United States           Office of Water         EPA-823-R-00-024
        Environmental Protection        4305            May 2000
!>EPA  BASINS Case Study 1
         Cottonwood Creek Watershed,
         Idaho County, Idaho

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Introduction

EPA's Office of Science and Technology was requested by the Idaho Division of Environmental
Quality (TDEQ) to help develop a bacteria TMDL for Cottonwood Creek, Idaho using EPA's
BASINS software.  The technical goals of this project were to determine the source of the high
bacteria concentrations, estimate bacteria loadings, and determine load reductions needed to meet
State water quality criteria.  Another key objective of this project was to produce a case study to
demonstrate the use of BASINS in developing a TMDL. The technical goals of the study were
met and the State was able to issue the draft TMDL in accordance with the project's schedule.
How to Use this Case Study

The file Cottonwood modeling report.pdf, included in the BAS-CSl.zip file delivered with this
study, contains the complete report as submitted to the Idaho Department of Environmental Quality
(TDEQ).  The notes in the Step-by-Step Guide section of this study provide instructions on how to
reconstruct, in your own BASINS and NPSM projects, the work products described throughout the
modeling report. Unzip the BAS-CSl.zip file to a clean directory; make sure the Use Folder
Names option is selected in WinZip when extracting the data in order to preserve the directory
structure.  The files, as extracted from the zip file will then be in the same order as in the File
Index section of this study.  The Step-by-Step Guide includes instructions on where files are to be
placed in the BASINS directory structure, when required.  Readers, then, can follow along with
the steps taken during the course of the project by examining the available monitoring data;
building the BASINS project and customizing it to local conditions; setting up and performing an
initial NPSM watershed modeling run with default data sets; running the NPSM with the final
hydrology calibration; examining the assumptions and calculations performed outside of BASINS
for fecal coliform loading; running the model as calibrated for fecal coliform; and checking the
output against the bacteria monitoring data.

Note: The Step-by-Step Guide part of this report was written explicitly for those watershed
modelers who have had some exposure to BASINS in a BASINS training course, or through self-
paced training with the User Manual tutorial. Users of the Step-by-Step Guide not yet familiar
with BASINS are encouraged to use the user manual tutorial; the tutorial starts on page 4.3-3 of the
user manual  (how to create the BASINS tutorial project) and is found throughout the user manual
as the last text box in each section.
Modeling and Public Participation Process

The modeling and public participation process is represented graphically in Figure 1, below.
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Figure 1. Modeling and Public Participation Process: Cottonwood Creek Bacteria TMDL
     Conference Calls
        with TAG*
 Goal Identification
and Model Selection
                         Data Collection/ Data Mining
                           (IDEQ Studies, BASINS)
     Conference Calls
        with TAG*
       Idaho & EPA
         Review
 Data Compilation
    and Review
                              GIS Analysis and
                             Initial Model Setup
                            Watershed Modeling with
                                 NPSM/HSPF
                                  Model
                                Calibration
 Model Output
Stakeholder
  Review
                             Publication in Draft
                              TMDL Document
                              Public Comments
                      Publication of Final TMDL Document
     * - Technical Advisory Group
Apr., 1999

May

Jul.

Aug

Nov

Nov

Dec.
l

1999

1999

, 1999

, 1999

, 1999

1999
r
Jan., 2000
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This project included extensive stakeholder input and review. The TMDL development was a
cooperative venture resulting from numerous discussions and reviews from federal, state, and
tribal members, and local citizens.  Two local Watershed Advisory groups were established from
the stakeholders to review and advise on the development of the TMDL.

The first group, the Cottonwood Creek Watershed Advisory Group (WAG) was appointed by the
IDEQ Administrator in August, 1997 to fulfill the State regulatory requirements for public
participation, and to provide the needed community perspective on watershed management.
Members of the Watershed Advisory Group were selected from nominations from the local
community to represent specific stakeholders groups within the watershed (see below). The group
met 12 times at the BLM office in Cottonwood, Idaho and all meetings were open to the public.
                            Cottonwood Creek Watershed
                               Advisory Group (WAG)
                                   Nez Perce Tribe
                                     Idaho County
                                  City of Cottonwood
                              Livestock and Dairy Owners
                                     Recreation
                                       Business
                                     Agriculture
                                     Ag. Chemical
                                    Environmental
                                     Land Owners
The second group was the Cottonwood Creek Technical Advisory Group (TAG). The TAG dealt
with the technical, regulatory and policy issues of the Cottonwood Creek TMDL and included
representatives from the state and federal government, and the Nez Perce Tribe (see below).

