Milltown Dam Collection, 1906-2007  PDF

Overview of the Collection

Title
Milltown Dam Collection
Dates
1906-2007 (inclusive)
Quantity
19.75 linear feet
Collection Number
Mss 907
Summary
The Milltown Dam was a hydroelectric dam located seven miles east of Missoula, Montana, at the confluence of the Clark Fork River and Blackfoot River near Milltown and Bonner, Montana. This collection contains records from a variety of sources documenting the dam's operation and impact from 1906-2006. The dam was removed in 2008.
Repository
University of Montana, Mansfield Library, Archives and Special Collections
Archives and Special Collections
Maureen and Mike Mansfield Library
University of Montana
32 Campus Dr. #9936
59812-9936
Missoula, MT
Telephone: 406-243-2053
Fax: 406-243-4067
library.archives@umontana.edu
Access Restrictions

Researchers must use collection in accordance with the policies of Archives and Special Collections, the Maureen and Mike Mansfield Library, and The University of Montana-Missoula.

Languages
English


Historical NoteReturn to Top

The Milltown Dam was a hydroelectric dam located seven miles east of Missoula, Montana, at the confluence of the Clark Fork and Blackfoot rivers near Milltown and Bonner, Montana. William A. Clark, a renowned copper mine investor and U.S. Senator, built the dam in 1908, to power his sawmill located in the town of Bonner, Montana before its electrical services were extended to the surrounding communities. In 1929, Montana Power Company purchased the dam from Clark and operated it until 2003, when Northwestern Energy assumed ownership of the dam as part of a collective purchase of Montana Power Company's electric and gas network.

A few months after the dam was built, a flood washed toxic mine waste from the Anaconda Copper Mining Company's work site near Butte, Montana, 126 miles downstream before it settled in the newly formed reservoir behind the Milltown Dam. The severity of the toxic waste accumulation was not realized until 1981, when the Montana Department of Health and Environmental Science conducted its bi-annual water quality study that found high concentrations of arsenic in four residential wells in Milltown, Montana. This led to approximately 120 miles of the Clark Fork River being added to the Environmental Protection Agency's (EPA) National Priorities List (NPL), commonly referred to as a Superfund site, in September of 1983. The Milltown Dam was designated as one of three Operable Units (OU), a distinct area designated within a larger Superfund cleanup site, on the Clark Fork River. Over the next quarter of a century research and investigation into possible methods of containment, remediation, and restoration ensued as part of the most expensive Superfund cleanup operations in United States History at that time costing approximately $100 million.

Following the Milltown Dam's 1983 listing, local, state, and federal resources were focused on the containment of harmful mining waste until 1996, when a severe ice jam on the Blackfoot River scoured the reservoir's toxic sediments leading to increased public safety concerns. As a result, the EPA decided that the complete removal of the dam was the best plan of action. In 2006, contaminated sediments were moved to a disposal site in Opportunity, Montana, and the dam was removed in 2008.

Following the dam's removal, efforts to restore the watershed at the confluence of the Blackfoot and Clark Fork rivers began, and the area was designated as the 500-acre Milltown State Park. The park offers interpretive sites, historical information, and outdoor recreation opportunities. In addition to public access, efforts were made to restore native vegetation in the Clark Fork and Blackfoot river flood plains.

Content DescriptionReturn to Top

The Milltown Dam Collection contains official and unofficial records about the dam and its operation from a variety of record creators. The collection includes reports, pamphlets, receipts, logbooks and photographs of energy output, construction, breakdowns, and maintenance work carried out on the dam. It also includes safety and licensing records required by the Federal Energy Regulatory Commission.

Records in the collection include those created by William A. Clark's affiliated companies between 1908 and 1929, the Montana Power Company, which owned and operated the dam between 1929 and 2003, and Northwestern Energy, which owned and operated the project from 2003 until its shutdown in 2006.

The collection also contains risk assessment and remedial action plan reports that were generated as part of the Superfund cleanup process. This includes reports generated by third party researches, private businesses, and local, state, and federal government agencies. Also included in the collection is a record of public commentary surrounding the Superfund cleanup process. The removal of the dam is documented mainly in audiovisual formats. This includes photographs of the powerhouse shutdown, an audio recording conducted by Missoula County Environmental Health Supervisor Peter Nielson, and video footage created by Missoula Community Access Television. Missoula Community Access television and Montana Power Company videos concerning the dam's history, ice jams, and the cleanup process are also housed in this collection.

Use of the CollectionReturn to Top

Restrictions on Use

Researchers are responsible for using in accordance with 17 U.S.C. and any other applicable statutes. Non-exclusive copyright in a portion of the collection material was transferred to the University of Montana.

Preferred Citation

Milltown Dam Collection, Archives and Special Collections, Maureen and Mike Mansfield Library, University of Montana-Missoula.

Administrative InformationReturn to Top


Detailed Description of the CollectionReturn to Top

Series I:  Drawings and Prints, 1906-1998Return to Top

0.5 linear feet

This series contains large drawings and prints used in construction and maintenance projects. These materials were created and stored by the owners and operators of the Milltown Dam. At times related materials are grouped together in this series, but because specialized knowledge is required to accurately organize the materials in this series, the prints and drawings have been left in their original order. A drawing number key, located in box two folder one of this series, corresponds with most of the early drawings in this series up through the 1930s. Later drawings possess similar numerical identifiers, but the University of Montana Archives and Special Collections does not have the corresponding key.

