U.S. Department of the Interior

U.S. Geological Survey

Scientific Investigations Report 2012–5283

Prepared in cooperation with the Federal Emergency Management Agency

Floods of June 2012 in Northeastern Minnesota
Cover. Left: View of homes flooded by the St. Louis River in the Fond du Lac neighborhood of Duluth, Minnesota, taken from a

helicopter on June 21, 2012 (photograph provided by Walter Leu, Minnesota Department of Transportation).

Top right: An inundation map showing approximate flood-peak extents and depths for June 2012 for the St. Louis River at the

Fond du Lac neighborhood of Duluth, Minnesota (entire map is in appendix 2 of the report). Map prepared by Christiana 

Czuba, U.S. Geological Survey, November 2012. Map base from 2010 National Agricultural Imagery program 

(U.S. Department of Agriculture, 2010). 
Floods of June 2012 in Northeastern 

Minnesota

By Christiana R. Czuba, James D. Fallon, and Erich W. Kessler

Prepared in cooperation with the Federal Emergency Management Agency

Scientific Investigations Report 2012–5283

U.S. Department of the Interior

U.S. Geological Survey
U.S. Department of the Interior

KEN SALAZAR, Secretary

U.S. Geological Survey

Marcia K. McNutt, Director

U.S. Geological Survey, Reston, Virginia: 2012

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Suggested citation:

Czuba, C.R., Fallon, J.D., and Kessler, E.W., 2012, Floods of June 2012 in northeastern Minnesota: U.S. Geological 

Survey Scientific Investigations Report 2012–5283, 42 p. with 3 app.
iii

Contents

Acknowledgments........................................................................................................................................vi

Abstract...........................................................................................................................................................1

Introduction.....................................................................................................................................................1

Purpose and Scope ..............................................................................................................................3

Conditions Leading to the 2012 Floods in Northeastern Minnesota.............................................3

Methods...........................................................................................................................................................6

Computing the Magnitudes of Peak Streamflows...........................................................................6

Estimating Annual Exceedance Probabilities of Peak Streamflows............................................6

Collection of High-Water-Mark Data.................................................................................................6

Flood-Peak Inundation Maps..............................................................................................................8

Flood-Peak Water-Surface Profiles...................................................................................................8

Floods of June 2012 in Northeastern Minnesota......................................................................................9

Magnitudes and Estimated Annual Exceedance Probabilities of Peak Streamflows...............9

Flood-Peak Inundation Maps and Water-Surface Profiles ...........................................................9

Description of Flood Damages and Effects .............................................................................................13

Summary........................................................................................................................................................14

References Cited..........................................................................................................................................14

Glossary.........................................................................................................................................................17

Appendix 1. High-Water-Mark Descriptions...........................................................................................19

Appendix 2. Flood-Peak Inundation Maps...............................................................................................25

Appendix 3. Flood-Peak Water-Surface Profiles....................................................................................39

Figures

1. Map showing locations of study communities in the counties with disaster

declarations in northeastern Minnesota affected by the June 19–20, 2012, flood

events .............................................................................................................................................2

2. Map showing distribution of 2-day rainfall totals for 7 a.m. Central Daylight Time

June 19 through 7 a.m. Central Daylight Time June 21, 2012, and rainfall totals

at selected National Weather Service Cooperative Observing—Fischer Porter

precipitation stations ...................................................................................................................4

3. Graph showing cumulative daily rainfall during June 19–20, 2012, at selected

National Weather Service Cooperative Observing—Fischer Porter precipitation 

stations in northeastern Minnesota ..........................................................................................5

4. Map showing locations of selected U.S. Geological Survey streamgages in the

counties with disaster declarations for the floods of June 2012 in northeastern

Minnesota ......................................................................................................................................7

5. Graph showing provisional stage hydrographs at selected U.S. Geological 

Survey streamgages in northeastern Minnesota for June 10 through 

July 29, 2012.................................................................................................................................12
iv

Tables

1. Provisional total rainfall for June 19–20, 2012, at selected National Weather

Service Cooperative Observing—Fischer Porter precipitation stations in

northeastern Minnesota..............................................................................................................5

2. Provisional flood-peak gage heights, peak streamflows, and annual exceedance

probabilities of peak streamflows during the floods of June 2012 at selected

U.S. Geological Survey streamgages in northeastern Minnesota.....................................10

Appendix 1

1–1. High-water-mark descriptions for the mapped communities of Barnum, Carlton,

Duluth Heights neighborhood in Duluth, Fond du Lac neighborhood in Duluth,

Moose Lake, and Thomson for the floods of June 2012 in northeastern Minnesota......20

1–2. Descriptions of additional high-water marks for the floods of June 2012 in

northeastern Minnesota............................................................................................................22

Appendix 2

2–1. Map showing approximate extent and depth of flood-peak inundation, flood of

June 2012, for the Moose Horn River at Barnum, Minnesota.............................................26

2–2. Map showing approximate extent and depth of flood-peak inundation, flood of

June 2012, for Otter Creek at Carlton, Minnesota .................................................................28

2–3. Map showing approximate extent and depth of flood-peak inundation, flood of 

June 2012, for Miller Creek at the Duluth Heights neighborhood, Duluth, Minnesota....30

2–4. Map showing approximate extent and depth of flood-peak inundation, flood of

June 2012, for the St. Louis River at the Fond du Lac neighborhood, Duluth,

Minnesota ....................................................................................................................................32

2–5. Map showing approximate extent and depth of flood-peak inundation, flood of

June 2012, for the Moose Horn River and Moosehead Lake at Moose Lake,

Minnesota ....................................................................................................................................34

2–6. Map showing approximate extent and depth of flood-peak inundation, flood of

June 2012, for the Thomson Reservoir outflow near the St. Louis River at

Thomson, Minnesota..................................................................................................................36
v

Appendix 3

3–1. Graph showing flood-peak water-surface profile with selected high-water marks

for the Moose Horn River at Barnum, Minnesota, for the flood of June 2012..................40

3–2. Graph showing flood-peak water-surface profile with selected high-water marks

for Otter Creek at Carlton, Minnesota, for the flood of June 2012......................................40

3–3. Graph showing flood-peak water-surface profile with selected high-water marks

for Miller Creek at the Duluth Heights neighborhood, Duluth, Minnesota, for the

flood of June 2012.......................................................................................................................41

3–4. Graph showing flood-peak water-surface profile with selected high-water marks

for the St. Louis River at the Fond du Lac neighborhood, Duluth, Minnesota, for

the flood of June 2012 ................................................................................................................41

3–5. Graph showing flood-peak water-surface profile with selected high-water marks

for the Moose Horn River and Moosehead Lake at Moose Lake, Minnesota, for

the flood of June 2012 ................................................................................................................42

3–6. Graph showing flood-peak water-surface profile with selected high-water marks

for the Thomson Reservoir outflow near the St. Louis River at Thomson,

Minnesota, for the flood of June 2012.....................................................................................42

Conversion Factors and Datums

Inch/Pound to SI

Multiply By To obtain

Length

inch (in.) 2.54 centimeter (cm)

inch (in.) 25.4 millimeter (mm)

foot (ft) 0.3048 meter (m)

mile (mi) 1.609 kilometer (km)

Area

square mile (mi2

) 2.590 square kilometer (km2) 

Flow rate

cubic foot per second (ft3

/s) 0.02832 cubic meter per second (m3/s)

inch per hour (in/h) 0.0254 meter per hour (m/h)

Vertical coordinate information is referenced to the North American Vertical Datum of 1988 

(NAVD 88) or the National Geodetic Vertical Datum of 1929 (NGVD 29).

Horizontal coordinate information is referenced to the North American Datum of 1983 (NAD 83).

Elevation, as used in this report, refers to distance above the vertical datum.

Water year is the 12-month period of October 1 through September 30 designated by the 

calendar year in which it ends.
vi

Abbreviations

AEP annual exceedance probability

CDT Central Daylight Time

CSG crest-stage gage

DEM digital elevation model

FEMA Federal Emergency Management Agency

GIS geographic information system

GPS global positioning system

LiDAR light detection and ranging

MDNR Minnesota Department of Natural Resources

MDPS Minnesota Department of Public Safety

MHSEM Minnesota Homeland Security and Emergency Management

MnDOT Minnesota Department of Transportation

NAVD 88 North American Vertical Datum of 1988 

NGVD 29 National Geodetic Vertical Datum of 1929

NOAA National Oceanic and Atmospheric Administration

NWS National Weather Service

RTK–GPS Real-Time Kinematic Global Positioning System

TIN triangular irregular network

USACE U.S. Army Corps of Engineers

USGS U.S. Geological Survey

WIE weighting of independent estimates

Acknowledgments

The authors would like to thank the National Weather Service, Minnesota Homeland Security 

and Emergency Management, and other member agencies of the Silver Jackets Hazard Mitigation Team for their coordination and assistance during the flood event and the course of this 

study. The city of Duluth and the U.S. Army Corps of Engineers Detroit District and St. Paul 

District are acknowledged for the collection of high-water-mark data that are included in this 

report.

U.S. Geological Survey staff who were instrumental in flood documentation for this study 

include Dan Daly, Erik Lahti, Greg Mitton, Brett Savage, Russ Buesing, Jeff Copa, John Greene, 

Josh Larson, Ben Otto, Eric Wakeman, John Kent, and Kristen Kieta. Chris Ellison and Moon Kim 

are thanked for critical reviews of this report.
Floods of June 2012 in Northeastern Minnesota

By Christiana R. Czuba, James D. Fallon, and Erich W. Kessler

Abstract

During June 19–20, 2012, heavy rainfall, as much as 

10 inches locally reported, caused severe flooding across 

northeastern Minnesota. The floods were exacerbated by wet 

antecedent conditions from a relatively rainy spring, with May 

2012 as one of the wettest Mays on record in Duluth. The 

June 19–20, 2012, rainfall event set new records in Duluth, 

including greatest 2-day precipitation with 7.25 inches of rain. 

The heavy rains fell on three major watersheds: the Mississippi Headwaters; the St. Croix, which drains to the Mississippi River; and Western Lake Superior, which includes 

the St. Louis River and other tributaries to Lake Superior. 

Widespread flash and river flooding that resulted from the 

heavy rainfall caused evacuations of residents, and damages to 

residences, businesses, and infrastructure. In all, nine counties 

in northeastern Minnesota were declared Federal disaster areas 

as a result of the flooding.

Peak-of-record streamflows were recorded at 

13 U.S. Geological Survey streamgages as a result of the 

heavy rainfall. Flood-peak gage heights, peak streamflows, and annual exceedance probabilities were tabulated 

for 35 U.S. Geological Survey streamgages. Flood-peak 

streamflows in June 2012 had annual exceedance probabilities estimated to be less than 0.002 (0.2 percent; recurrence 

interval greater than 500 years) for five streamgages, and 

between 0.002 and 0.01 (1 percent; recurrence interval greater 

than 100 years) for four streamgages. High-water marks were 

identified and tabulated for the most severely affected communities of Barnum (Moose Horn River), Carlton (Otter Creek), 

Duluth Heights neighborhood of Duluth (Miller Creek), Fond 

du Lac neighborhood of Duluth (St. Louis River), Moose 

Lake (Moose Horn River and Moosehead Lake), and Thomson (Thomson Reservoir outflow near the St. Louis River). 

Flood-peak inundation maps and water-surface profiles were 

produced for these six severely affected communities. The 

inundation maps were constructed in a geographic information 

system by combining high-water-mark data with high-resolution digital elevation model data. The flood maps and profiles 

show the extent and depth of flooding through the communities and can be used for flood response and recovery efforts by 

local, county, State, and Federal agencies.

Introduction

Flood information is needed by Federal, State, and local 

agencies to make informed decisions in meeting mission 

requirements related to flood hazard mitigation, planning, and 

response. For example, the Federal Emergency Management 

Agency (FEMA), U.S. Army Corps of Engineers (USACE), 

the National Weather Service (NWS) of the National Atmospheric and Oceanic Administration (NOAA), Minnesota 

Department of Natural Resources (MDNR), Minnesota 

Department of Public Safety (MDPS) and its division of 

Homeland Security and Emergency Management (MHSEM) 

need timely information on the magnitudes and frequency of 

floods to help respond to flood damage, enhance emergency 

response management, protect infrastructure, provide recovery guidance from the National Flood Insurance Program and 

State regulatory programs, and plan for future flood events.