During the course of this project, information was exchanged frequently with the IDEQ, as well as
between EPA Headquarters and EPA's Region 10 Offices. The Cottonwood Creek Technical
Advisory Group met via several conference calls to discuss data availability, modeling, and
preliminary results.  Memos and notes summarizing the meetings and telephone conferences were
issued by the IDEQ.
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                             Cottonwood Creek Technical
                                Advisory Group (TAG)
                                  EPA Headquarters
                                   EPA Region 10
                     EPA Region 10 Idaho Operations Office - Boise
                              Bureau of Land Management
                         Natural Resource Conservation Service
                             Soil Conservation Commission
                       Idaho Department of Environmental Quality
                           National Marine Fisheries Service
                                   Nez Perce Tribe
                              Idaho Department of Lands
                     Idaho County Soil Water Conservation District
Preliminary results of the project were presented as a case study at the EPA Regional TMDL
Coordinators Meeting held in Washington, D.C., and separately to a technical representative of
EPA's Office of Wetlands, Oceans and Watersheds.  Copies of draft and final documents were
reviewed by EPA management, and by EPA's Region 10 Idaho Operations Office - Boise. An
EPA environmental engineer traveled to Cottonwood, Idaho and met with the Technical Advisory
Group and the IDEQ, to review the preliminary watershed modeling results.  As a result of the
meeting, a number of changes were made to the input parameters to more realistically represent
local conditions and agricultural practices.  The models were then re-run and a number of new
scenarios were modeled based on suggestions from the TAG.

The report, Fecal Coliform TMDL Modeling Report: Cottonwood Creek Watershed, Idaho
County, Idaho (file cottonwoodmodeling report.pdf), containing detailed information on the
project was placed on file in the Idaho state docket and was made available for review by the
public. A summary document discussing input parameters, model calibration, model results, and
conclusions was also submitted to the State. This summary report was used as a component of the
State's Cottonwood Creek watershed TMDL report, later published as a public review draft.  The
draft TMDL was available for public review and comment at several locations.  Formal
notification was made through several local and regional newspapers and copies were provided to
each member of the various advisory groups. Written comments were accepted by the IDEQ.
Two public meeting were held, one in Cottonwood and one in  Lewiston, to summarize the
findings. Following the public comment period, the comments were addressed and responses
were provided in the appendix of the final TMDL document.
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Step-by-Step Guide

The page numbers, below, refer to the original Fecal Coliform TMDL Modeling Report for
Cottonwood Creek (cottonwoodmodeling_report.pdf) and are adjoined by text describing steps
you can take in a hands-on re-creation of the BASINS/NPSM projects used to perform the
Cottonwood Creek fecal coliform TMDL.  Note: you must have the BASINS 2.01 update installed
in order to load and run the NPSM project files included in the zip file.  Quality Assurance/
Quality Control discussions (QA/QC notes) are also provided where decisions on whether or not
to use a particular data set were made and/or where an original data set was modified to improve
quality.

p.2&3 - Bacteria data from each of the seven monitoring stations in the Cottonwood Creek
watershed  can be viewed by opening the files in the Bacteria Data folder. The data can be read in
a text editor or viewed in the NPSM Postprocessor: Open the NPSM Postprocessor and import
the data using the USGS Flow Data button.  The Postprocessor assumes the data is flow data since
it uses the USGS format and cgi extension; the data is actually fecal coliform concentration in units
of #/100ml. You can enter the water quality standard as a threshold value.  If using the 30-day
geometric mean standard, enter geometric mean for Statistical Method and 30 for Step; this re-
plots the data as a running 30-day geometric mean.

              QA/QC note: Bacteria measurements were collected by or for the State of
              Idaho and were reviewed by the Idaho Division Environmental Quality (IDEQ).
              Bacteria samples were collected as grab samples using sterilized 200 ml
              bottles from each of the seven water quality monitoring stations in the
              watershed.  Standard laboratory methods were used for the bacteria analysis and
              all analyses were performed in certified laboratories using the Membrane
              Filter Technique.