Series I contains materials from accession 2010-007. The content was picked up at the Milltown Dam site by Archives staff. It has been listed largely at the item level. Materials originally housed together were divided into separate folders for preservation purposes and to increase accessibility, but otherwise have been maintained in the order in which they were received. The contents of folder 8 were individually rolled drawings and prints that were originally housed together in a single folder.
Container(s) Description Dates
Box/Folder
2/1
Drawing Number Key for Series I: Drawings and Prints, 1906-1998
Undated
drawer-folder
VIII-9/1
Scraps from Montana Power Company Drawings
1988
VIII-9/1
Plan for Power House
1906
VIII-9/1
Power House Sections and Floor Plans
1907
VIII-9/1
Wiring Diagram
1907
VIII-9/1
Conduit Wiring
1907
VIII-9/1
Toe of Dam
1909
VIII-9/1
Power House
1908
VIII-9/2
Bearing Details for Countershaft, Penstock Gates
1912
VIII-9/2
Sluice Gate for Dam
1906
VIII-9/2
Floor Plan Showing Reinforcements
1907
VIII-9/2
Flashboard Detail
1911
VIII-9/2
Flashboard Detail
1911
VIII-9/2
Penstock Gates for Exciter Turbines
1907
VIII-9/2
Steel Plate for Corners of Fore-bay Floor
1907
VIII-9/2
Emergency Flume Spillway
1909
VIII-9/2
Proposed Construction of South Abutment
1909
VIII-9/2
Exciter at Bonner Power House
Undated
VIII-9/2
Flashboard Detail
1917
VIII-9/2
2 Inch Pine Segments for Concrete Forms Against Turbine
1907
VIII-9/2
Segments for Concrete Arches
1906
VIII-9/2
2 Inch Pine Segments for Concrete Forms Against Turbine
Undated
VIII-9/2
Thimble in Concrete Wall
1907
VIII-9/2
Upstream Wall of Power House
Undated
VIII-9/2
Control Switches and Solenoid on 11000 Volt Line
1913
VIII-9/2
24 inch Crib Showing Steps
Undated
VIII-9/2
Floor Beams and Reinforcement Bars
1907
VIII-9/2
Downstream Toe of Dam
1908
VIII-9/3
Sounding at Toe of Dam
1976
VIII-9/3
Section of Power House
Undated
VIII-9/3
Proposed Modifications of Dam and Power Plant
1907
VIII-9/4
Clipping from a Drawing of Unit #7
Undated
VIII-9/4
Conduit Wiring
1907
VIII-9/4
Plan for Power House
1908
VIII-9/4
Drawing No. 8
1906
VIII-9/4
Elbow Attached to Thimble to be Used for Draining Pond
1907
VIII-9/4
Section Through Spillway at Break Showing Proposed Method of Reconstruction
1908
VIII-9/4
Wiring Diagram of Generating Station
Undated
VIII-9/4
Comparison of Bids for Equipment of Power House
1906
VIII-9/4
Elevations Along Breakwater
1914
VIII-9/4
Stability Diagram to Accompany Plan No. 2 for Reconstruction Work
1907
VIII-9/4
Stability Diagram of Concrete Wall Forming Upstream Side of Power House
1907
VIII-9/4
Forms and Tremie
1930
VIII-9/4
East End Power House
1907
VIII-9/4
Down Stream Elevation of Power House
1908
VIII-9/4
General Plan of Power House Walls
1907
VIII-9/4
Clark's Dam
1906
VIII-9/4
Penstock Gates for Power House
1907
VIII-9/4
Stability Diagram to Accompany Plan No. 2 for Reconstruction Work
1907
VIII-9/4
Sketch of New Breakwater Wall and Toe Reinforcement
1930
VIII-9/4
Penstock Gate
1958
VIII-9/4
Gate Slides and Seals for Penstock Tubes
1906
VIII-9/4
Drawing No. 42
Undated
VIII-9/5
Downstream Elevation of Power House
1908
VIII-9/5
Proposed Reconstruction
1908
VIII-9/5
Plan and Elevation Views
1965
VIII-9/5
Soundings
1930
VIII-9/5
Soundings
1929
VIII-9/5
Sluice pipes for Draining Dam
1907
VIII-9/5
Clark's Dam
1906
VIII-9/5
Reconstruction of Downstream Toe of Dam
1909
VIII-9/5
Abutment Wall Elevation and Cross Sections
1965
VIII-9/5
Steel Details for Penstock Gate
1958
VIII-9/5
Flashboard Detail
1911
VIII-9/5
Penstock Gate for Exciter Turbines
1959
VIII-9/5