In Minnesota, many of the agencies that need post-flood 

information are members of a State Hazard Mitigation Team 

commonly referred to as Silver Jackets. State Silver Jackets 

chapters are sponsored by the USACE and in Minnesota 

include as charter members, but is not limited to, the following agencies: USACE, FEMA, MDNR, MHSEM, NWS, and 

U.S. Geological Survey (USGS).

Heavy rains on June 19–20, 2012, caused severe flooding in northeastern Minnesota and prompted the NWS to issue 

areal flood, flash-flood, and river flood warnings. The flood 

peaks1 were exacerbated by a relatively rainy spring, including 

one of the wettest Mays on record (Minnesota Department of 

Natural Resources State Climatology Office, 2012a). During 

the flooding in June 2012, evacuations, water rescues, and 

road closures were common in communities affected by the 

flooding. Damages from flooding were extensive and included 

major transportation disruptions and damage to homes and 

businesses, dams and flood-control structures, and parks and 

recreation areas. Damage caused by the flooding resulted in a 

Presidential Disaster Declaration on July 6, 2012, for the nine 

counties in northeastern Minnesota affected by the June 19–20, 

2012, flood events (Federal Emergency Management Agency, 

2012; fig. 1). This disaster declaration also includes a separate storm event in central Minnesota on June 14, 2012, for 

six counties (Federal Emergency Management Agency, 2012; 

1

 Terms in bold type are defined in the Glossary at the back of the report.
2 Floods of June 2012 in Northeastern Minnesota

EXPLANATION

! Study community

Major watershed boundary

Counties with disaster declarations

!! !

!

!

!

Barnum

Thomson

Carlton

Moose Lake

Fond du Lac, Duluth

Duluth Heights, Duluth

Barnum

Thomson

Carlton

Moose Lake

Fond du Lac, Duluth

Duluth Heights, Duluth

AITKIN

PINE

ST. LOUIS

CARLTON

CASS

ITASCA

MILLE LACS

LAKE

KANABEC

CROW 

WING

MORRISON

Kettle R

Mississippi R

Rum River

Cloquet R

Snake River

St. Louis R

Nemadji River

St. Croix River St. Croix River

93°30' 93°00' 92°30' 92°00' 91°30'

47°00'

46°30'

Moose Horn R

Miller Cr

Otter Creek

St. Croix 

watershed

Western Lake 

Superior watershed

Mississippi 

Headwaters 

watershed

Base modified from Minnesota Department of Natural Resources, 1993,

1:24,000 and 1:100,000 and U.S. Geological Survey digital data, 1:200,000 

Universal Transverse Mercator projection, Zone 15

0 10 20 40 MILES

0 10 20 40 KILOMETERS

ST. LOUIS

CASS

LAKE

ITASCA

PINE

AITKIN

COOK

RICE

CROW 

WING

CARLTON

SIBLEY

GOODHUE

MEEKER

KANDIYOHI

DAKOTA

MINNESOTA Study area

LAKE SUPERIOR

WISCONSIN

Map location

Figure 1. Locations of study communities in the counties with disaster declarations in northeastern Minnesota affected by 

the June 19–20, 2012, flood events.
Introduction 3

Minnesota Department of Natural Resources State Climatology Office, 2012b); however, this report focuses only on the 

flooding effects in northeastern Minnesota, including the nine 

contiguous counties of Aitkin, Carlton, Cass, Cook, Crow 

Wing, Itasca, Lake, Pine, and St. Louis (fig. 1).

Given the severity of the June 2012 flooding in northeastern Minnesota, the USGS, in cooperation with FEMA, 

lead a study to document the meteorological and hydrologic 

conditions leading to the flood, and compile flood-peak gage 

heights, streamflows, and annual exceedance probabilities at 

USGS streamgages. The study also provided data to construct 

flood profiles and flood-peak inundation maps. Flood profiles 

and flood-peak inundation maps were constructed for six communities in northeastern Minnesota (fig. 1): Barnum (Moose 

Horn River), Carlton (Otter Creek), Duluth Heights neighborhood of Duluth (Miller Creek), Fond du Lac neighborhood of 

Duluth (St. Louis River), Moose Lake (Moose Horn River and 

Moosehead Lake), and Thomson (Thomson Reservoir outflow 

near the St. Louis River). The USGS and FEMA collaborated 

and consulted with Silver Jackets team members extensively in 

determining locations needing flood documentation.

Purpose and Scope

The purpose of this report is to document the floods 

of June 2012 in northeastern Minnesota. This report documents the magnitude and extent of flooding and the methods 

used to define the extent of flooding. High-water-mark data 

were collected after the flood and used to develop flood-peak 

inundation maps for the six communities most affected by 

the riverine flooding: Barnum (Moose Horn River), Carlton 

(Otter Creek), Duluth Heights neighborhood of Duluth (Miller 

Creek), Fond du Lac neighborhood of Duluth (St. Louis 

River), Moose Lake (Moose Horn River and Moosehead 

Lake), and Thomson (Thomson Reservoir outflow near the 

St. Louis River). The report summarizes meteorological and 

hydrologic conditions leading up to the flood. The severity of 

flooding is put into regional context by computing flood-peak 

magnitudes and annual exceedance probabilities at 35 USGS 

streamgages in the counties in northeastern Minnesota with 

disaster declarations. Flood effects and damages are summarized on the basis of information obtained from FEMA, 

NWS, MDPS, MHSEM, MDNR, Minnesota Department of 

Transportation (MnDOT), local agencies, news accounts, 

photographs, and corroborated testimony from individuals in 

flood-affected communities.

Conditions Leading to the 2012 Floods in 

Northeastern Minnesota

The June 2012 flooding in northeastern Minnesota was 

caused by heavy rainfall on areas that had already received 

above-normal precipitation. For much of northeastern Minnesota, spring and early summer had the highest total rainfall 

levels as compared to historical data for the same months 

(Minnesota Department of Natural Resources State Climatology Office, 2012c). May 2012 was one of the wettest Mays on 

record in some areas of central and northeastern Minnesota, 

and was the sixth wettest May on record for Duluth (Minnesota Department of Natural Resources State Climatology 

Office, 2012a).

In the weeks before the flooding rains of June 19–20, 

2012, the ground was saturated from numerous storm systems 

that delivered 2–4 inches (in.) of rain across parts of northeastern Minnesota. On June 19, 2012, a warm front moved 

in and stalled across northern Minnesota, bringing waves 

of thunderstorms to the area (Graning and Hluchan, 2012). 

The heavy rainfall continued until late June 20, 2012, when 

a cold front moved through the area. Carlton County and 

southern St. Louis County had the highest levels of rainfall, 

and new records were set in Duluth, including greatest 2-day 

precipitation with 7.25 in. falling June 19–20, 2012 (Graning 

and Hluchan, 2012). Local reports of rainfall were as high 

as 8–10 in. throughout Duluth neighborhoods (Graning and 

Hluchan, 2012). This June 2012 flood event was the most 

damaging flood in Duluth’s history, surpassing the August 

1972 flood event (Minnesota Department of Natural Resources 

State Climatology Office, 2012d).

A spatial gridded dataset of estimated rainfall totals 

prepared by the NWS (National Weather Service, written 

commun., 2012) shows rainfall totals of 7 in. and greater 

for June 19–20, 2012, in parts of Carlton County and southern St. Louis County (fig. 2). Total rainfall amounts for six 

NWS Cooperative Observing—Fischer Porter precipitation 

stations in northeastern Minnesota recorded rainfall totals 

ranging from 2.73 in. at Eveleth in St. Louis County to 6.27 

in. at Sandy Lake in Aitkin County for the storm event on 

June 19–20, 2012 (fig. 2; table 1). Local direct measurements 

of rainfall totals may differ from the spatial gridded dataset 

that is developed from radar data. A seventh Cooperative 

Observing—Fischer Porter precipitation station is located 

in Floodwood (not shown) in St. Louis County but was not 

included in this report because the gage was overtopped during the June rainfall and data were lost.

The cumulative 15-minute rainfall data from the six 

NWS Cooperative Observing—Fischer Porter precipitation 

stations (locations shown in fig. 2) indicate the magnitude 

and timing of the rain that fell throughout the storm events on 

June 19–20, 2012 (fig. 3). Instantaneous rainfall intensities 

were as great as 2 to 4 inches per hour (in/h) in the evening of 

June 19, 2012.

The heavy rains fell on three major watersheds: the Mississippi Headwaters; the St. Croix, which drains to the Mississippi River; and Western Lake Superior, which includes the 

St. Louis River and other tributaries to Lake Superior (fig. 2). 

Along the northern shore of Lake Superior, flash flooding was 

exacerbated by impervious soils and bedrock, and by the steep 

gradients of streams that drain directly to Lake Superior. In 

other areas receiving the heavy rainfall, storage from lakes and 

wetlands delayed and reduced the flood peaks but still resulted 

in record or near-record floods.
4 Floods of June 2012 in Northeastern Minnesota

0

Trace

> 0.001

>0.01

> 0.20

> 0.40

> 0.60

> 0.80

> 1.00> 1.50

> 2.00> 2.50

> 3.00> 3.50

> 4.00

> 5.00

> 6.00

> 7.00

> 8.00

Major watershed boundary

94° 93° 92° 91° 90°

48°

47°

46°

X

X X

X

X

X

!! !

!

!

!

Wales

5.28

Pokegama

4.3

Eveleth

2.73

Holyoke

4.72

Gull Lake

2.84

Sandy Lake

6.27

Wales

5.28

Pokegama

4.3

Eveleth

2.73

Holyoke

4.72

Gull Lake

2.84

Sandy Lake

6.27

Barnum

Thomson

Carlton

Moose Lake

Fond du Lac, Duluth

Duluth Heights, Duluth

Barnum

Thomson

Carlton

Moose Lake

Fond du Lac, Duluth

Duluth Heights, Duluth

ST. LOUIS

CASS

LAKE

ITASCA

PINE

AITKIN

COOK

KOOCHICHING

BELTRAMI

MORRISON

CROW 

WING

CARLTON

TODD

BENTON

STEARNS

ISANTI

MILLE LACS

KANABEC

HUBBARD

LAKE OF 

THE WOODS WADENA

CHISAGO

Snake R

Rainy River

Kettle River

Cloquet River

Big Fork R

Little Fork R

Pine River

Mississippi River

Rum River

Red Lake R

Rapid River

St. Louis R

St. Croix River

Vermilion R

Crow Wing R

Nemadji R

Leech Lake R

St. Croix 

watershed

Western Lake 

Superior watershed

Mississippi 

Headwaters 

watershed

EXPLANATION

! Study community

National Weather Service Cooperative Observing—Fischer 

Porter precipitation station—Rainfall total, in inches

MINNESOTA

Radar-derived rainfall total—In inches

Study area

LAKE SUPERIOR

WISCONSIN

X

2.84

0 15 30 60 MILES

0 15 30 60 KILOMETERS

Base from Minnesota Department of Natural Resources, 1993, 1:24,000 

and 1:100,000 and U.S. Geological Survey digital data, 1:200,000 

Universal Transverse Mercator projection, Zone 15

Figure 2. Distribution of 2-day rainfall totals for 7 a.m. Central Daylight Time June 19 through 7 a.m. Central Daylight Time 

June 21, 2012, and rainfall totals at selected National Weather Service (NWS) Cooperative Observing—Fischer Porter 

precipitation stations. Rainfall data provided by Steve Gohde and Diane Cooper of the National Weather Service (written 

commun., 2012).
Introduction 5

Table 1. Provisional total rainfall for June 19–20, 2012, at selected National Weather Service (NWS) Cooperative 

Observing—Fischer Porter precipitation stations in northeastern Minnesota.

[Total rainfall from Steve Gohde and Diane Cooper of the National Weather Service (written commun., 2012). Annual exceedance probabilities 

from Huff and Angel (1992)]

Precipitation 

station name 

(location 

shown in 

fig. 2)

County

NWS 

station 

identifier

Total 

rainfall 

(inches)

48-hour duration rainfall (inches) for selected annual 

exceedance probabilities1

0.2 0.1 0.04 0.02 0.01

Eveleth St. Louis 212645 2.73 3.21 3.74 4.49 5.06 5.63

Gull Lake Cass 213411 2.84 3.38 3.97 4.86 5.62 6.45

Holyoke Carlton 213863 4.72 3.53 4.03 4.74 5.36 6.02

Pokegama Itasca 216612 4.30 3.38 3.97 4.86 5.62 6.45

Sandy Lake Aitkin 217460 6.27 3.53 4.03 4.74 5.36 6.02

Wales Lake 218613 5.28 3.21 3.74 4.49 5.06 5.63

1

The annual exceedance probability is the probability that a given event will be exceeded or equaled in any given year. For example, the annual 

exceedance probability of the 100-year rainfall is 0.01. In other words, there is a 1-percent chance that the rainfall would be exceeded or equaled 

in any given year.