              Certified laboratories used in the water quality monitoring project included:
                      Antatek Labs, Inc, Moscow, Idaho
                      Analytical Sciences Laboratory, Moscow, Idaho
                      AAA Superior Laboratory, Cheney, Washington
                      Confluence Water Laboratory, Lewiston, Idaho
              Six percent of the samples (ten of the bacteria samples taken between April and
              June, 1997) were split into duplicates samples and analyzed separately for
              quality assurance. The difference between split samples ranged from 50-
              160%, with an average difference of 84% (Gilmore, 1998).

              Water quality observation data from BASINS were examined in this project.
              This data set contains actual water quality observations for a select combination
              of stations and parameters which are extracted from EPA's STOrage and
              RETRIEVAL (STORET) database. In addition, a direct search of EPA's
              STORET databases found several dozen water analyses reported for Stockney
              and Upper Cottonwood Creeks taken between 1973 and 1985. However, the
              Cottonwood Wastewater Treatment Plant was redesigned in  1995-96
              significantly reducing bacteria discharge to Upper Cottonwood Creek. Due to
              the limited nonpoint source loading data available during this time period, as
              well as due to the WWTP modifications, none of the early STORET data was


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              used in this project (USEPA, 1999B).

P. 3-5 - The Cottonwood WWTP flow and bacteria load data can be viewed in the cot bac.prj -
final bacteria calibration (baseline) file.  If you have BASINS installed on a drive letter other than
C:, you'll need to modify this file slightly prior to loading it into the NPSM. Open this file in a
text editor with search capabilities (such as Wordpad), search for "C:" and replace the C drive
letter with the drive letter to which you have BASINS installed. You'll have to do this twice, once
for the starter.def 'file location, and again for the cotton4.wdm file location. To view or run this
project on your computer, place the file in a new folder named cotton in the
BASINS\modelout\cotton directory, make sure the starter.def file that comes with the BASINS
system is in the BASINS\models\NPSM directory, and place the cotton4.wdm, cotton4.inf, and
cotton4.txt files in the BASINS\data\met_data directory. Open the  file in the NPSM, and click on
the Point Source button, then the Loads button, select Cottonwood WWTP from the Discharger
Name pull down list,  and click the Edit Data button.

              QA/QC note: The location of the Cottonwood WWTP was obtained from
              EPA's Industrial Facilities Discharge (IFD) database in BASINS, as opposed to
              the PCS coverage. The IFD database, contributed to by a number of
              organizations including federal, state, and interstate agencies, was designed and
              implemented in late 1970s to provide a comprehensive database of industrial
              and municipal point source surface water dischargers in the United States and
              includes the Permit Compliance System (PCS) (USEPA, 1998).

              Discharge data for the Cottonwood WWTP was provided by  the Cottonwood
              City Clerk. The record covered the period of discharge from November, 1996
              to March, 1999. The raw WWTP data provided a running total from which a
              daily flow in millions of gallons per day (MOD) had been calculated by the
              City. A number of simple math errors were discovered in this data and
              corrected. The daily flow data was then entered into an Excel spreadsheet and
              converted from MOD to cubic feet per second and reformatted.  The final data
              was provided to the IDEQ for review and then distributed to  other Cottonwood
              TMDL workgroups that needed flow data (Cottonwood, 1999).

              Only one other facility is permitted for discharge by EPA's NPDES program in
              the Cottonwood Creek watershed for discharge; The North Idaho Correctional
              Institution is permitted for a sewage system.  However, the IDEQ reported that
              the facility discharges to Lawyers Creek, in an adjacent watershed. Since it is
              not a source of pollution to the Cottonwood Creek watershed, it was not
              considered further in this project (IDEQ, 1999A).

p. 6-11 (Section 3)  - Data from each subsection is contained in or calculated from append3.XLS.
This file is a beta version of the EPA fecal coliform spreadsheet with some modifications made
specifically for this project.  The final version of the spreadsheet will be made available on the
BASINS web page and in Lotus format as well.

P. 12 - You can recreate the Cottonwood BASINS project on your computer, by downloading and
extracting the South Fork Clearwater Web Archive Data Files (17060305  core.exe,
17060305 dem.exe, and 17060305  rf3.exe from www.epa.gov/ost/basins/HUCS/17060305).


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Project the data set according to the projection parameters listed on page 16 in order to match the
projection of the local data sets.