End View Water Wheels of Exciter Unit
1909
VIII-9/5
Penstock Gate for Exciter Turbines
1907
VIII-9/5
Sketch Showing Improvements to be Made
1908
VIII-9/5
Proposed Concrete and Steel Plate Fillet for Fore-bay
1907
VIII-9/5
Wing Cribs Upstream Side of Dam and on Sides of Fore-bay
1907
VIII-9/5
General Scheme of Reconstruction
1909
VIII-9/5
Abutment Wall-Clark's Dam as Constructed
1930
VIII-9/5
Construction at Toe Dam
1931
VIII-9/5
Cut-off Wall Clark's Dam North Side Fore-bay
1931
VIII-9/5
Cross Sections Abutment Wall
1931
VIII-9/6
Tail Race Walls and Reconstruction South End
1931
VIII-9/6
Sketch Showing Rock Pile to be Removed from Clark's Dam
Undated
VIII-9/6
Sounding Clark's Dam Elevations and Toe
1930
VIII-9/6
Section through Gap at South End of Dam
1909
VIII-9/6
Section Through Roof Showing Lumber and Ruberoid Required
1907
VIII-9/6
Details of Brick Work
1907
VIII-9/6
Sections of Milltown (Clark) Dam
1938
VIII-9/6
Summation Quantities
1930
VIII-9/6
Details of Grid Bars and Scheme of Holding Them Together
1906
VIII-9/6
Concrete Wall from Upstream Side of Power House
1906
VIII-9/6
Downstream Elevation of Power House Walls
1906
VIII-9/6
Section Through Power House
1908
VIII-9/6
Supplement to Conduit Drawing No.1
1907
VIII-9/6
Conduits in Power House
1912
VIII-9/6
Grid Bar Supports
1906
VIII-9/6
West End Elevation of Power House
1906
VIII-9/6
Crest of Spillway
Undated
VIII-9/6
Field Modification to 230-D-45 Tower
1976
VIII-9/6
Detail of Stem Guide and Bracket
Undated
VIII-9/6
Unlabeled Drawing
Undated
VIII-9/6
Exit Stem for 9x14 Sluice Gate
Undated
VIII-9/6
Stability Diagram of Proposed Concreate Wall for Upstream Side of Power House
1907
VIII-9/7
Arrangement of Entrance Panels
1907
VIII-9/7
Busbar Compartment at H.T. Wiring
1907
VIII-9/7
Wooden Segments for Circular Openings Through Concrete Wall Segments
1906
VIII-9/7
Stability Diagram of Concrete Wall Upstream Side of Break in Dam
1908
VIII-9/7
Elevation of Points on Top of Breakwater to Determine Settlement and Soundings in Cribs
1909
VIII-9/7
Steel Details Penstock Gate for Exciter Turbines
1959
VIII-9/7
Gate Hoist Frame
1957
VIII-9/7
Operating Mechanism Gate 7 and 8
1912
VIII-9/7
Penstock Gates
1907
VIII-9/7
Wiring Diagram of Generating Station
1907
VIII-9/7
Downsteram Elevation of Power House
1908
VIII-9/7
Design of Cribwork Toe of Dam
1909
VIII-9/7
Gate Hoist Instalation
1957
VIII-9/7
Gate with Steel Frame Attached for Lifting with Hydraulic Jack
1906
VIII-9/7
Detail of Form for Toe Reinforcing
1925
VIII-9/7
Roof Plan of Power House
1911
VIII-9/7
Pockets to be Cut in Concrete Wall for Steel Brace
1907
VIII-9/7
Arrangement of Transformers and Wiring
1907
VIII-9/7
Flashboard Detail
1911
VIII-9/7
Flashboard Detail
1917
VIII-9/7
Transformers and Busbar Compartments and Wiring
1907
VIII-9/7
Diagram of Switchboard Wiring in Power House
1907
VIII-9/7
Windows for Monitor of Power house
1907
VIII-9/8
Project Boundry
1989
VIII-9/8
General Plan of Dam and Plant
Undated
VIII-9/8
Toe Sounding
1975
VIII-9/8
Rehabilitation Power House
Undated
VIII-9/8
Milltown Plant Power Wiring Diagrams
1953
VIII-9/9
Spillway Repair
4 drawings
1983
VIII-10/10
Dif Metering
4 drawings
1975
VIII-10/11
One Line Diagram
3 drawings
1998
VIII-10/12
Spillway Repair
16 drawings
1983
VIII-10/13
Spillway Light, Project Area, Dividing Block Fore-bay
35 drawings
Undated
VIII-10/14
Sluceway Structure Intake Gates and Trash Rack
11 drawings
Undated
VIII-10/15
Exhibit L License Application
6 Drawings
Undated
VIII-10/16
Rehabilitation Prints
8 drawings
Undated
VIII-10/17
Milltown Project
9 drawings
Undated
VIII-10/18
Rehabilitation
56 drawings
1985