Cumulative rainfall, in inches

0

1

2

3

4

5

6

7

Eveleth

Gull Lake

Holyoke

Pokegama

Sandy Lake

Wales

National Weather Service—Fischer 

Porter precipitation station

EXPLANATION

Date and time

6/19/12

12 a.m.

6/19/12

12 p.m.

6/20/12

12 a.m.

6/20/12

12 p.m.

6/21/12

12 a.m. 

Figure 3. Cumulative daily rainfall during June 19–20, 2012, at selected National Weather Service 

(NWS) Cooperative Observing—Fischer Porter precipitation stations in northeastern Minnesota.
6 Floods of June 2012 in Northeastern Minnesota

Methods

The methods used to compute magnitudes and annual 

exceedance probabilities of peak streamflows and to collect high-water-mark data are described in this section of the 

report. Methods used to create flood-peak inundation maps 

and water-surface profiles also are described.

Computing the Magnitudes of Peak 

Streamflows

Peak streamflows documented in this study were determined at 35 USGS streamgages (19 continuous-record 

streamgages and 16 crest-stage gages; locations shown in 

fig. 4). Continuous-record streamgages record stream levels 

continuously and for those referred to in this report, data 

are recorded electronically and telemetered to USGS offices 

for processing in near real time. Crest-stage gages (CSGs) 

are partial-record, nonmechanical, nontelemetered gages 

intended to record only the peak (crest) stream level since 

the last site visit.

 For both types of streamgages, the peak streamflow is 

determined by an empirical relation developed between the 

stream level (also referred to as stage or gage height) and 

streamflow (also referred to as discharge) unique to each 

location. These stage-discharge relations at streamgages 

are developed and maintained by relating paired measurements of stage (gage height) and streamflow over the range 

of streamflows through time. Paired measurements used to 

develop a stage-discharge relation are determined most commonly by direct measurement of stage (observed/recorded) 

and streamflow (velocity meter) at the streamgages (Rantz 

and others, 1982); or, if direct measurement is not possible, 

by indirect hydraulic methods (Benson and Dalrymple, 

1967). The stage-discharge relation is developed using available stage/discharge measurements and controlling hydraulic 

features of the channel. Stage-discharge relations can be 

extrapolated slightly beyond the highest measurement of 

stage/streamflow, depending on available information about 

channel geometry and hydraulic conditions (Rantz and others, 1982).

Flood-peak gage heights were obtained either from 

electronic data recorders at continuous-record streamgages or 

from CSGs. At both types of streamgages, peak gage heights 

were confirmed by independent secondary streamgages 

or by nearby high-water marks left as the streams receded 

from flood peak. At a few streamgages that were inundated 

by flood waters, peak gage heights were determined from 

surveyed high-water marks near streamgages. The stage-discharge relation at each streamgage was used to compute peak 

streamflow from the flood-peak gage height. Direct or indirect 

streamflow measurements served as flood-event data points 

for stage-discharge relation verification and extrapolation.

Estimating Annual Exceedance Probabilities 

of Peak Streamflows

The annual exceedance probability (AEP) for a particular 

streamflow is the probability of that streamflow being equaled 

or exceeded in any given year. An AEP of 0.01 has a 1 in 

100 chance or 1-percent risk of being equaled or exceeded 

in any given year (Holmes and Dinicola, 2010). The AEP is 

related to the traditional concept of recurrence interval; by 

definition, the recurrence interval corresponding to a particular 

AEP is equal to 1 divided by the AEP (American Society of 

Civil Engineers, 1953; Holmes and Dinicola, 2010).

Streamflows for selected AEPs (0.10, 0.04, 0.02, 0.01, and 

0.002) were estimated by using one of four methods: (1) the 

Bulletin 17B procedure presented by the Interagency Advisory Committee on Water Data (1982), (2) regional regression 

equations for rural conditions developed by Lorenz and others 

(2010), (3) the Expected Moments Algorithm (Cohn and others, 1997), or (4) weighting of independent estimates (WIE) 

procedure (Cohn and others, 2012; Interagency Advisory Committee on Water Data, 1982). Users of the Bulletin 17B procedure and regional regression equations for rural conditions 

calculate flood probabilities by fitting systematic annual peakstreamflow data to a log-Pearson type III (LPIII) distribution. 

The Expected Moments Algorithm is a generalization of the 

procedures in Bulletin 17B and was designed to better accommodate historical peak-flow data (known peak flows outside 

the period of continuous streamflow data collection) and leftcensored data (peak flows less than what can be measured at 

the streamgage). The WIE method is used to reduce uncertainty 

in the AEP by combining the at-site estimate with the regional 

regression estimate from Lorenz and others (2010) for records 

at sites that are unregulated, unaffected by urbanization, and 

have a drainage area less than 3,000 square miles (mi2) (Lorenz 

and others, 2010; Cohn and others, 2012). The June 2012 

peak streamflows can then be related to the AEPs for each 

streamgage, by bracketing the observed streamflow with the 

streamflow magnitudes associated with the selected AEPs.

Collection of High-Water-Mark Data

High-water marks record the observed elevation of the flood 

peak, and provide the data needed to estimate the maximum 

flood-inundation surface. High-water marks were identified and 

flagged to document inundation levels in selected communities 

most affected by flooding, in addition to the high-water marks 

described previously that were collected at streamgages to confirm peak discharges. These high-water marks were collected by 

staff from the USGS, USACE, and city of Duluth in northeastern Minnesota during June and July 2012 after floodwaters had 

receded. To ensure consistent methods were used to identify and 

document high-water marks, USGS staff met with and provided 

other agency staff with documentation of the methods used.
Methods 7

EXPLANATION

! Study community

Continuous-record streamgage with number

Crest-stage gage with number

Counties with disaster declarations

# 05338500

05335170 #

94° 93° 92° 91° 90°

48°

47°

46°

0 15 30 60 MILES

0 30 60 15 KILOMETERS

Base from Minnesota Department of Natural Resources, 1993, 1:24,000 

and 1:100,000 and U.S. Geological Survey digital data, 1:200,000 

Universal Transverse Mercator projection, Zone 15

#

#

#

#

#

#

#

#

# #

#

# #

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

##

#

#

#

#

!! !

!

!

!

Barnum

Thomson

Carlton

Moose Lake

Fond du Lac, Duluth

Duluth Heights, Duluth

Barnum

Thomson

Carlton

Moose Lake

Fond du Lac, Duluth

Duluth Heights, Duluth

05336200

05335170

05261520

05229450 05221020

05205200

05131750

05125550

04024095

04021690

04020700

04020480

04015415

04015250

04011990 04010530

05336200

05335170

05261520

05229450 05221020

05205200

05131750

05125550

04024095

04021690

04020700

04020480

04015415

04015250

04011990 04010530

05242300

05212700

05207600

05129290

05125000 05126210

04021520

04015438

05338500

05247500

04010500

05336700

05211000

05127500

05124480

04015330

05227500

05129115

04024000

05242300

05212700

05207600

05129290

05125000 05126210

04021520

04015438

05338500

05247500

04010500

05336700

05211000

05127500

05124480

04015330

05227500

05129115

04024000

ST. LOUIS

CASS

LAKE

ITASCA

PINE

AITKIN

COOK

BELTRAMI KOOCHICHING

MORRISON

CROW WING CARLTON

TODD

BENTON

STEARNS ISANTI KANABEC MILLE LACS

HUBBARD

LAKE OF 

THE WOODS WADENA

CHISAGO

Rainy River

Kettle R

Cloquet R

Big Fork R

Pine R

Snake R

Rum R

Red Lake R

St. Louis R

Leech Lake R

Little Fork R

Vermilion R

Rainy River

Kettle R

Cloquet R

Big Fork R

Pine R

Snake R

Rum R

Red Lake R

St. Louis R

Leech Lake R

Little Fork R

Vermilion R

Rapid River

Mississippi R

Crow Wing R

Nemadji R

Rapid River

Mississippi R

Crow Wing R

St. Croix R

Nemadji R

MINNESOTA

Study area

LAKE SUPERIOR

WISCONSIN

Figure 4. Locations of selected U.S. Geological Survey streamgages in the counties with disaster declarations for the floods 

of June 2012 in northeastern Minnesota.
8 Floods of June 2012 in Northeastern Minnesota

Common high-water marks included stain lines and 

debris buildup on buildings, trees, or other structures that identify the highest level reached by the flooding waters. The quality of the high-water marks was subjectively rated in the field 

as excellent, good, fair, or poor by the high-water-mark crews. 

Ratings were based on the clarity of the mark and visual or 

hand-level comparison to nearby marks.

The high-water marks collected by the USGS were 

surveyed using Real-Time Kinematic Global Positioning 

System (RTK-GPS). The survey used a network of continuously operating global positioning system (GPS) stations, 

known as the MnDOT CORS Network (http://www.dot.state.

mn.us/surveying/CORS/CORS.html), that provides real-time 

correction to the rover GPS through a cellular data connection, 

thus eliminating the need for a base station setup. Each survey 

was calibrated to a nearby MnDOT benchmark. Benchmarks 

were chosen based on the vertical accuracy rating of order 2 

or better, as the vertical position of the high-water-mark data 

was deemed most critical. In the case of Carlton, Thomson, 

and Moose Lake, the horizontal order of the nearby usable 

benchmarks were not established. The horizontal position of 

the RTK-GPS survey was then adjusted using a noncalibrated 

GPS measurement at the benchmark or visual correction from 

aerial imagery.

The preferred method of surveying was to set the RTKGPS rover up directly above the high-water mark. However, 

in many cases tree cover or building interference did not 

allow direct surveying of the high-water mark, and then a 

survey point was made a short distance away by transferring 

the elevation of the desired high-water mark to the survey 

point by using a hand level or string level. No correction for 

horizontal position was made. All USGS high-water marks 

were surveyed to an estimated vertical accuracy of 0.1 foot 

(ft), whereas the horizontal position may vary by as much as 

15 ft.

The city of Duluth and the USACE Detroit District collected and surveyed high-water marks along Keene Creek 

(not shown), Kingsbury Creek (not shown), and Miller Creek, 

including in the Duluth Heights neighborhood of Duluth, 

using methods similar to the USGS collection and surveying 

methods. The USACE St. Paul District also provided highwater marks that are routinely collected during flood events, 

primarily at bridge structures and along roads, along selected 

rivers in the Mississippi and Kettle River Basins. The methods and accuracy of these data were not determined in this 

study. All high-water-mark data are included in appendix 1; 

table 1–1 contains the high-water marks for mapped communities of Barnum (Moose Horn River), Carlton (Otter Creek), 

Duluth Heights neighborhood of Duluth (Miller Creek), Fond 

du Lac neighborhood of Duluth (St. Louis River), Moose Lake 

(Moose Horn River and Moosehead Lake), and Thomson 

(Thomson Reservoir outflow near the St. Louis River), and 

table 1–2 contains the high-water marks for additional areas in 

northeastern Minnesota.

Flood-Peak Inundation Maps

Flood-peak inundation maps were produced from the 

high-water marks to show the extent and depth of the peak 

flooding. These maps were produced by use of geographic 

information system (GIS) software and associated programs 

(Morlock and others, 2008; Fitzpatrick and others, 2008; 

Fowler and others, 2010; Ellison and others, 2011), and a 

detailed description of the GIS process is described by Mastin 

and others (2010). The GIS layers of high-water-mark locations and elevations were used in conjunction with LiDARbased 1-meter land-surface elevation data files. LiDAR, an 

acronym for “light detection and ranging,” is remote sensing 

technology that is based on discrete light pulses and measured 

traveltimes. It is used to generate highly accurate three-dimensional representations of the Earth’s surface, termed “digital 

elevation models” (DEMs) (National Oceanic and Atmospheric Administration, 2008). These DEMs were used to 

develop the inundation maps, which then were superimposed 

on the corresponding National Agricultural Imagery Program 

aerial imagery (U.S. Department of Agriculture, 2010). Note 

that LiDAR topography represents “bare earth” elevations, 

such that houses in the flood plain and bridge decks over the 

river centerline are removed. Additionally, LiDAR measurements do not penetrate water, so the elevation in water bodies 

approximately represents the water surface at the time of the 

LiDAR collection flights.