P. 12 - The local land use data is provided in the landuse folder of the Spatial Data directory
(cttnland.dbf, cttnland.sbn, cttnland.sbx, cttnland.shp, and cttnland.shx). Add this to your
Cottonwood BASINS project as a BASINS land use; The original land use code is Minor7; The
original description field is landuse. You can add the legend created specifically for this project
by loading the cotlegnd.avl file. To do so, double click on the cttnland.shp theme, click the load
button, navigate to the cotlegnd.avl file location; click ok to load all classes and symbols, then
click the Apply button and close the legend editor.

P. 13 - The original Idaho DEQ watershed subdelineation is provided in the Delineated
Watersheds folder in the Spatial Data directory as files: (idsheds.dbf; idsheds.shp, and
idsheds.shx). The modified delineation which uses all seven monitoring stations as pour points is
located in the same folder (files rest2rf3.dbf, rest2rf3.sbn, rest2rf3.sbx, rest2rf3.shp, and
rest2rf3.shx).  Both data sets can be imported as BASINS watersheds, however, you need to
import the modified RF3 theme first (see next item). When importing the watersheds, select Reach
File, version 3, then Reach File,  V3, rf3ct rf. Watershed delineation is discussed in more detail
on page 23 of the modeling report.

Additional Spatial Data Coverages:
•      The bacteria monitoring stations coverage (idstations.dbf, idstations.shp, and
       idstations.shx) is located in the Spatial Data directory and can be added as an Other
       theme.  Coordinate information for the location of the bacteria sampling stations and gaging
       stations were provided by the IDEQ. Locations were derived from USGS 7 Va minute
       topographic maps.
•      The Nez Perce Reservation boundary files (nezperce.dbf,  nezperce.shp, and nezperce.shx)
       are located in the Spatial Data directory and can be added as an Other theme.
•      The Cottonwood WWTP location files (ptctwwtp.dbf, ptctwwtp.shp, andptctwwtp.shx)
       are also located in the Spatial Data directory and can be added as an Other theme.

P. 13 - The modified RF3 coverage is located in the RF3 folder in the Spatial Data directory (files
rfSctrd.dbf, rf3ct rd.sbn, rf3ct  rd.sbx, rf3ct rd.shp, and rfSctrd.shx).  The original RF3
coverage was modified to union separate segments and include the Level field as required for
watershed delineation with Pacific Northwest RF3  data (see page 7.1-9 in the BASINS User
Manual).  It contains only the RF3 segments relevant to the Cottonwood project (i.e. is clipped to
the area of interest). Add this theme as a BASINS Reach File, V3 theme.

p. 13 - Calculations of the hydrologic function table (Ftable) values for each reach segment in the
Cottonwood Creek watershed model are shown in the lotus spreadsheets in the Ftables directory.
These calculations are described in more detail on page 22 of the  modeling report.

P. 23-24 - The NPSM project file cot hyd.prj contains the final hydrology calibration for the
detailed Cottonwood Creek watershed model. Follow the directions given for the cot bac.prj file
in item p. 3'-5, on where to locate and how to modify (if necessary) the cot  hyd.prj file. In the

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Output Manager, select the Reaches radio button, select the Lower Cottonwood Creek (009)
subwatershed, and select the RO(1)(1) variable, in the RCHRESVHYDR module, for output. This
variable is the total outflow from the Lower Cottonwood Creek at the flow gage station (in cfs)
and is directly comparable to the data in the stat7A90-98.cgi file. You can reproduce Figure 1.
Hydrology Calibration at Lower Cottonwood Creek Gage Station (on page 19) by plotting
RO(1)(1) versus the stat7A90-98.cgi flow for the period 10/1/1996 to 5/30/1998. A default data
set, created based on the Tualatin River site in the HSPFParm database, is also included (file
tualatn.def). You can check the performance of the model using this  default data set by  saving the
cot hydr.prj file under a new name and opening that project, then loading the tualatn.def file as
the new default data file.

              QA/QC note: Analysis of the flow data by Jim Fitzgerald, EPA Region 10,
              concluded that high and low flows from the stations were being significantly
              over and under predicted, respectively. He did find a good correlation between
              discharge at the mouth of Lower Cottonwood Creek (Station 7) and the USGS
              gaging station at Lapwai Creek in a nearby watershed.  Using this linear
              relationship, he generated a new set of estimated flow data for 1974 to 1998.
              This new data set representing only the flow at the mouth of Lower
              Cottonwood Creek was the basis for which NPSM was calibrated and modeled.
              Because of the uncertainty in flow data from the upper monitoring stations,
              they were not used in the analysis (Carol Fox, IDEQ; Jim Fitzgerald, USEPA,
              pers com., 1999).