Series II:  Reports and Logbooks, 1929-2005Return to Top

9.75 linear feet

This series contains reports, records, and logs of the Milltown Dam's operations created and stored by the owners and operators of the Milltown Dam, and it is divided into six sub-series. These materials contain information on the dams energy output, weather conditions, water levels and flows, and general operation notes.

Each sub series is arranged chronologically reflecting original order. Duplicated reports and logs were removed in processing. Series II is divided into six sub-series processed at the folder. All of the sub-series contain materials from accession 2010-007 and are arranged chronologically.
Container(s) Description Dates
Sub-series 1: Daily Reports and Logs
8.0 linear feet
This sub-series contains records of A.C. amps, D.C. amps, and Kilowatt output for the dam’s five generators and two exciters as well as records of water flow, reservoir elevation, and weather recorded daily.
Contents are arranged chronologically.
1951-2002
Box
OS 1
Daily Report
July 21- August 16, 1951
OS 1
Daily Report
April 20-June 19, 1952
OS 1
Daily Report
March 23-June 30, 1953
OS 1
Daily Report
July 1-September 29, 1953
OS 1
Daily Report
September 30-December 31, 1953
OS 1
Daily Report
January-April, 1954
OS 1
Daily Report
May-December, 1954
2
Daily Report
January, 1983
2
Daily Report
February, 1983
2
Daily Report
March, 1983
2
Daily Report
April, 1983
2
Daily Report
May, 1983
2
Daily Report
June, 1983
2
Daily Report
July, 1983
2
Daily Report
August, 1983
2
Daily Report
September, 1983
2
Daily Report
October, 1983
2
Daily Report
November, 1983
2
Daily Report
December, 1983
3
Daily Report
January, 1986
3
Daily Report
February, 1986
3
Daily Report
March, 1986
3
Daily Report
April, 1986
3
Daily Report
May, 1986
3
Daily Report
June, 1986
3
Daily Report
July, 1986
3
Daily Report
August, 1986
3
Daily Report
September, 1986
3
Daily Report
October, 1986
3
Daily Report
November, 1986
3
Daily Report
December, 1986
3
Daily Report
Undated
4
Daily Report
May-August, 1987
4
Daily Report
September-December, 1987
4
Daily Report
January-April, 1988
4
Daily Report
May-August, 1988
5
Daily Report
September-December, 1988
5
Daily Report
January-April, 1989
5
Daily Report
May-August, 1989
5
Daily Report
September-December, 1989
6
Daily Report
January-April, 1990
6
Daily Report
May-August, 1990
6
Daily Report
September-December, 1990
6
Daily Report
January-April, 1991
7
Daily Report
May-August, 1991
7
Daily Report
September-December, 1991
7
Daily Report
January-April, 1992
7
Daily Report
May-August, 1992
8
Daily Report
September-December, 1992
8
Daily Report
January-April 1993
8
Daily Report
May-August, 1993
8
Daily Report
September-December, 1993
9
Daily Report
January-April, 1994
9
Daily Report
May-August, 1994
9
Daily Report
September-December, 1994
9
Daily Report
January-April, 1995
10
Daily Report
May-August, 1995
10
Daily Report
September-December, 1995
10
Daily Report
January-April, 1996
10
Daily Report
May-August, 1996
11
Daily Report
September-December, 1996
11
Daily Report
January-April, 1997
11
Daily Report
May-August, 1997
11
Daily Report
September-December, 1997
12
Daily Report
January-March, 1998
12
Daily Report
April-June, 1998
12
Daily Report
July-September, 1998
12
Daily Report
October-December, 1998
13
Daily Report
January-March, 1999
13
Daily Report
April-June, 1999
13
Daily Report
July-September, 1999
13
Daily Report
October-December, 1999
13
Daily Report
January-March, 2000
14
Daily Report
April-June, 2000
14
Daily Report
July-September, 2000
14
Daily Report
October-December, 2000
14
Daily Report
January-March, 2001
14
Daily Report
April-June, 2001
15
Daily Report
July-September, 2001
15
Daily Report
October-December, 2001
15
Daily Report
January-March, 2002
15
Daily Report
April-June, 2002
15
Daily Report
July-September, 2002
16
Daily Report
October-December, 2002
16
Daily Report
January-April, 2003
16
Daily Report
May-August, 2003
16
Daily Report
September-December, 2003
17
Daily Report
January-April, 2004
17
Daily Report
May-August, 2004
17
Daily Report
September-December, 2004
17
Daily Report
January-April, 2005
17
Daily Report
May-August, 2005
17
Daily Report
September-December, 2005
17
Daily Report
January-April, 2006
18
Daily Report
May-August, 2006
18
Daily Report
September-December, 2006
18
Daily Report
January-April, 2007
18
Daily Report
May-August, 2007
18
Daily Report
September-December, 2007
18
Daily Report
January-February, 2008
19
Milltown Plant Daily Log Book
July 27, 1995-October 1, 1999
19
Milltown Plant Daily Log Book
October 2, 1999-November 10, 2000
19
Milltown Plant Daily Log Book
November 11, 2000-May 14, 2002
Sub-series 2: Monthly Reports and Logs
1.0 linear feet
This sub-series contains records of temperature, water data, meter readings, and generation data.
Contents are arranged chronologically.
1945-2005
Box
OS 20
Weather, Water, and Electrical Record Book
November 1929-May 1945
OS 20
Weather, Water, and Electrical Record Book
June 1945-June 1997
OS 21
Monthly Log
1955-1959
OS 21
Monthly Log
1960-1963
OS 21
Monthly Log
1964-1967
OS 21
Monthly Log
1968-1971
OS 21
Monthly Log
1972-1975
OS 21
Monthly Log
1976-1979
22
Monthly Log
1980
22
Monthly Log
1981
22
Monthly Log
1982
22
Monthly Log
1983
22
Monthly Log
1984
22
Monthly Log
1985
22
Monthly Log
1986
22
Monthly Log
1987
22
Monthly Log
1988
22
Monthly Log
1989
22
Monthly Log
1990
22
Monthly Log
1991
22
Monthly Log
1992
22
Monthly Log
1993
22
Monthly Log
1994
22
Monthly Log
1995
22
Monthly Log
1996
22
Monthly Log
1997
22
Monthly Log
1998
22
Monthly Log
1999
22
Monthly Log
2000
22
Monthly Log
2001
23
Monthly Log
2002
23
Monthly Summary of Daily Readings
2003
23
Monthly Summary of Daily Readings
2004
23
Monthly Summary of Daily Readings
2005
Sub-series 3: Hourly Logs
0.25 linear feet
This sub-series consists of eight handwritten logbooks of data collected hourly. The contents are not clearly labeled.
Contents are arranged chronologically.
1978-1986
Box
23
Hourly Log Book
1978-1979
23
Hourly Log Book
1980-1981
23
Hourly Log Book
1981-1982
23
Hourly Log Book
1983
23
Hourly Log Book
1984
23
Hourly Log Book
1985
23
Hourly Log Book
1986
23
Hourly Log Book
undated
Sub-series 4: Monthly Generation Reports
0.25 linear feet
This sub-series contains monthly reports of water data, operation data, and total energy generated by the Milltown Dam. It also provides information about plant shutdowns and the daily average load measured in Kilowatts.
Contents are arranged chronologically.
1972-2002
Box
23
Monthly Generation Reports
1972-1979
23
Monthly Generation Reports
1980-1989
23
Monthly Generation Reports
1990-1999
24
Monthly Generation Reports
2000-2005
24
Miscellaneous Monthly Generation Reports
1992-2002
Sub-series 5: Generator Outage Reports
0.25 linear feet
This sub-series contains log sheets showing the time, date, and cause of generator shutdowns.
Contents are arranged chronologically.
1977-2005
Box
24
Generator Outage Report
1970s
24
Generator Outage Report
1980s
24
Generator Outage Report
1990s
24
Generator Outage Report
2000s
24
Generator Outage Report
undated
Sub-series 6: Monthly Storage Battery Reports
0.1 linear feet
This sub-series contains data sheets showing storage battery volts and amps collected monthly.
Contents are arranged chronologically.
1987-2002
Box
24
Monthly Storage Battery Report
1987-1989
24
Monthly Storage Battery Report
1990-1999
24
Monthly Storage Battery Report
2000-2002