Water-surface elevation was assigned to the stream 

centerline based on nearby high-water-mark data with a linear 

interpolation along the stream centerline between adjacent 

high-water marks. However, the actual water surface may have 

had a different profile than the linear interpolation, hence the 

inundation may have been somewhat different than the mapped 

results. This is especially true at structures where no high-watermark data were available; there may have been a sharper drop 

in the water-surface profile from the upstream to downstream 

side of a culvert or bridge structure. Cross-section lines were 

drawn across the valley representing a line of equal, potential 

peak water-surface elevation and, generally, were perpendicular 

to the direction of flow. A potential water-surface elevation was 

assigned to each cross section based on the water-surface elevation of the stream where they intersect. A triangular irregular 

network (TIN) was produced from the cross-section lines to 

produce a three-dimensional potential water surface. The terrain 

elevation (DEM) was subtracted from the potential water-surface elevation TIN, resulting in a GIS coverage where positive 

values represent the depth of inundation.

Flood-Peak Water-Surface Profiles

Standard USGS methods were used to develop floodpeak water-surface profiles from the high-water-mark elevations and locations (Benson and Dalrymple, 1967; Lumia and 

others, 1986). Flood profiles were produced for the mapped 
Floods of June 2012 in Northeastern Minnesota 9

stream reaches for the six severely affected communities in 

northeastern Minnesota by plotting high-water-mark elevations by mile of stream as measured upstream on the centerline 

of the thalweg from the downstream boundary of each study 

reach. Because the flood-inundation in Thomson represented 

flow across the landscape, the profile was measured along 

an approximate centerline of the flow rather than along the 

nearby stream thalweg. The water surface between high-water 

marks was estimated by linear interpolation. A linear interpolation between high-water marks is an approximation of the 

actual water surface.

Floods of June 2012 in Northeastern 

Minnesota

The estimated AEPs of peak streamflows for the floods of 

June 2012 are presented in this section of the report. Floodpeak inundation maps and flood-peak water-surface profiles 

also are presented.

Magnitudes and Estimated Annual Exceedance 

Probabilities of Peak Streamflows

The magnitudes (flood-peak gage-height data and 

peak-streamflow data) and estimated AEPs from the June 

2012 floods are presented for 34 of the 35 streamgages 

(table 2). The Mississippi River at Willow Beach at Ball 

Club (streamgage 05207600) does not have sufficient historical record to compute AEPs, and the basin characteristics 

are beyond the range applicable by the regression equations. 

New peak-of-record streamflows were recorded at 13 USGS 

streamgages as a result of the heavy rainfall, including the 

St. Louis River at Scanlon (streamgage 04024000), which 

has more than 100 years of streamflow records. Flood-peak 

streamflows in June 2012 had AEPs estimated to be less than 

0.002 (0.2 percent; recurrence interval greater than 500 years) 

for five streamgages, and between 0.002 and 0.01 (1 percent; recurrence interval greater than 100 years) for four 

streamgages (table 2).

The timing of peak flows for streams of differing size 

is evident in the plot of the stage hydrographs for selected 

streamgages for the flood event (fig. 5). Streams and smaller 

rivers were quick to respond to the intense rainfall, such as 

the Knife River near Two Harbors (04015330), which peaked 

at an estimated 25,000 cubic feet per second (ft3/s) on June 

20, 2012, exceeding the previous peak of record of 7,440 ft3/s 

from May 1979 (table 2). Some larger rivers also had rapid 

rises in streamflow in response to the intense rainfalls late 

on June 19, 2012, such as the St. Louis River at Scanlon 

(04024000), which peaked at 45,300 ft3/s on June 21, 2012 

(table 2). Other large rivers, such as the Mississippi River, had 

a more delayed response time as the water accumulated from 

tributaries; the peaks also were affected by dam and reservoir 

management activities (fig. 5).

Flood-Peak Inundation Maps and Water-Surface 

Profiles

Flood-peak inundation maps (figs. 2–1 to 2–6 in appendix 2) and flood-peak water-surface profiles (figs. 3–1 to 3–6 

in appendix 3) were produced for the six communities of 

Barnum (Moose Horn River), Carlton (Otter Creek), Duluth 

Heights neighborhood of Duluth (Miller Creek), Fond du 

Lac neighborhood of Duluth (St. Louis River), Moose Lake 

(Moose Horn River and Moosehead Lake), and Thomson 

(Thomson Reservoir outflow near the St. Louis River), respectively. Personnel from the USGS, USACE Detroit District, and 

city of Duluth flagged and surveyed high-water marks in June 

and July 2012 in these six most severely affected communities. The city of Duluth and the USACE Detroit District also 

surveyed high-water marks along Keene Creek (not shown), 

Kingsbury Creek (not shown), and the lower part of Miller 

Creek. The USACE St. Paul District collected high-water 

marks at bridge structures along the Mississippi River and 

Diversion Channel in the Mississippi River Basin, and along 

the Moose Horn, Kettle, Pine, and Willow Rivers in the Kettle 

River Basin. Descriptions of all the high-water marks are 

listed in appendix 1; only the locations of high-water marks in 

the six mapped communities are shown in the report figures.

A flood-peak inundation map was generated for each 

community showing the maximum extent and depth of floodwaters in and around the community (appendix 2). Inundation maps contain locations and elevations of the high-water 

marks, along with an indication of whether each high-water 

mark was used to develop the flood-peak water-surface. If a 

data point was substantially higher or lower when compared 

to neighboring points, the point in question was not used 

in interpolating the water surface for the inundation map. 

For example, high-water marks MOOSE1 and MOOSE2 

(table 1–1) in the community of Moose Lake were substantially lower than other high-water marks in the area and were 

not used to interpolate the water surface for mapping the flood 

inundation (figs. 2–5 and 3–5). It is assumed that these marks 

were left as flood waters receded and were not representative of the peak water surface. In the Fond du Lac neighborhood of Duluth, numerous high-water marks were collected 

in proximity to each other; however, the elevations do not 

agree in connecting a single peak water-surface profile along 

the St. Louis River (figs. 2–4 and 3–4). The elevations from 

high-water-mark identifiers FDL1, FDL3, and FDL10 were 

used in the flood-inundation mapping for the upstream part of 

the profile, whereas the other nearby high-water marks that are 

all lower in elevation and likely not representative of the peak 

water surface were disregarded. Additionally, high-water-mark 

identifier FDL9 was on a hill with substantial flow heading 

downslope towards the St. Louis River, and was not used for 

the water-surface profile along the St. Louis River.
Table 2. Provisional flood-peak gage heights, peak streamflows, and annual exceedance probabilities of peak streamflows during the floods of June U.S. Geological Survey streamgages in northeastern Minnesota. [mi2,square miles; ft, feet; NGVD 29, National Geodetic Vertical Datum of 1929; WY, water year; ft3/s, cubic feet per second; %, percent; Minn., Minnesota; e, estimated, >, gre--, data not available] Station number Stream and community Drainage area (mi2) Gage vertical datum (ft above NGVD 29) Water years1 with peak-flow records Length of record of annual peaks (years) Peak flow for period of record prior to WY 2012 Peak flow for June 19–30, 2012 floods A

exce

prob

for J

peak s

Date Gage height (ft above gage datum) Stream- flow (ft3/s) Date Gage height (ft above gage datum) Stream- flow (ft3/s) 04010500 Pigeon River at Middle Falls near Grand Portage, Minn. 609 787.58 1924–2011 88 5/5/1934 7.60 11,000 6/20/2012 8.76 3,700 > 

404010530 Reservation River near Hovland, Minn. 16.5 660.00 1991–92, 2000–11 14 7/31/2009 3.68 > 1,350 6/20/2012 4.05 1,300 0.1

404011990 Cascade River at Forest Road 45 near Grand Marais, Minn. 87.6 1,500.00 1985–2011 27 4/24/2001 13.36 1,810 6/20/2012 11.38 6671 > 

404015250 Silver Creek tributary near Two Harbors, Minn. 3.62 Undetermined7 1965–2011 47 9/20/1972 17.08 1,880 6/20/2012 17.50 82,200 0.01

04015330 Knife River near Two Harbors, Minn. 83.6 Undetermined7 1975–2011 37 5/10/1979 11.16 7,440 6/20/2012 12.81 8,925,000 < 

404015415 Lake Superior tributary at West 9th Street in Duluth, Minn. 1.81 Undetermined7 2001–11 11 8/2/2010 9.72 175 6/20/2012 11.61 8740 < 

1104015438 St. Louis River near Skibo, Minn. 101 1,500.00 -- -- -- -- -- 6/24/2012 20.79 8813 > 404020480 North Branch Whiteface River near Fairbanks, 

Minn.

17.1 Undetermined7 1979–2011 33 4/23/1979 13.67 660 6/21/2012 13.90 649 0.0

404020700 Bug Creek at Shaw, Minn. 24.8 Undetermined7 1979–2011 33 7/5/1999 18.00 91,350 6/21/2012 18.10 81,580 0.01

04021520 Stoney Brook at Pine Drive near Brookston, 

Minn.

74.0 Undetermined7 2005–11 7 4/27/2008 7.70 453 6/21/2012 12.34 81,170 0.0

404021690 Cloquet River near Toimi, Minn. 40.8 1,700.00 1986–2011 26 7/4/1993 9.06 1,540 6/21/2012 8.30 1,110 0.0

04024000 St. Louis River at Scanlon, Minn. 3,430 1,101.23 1908–2011 104 5/9/1950 -- 1337,900 6/21/2012 16.62 845,300 < 

404024095 Nemadji River near Holyoke, Minn. 127 756.12 1972–2011 40 8/3/2011 18.60 5,300 6/20/2012 21.05 8,99,700 < 

05124480 Kawishiwi River near Ely, Minn. 254 Undetermined7 1967–2011 45 5/4/2001 6.07 1,870 6/24/2012 4.91 793 > 05125000 South Kawishiwi River near Ely, Minn. -- 1,430.00 1952–61, 

1976–78, 

2003–11

22 4/21/1976 7.18 4,980 6/26/2012 5.69 2,560 > 

405125550 Stony River near Babbitt, Minn. 215 Undetermined7 1976–80, 

1986–2011

31 4/19/1976 8.71 2,490 6/26/2012 7.31 1,480 > 

05126210 South Kawishiwi River above White Iron Lake 

near Ely, Minn.

837 Undetermined7 1976–78, 

2003–11

12 4/22/1976 11.42 8,080 6/26/2012 9.49 4,890 > 

05127500 Basswood River near Winton, Minn. 1,740 1,296.80 1926–27, 

1930–2011

84 5/24/1950 6.94 1315,600 6/30/2012 5.59 4,370 > 

05129115 Vermilion River near Crane Lake, Minn. 905 1,180.00 1979–2011 33 4/1979 15.15 4,600 6/21/2012 10.20 61,520 > 

05129290 Gold Portage outlet from Kabetogama Lake 

near Ray, Minn.

-- Undetermined7 1983–94, 

1998–2011

26 5/29/2001 (14) 1,310 6/21/2012 18.38 6770 > 

405131750 Big Fork River near Bigfork, Minn. 606 Undetermined7 1973–2011 38 4/22/1979 15.48 2,830 6/21/2012 < 10.59 6< 783 > 

405205200 Boy River near Remer, Minn. 289 Undetermined7 1986–2011 26 7/23/1987 11.64 660 6/22/2012 11.14 420 > 

05207600 Mississippi River at Willow Beach at Ball 

Club, Minn.

2,850 Undetermined7 2008–11 4 2/18/2011 14, 1511.50 132,720 6/24/2012 8.71 61,410 Unde

05211000 Mississippi River at Grand Rapids, Minn. 3,370 1,242.03 1942–2011 70 9/3/1948 15.20 1312,500 6/19/2012 8.41 63,190 > 

05212700 Prairie River near Taconite, Minn. 371 1,294.81 1968–83, 

2001–11

27 4/17/1969 11.81 3,260 6/27/2012 7.91 6942 > 
/s, cubic feet per second; %, percent; Minn., Minnesota; e, estimated, >, gre

Provisional flood-peak gage heights, peak streamflows, and annual exceedance probabilities of peak streamflows during the floods of June 

, water year; ft3

Table 2.

 Geological Survey streamgages in northeastern Minnesota. —Continued

square miles; ft, feet; NGVD 29, National Geodetic Vertical Datum of 1929; WY

U.S.

