00--streams simulated with STR package. NOT intersected with grid.
key.txt--key codes for each model (identifies hydrogeologic unit)
key.doc--explanation of key codes
layelev.txt--elevation of tops (and bottoms) of model layers
laythk.txt--thicknesses of model cells by layer.
grid.doc--field definitions for these files.
layhycon.txt--hydraulic conductivity by model layer.
 

WELL AND SPRING DATA FILES

Each of the more than 15,000 wells documented by driller's reports in the Portland basin in 1989, is included in the file, log.i. Each well was assigned a unique identifier, LOG-ID. Basic information from the driller's log is included in this file. Approximate locations, based on the reported township, range, section, and quarter section, are in the coverage, unlocated.c. Locations for the 1,500+ field-located wells are included in the coverage studywells.c. Additional information on these field-located wells, such as lithology, open intervals, etc, is included in the remaining files. Data in all files is elated by the LOG-ID value. The field located wells are those documented in McCarthy and Anderson (1990).

well.data.doc--data dictionary for well data files.
studywells.c.e00--point coverage of field-located wells
unlocated.c.e00--point coverage of non-field-located wells
log.i.e00--well log data from driller's report
drlr-lith.i.e00--coded lithology from driller's report
drlr-lith.doc--explanation of lithology codes
geol-lith.i.e00--top and bottom elevations for hydrogeologic units
hydcond.i.e00--estimated hydraulic conductivity from specific capacity data
aquifer.test.i.e00--aquifer test result summaries
obs.wells.i.e00--information on observation wells
obs88.wells.i.e00--Spring 1988 synoptic water levels measurements
oi.i.e00--open interval data
levels.i.e00--percentage open interval in each hydrogeologic unit
swl.i.e00--water level data
alt.i.e00--altitude of land surface at well
lat-long.i.e00--latitude, longitude and UTM meter coordinates for wells
pump88.i.e00--mean annual pumping rates, 1988
spr.log.i.e00--spring information with LOG-ID tied to studywells.c
spr.name.i.e00--spring names
spr.q.i.e00--spring discharge measurements
geophys.wells.i.e00--wells with borehole geophysical logs available

STEADY-STATE MODEL CALIBRATION TARGETS

Mean 1987-88 hydraulic heads (feet above sea level) used in steady-state calibration, by hydrogeologic unit.

headmap.txt--readme file for GIS files of 1988 measured heads from WSP 2470-A
us_headmap_c.e00--1988 heads in the Unconsolidated sedimentary aquifer (US)
tg_headmap_c.e00--1988 heads in the Troutdale gravel aquifer (TG)
ts_headmap_c.e00-- 1988 heads in the Troutdale sandstone aquifer (TS)
sg_headmap_c.e00--1988 heads in the sand and gravel aquifer (upper coarse-grained subunit, SC)
obshead.doc--field definitions for obshead.*.txt files.
obshead.or.txt--older rock unit (OR)
obshead.c2.txt--confining unit 2 (lower confining unit, C2)
obshead.sc.txt--sand and gravel aquifer (upper coarse-grained subunit, SC)
obshead.ts.txt--Troutdale sandstone aquifer (TS)
obshead.c1.txt--confining unit 1 (upper confining unit, C1)
obshead.uf.txt--undifferentiated fine-grained sediments (UF)
obshead.tg.txt--Troutdale gravel aquifer (TG)
obshead.us.txt--Unconsolidated sedimentary aquifer (US)
obshead.resid.txt--residuals of observed and simulated heads for 1987-88 time-averaged steady-state calibration. Statistical summary.
inf_heads88.i.e00--Spring 1988 heads. All in one INFO file with unit identified.
inf_lowflow.i.e00--Fall 1987, 1988 lowflow stream discharge measurements
lowflow.doc--description of items in info file
inf_obs.str.i.e00--stream package flux targets for steady-state calibration
obs.str.doc--description of items in info file

MISCELLANEOUS DATA

inf_riv.i.e00--river cell parameters, including estimated vertical hydraulic conductivity of river bed (KV), in feet per day.
inf_str.i.e00--stream cell parameters, including estimated verticaL hydraulic conductivity of stream bed (KV), in feet per day.
drywells.c.e00--drywells (sumps) per 40 acre parcel, 1987
pdx.run.log--model calibration run log

MODEL INPUT FILES

pdxpc.zip--all model input files for 1987-88 calibration period. Files are in ASCII format. See readme files within the .zip file for complete descriptions.

MODEL ARCHIVE

modarch.zip-----complete archive of all model input, output, programs and
                utilities. Includes both INFO and ASCII versions of input
                and output files for three simulations: 1) time-averaged
                steady-state, 1987-88, 2) pre-development, and 3) a
                hypothetical development scenario. This is an image of the
                official model archive maintained on the USGS computer system
                in the Oregon District (directory: /gwmarciv/wsp2470-b).
 

REFERENCES

Free copies of these publications are available, while they last, from the
Oregon District office of the USGS. Contact the Public Information Officer
at:

U.S. Geological Survey
10615 SE Cherry Blossom Drive
Portland, OR  97216
(503) 251-3201

Collins,C.,A., and Broad, T.M., 1993, Estimated average annual ground-water
 pumpage in the Portland Basin, Oregon and Washington, 1987-88: U.S. Geological
 Survey Water Resources Investigations Report 91-4018,26 p.

McCarthy, K.A., and Anderson, D.B., 1990, Ground-water data for the Portland
 Basin, Oregon and Washington: U.S. Geological Survey Open-File Report 90-126,
 56 p.

McFarland, W.D., and Morgan, D.S., 1996, Description of the ground-water flow
 system in the Portland Basin, Oregon and Washington: U.S.Geological Survey
 Water-Supply Paper 2470-A, 58 p.

Morgan, D.S., and McFarland, W.D., 1996, Simulation of the ground-water flow
 system in the Portland Basin, Oregon and Washington: U.S. Geological Survey
 Water-Supply Paper 2470-B, 83 p.

Snyder, D.T., Morgan, D.S., and McGrath, T.M., 1994, Estimation of ground-water
 recharge from precipitation, runoff into drywells, and on-site waste-disposal
 systems in the Portland Basin, Oregon and Washington: U.S. Geological Survey
 Water-Resources Investigations Report 92-4010, 34 p.

Swanson, R.D., McFarland, W.D., Gonthier, J.B., and Wilkinson, J.M., 1993, A
 description of hydrogeologic units in the Portland Basin, Oregon and
 Washington: U.S.Geological Survey Water-Resources Investigations
 Report 90-4196, 56 p.

Portland Basin Ground-Water Study page
Oregon Water Science Center Studies Page