Series III:  Parts Information and Maintenance Records, 1929-1998Return to Top

2.75 linear feet

This series contains drawings, prints, receipts, reports and logs related to maintenance, upkeep, and construction on the Milltown Dam. The owners and operators of the Milltown Dam generated and stored these records.

Materials are arranged alphabetically, which reflects the original order of these records. Photographs were removed and incorporated into Series VI, Sub series I: Milltown Dam Photographs. Series III contains materials from accession 2010-007 and is arranged alphabetically reflecting original order.
Container(s) Description Dates
Box/Folder
24 / 11
Alignment Survey Data Report
1994
25 / 1
Annunciator Prints
1968
25 / 2
Ballast Wiring Shop
Undated
25 / 3
Battery Information
1987-1988 and Undated
25 / 4
Bearings
1971, 1977, 1981 and Undated
25 / 5
Bearing #1
1966-1967 and 1970-1971
25 / 6
Bearing #2
1972-1973
25 / 7
Bearings #2-5
1971-1972
25 / 8
Boat Restraints
1995 and undated
25 / 9
Brushes
1962, 1965, 1995 and 2000
25 / 10
Camp Well
Undated
25 / 11
Commutator and Slip Ring Information
Undated
25 / 12
Commutator and Slip Ring Maintenance Handbook
1949
25 / 13
Dam Reconstruction Information
1984-1985
25 / 14
Differential Relays
1953 and Undated
25 / 15
Diving Inspection
1983
25 / 16
Drains Information
1983 and Undated
25 / 17
Exciter Bearings
1963, 1982, 1991 and Undated
25 / 18
Exciter Bearing Transparency
Undated
26 / 1
Exciter Information
1906, 1941 and 1957
26 / 2
Exciter #1 Reconditioning
1974
26 / 3
Exhaust Fan Information
1988 and 1990
26 / 4
Federal Energy Regulatory Commission Inspections
1980, 1993 and 2003
26 / 5
Federal Energy Regulatory Commission Licensing
1968-2000
26 / 6
Federal Energy Regulatory Commission Monitoring Data
1984
26 / 7
Federal Energy Regulatory Commission Security Checklist
2002
26 / 8
Field Switch Information
Undated
26 / 9
Fisheries Mitigation Annual Report
2000
26 / 10
Fixed Wheel Prints
1986
26 / 11
Generation Power Factor
1969 and undated
26 / 12
Generator Controls and Relays
Undated
26 / 13
Generator Schematic, Alarm Panel, and Exciter Panel Layout and Wiring Diagrams
1953 and 1975
26 / 14
Governor Information (1 of 2)
1951, 1955, 1957, 1960 and 1962
26 / 15
Governor Information (2 of 2)
1951, 1955, 1957, 1960 and 1962
26 / 16
Governor Wiring #4
Undated
26 / 17
Gravity Wall Seepage Report
1997
26 / 18
High Water Information
1972
26 / 19
High Water Information
1974
26 / 20
High Water Information
1981
27 / 1
High Water News Reports
1975
27 / 2
High Water Stream Flow Data
1997
27 / 3
Insurance Map of Milltown
Undated
27 / 4
Leads and Field Reconductoring
Undated
27 / 5
Lights Overhead
Undated
27 / 6
Maintenance Annual Reports
1993-2002
27 / 7
Maintenance Major Rehabilitation
1980
27 / 8
Maintenance Schedules
1979-1980 and 1982
27 / 9
Miscellaneous Notes
1971
27 / 10
Monitoring Log and photographs
2000
27 / 11
Panel Hoist Inspection
1994
27 / 12
Panel Hoist Prints
Undated
27 / 13
Panel Layout Prints
1975
27 / 14
Penstock Gate Prints
1957 and 1959
27 / 15
Penstock Monitoring Program and Logs
1997-2006
27 / 16
Plant Wiring Diagrams
1953 and 1975
27 / 17
Plugging Switches
Undated
27 / 18
Pond Elevation Alarm
Undated
27 / 19
Pond Level Transducer
Undated
28 / 1
Project Maps
Undated
28 / 2
Project 2188 Exhibits F and G
1992
28 / 3
Pump Information
Undated
28 / 4
Radial Gate
1989, 1998, 2003-2004 and Undated
28 / 5
Recloser
1975 and Undated
28 / 6
Recreation Reports and Information
1975 and 1987-1989
28 / 7
Regulator Instructions and Prints
Undated
28 / 8
Rehabilitation Phase II Request for Proposals
1988
28 / 9
Rehabilitation Proposal Drawings
1985
28 / 10
Relay Monitoring
Undated
29 / 1
Reservoir Drawdowns
1980
29 / 2
Reservoir Drawdowns
1981
29 / 3
Reservoir Drawdowns
1984
29 / 4
Reservoir Drawdowns
1985
29 / 5
Reservoir Drawdowns
1989
29 / 6
Reservoir Drawdowns
2001
29 / 7
Reservoir Drawdowns
2002
29 / 8
Reservoir Drawdowns
2003
29 / 9
Reservoir Drawdowns
2004
29 / 10
Reservoir Drawdowns
2005
29 / 11
Reservoir Drawdown Requirements
Undated
29 / 12
Screen Rake Hoist Inspection and Information
1994-1998
29 / 13
Sign Inventory
1995-2006
29 / 14
Silt Accumulation Chart
1979
29 / 15
Solid State Voltage Regulator
1980
29 / 16
Sounding and Leakage Tests
1977 and 1983
29 / 17
Spillway and Dividing Blocks Evaluation Graphs
1973-1982
29 / 18
Spillway Bridge Prints
1996
29 / 19
Spillway Emergency Repairs
1986
29 / 20
Spillway Gate Operation Certificate
1996, 2000-2007
30 / 1
Spillway Leveling Prints
1980
30 / 2
Spillway Rehabilitation General Construction Request for Proposals
1986
30 / 3
Tailrace Efficiency Curve
Undated
30 / 4
Thermal Gun Readings
1998
30 / 5
Toe Sounding
1981
30 / 6
Toe Sounding Charts and Memorandum
1975 and 1977
30 / 7
Training Wall Prints
1973
30 / 8
Transformers
Undated
30 / 9
Trash Boom
1971-1972
30 / 10
Turbine Alignment
1980-1981
30 / 11
Turbine Bearings
1970
30 / 12
Turbine Gate Control Schematic
1969
30 / 13
Turbines, Miscellaneous
Undated
30 / 14
Turbine Water Wheel Specifications and Proposal
1927
30 / 15
Turbines # 3 and 4
1954
30 / 16
Turbine # 5
1972
30 / 17
Water Safety Boom
1970 and 1972
30 / 18
Water Supply Outlook for Montana
1975
30 / 19
Water Wheels, Turbines, and Generator Cost Sheet
1937
30 / 20
Water Utilization Factor
1996-2002
30 / 21
12.5kv Feeder Circuit Map for Missoula, Montana
Undated