,[mi

2

--, data not available]

Station 

number Stream and community

Drainage

area 

(mi2

)

Gage

vertical

datum

(ft above

NGVD 29)

Water 

years1 with 

peak-flow 

records

Length

of record

of annual

peaks

(years)

Peak flow for period of record prior 

to WY 2012

Peak flow for June 19–30, 2012 

floods A

exce

prob

for J

peak s

Date

Gage height

(ft above 

gage datum)

Streamflow

(ft3/s)

Date

Gage height

(ft above

gage datum)

Streamflow

(ft3/s)

405221020 Willow River below Palisade, Minn. 523 Undetermined7 1972–2011 40 4/25/1979 17.25 3,730 6/28/2012 17.43 3,440 0.1

05227500 Mississippi River at Aitkin, Minn. 6,140 1,182.41 1888–99, 

1902–2011

112 5/20/1950 22.49 1320,000 6/28/2012 18.71 15,100 0.0

405229450 Pine River near Pine River, Minn. 261 1,279.00 1986–2011 26 5/14/1999 5.15 1,520 6/23/2012 5.74 8,92,000 0.01

05242300 Mississippi River at Brainerd, Minn. 7,320 1,146.96 1988–2011 24 4/30/2001 16.70 1317,500 6/28/2012 17.61 817,900 0.005247500 Crow Wing River near Pillager, Minn. 3,760 1,151.00 1965, 1969, 

1970–2011

43 4/14/1965 1318,300 6/24/2012 7.35 66,860 > 

405261520 Nokasippi River near Fort Ripley, Minn. 193 Undetermined7 1986–2011 26 6/26/2003 15.17 1,160 6/22/2012 15.10 81,200 0.1405335170 Crooked Creek near Hinckley, Minn. 94.4 Undetermined7 1986–2011 26 4/23/2001 16.65 2,100 6/22/2012 15.02 61,380 > 405336200 Glaisby Brook near Kettle River, Minn. 27.0 1,105.00 1960–2011 52 7/22/1972 10.18 1,370 6/20/2012 12.26 8,9> 2,000 0.01

05336700 Kettle River below Sandstone, Minn. 868 931.50 1965,

1968–2011

45 7/23/1972 15.38 17,200 6/22/2012 18.22 824,800 < 

05338500 Snake River near Pine City, Minn. 974 Undetermined7 1914–17, 

1950, 

1952–2011

61 7/27/1972 10.38 14,300 6/26/2012 5.66 62,930 > 

 water year is the 12-month period from October 1 through September 30 and is designated by the calendar year in which it ends. For some sites, records include annual pea

Advisory Committee on 

AThe annual exceedance probability is the probability that a given event magnitude will be equaled or exceeded in any given year and is the reciprocal of the recurrence interv

The annual exceedance prob

stimates were 

is the average interval of time within which the given flood will be equaled or exceeded once (American Society of Civil Engineers, 1953, p. 1221). 

ater Data, 1982, appendix 8). The independent e

Water Data, 1982).

interval of 10 years is 0.10 (10%); for 25 years, 0.04 (4%); for 50 years, 0.02 (2%); and for 100 years, 0.01 (1%).

Advisory Committee on 

W

Streamflow computed from Expected Moments Algorithm (Cohn and others, 1997).U.S. Geological Survey crest-stage or peak-stage gage.Streamflow from weighting of independent estimates (WIE) procedure (Interagency 

August 201

ers (2010).

June 2012 peak was not peak of water year 2012.Elevation from vertical datum has not been established.New streamflow peak of record.Streamflow is an estimate.

Streamflow computed from Bulletin 17B, Guidelines for Determining Flood Flow Frequency (Interagency 

1.

10

Streamgage was installed 

Streamflow from Lorenz and others (2010) regression equations.

fected to unknown degree by regulation or diversion.

12

Streamflow af 13Gage height not the maximum for the year.Gage height affected by backwater.

123456789111415

Recurrence-interval flows have not been established. One or more basin characteristics are beyond the range used for development of models from regression analysis. 16
12 Floods of June 2012 in Northeastern Minnesota

The maps were checked by USGS surveying and 

high-water-mark personnel, and the high-water marks were 

compared spatially to check for mathematical or other errors. 

Anecdotal information from local residents was used to 

interpret the water-surface profile between high-water marks 

and to extrapolate the area of inundation beyond the surveyed 

area as necessary. The maps also were visually compared 

to photographs and videos of flooding available online and 

from local residents, as well as aerial photographs taken by 

MnDOT personnel from a helicopter during the flooding. Not 

all photographs and videos were taken during peak flooding 

and they are indicative of the minimum area that was flooded. 

Aerial photographs were used to extrapolate the maps beyond 

the extent of surveyed high-water marks; for example, the 

inundation in Fond du Lac neighborhood of Duluth extended 

downstream and to the north away from the river corridor 

where most high-water marks were found and surveyed. The 

elevation and extent of the flood waters were inferred from 

the MnDOT aerial photographs at easily identifiable edges of 

water across the roadways.

Flood-peak water-surface profiles were produced from 

the high-water-mark data along the thalweg (appendix 3). 

The profiles include only the high-water marks that were used 

to determine the elevation of the flood-peak water-surface 

(appendix 2). The only exception is that the water-surface profile for Thomson does not include high-water-marks ETHOM1 

and ETHOM2, which were used to map the water-surface 

elevation of the east side of town but are not adjacent to the 

primary flow path that is represented in the water-surface 

profile (figs. 2–6 and 3–6). Flood-peak profiles show how 

the flood-peak inundation surface and slope varied along the 

stream reach through each of the six communities. Locations 

of bridge crossings were added to the profiles to provide additional context.

Although few high-water marks were identified in 

Barnum (fig. 2–1), photographs taken by residents during 

the floods also provided information on what areas of town 

were flooded by the Moose Horn River. Southwest of town, 

inundation was mapped by assuming that floodwaters spilled 

out of the channel and backed up this drainage area that normally flows north into the Moose Horn River during low-flow 

conditions.

The city of Carlton also is located near Thomson Reservoir; however, flooding in Carlton originated from Otter Creek 

Stage, in feet above local gage datum

0

2

4

6

8

10

12

14

16

18

20

22

24

6/10/2012 6/17/2012 6/24/2012 7/1/2012 7/8/2012 7/15/2012 7/22/2012 7/29/2012

Kettle River below Sandstone (05336700) Knife River near Two Harbors (04015330)

St. Louis River at Scanlon (04024000) Stoney Brook at Pine Drive near Brookston (04021520)

Mississippi River at Aitkin (05227500) Estimated

Mississippi River at Brainerd (05242300)

EXPLANATION

Figure 5. Provisional stage hydrographs at selected U.S. Geological Survey streamgages in 

northeastern Minnesota for June 10 through July 29, 2012.
Description of Flood Damages and Effects 13

on the south side of town. Otter Creek flows east until it joins 

the St. Louis River downstream of Thomson Reservoir. As the 

floodwaters in Otter Creek rose, they spilled northward across 

the train tracks and flowed through town along two pathways 

(fig. 2–2). The floodwaters likely flowed north of town, then 

turned and flowed east along a drainage path south of Thomson Reservoir.

The flooding in the Duluth Heights neighborhood in 

Duluth was from Miller Creek, and affected businesses along 

Miller Trunk Highway (fig. 2–3). Parts of Miller Trunk Highway were inundated and the road was temporarily closed.

Also in Duluth, the Fond du Lac neighborhood was 

substantially inundated by the St. Louis River (fig. 2–4). 

Floodwaters inundated most residences along the north side of 

the river. Highway 23 was underwater in several locations and 

was closed to traffic.

The town of Moose Lake was flooded along Moosehead 

Lake on the Moose Horn River (fig. 2–5). Much of the rain 

that contributed to flooding in Moose Lake fell on the contributing watershed farther upstream. The Moose Horn River 

enters the northeast corner of Moosehead Lake, and exits in 

its southwest corner. The Portage River also is tributary to 

Moosehead Lake, entering at the east side. The water surface of the lake was mapped at an elevation of 1,052.5 ft for 

the entire area of the expanded lake. Floodwaters inundated 

houses, schools, and a campground.

The St. Louis River exits Thomson Reservoir (fig. 2–6) 

at the dam west of the town of Thompson. Although the 

flooding along the St. Louis River washed out part of the 

Highway 210 roadway, this area was not in the study area 

for inundation mapping. Floodwaters spilled out of Thomson Reservoir at several small dam structures and flowed 

overland into the town of Thomson. The more destructive 

floodwaters flowed overland and south along Vermillion 

Street, flooding houses and causing substantial damage to 

the street. This water continued to flow southeast across 

Highway 210 and joined the St. Louis River south of the 

study limit (fig. 2–6). On the eastern side of Thomson, the 

floodwaters flowed down the forested hill from the reservoir and flooded houses along Dalles Avenue. Two culverts 

at the study boundary (indicated by the deeper inundation 

depths at the southern study boundary on fig. 2–6) could not 

pass all the flow to the south, which backed up water and 

caused it to flow west along Dalles Avenue and join with 

the floodwaters from Vermillion Street. Farther to the east, a 

diversion canal that conveys water from Thomson Reservoir 

downstream to Minnesota Power facilities also was beyond 

the study limit.

Description of Flood Damages and 

Effects

Heavy rainfall on already saturated land caused widespread flash flooding and river flooding in northeastern 

Minnesota in June 2012. Transportation disruptions were 

widespread, and road closures were common across Itasca, 

Aitkin, Carlton, southern Lake, and southern St. Louis Counties. Damages included residences, infrastructure, businesses, 

public parks, and recreation facilities. The most severely 

affected communities, and the focus of this study for inundation mapping, included Barnum (Moose Horn River), Carlton (Otter Creek), Duluth Heights neighborhood of Duluth 

(Miller Creek), Fond du Lac neighborhood of Duluth (St. 

Louis River), Moose Lake (Moose Horn River and Moosehead Lake), and Thomson (Thomson Reservoir outflow near 

the St. Louis River). Nearby communities such as Floodwood 

(not shown), Fond du Lac Indian Reservation (not shown), 

and Cloquet (not shown) also received extensive flooding and 

damage and were inspected by field crews but were beyond 

the scope of this study and not surveyed for high-water marks.

The floods in northeastern Minnesota caused more than 

an estimated $100 million dollars in damages. Following is 

a summary of damage assessment compiled after June 2012 

primarily from news releases and information by the Minnesota Department of Public Safety, Homeland Security and 

Emergency Management (2012):

•	 Road closures included Interstate 35 through 

Duluth and south of Carlton, as well as numerous 

State highways and local roads.

•	 Evacuations included Barnum, Thomson, and part 

of Moose Lake (Carlton County), parts of Fond 

du Lac neighborhood of Duluth, and Willow 

River (not shown; Pine County).

•	 Evacuation sites were set up in Duluth, Carlton, 

Scanlon (not shown), and Askov (not shown).

•	 Red Cross staffed evacuation sites, and Salvation 

Army provided meals.

•	 Food and drinking-water distribution points were 

set up in the affected areas.

•	 The Lake Superior Zoo in Duluth experienced 

damage as Kingsbury Creek (not shown) 

flooded, including the loss of 14 animals and 

damage of structures. Several other animals 

were swept from their enclosures but were safely 

rescued (Lake Superior Zoo, 2012).

•	 Jay Cooke State Park (not shown) was closed due 

to severe damage to the entrance route on Highway 210. The park’s iconic swinging bridge over 

the St. Louis River was severely damaged.

•	 Other parks (not shown on maps) were temporarily closed or had restricted access, including Savanna Portage State Park, Moose Lake 

State Park, Willard Munger State Trail, Cuyuna 

Country State Recreation Area, and Soo Line and 

Blind Lake ATV trails in Aitkin County.
14 Floods of June 2012 in Northeastern Minnesota

Preliminary damage assessments were done in 13 counties and the Fond du Lac Indian Reservation in the days 

after the flood. Assessment teams included Federal officials 

from FEMA, State officials from MHSEM, and local officials. On July 6, 2012, President Obama declared a major 

disaster existed in northeastern and central Minnesota for the 

June 14–21, 2012, storm and flood events (Federal Emergency Management Agency, 2012). The disaster declaration 

brought much needed additional assistance for residents and 

businesses. This declaration made public assistance requested 

by the Governor available to State and eligible local governments, and certain private nonprofit organizations on a costsharing basis for emergency work and the repair or replacement of facilities damaged by the severe flooding in Aitkin, 

Carlton, Cass, Cook, Crow Wing, Dakota, Goodhue, Itasca, 

Kandiyohi, Lake, Meeker, Pine, Rice, St. Louis, and Sibley 

Counties, as well as the Fond du Lac (not shown), Grand 

Portage (not shown), and Mille Lacs (not shown) Indian Reservations. This declaration also made Hazard Mitigation Grant 

Program assistance requested by the Governor available for 

hazard-mitigation measures statewide.