              It should also be noted that the BASINS - USGS gaging station database
              incorrectly lists a station on a tributary of the Upper Cottonwood Creek
              (USEPA, 1999A).  USGS station # 13341000, named faeNorth Fork Clear
              Water River, is not located in this watershed and no information concerning
              this station was used in this project.
P. 24-26 - The NPSM project file cot bac.prj contains the final bacteria calibration for the
detailed Cottonwood Creek watershed model. Again, to load this file on the NPSM follow the
directions for changing the drive letter (if necessary) and place the file in the appropriate directory
as described previously (item p. 3-5). You can reproduce Figure 2.  Fecal Coliform Calibration
for Lower Cottonwood Creek by comparing model output and measurement data for Lower
Cottonwood Creek. In the Ouput Manager, select the DQAL variable (in RCHRES/GQUAL for
the Lower Cottonwood Creek [009] subwatershed). Run the model and compare the DQAL output
against the stat7fc.cgi bacteria concentration data (input it as a USGS file, flow parameter) in the
NPSM Postprocessor. The append3.XLS file is the Excel spreadsheet used to calculate many  of
the numerous input parameters related to the bacteria calibration.  The last sheet in this worksheet
(PRJ Formatted Input) is how the MON-ACCUM (monthly accumulation rate) and MON-SQOLEVI
(monthly limiting storage) variables are transferred from the spreadsheet to the NPSM.  This sheet
is saved as a text file and the text file is opened in Wordpad. The entire contents of the text file are
copied to the buffer. Then the prj file is opened in a text editor (Wordpad) and the buffer is copied
to the appropriate location in the prj file.

P. 30 - You can reproduce the values in the Manure Application, Grazing Cattle column of Table

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7.  Stream Loading by Source (Billions fecal coliform per year [Bfc/year]) by outputting SOQO
for each subwatershed.  In the Output Manager, select the SOQO variable (PERLND/PQUAL) for
the All Pervious landuse for each subwatershed. After running the model, plot the variable, for a
one year period, in the NPSM Postprocessor and check the area under the curve. Other values in
Table 1 can be calculated, by hand or with a spreadsheet, from the data in the Point Sources
Pollutant Information screen of the NPSM.

p.  31 - The percent reduction and Load to Achieve WQ Std. (or Load Allocation) were generated
by iteratively modifying and running the uci file for the final bacteria calibration until the water
quality standard was met for each reach segment. The multiplication factor values in the
NETWORK block for POQUAL, (original values are the area of the land segment in acres) are
modified in the cttn47d.uci by multiplying the original values by (1-% reduction). Place this file
in  the BASINS\modelout\cotton directory (make sure there is & Reaches subdirectory). If BASINS
is  loaded on a drive other than C:, open the file in a text editor and modify the file paths in the
FILES block to reflect the correct drive letter.  Run the file through HSPF in dos mode using the
following command from the StartVRun menu: C:\Basins\models\Npsm\XNPSMllx.exe
C:\Basins\modelout\cotton\cttn47duci.  Check the output for each reach against the water quality
standard applicable to that reach.

P.  32-33 - The control scenarios were designed more for purposes of diagnosing the loading
problem as opposed to creating realistic potential controls. Once the effect of different source
categories is understood, the stakeholders can decide on an effective control strategy - by
proposing realistic controls that can be modeled to examine the actual impact in the model. The
controls on wading cattle, septic systems, and the WWTP were simulated by applying a multiplier
in  the Point Source Editor, Flow and LoadMutiplier Screen. Other scenarios (e.g. zero hog
manure) were re-created by modifying the fecal coliform spreadsheet, and copying the results to
the prj as described previously (item p. 24-26).  Open and run the NPSM project files,
corresponding with the  scenarios  listed in the File Index.  Again, each project file will need to be
modified if BASINS is  loaded on a drive other than C:.
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                                       File Index