Series IV:  Dam Safety Records, 1972-2006Return to Top

2.0 linear feet

This series contains reports and emergency procedure documents from the Milltown Dam related to Federal Energy Regulatory Commission (FERC) standards. This includes documents from both the Montana Power Company and Northwestern Energy. In this series, the Milltown Dam is also referred to as the Milltown Hydroelectric Project and the FERC Project #2543.

Series IV contains materials from accessions 2012-050 and 2014-054, and is arranged chronologically. Materials housed in binders were rehoused in acid free folders during processing.
Container(s) Description Dates
Box/Folder
31 / 1
Dam Safety Investigations
1972
31 / 2
Water Resource and Hazard Planning Report for the Clark Fork River Valley above Missoula
1974
31 / 3
Milltown Hydroelectric Project Engineering Evaluation
1984
31 / 4
Inspection of Project Works
1991
32 / 1
Draft Safety Analysis Report
1995
32 / 2
Community Action Plan for the Bonner Area Communities
1996
32 / 3
Inspection of Project Works
1996
32 / 4
Overtopping Evaluation
2000
32 / 5
Ice Jam Evaluation
2000
32 / 6
Alignment Survey Data Report
2000
33 / 1
Alignment Survey Data Report
2001
33 / 2
Spillway Leakage Evaluation
2001
33 / 3
Missoula County Public Opinion survey Regarding the Milltown Superfund Site
2001
33 / 4
Inspection of Project Works (1 of 3)
2001
33 / 5
Inspection of Project Works (2 of 3)
2001
33 / 6
Inspection of Project Works (3 of 3)
2001
33 / 7
Inspection of Project Works Appendix D (1 of 4)
2001
33 / 8
Inspection of Project Works Appendix D (2 of 4)
2001
34 / 1
Inspection of Project Works Appendix D (3 of 4)
2001
34 / 2
Inspection of Project Works Appendix D (4 of 4)
2001
34 / 3
Inspection of Project Works Appendix E (1 of 2)
2001
34 / 4
Inspection of Project Works Appendix E (2 of 2)
2001
34 / 5
Drilling Contract bid documents and geophysical testing proposal
2002
34 / 6
Inspection of Right Bank Seepage Conditions
2002
34 / 7
Emergency Action Plan
2003
34 / 8
Alignment Survey Data Report
2003
34 / 9
Dam Foundation Exploration Addendum 1 to 2001 Inspection Project Works
2003
35 / 1
Addendum 2 to 2001 Inspection of Project Works
2004
35 / 2
Alignment Survey Data Report
2004
35 / 3
Alignment Survey Data Report
2005
35 / 4
Alignment Survey Data Report
2006
35 / 5
Energency Action Plan Updated Replacement
2006
35 / 6
Emergency Action Plan
Undated

Series V:  Environmental Protection Agency Superfund Cleanup Materials, 1970-2005Return to Top

3.75 linear feet

This series contains research materials and reports related to the Milltown Dam's NPL status and the Superfund cleanup process. The documents were collected by Peter Nielson, Environmental Health Supervisor for Missoula County, Montana, from 1992 to 2018.