Summary

During June 19–20, 2012, heavy rainfall, as much as 

10 inches locally reported, caused severe flooding across 

northeastern Minnesota. The floods were exacerbated by wet 

antecedent conditions from a relatively rainy spring, with 

May 2012 as one of the wettest Mays on record in Duluth. The 

June 19–20, 2012, rainfall event set new records in Duluth, 

including greatest 2-day precipitation with 7.25 inches of rain. 

The heavy rains fell on three major watersheds: the Mississippi Headwaters; the St. Croix, which drains to the Mississippi River; and Western Lake Superior, which includes the St. 

Louis River and other tributaries to Lake Superior. Widespread 

flash and river flooding in northeastern Minnesota that resulted 

from the heavy rainfall caused more than $100 million dollars 

in damages. In all, nine counties in northeastern Minnesota 

were declared Federal disaster areas as a result of the flooding. The June 2012 flooding caused widespread transportation 

disruptions across Itasca, Aitkin, Carlton, southern Lake, and 

southern St. Louis Counties. Damages included residences, 

infrastructure, businesses, public parks, and recreation 

facilities.

Peak-of-record streamflows were recorded at 

13 U.S. Geological Survey streamgages as a result of the 

heavy rainfall. Flood-peak gage heights, peak streamflows, and annual exceedance probabilities were tabulated 

for 35 U.S. Geological Survey streamgages. Flood-peak 

streamflows in June 2012 had annual exceedance probabilities estimated to be less than 0.002 (0.2 percent; recurrence 

interval greater than 500 years) for five streamgages, and 

between 0.002 and 0.01 (1 percent; recurrence interval greater 

than 100 years) for four streamgages. High-water marks were 

identified and tabulated for the most severely affected communities of Barnum (Moose Horn River), Carlton (Otter Creek), 

Duluth Heights neighborhood of Duluth (Miller Creek), Fond 

du Lac neighborhood of Duluth (St. Louis River), Moose 

Lake (Moose Horn River and Moosehead Lake), and Thomson (Thomson Reservoir outflow near the St. Louis River). 

Flood-peak inundation maps and water-surface profiles were 

produced for these six severely affected communities. The 

inundation maps were constructed in a geographic information 

system by combining high-water-mark data with high-resolution digital elevation model data. The flood maps and profiles 

show the extent and depth of flooding through the communities and can be used for flood response and recovery efforts by 

local, county, State, and Federal agencies.

References Cited

American Society of Civil Engineers, 1953, Report of the 

subcommittee on the joint division committee on floods: 

American Society of Civil Engineers Transactions, v. 118, 

p. 1,220–1,230.

Benson, M.A., and Dalrymple, Tate, 1967, General field and 

office procedures for indirect measurements: U.S. Geological Survey Techniques of Water-Resources Investigations, 

book 3, chap. A1, 30 p.

Charlton, Ro, 2009, Fundamentals of fluvial geomorphology: 

New York, Routledge, 234 p.

Cohn, T.A., Berenbrock, Charles, Kiang, J.E., and Mason, 

R.R., Jr., 2012, Calculating weighted estimates of peak 

streamflow statistics: U.S. Geological Survey Fact Sheet 

2012–3038, 4 p. (Also available at http://pubs.usgs.gov/

fs/2012/3038/.)

Cohn, T., Lane, W.L., and Baier, W.G., 1997, An algorithm for 

computing moments-based flood estimates when historical 

flood information is available: Water Resources Research, 

v. 33, no. 9, p. 2,089–2,096.

Ellison, C.A., Sanocki, C.A., Lorenz, D.L., Mitton, G.B., and 

Kruse, G.A., 2011, Floods of September 2010 in Southern 

Minnesota: U.S. Geological Survey Scientific Investigations 

Report 2011–5045, 37 p., 3 app. (Also available at http://

pubs.usgs.gov/sir/2011/5045/.)

Federal Emergency Management Agency, 2012, Minnesota 

severe storms and flooding (DR-4069): accessed October 19, 2012, at http://www.fema.gov/disaster/4069.

Fitzpatrick, F.A., Peppler, M.C., Walker, J.F., Rose, W.J., 

Waschbusch, R.J., and Kennedy, J.L., 2008, Flood of June 

2008, southern Wisconsin: U.S. Geological Survey Scientific Investigations Report 2008–5235, 24 p. (Also available 

at http://pubs.usgs.gov/sir/2008/5235/.)
References Cited 15

Fowler, K.K., Kim, M.H., Menke, C.D., and Arvin, D.V., 

2010, Flood of September 2008 in northwestern Indiana: 

U.S. Geological Survey Open-File Report 2010–1098, 20 p. 

(Also available at http://pubs.usgs.gov/of/2010/1098/.)

Graning, Amanda, and Hluchan, Rick, 2012, Summary of 

Duluth flash flood event, June 19th–20th 2012: Duluth, 

Minn., National Weather Service, 5 p., accessed October 19, 2012, at http://www.crh.noaa.gov/images/dlh/

StormSummaries/2012/June19_flood/DuluthSummary.pdf.

Holmes, R.R., Jr., Dinicola, Karen, 2010, 100-Year flood—It’s 

all about chance: U.S. Geological Survey General Information Product 106, 1 sheet. (Also available at http://pubs.

usgs.gov/gip/106/.) 

Huff, F.A., and Angel, J.R., 1992, Rainfall frequency atlas of 

the Midwest: Champaign, Illinois State Water Survey, Bulletin 71, 141 p.

Interagency Advisory Committee on Water Data, 1982, Guidelines for determining flood flow frequency, Bulletin 17B of 

the Hydrology Subcommittee: Reston, Virginia, U.S. Geological Survey, Office of Water Data Coordination, 183 p.

Lake Superior Zoo, 2012, Support your zoo: accessed December 6, 2012, at http://lszoo.org/support.htm.

Langbein, W.B., and Iseri, K.T., 1960, General introduction 

and hydrologic definitions, Manual of hydrology, part 1, 

General surface-water techniques: U.S. Geological Survey 

Water-Supply Paper 1541–A, 29 p.

Lorenz, D.L., Sanocki, C.A., and Kocian, M.J., 2010, Techniques for estimating the magnitude and frequency of peak 

flows on small streams in Minnesota based on data through 

water year 2005: U.S. Geological Survey Scientific Investigations Report 2009–5250, 54 p.

Lumia, Richard, Burke, P.M., and Johnston, W.H., 1986, 

Flooding of December 29, 1984, through January 2, 1985, 

in northern New York State, with flood profiles of the 

Black and Salmon Rivers: U.S. Geological Survey WaterResources Investigations Report 86–4191, 53 p.

Mastin, M.C., Gendaszek, A.S., and Barnas, C.R., 2010, Magnitude and extent of flooding at selected river reaches in 

western Washington, January 2009: U.S. Geological Survey 

Scientific Investigations Report 2010–5177, 34 p. (Also 

available at http://pubs.usgs.gov/sir/2010/5177/.)

Minnesota Department of Natural Resources State Climatology Office, 2012a, Wet May 2012: accessed October 29, 2012, at http://climate.umn.edu/doc/journal/

wet_may2012.htm.

Minnesota Department of Natural Resources State Climatology Office, 2012b, Flooding rains—June 14, 2012: accessed 

October 29, 2012, at http://climate.umn.edu/doc/journal/

flood14_150612.htm.

Minnesota Department of Natural Resources State Climatology Office, 2012c, Wet growing season in eastern Minnesota: accessed October 29, 2012, at http://climate.umn.edu/

doc/journal/wet_2012.htm.

Minnesota Department of Natural Resources State Climatology Office, 2012d, Flooding rains in northeast Minnesota: 

June 19–20, 2012: accessed October 29, 2012, at http://

climate.umn.edu/doc/journal/duluth_flooding_120620.htm.

Minnesota Department of Public Safety, Homeland Security 

and Emergency Management, 2012, 2012 Northeast and 

central Minnesota flooding (DR–4069): accessed November 

26, 2012, at https://dps.mn.gov/divisions/hsem/minnesotarecovers/Pages/june-2012-flooding.aspx.

Minnesota Department of Transportation, 2012, MnDOT 

CORS GPS Network: accessed December 6, 2012, at http://

www.dot.state.mn.us/surveying/CORS/CORS.html.

Morlock, S.E., Menke, C.D., Arvin, D.V., and Kim, M.H., 

2008, Flood of June 7–9, 2008, in central and southern 

Indiana: U.S. Geological Survey Open-File Report 2008–

1322, 15 p., 3 app. (Also available at http://pubs.usgs.gov/

of/2008/1322/.)

National Oceanic and Atmospheric Administration, 2008, 

LIDAR 101—An introduction to LiDAR technology, data, 

and applications: accessed November 26, 2012, at http://

www.csc.noaa.gov/digitalcoast/_/pdf/What_is_Lidar.pdf.

National Weather Service, 2009, National Weather Service 

glossary: accessed October 29, 2012, at http://www.weather.

gov/glossary/.

Rantz, S.E., and others, 1982, Measurement and computation 

of streamflow—Volume 1, Measurement of stage and discharge, and volume 2, Computation of discharge: U.S. Geological Survey Water-Supply Paper 2175, 631 p.

Skinner, K.D., 2009, Evaluation of LiDAR-acquired bathymetric and topographic data accuracy in various hydrogeomorphic settings in the lower Boise River, southwestern 

Idaho, 2007: U.S. Geological Survey Scientific Investigations Report 2009–5260, 12 p. (Also available at http://

pubs.usgs.gov/sir/2011/5051/.)

U.S. Department of Agriculture, 2010, National Agricultural 

Imagery Program (NAIP) digital orthorectified images 

(DOQ), Minnesota, 2010: accessed December 5, 2012, 

at http://www.mngeo.state.mn.us/chouse/metadata/naip10.

html.

U.S. Geological Survey, 2011, Water resources of the 

United States—2011 Annual Data Report—Definition of 

terms: U.S. Geological Survey Water-Data Report WDR–

US–2011, accessed November 19, 2012, at http://wdr.water.

usgs.gov/wy2011/termDefs.html. 
16 Floods of June 2012 in Northeastern Minnesota
Glossary 17

Glossary

The following definitions, except where otherwise noted, are from Langbein and Iseri 

(1960).

annual exceedance probability The probability that a given event magnitude will be 

exceeded or equaled in any given year. The 

annual exceedance probability is directly 

related to the recurrence interval. For example, there is a 1-percent chance that the 100-

year peak flow will be exceeded or equaled in 

any given year. A flood probability of 0.01 has 

a recurrence interval of 100 years. The recurrence interval corresponding to a particular 

flood probability is equal to one divided by 

the flood probability (Holmes and Dinicola, 

2010).

cold front A zone separating two air masses, 

of which the cooler, denser mass is advancing and replacing the warmer mass (National 

Weather Service, 2009).

continuous-record streamgage A site where 

data are collected with sufficient frequency to 

define daily mean values and variations within 

a day.

crest-stage gage A partial-record 

streamgage that is nonmechanical, nontelemetered, and intended to record only the peak 

(crest) stream level since the last site visit.

flood peak The highest value of the stage or 

discharge attained by a flood; thus, peak stage 

or peak discharge. “Flood crest” has nearly 

the same meaning, but because it connotes the 

top of the flood wave, it is properly used only 

in referring to stage—thus, “crest stage,” but 

not “crest discharge.”

flood profile A graph of elevation of the 

water surface of a river in flood, plotted as 

ordinate, against distance, measured in the 

downstream direction, plotted as abscissa. A 

flood profile may be drawn to show elevation 

at a given time or crests during a particular 

flood.

gage height The water-surface elevation 

referred to some arbitrary gage datum. Gage 

height is often used interchangeably with the 

more general term “stage,” although gage 

height is more appropriate when used with a 

reading on a gage.

high-water mark The highest stage reached 

by a flood that has been maintained for a 

sufficient period to leave evidence on the 

landscape (Benson and Dalrymple, 1967).

recurrence interval (return period) The 

average interval of time within which the 

given flood will be equaled or exceeded once. 

The recurrence interval is directly related to 

the flood probability. The recurrence interval 

corresponding to a particular flood probability 

is equal to 1 divided by the flood probability. 