Bacteria Data (Fecal coliform sample results):
       stall'fc.cgi - Stockney Creek;
       stat2fc.cgi - Upper Cottonwood Creek;
       stat3fc.cgi - Shebang Creek;
       stat4fc.cgi - South Fork Cottonwood Creek;
       statSfc.cgi - Long Haul Creek;
       stat6fc.cgi - Red Rock Creek; and
       stat?fc.cgi - Lower Cottonwood Creek.
Control Scenarios (NPSM project files)
       cotton48.prj - Scenario A;
       cottonSO.prj - Scenario B;
       cotton53.prj - Scenario C;
       cottonSS.prj - Scenario D;
       cotton57.prj - Scenario E; and
       cottonSS.prj - Scenario F.
Ftables (Hydrologic Function Tables)
       Long Haul. 123;
       Lower  Cottonwood. 123;
       Middle Cottonwood. 123;
       Middle Cottonwood 2.123;
       Red Rock. 123;
       Red Rock 2.123;
       S Fork Cottonwood. 123;
       S Fork Cottonwood 2.123;
       Shebang. 123;
       Stockney. 123;
       Upper  Cottonwood. 123;
       Upper  Cottonwood 2.123; and
       Upper  Cottonwood 3.123.
Spatial Data (Specific to Cottonwood  Creek Watershed):
       Delineated Watersheds
              (Original watershed delineations provided by IDEQ)
                    idsheds.dbf;
                    idsheds.shp; and
                    idsheds.shx.
              (Modified delineation corresponding with monitoring stations as pour points)
                    rest2rf3.dbf;
                    rest2rf3.sbn;
                    rest2rf3.sbx;
                    rest2rf3.shp; and
                    rest2rf3.shx.
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       Landuse
              (Legend for local Cottonwood land use data)
                    cotlegnd.avi.
              (Local Cottonwoood land use data)
                    cttnlanddbf,
                    cttnland.sbn;
                    cttnland.sbx;
                    cttnland.shp; and
                    cttnland.shx.
       Rf3 (Modified RF3 as required for subwatershed delineation)
                    r/3ct rddbf,
                    rf3ct rd.sbn;
                    rf3ct rd.sbx;
                    rf3ct rd.shp; and
                    rf3ctrd.shx.
       (Cottonwood monitoring stations)
              idstations.dbf;
              idstations.shp; and
              idstations.shx.
       (Nez Perce Reservation boundary)
              nezperce.dbf;
              nezperce.shp; and
              nezperce.shx.
       (Cottonwood WWTP)
             ptctwwtp.dbf,
             ptctwwtp.shp; and
             ptctwwtp.shx.
Weather Data (Site Specific Cottonwood WDM Data; place in BASINS\data\met_data)
       cotton4.inf\
       cotton4.sta; and
       cotton4.wdm.
(South Fork Clearwater Watershed Web Archive Data Files)
       17060305_core.exe;
       17060305 dem.exe; and
       17060305_rf3.exe.
append3.XLS - fecal coliform spreadsheet (beta) with project specific modifications.
cot bac.prj - final bacteria calibration (baseline).
cot hyd.prj - final hydrology calibration with full reach network.
Cottonwood modeling report.pdf - Fecal Coliform TMDL Modeling Report for Cottonwood
       Creek Watershed, Idaho County, Idaho, as submitted to Idaho DEQ
cttn47d.uci - modified uci file used in dos-only run for final percent tributary load reductions.
stat7A90-98.cgi - adjusted flow data from Lower Cottonwood Creek gage station.
tualatn.def- default data file that matches the HSPFParm Tualatin River project.
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                                    References

Carol Fox, IDEQ; Jim Fitzgerald, USEPA, pers com.,  1999. Regarding quality of flow data for
seven monitoring stations in Cottonwood Creek watershed.

Cottonwood, 1999. Unpublished flow data from City of Cottonwood Wastewater Treatment Plant
for the period of November, 1996 to March, 1999, Cottonwood, Idaho.

Gilmore, Shelly 1998. Cottonwood Creek Monitoring Program, Final Report, Resource
Planning Unlimited, Moscow, Idaho.

IDEQ, 1999 A. Idaho Division of Environmental Quality. Cottonwood Creek TMDL, Unpublished
draft April 30, 1999.  Compiled by IDEQ-LRO. Lewiston, ID.

USEPA, 1998. Meta Data for EPA/OW Industrial Facilities Database (TFD) for CONUS. On the
web at: http://www.epa.gov/ost/basins/metadata/ifd.htm.

USEPA, 1999A. BASINS Version 2.0 - Region 10. January, 1999. EPA-823-C-98-012.
USEPA, Office of Water, Washington, D.C.

USEPA, 1999B.  STOrage and RETrieval (STORE!) database. Water Quality report for
Cottonwood Creek watershed, Idaho. Washington, D.C.
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