Materials were rehoused and placed into acid free folders during processing, but were left in the order in which they were received by the Archives. However the last folder in this series, titled "Save Our Bridge Campaign," contains materials related to the efforts of Bonner and Milltown residents to protect a walking bridge that was scheduled for removal in 2006. This is indirectly related to the Milltown Dam Superfund cleanup process and as a result was placed by the processor at the end of the series. Series V houses materials from accession 2014-054 and is processed at the folder level.
Container(s) Description Dates
Box/Folder
36 / 1
Cultural Resource Report
1990
36 / 2
Sediments Investigations Sampling and Analysis Plan
1989
36 / 3
Continued Releases Risk Assessment
1994
36 / 4
Exposure Survey Plan
1990
36 / 5
Application for Amendment of License Milltown Supplemental Data Supporting Design Report
1985
36 / 6
Inflatable Rubber Dam Retrofit Preliminary Engineering Report
2001
36 / 7
Milltown Dam Conceptual Channel Design Report
2001
36 / 8
Revised Final Draft Focused Feasibility Study
2001
37 / 1
Two Rivers Maps
Undated
37 / 2
Milltown Feasibility Study (1 of 3)
2001
37 / 3
Milltown Feasibility Study (2 of 3)
2001
37 / 4
Milltown Feasibility Study (3 of 3)
2001
37 / 5
Milltown Focused Feasibility Study (1 of 3)
2001
37 / 6
Milltown Focused Feasibility Study (2 of 3)
2001
37 / 7
Milltown Focused Feasibility Study (3 of 3)
2001
37 / 8
Milltown Focused Feasibility Study Comments (1 of 3)
1999-2001
38 / 1
Milltown Focused Feasibility Study Comments (2 of 3)
1999-2001
38 / 2
Milltown Focused Feasibility Study Comments (3 of 3)
1999-2001
38 / 3
Milltown Combined Feasibility Comments (1 of 2)
2001-2002
38 / 4
Milltown Combined Feasibility Comments (2 of 2)
2001-2002
38 / 5
Milltown Dam Federal Energy Regulatory Commission License Surrender
2005
38 / 6
Milltown Memorandum of Understanding
Undated
38 / 7
Public Service Commission (1 of 2)
1998-2002
39 / 1
Public Service Commission (2 of 2)
1998-2002
39 / 2
Milltown Superfund General Background
1982-1995
39 / 3
Risk Assessment Correspondence (1 of 2)
1970-2001
39 / 4
Risk Assessment Correspondence (2 of 2)
1970-2001
39 / 5
Milltown Federal Energy Regulatory Commission Relicensing (1 of 4)
1987 and 2000-2005
39 / 6
Milltown Federal Energy Regulatory Commission Relicensing (2 of 4)
1987 and 2000-2005
40 / 1
Milltown Federal Energy Regulatory Commission Relicensing (3 of 4)
1987 and 2000-2005
40 / 2
Milltown Federal Energy Regulatory Commission Relicensing (4 of 4)
1987 and 2000-2005
40 / 3
Environmental Protection Agency, Remedial Action Master Plan Draft
1983
40 / 4
Assessment of Damages to Anglers and other Recreators from Injuries to the Upper Clark Fork River Basin
1993
40 / 5
Draft Final Screening of Alternatives Summary Report
1995
40 / 6
Draft Addendum to the Draft Final Screening of Alternatives Summary Report
1995
40 / 7
Addendum to the Draft Final Screening of Alternatives Summary Report
1995
41 / 1
Revised Community Relations Plan
1992
41 / 2
Public Health Evaluation Work Plan, Base Line Risk Assessment
1992
41 / 3
Proposed Plan for Interim Institutional Controls
1992
41 / 4
Milltown Air Quality Monitoring Program Draft Report, Volume I
1992
41 / 5
Milltown Air Quality Monitoring Program Draft Report, Volume II
1992
41 / 6
Milltown Air Quality Monitoring Program Draft Report, Volume III
1992
41 / 7
Institutional Controls Workshop
1992
41 / 8
Public Health Evaluation Exposure Survey Results Draft
1991
41 / 9
Endangerment Assessment Work Plan
1990
41 / 10
Data Management Plan
1990
42 / 1
Sediments Investigations Sampling and Analysis Plan
1990
42 / 2
Health and Safety Plan and Site Management Plan
1990
42 / 3
Quality Assurance Project Plan
1990
42 / 4
Discussion Points Wetland Work Plan
1990
42 / 5
Draft Work Plan Continued Releases Risk Assessment
1990
42 / 6
Sampling Program at Milltown and Bonner Junction Program Overview and QA/QC
1990
43 / 1
Work Plan Scoping Document
1989
43 / 2
Technical Comments on CERCLA Documents and Remedial Investigations and Feasibility Studies
1989
43 / 3
Revised Work Plan For Negotiation Support and Oversight
1989
43 / 4
Feasibility Study Work Plan Final Draft
1989
43 / 5
Outline of the Endangerment Assessment Work Plan Draft
1989
43 / 6
Quality Assurance Project Plan
1989
43 / 7
Human Health Evaluation Work Plan Draft
1989
43 / 8
Remedial Investigation Completion and Feasibility Study Work Plan
1989
44 / 1
Cover Letter for Data Summary Report For Milltown Interim Groundwater Monitoring
1998
44 / 2
Clark Fork River Ecological Risk Assessment
1999
44 / 3
Sampling and Analysis Plan
1988
44 / 4
Ecological Risk Assessment Clark Fork River Operable Unit, Volume II
1999
44 / 5
Save Our Bridge Campaign
2006

Series VI:  Photographs, 1907-2007Return to Top

1.0 linear feet

This series is a collection of photographs taken by Milltown Dam affiliates, photographer Kristi Hager, and other unknown photographers. It contains photographs from accessions 2010-007, 2007-019, 2007-020, and 2008-015 and is divided into three sub-series.