For example, a 100-year recurrence interval 

has a flood probability of 0.01.

streamflow The discharge in a natural 

channel. Although the term “discharge” can 

be applied to the flow of a canal, the word 

“streamflow” uniquely describes the discharge 

in a surface stream course.

streamgage A site on a stream, canal, lake, 

or reservoir where systematic observations of 

stage, discharge, or other hydrologic data are 

obtained (U.S. Geological Survey, 2011). In 

this report, when it is necessary to distinguish 

between specific types of instrumentation or 

data used at a streamgage, the following terms 

are used: “continuous-record streamgage” is 

used for the sites where continuous-record 

data are collected, and “crest-stage gage” is 

used for the sites where partial-record data are 

collected.

thalweg The area of maximum water velocity within a channel flow (Charlton, 2009).

warm front A transition zone between 

a mass of warm air and the colder air it is 

replacing (National Weather Service, 2009).
18 Floods of June 2012 in Northeastern Minnesota
Appendix 1. High-Water-Mark Descriptions 19

Appendix 1. High-Water-Mark Descriptions
20 Floods of June 2012 in Northeastern Minnesota

Table 1–1. High-water-mark descriptions for the mapped communities of Barnum, Carlton, Duluth Heights neighborhood in Duluth, 

Fond du Lac neighborhood in Duluth, Moose Lake, and Thomson for the floods of June 2012 in northeastern Minnesota.

[Vertical coordinate data are referenced to the North American Vertical Datum of 1988 (NAVD 88). Horizontal coordinate data are referenced to the North 

American Datum of 1983. Approximate quality ratings of high-water marks: Excellent, plus or minus (±) 0.02 foot; Good, ± 0.05 foot; Fair, ± 0.1 foot; and 

Poor, greater than 0.10 foot (Lumia and others, 1986).°, degrees; ʹ, minutes; ʺ, seconds; --, not available; USACE, U.S. Army Corps of Engineers; USGS, 

U.S. Geological Survey]

Elevation 

(feet above 

NAVD 88)

Latitude Longitude High-watermark quality High-water-mark description

High-watermark 

identifier

Agency that collected data

Barnum

1,099.0 46°30ʹ56.8ʺ 92°41ʹ55.6ʺ -- Debris line MR8 USACE St. Paul District

1,097.3 46°30ʹ12.8ʺ 92°41ʹ36.7ʺ Good Mud line on building BARN1 USGS

1,096.3 46°30ʹ16.3ʺ 92°41ʹ32.5ʺ -- -- MR7 USACE St. Paul District

1,094.4 46°30ʹ8.6ʺ 92°41ʹ29.2ʺ Poor Debris line in tree BARN2 USGS

1,094.0 46°30ʹ8.2ʺ 92°41ʹ28.8ʺ -- -- MR6 USACE St. Paul District

1,094.0 46°30ʹ4.8ʺ 92°41ʹ28.7ʺ Good Mud line in utility shelter BARN3 USGS

1,088.2 46°29ʹ42.2ʺ 92°41ʹ32.2ʺ -- -- MR5 USACE St. Paul District

Carlton

1,084.1 46°39ʹ47.6ʺ 92°25ʹ54.5ʺ Good Mud line on storage container CARL1 USGS

1,083.4 46°39ʹ46.1ʺ 92°25ʹ45ʺ Poor Debris line on fence CARL2 USGS

1,082.8 46°39ʹ44.7ʺ 92°25ʹ40.1ʺ Good Mud line on propane tank CARL3 USGS

1,082.7 46°39ʹ42.3ʺ 92°25ʹ29.6ʺ Good Mud line on Carlton City 

wastewater treatment plant

CARL4 USGS

1,081.9 46°39ʹ41.9ʺ 92°25ʹ25.6ʺ Good Mud line on Carlton City 

equipment garage

CARL5 USGS

1,081.7 46°39ʹ41.8ʺ 92°25ʹ23.9ʺ Good Mud line on house CARL6 USGS

1,081.7 46°39ʹ42.9ʺ 92°25ʹ22.7ʺ Good Mud line on shed CARL7 USGS

1,081.5 46°39ʹ41.9ʺ 92°25ʹ22.2ʺ Good Mud line on house CARL8 USGS

1,081.9 46°39ʹ50.1ʺ 92°25ʹ45.4ʺ Good Mud line on laundry building CARL9 USGS

1,080.8 46°39ʹ49.5ʺ 92°25ʹ35.8ʺ Good Mud line in car shop CARL10 USGS

1,081.0 46°39ʹ49.5ʺ 92°25ʹ35.8ʺ Good Mud line in car shop CARL11 USGS

1,079.7 46°39ʹ52.4ʺ 92°25ʹ38.6ʺ Good Mud line on garage CARL12 USGS

1,080.0 46°39ʹ54.8ʺ 92°25ʹ37.7ʺ Good Mud line on shed CARL13 USGS

1,079.6 46°39ʹ56.1ʺ 92°25ʹ34.1ʺ Poor Mud line on propane tank CARL14 USGS

1,080.1 46°39ʹ56.8ʺ 92°25ʹ34.6ʺ Poor Mud line on house CARL15 USGS

1,078.2 46°39ʹ57.6ʺ 92°25ʹ31.9ʺ Poor As shown by onsite person, 

line on driveway

CARL16 USGS

1,077.5 46°39ʹ58.2ʺ 92°25ʹ32.1ʺ Poor Grass line in trees CARL17 USGS

1,077.5 46°39ʹ59.9ʺ 92°25ʹ31.7ʺ Good Mud line on garage CARL18 USGS

1,076.9 46°40ʹ0.1ʺ 92°25ʹ32.2ʺ Fair Grass line on bushes CARL19 USGS

Duluth Heights, Duluth

1,320.1 46°48ʹ26.2ʹʹ 92°9ʹ57.8ʹʹ Good Mud line on building MIL1 City of Duluth; USACE Detroit District

1,320.0 46°48ʹ26ʹʹ 92°9ʹ53.2ʹʹ Poor Mud line on building MIL2 City of Duluth; USACE Detroit District

1,320.0 46°48ʹ20.1ʹʹ 92°9ʹ56.7ʹʹ Poor As shown by onsite person MIL3 City of Duluth; USACE Detroit District

1,319.9 46°48ʹ18.9ʹʹ 92°9ʹ49.3ʹʹ Fair Mud line on guard rail MIL4 City of Duluth; USACE Detroit District

1,320.4 46°48ʹ29.8ʹʹ 92°10ʹ2.1ʹʹ Fair As shown by onsite person MIL5 City of Duluth; USACE Detroit District

1,338.8 46°48ʹ45.1ʹʹ 92°10ʹ25.5ʹʹ Fair As shown by onsite person MIL6 City of Duluth; USACE Detroit District

1,337.9 46°49ʹ0.4ʹʹ 92°10ʹ32.4ʹʹ Fair As shown by onsite person MIL7 City of Duluth; USACE Detroit District

1,340.1 46°49ʹ1.9ʹʹ 92°10ʹ39.2ʹʹ Fair As shown by onsite person MIL8 City of Duluth; USACE Detroit District

1,348.3 46°49ʹ17.3ʹʹ 92°10ʹ35.4ʹʹ Fair Mud line MIL10 City of Duluth; USACE Detroit District

1,320.4 46°48ʹ30.9ʹʹ 92°9ʹ48.2ʹʹ Good Mud line in building MIL11 City of Duluth; USACE Detroit District
Appendix 1. High-Water-Mark Descriptions 21

Table 1–1. High-water-mark descriptions for the mapped communities of Barnum, Carlton, Duluth Heights neighborhood in Duluth, 

Fond du Lac neighborhood in Duluth, Moose Lake, and Thomson for the floods of June 2012 in northeastern Minnesota.—Continued

[Vertical coordinate data are referenced to the North American Vertical Datum of 1988 (NAVD 88). Horizontal coordinate data are referenced to the North 

American Datum of 1983. Approximate quality ratings of high-water marks: Excellent, plus or minus (±) 0.02 foot; Good, ± 0.05 foot; Fair, ± 0.1 foot; and Poor, 

greater than 0.10 foot (Lumia and others, 1986).°, degrees; ʹ, minutes; ʺ, seconds; --, not available; USACE, U.S. Army Corps of Engineers; USGS, U.S. Geological Survey]

Elevation 

(feet above 

NAVD 88)

Latitude Longitude High-watermark quality High-water-mark description

High-watermark 

identifier

Agency that collected data

Fond du Lac, Duluth

611.6 46°39ʹ40.5ʺ 92°17ʹ4ʺ Fair Mud line on power pole next 

to river

FDL1 USGS

608.5 46°39ʹ39.3ʺ 92°16ʹ58.6ʺ Poor Mud line on grass in park FDL2 USGS

610.2 46°39ʹ35ʺ 92°16ʹ41.4ʺ Fair Mud line on red shed FDL3 USGS

608.5 46°39ʹ35.5ʺ 92°16ʹ38.1ʺ Fair Mud line on shed FDL4 USGS

607.6 46°39ʹ36ʺ 92°16ʹ37.1ʺ Fair Grass line on garage FDL5 USGS

606.8 46°39ʹ33.5ʺ 92°16ʹ37.4ʺ Fair Mud line on shed FDL6 USGS

607.1 46°39ʹ33.8ʺ 92°16ʹ36.7ʺ Fair Mud line on shed FDL7 USGS

609.2 46°39ʹ34.7ʺ 92°16ʹ36.3ʺ Poor Grass line on fence FDL8 USGS

613.5 46°39ʹ40.3ʺ 92°16ʹ26.6ʺ Poor Grass line on fence FDL9 USGS

609.3 46°39ʹ25.4ʺ 92°16ʹ22.1ʺ Good Mud line on house FDL10 USGS

609.5 46°39ʹ16.7ʺ 92°16ʹ22.3ʺ Good Seed line on shed FDL11 USGS

609.3 46°39ʹ16.4ʺ 92°16ʹ22.1ʺ Fair Grass line on fence FDL12 USGS

608.9 46°39ʹ16.1ʺ 92°16ʹ22.1ʺ Fair Mud line on house FDL13 USGS

608.7 46°39ʹ5.6ʺ 92°16ʹ14.4ʺ Good Grass line on house FDL14 USGS

Moose Lake

1,052.5 46°27ʹ27.4ʺ 92°45ʹ4.4ʺ -- -- MR3 USACE St. Paul District

1,048.2 46°27ʹ6.2ʺ 92°44ʹ46.4ʺ Good Mud line on paved trail MOOSE1 USGS

1,049.2 46°27ʹ4.4ʺ 92°44ʹ46.3ʺ Fair Mud line on paved trail MOOSE2 USGS

1,053.3 46°27ʹ23.2ʺ 92°45ʹ24.3ʺ Poor Debris line in tree MOOSE3 USGS

1,052.8 46°27ʹ2.4ʺ 92°45ʹ34.7ʺ Good Mud line on building MOOSE4 USGS

1,052.5 46°26ʹ30ʺ 92°45ʹ40.9ʺ Good Debris line on ground MOOSE5 USGS

1,052.9 46°26ʹ46.2ʺ 92°46ʹ6.9ʺ Fair Scratch mark on bridge rail MOOSE6 USGS

1,052.9 46°26ʹ46.2ʺ 92°46ʹ6.9ʺ Fair Scratch mark on bridge rail MOOSE7 USGS

1,052.1 46°26ʹ45.7ʺ 92°46ʹ7.3ʺ -- -- MR2 USACE St. Paul District

1,050.8 46°26ʹ50.3ʺ 92°46ʹ17.2ʺ Good Mud line on building MOOSE8 USGS

1,042.9 46°26ʹ38.7ʺ 92°46ʹ34.4ʺ Poor Debris line on ground MOOSE9 USGS

Thomson

1,054.9 46°39ʹ49.7ʺ 92°23ʹ27.7ʺ Good Mud line on garage ETHOM1 USGS

1,054.9 46°39ʹ47.9ʺ 92°23ʹ26.8ʺ Good Mud line on house ETHOM2 USGS

1,072.0 46°39ʹ59.9ʺ 92°23ʹ56.6ʺ Poor Seed/Grass line on tree THOM1 USGS

1,071.0 46°39ʹ59.7ʺ 92°23ʹ57.1ʺ Poor Seed/Grass line in tree THOM2 USGS

1,064.9 46°39ʹ58.5ʺ 92°23ʹ59.8ʺ Poor Mud line behind studio THOM3 USGS

1,063.0 46°39ʹ58.4ʺ 92°23ʹ59ʺ Poor Mud line on front of studio THOM4 USGS

1,062.6 46°39ʹ58.1ʺ 92°23ʹ59.8ʺ Poor Debris line in grass THOM5 USGS

1,061.5 46°39ʹ57.4ʺ 92°23ʹ56.5ʺ Poor As shown by onsite person, on 

step next to brick planter

THOM6 USGS

1,050.5 46°39ʹ54.6ʺ 92°23ʹ57.7ʺ Poor Debris caught in fence THOM7 USGS

1,047.2 46°39ʹ52.6ʺ 92°23ʹ57.4ʺ Poor Debris line in tree THOM8 USGS

1,048.6 46°39ʹ52ʺ 92°23ʹ56.6ʺ Fair Debris line in power pole THOM9 USGS

1,046.9 46°39ʹ52.3ʺ 92°24ʹ0.1ʺ Poor Debris line at base of stake THOM10 USGS

1,046.1 46°39ʹ48.9ʺ 92°23ʹ57.6ʺ Good Mud line on pump house THOM11 USGS

1,036.0 46°39ʹ47.4ʺ 92°24ʹ0.4ʺ Poor Debris at culvert under bike 

path

THOM12 USGS

1,041.1 46°39ʹ47.2ʺ 92°23ʹ59.8ʺ Poor Debris line in trees THOM13 USGS
22 Floods of June 2012 in Northeastern Minnesota

Table 1–2. Descriptions of additional high-water marks for the floods of June 2012 in northeastern Minnesota.