The majority of photos are processed at the folder level. Materials in each sub-series are arranged alphabetically by folder title.
Container(s) Description Dates
Sub-series 1: Milltown Dam Photographs
0.75 linear feet
This sub-series contains images collected by the owners and operators of the Milltown Dam from 1907-2003. It includes images of the dam’s construction, maintenance, function, and recreation activities.
Contents are arranged alphabetically by folder title.
1907-2003
Box
VIII-10
Aerial Photographs
Undated
Box/Folder
45 / 1
Dam Construction
Circa 1907
46 / 1
Cement Cutting
1980
46 / 2
Crest of Dam After 17 Board Break
1973
46 / 3
Dam
1997
46 / 4
Dam
1998
46 / 5
Dam Break Pictures
1972
46 / 6
Dam Exterior and Recreation
2003
46 / 7
Dam Inspection
Undated
46 / 8
Dam Flashboard Failure due to Ice and Debris
1986
46 / 9
Dam Interior, Exterior, Reservoir and Maintenance
Undated
46 / 10
Drawdown
2002
46 / 11
Exciter #1 Overhaul
2001
46 / 12
Exciter #2
1996
46 / 13
Exciter #2 Broken Yoke
1980
46 / 14
Exciter #2 Clutch Assembly
1982
46 / 15
High Water
Undated
46 / 16
High Water
1997
46 / 17
High Water and Debris
1975
46 / 18
Ice
Undated
46 / 19
Ice Breakup
1989
46 / 20
Ice Breakup
1996
46 / 21
Plant and Unit #4
1971
46 / 22
Plant Pictures After Interior Paining
1974
46 / 23
Sewer
1968
46 / 24
Sluice Gate, Exciter Gate, and Unlabeled Photographs
1968 and 1970
47 / 1
Spillway Repair
1981
47 / 2
Turning Down #2 Shaft After Buildup
1972
47 / 3
Unit #1 Generator Rewind
1958
47 / 4
Unit #2
1997
47 / 5
Unit #2 Downstream Turbine
Undated
47 / 6
Unit #2 Shaft Buildup at Packing Area
1980
47 / 7
Unit #2 Upstream Bearing
1972
47 / 8
Unit #3 Overhaul
1970
47 / 9
Unit #3 Overhaul
2002
47 / 10
Unit #4 Maintenance
1998
47 / 11
Unit #5 Shaft Turning and Bearing with Cap
1972
47 / 12
Unit #5 Turning Shaft Packing Area for Buildup
1981
47 / 13
Various Pictures including #1 Overhaul
1969
47 / 14
Loose Photos
Undated
Sub-series 2: Kristi Hager Photographs
1 folder (18 photographs and 18 negatives)
This sub-series is a collection of photographs taken by photographer Kristi Hager. It contains six color and twelve black and white photographs of the dam, powerhouse and spillway as well as the photonegatives.
circa 2005
Box/Folder
47 / 15
Dam, Power House, and Spillway
2006
Sub-series 3: Dam and Powerhouse Shutdown
2 CD's
This sub-series contains images from the powerhouse and dam shutdown.
Contents are arranged alphabetically by folder title.
2006
electronic_file
digital images
Milltown Project Final Plant Shutdown
2006
digital images
Milltown Dam Shutdown
2006

Series VII:  Audiovisual Materials, 1997-2006Return to Top

1 CD and 13 DVDs

This series contains audiovisual records concerning the Milltown Dam's history, ice jams, and removal. It includes audio and video recordings created by Missoula Community Access Television, Peter Nielson, Northwestern Energy, and the Montana Power Company. Both digital and physical copies of these materials are available. Series VII contains materials from accessions 2007-020 and 2012-030.

This series is arranged chronologically.
Container(s) Description Dates
drawer
DVD cabinet
Milltown Ice Jam
Moving image on DVD
1996
DVD cabinet
Milltown Dam Ice Flow/Jam Event
Moving image on DVD
1996
DVD cabinet
Milltown Reservoir: An educational Experience
Moving image on DVD
1997
DVD cabinet
EPA Milltown Cleanup Plan
Moving image on DVD
2003
DVD cabinet
Groundwater Pollution in Milltown
Moving image on DVD
2003
DVD cabinet
Milltown Dam Shutdown
Audio recorded by Peter Nielson on CD
April 7, 2006
DVD cabinet
Milltown Dam Construction and Safety
Moving image on DVD
2003
DVD cabinet
Milltown Dam Power Plant Shut Down
Moving image on DVD
April 7, 2006
DVD cabinet
The Confluence of Two Rivers (2 copies)
Moving image on DVD
2006
DVD cabinet
Milltown Dam Power Plant Shut Down (2 copies)
Moving image on DVD
2006
DVD cabinet
Montana Power Company Ice Jam
Moving image on DVD
Undated

Names and SubjectsReturn to Top

  • Subject Terms :
  • Dam failures--Risk assessment
  • Dam retirement--Environmental aspects
  • Environmental policy--Montana--Milltown
  • Hazardous waste site remediation--Montana--Milltown
  • Sediment transport--Clark Fork Watershed (Mont. and Idaho)
  • Geographical Names :
  • Blackfoot River Watershed (Mont.)
  • Clark Fork Watershed (Mont. and Idaho)
  • Milltown (Mont.)--Environmental conditions
  • Milltown Dam (Mont.)
  • Missoula (Mont.)--Politics and government
  • Other Creators :
    • Personal Names :
    • Nielson, Peter (creator)
    • Corporate Names :
    • Missoula Community Access Television (creator)
    • Montana Power Company (creator)
    • Northwestern Energy (creator)
    • United States. Environmental Protection Agency (creator)
    • United States. Federal Energy Regulatory Commission (creator)