[Vertical coordinate data are referenced to the North American Vertical Datum of 1988 (NAVD 88). Horizontal coordinate data are referenced to the North 

American Datum of 1983. Approximate quality ratings of high-water marks: Excellent, ± 0.02 foot; Good, ± 0.05 foot; Fair, ± 0.1 foot; and Poor, greater than 

0.10 foot (Lumia and others, 1986). °, degrees; ʹ, minutes; ʺ, seconds; USACE, U.S. Army Corps of Engineers; --, not available]

Elevation 

(feet above 

NAVD 88)

Latitude Longitude High-watermark quality High-water-mark description

High-watermark 

identifier

Agency that collected data

Keene Creek

616.7 46°43ʹ58.1ʺ 92°10ʹ5.7ʺ Good Debris line on fence KEE1 City of Duluth; USACE Detroit District

615.8 46°43ʹ56.2ʺ 92°10ʹ8.6ʺ Fair Debris line at creek KEE2 City of Duluth; USACE Detroit District

605.9 46°43ʹ58.3ʺ 92°9ʹ34ʺ Excellent Debris line on fence KEE3 City of Duluth; USACE Detroit District

614.8 46°43ʹ59.4ʺ 92°10ʹ16.6ʺ Good Mud line on building KEE5 City of Duluth; USACE Detroit District

622.5 46°44ʹ0.4ʺ 92°10ʹ21.3ʺ Good Mud line on structure KEE6 City of Duluth; USACE Detroit District

624.6 46°44ʹ1.6ʺ 92°10ʹ24.3ʺ Good Debris line on fence KEE7 City of Duluth; USACE Detroit District

654.2 46°44ʹ15.6ʺ 92°10ʹ39.4ʺ Good Debris line KEE9 City of Duluth; USACE Detroit District

651.3 46°44ʹ15.5ʺ 92°10ʹ35.1ʺ Poor Mud line on street KEE10 City of Duluth; USACE Detroit District

Kettle River

1,029.8 46°16ʹ6.1ʺ 92°51ʹ41.2ʺ -- Approximate Coordinates KR1 USACE St. Paul District

1,036.6 46°18ʹ22.5ʺ 92°51ʹ42.1ʺ -- Approximate Coordinates KR2 USACE St. Paul District

1,038.8 46°19ʹ35.6ʺ 92°50ʹ51.8ʺ -- Approximate Coordinates KR3 USACE St. Paul District

1,044.5 46°21ʹ38.9ʺ 92°50ʹ33.6ʺ -- Approximate Coordinates KR4 USACE St. Paul District

Kingsbury Creek

1,237.6 46°44ʹ37.4ʺ 92°13ʹ26.6ʺ Good As shown by onsite person KIN1 City of Duluth; USACE Detroit District

1,248.8 46°44ʹ53.9ʺ 92°13ʹ18.5ʺ Good As shown by onsite person KIN2 City of Duluth; USACE Detroit District

1,248.7 46°44ʹ52.9ʺ 92°13ʹ20.8ʺ Fair Mud line on structure. As 

shown by onsite person

KIN3 City of Duluth; USACE Detroit District

1,238.3 46°44ʹ47.6ʺ 92°13ʹ26.8ʺ Good As shown by onsite person KIN4 City of Duluth; USACE Detroit District

1,238.6 46°44ʹ49.4ʺ 92°13ʹ27ʺ Good As shown by onsite person KIN5 City of Duluth; USACE Detroit District

1,236.5 46°44ʹ44.7ʺ 92°13ʹ28.3ʺ Poor As shown by onsite person KIN6 City of Duluth; USACE Detroit District

1,238.4 46°44ʹ45ʺ 92°13ʹ26.7ʺ -- -- KIN7 City of Duluth; USACE Detroit District

1,235.2 46°44ʹ40.5ʺ 92°13ʹ42ʺ Fair As shown by onsite person KIN8 City of Duluth; USACE Detroit District

1,236.2 46°44ʹ47.6ʺ 92°13ʹ48.9ʺ Good As shown by onsite person KIN9 City of Duluth; USACE Detroit District

1,247.6 46°44ʹ56.4ʺ 92°14ʹ17.6ʺ Good As shown by onsite person KIN10 City of Duluth; USACE Detroit District

1,230.2 46°44ʹ32.1ʺ 92°13ʹ34.1ʺ Good As shown by onsite person KIN11 City of Duluth; USACE Detroit District

1,229.0 46°44ʹ25.2ʺ 92°13ʹ37.4ʺ Good As shown by onsite person KIN12 City of Duluth; USACE Detroit District

630.9 46°43ʹ31.1ʺ 92°11ʹ32ʺ Good As shown by onsite person KIN13 City of Duluth; USACE Detroit District

631.7 46°43ʹ28.4ʺ 92°11ʹ33.9ʺ Good As shown by onsite person KIN14 City of Duluth; USACE Detroit District

633.0 46°43ʹ27.1ʺ 92°11ʹ27.8ʺ Good As shown by onsite person KIN15 City of Duluth; USACE Detroit District

629.1 46°43ʹ31.3ʺ 92°11ʹ22.7ʺ Good As shown by onsite person KIN16 City of Duluth; USACE Detroit District

Miller Creek

652.6 46°45ʹ54.3ʺ 92°7ʹ59.5ʺ Good Debris line at bridge LWMIL14 City of Duluth; USACE Detroit District

652.8 46°45ʹ53.1ʺ 92°8ʹ2.1ʺ Good Debris line at bridge LWMIL15 City of Duluth; USACE Detroit District

644.1 46°45ʹ50.7ʺ 92°7ʹ57ʺ Good Mud line on building LWMIL16 City of Duluth; USACE Detroit District

640.1 46°45ʹ48.1ʺ 92°8ʹ0.5ʺ Poor As shown by onsite person LWMIL17 City of Duluth; USACE Detroit District

639.3 46°45ʹ46.3ʺ 92°7ʹ58.8ʺ Fair Mud line on post LWMIL19 City of Duluth; USACE Detroit District

Mississippi River

1,219.8 46°47ʹ31.8ʺ 93°19ʹ36.7ʺ -- -- MIS1 USACE St. Paul District

1,221.4 46°47ʹ17.8ʺ 93°19ʹ16ʺ -- -- MIS2 USACE St. Paul District

1,220.0 46°47ʹ11.1ʺ 93°19ʹ28.9ʺ -- -- MIS3 USACE St. Paul District

1,217.5 46°46ʹ13.8ʺ 93°23ʹ12.4ʺ -- -- MIS4 USACE St. Paul District

1,214.9 46°43ʹ51.9ʺ 93°26ʹ56.2ʺ -- -- MIS5 USACE St. Paul District

1,212.8 46°42ʹ39.4ʺ 93°28ʹ42.4ʺ -- -- MIS6 USACE St. Paul District

1,212.6 46°42ʹ34.9ʺ 93°29ʹ8.3ʺ -- -- MIS7 USACE St. Paul District
Appendix 1. High-Water-Mark Descriptions 23

Table 1–2. Descriptions of additional high-water marks for the floods of June 2012 in northeastern Minnesota.—Continued

[Vertical coordinate data are referenced to the North American Vertical Datum of 1988 (NAVD 88). Horizontal coordinate data are referenced to the North 

American Datum of 1983. Approximate quality ratings of high-water marks: Excellent, ± 0.02 foot; Good, ± 0.05 foot; Fair, ± 0.1 foot; and Poor, greater than 

0.10 foot (Lumia and others, 1986). °, degrees; ʹ, minutes; ʺ, seconds; USACE, U.S. Army Corps of Engineers; --, not available]

Elevation 

(feet above 

NAVD 88)

Latitude Longitude High-watermark quality High-water-mark description

High-watermark 

identifier

Agency that collected data

Mississippi River—Continued

1,210.5 46°41ʹ21.3ʺ 93°32ʹ47ʺ -- -- MIS8 USACE St. Paul District

1,209.7 46°40ʹ41.5ʺ 93°36ʹ2.8ʺ -- Overland flow crossing road 

probably from Willow River

MIS9 USACE St. Paul District

1,209.1 46°40ʹ23.2ʺ 93°36ʹ17.9ʺ -- -- MIS10 USACE St. Paul District

1,207.7 46°39ʹ6.2ʺ 93°36ʹ44.9ʺ -- -- MIS11 USACE St. Paul District

1,205.8 46°37ʹ30.5ʺ 93°38ʹ45.5ʺ -- -- MIS12 USACE St. Paul District

1,203.3 46°35ʹ23.5ʺ 93°39ʹ53.6ʺ -- -- MIS13 USACE St. Paul District

1,202.1 46°33ʹ42.6ʺ 93°41ʹ47.3ʺ -- Flood debris / silt line on tree MIS14 USACE St. Paul District

1,202.1 46°34ʹ46.8ʺ 93°42ʹ25.4ʺ -- -- MIS15 USACE St. Paul District

1,200.6 46°32ʹ47.8ʺ 93°42ʹ26.5ʺ -- -- MIS16 USACE St. Paul District

1,201.0 46°32ʹ31.7ʺ 93°42ʹ26.7ʺ -- -- MIS17 USACE St. Paul District

1,201.2 46°32ʹ28.6ʺ 93°42ʹ22.9ʺ -- -- MIS18 USACE St. Paul District

1,201.4 46°32ʹ27.2ʺ 93°42ʹ28ʺ -- -- MIS19 USACE St. Paul District

1,200.1 46°32ʹ51ʺ 93°46ʹ32.6ʺ -- -- MIS20 USACE St. Paul District

1,199.1 46°34ʹ44.1ʺ 93°47ʹ31.2ʺ -- Debris line, edge of field, right 

side of house past electric 

fence

MIS21 USACE St. Paul District

1,199.3 46°35ʹ3.3ʺ 93°48ʹ6.9ʺ -- -- MIS22 USACE St. Paul District

1,199.0 46°35ʹ6.6ʺ 93°48ʹ55.9ʺ -- -- MIS23 USACE St. Paul District

1,197.1 46°34ʹ13.8ʺ 93°52ʹ25.4ʺ -- -- MIS25 USACE St. Paul District

1,193.0 46°32ʹ38.5ʺ 93°57ʹ20.3ʺ -- -- MIS26 USACE St. Paul District

Mississippi River Diversion Channel

1,202.6 46°35ʹ23.5ʺ 93°39ʹ53.6ʺ -- -- DC1 USACE St. Paul District

1,203.0 46°35ʹ23.5ʺ 93°39ʹ53.6ʺ -- -- DC2 USACE St. Paul District

1,202.2 46°35ʹ31ʺ 93°41ʹ12.6ʺ -- -- DC3 USACE St. Paul District

1,200.1 46°35ʹ34.7ʺ 93°45ʹ38.5ʺ -- -- DC4 USACE St. Paul District

Moose Horn River

1,043.6 46°22ʹ57.5ʺ 92°50ʹ27.9ʺ -- -- MR1 USACE St. Paul District

1,044.5 46°22ʹ56.8ʺ 92°50ʹ1.7ʺ -- Approximate coordinates MR1A USACE St. Paul District

1,081.7 46°28ʹ37.7ʺ 92°42ʹ47.4ʺ -- -- MR4 USACE St. Paul District

1,113.4 46°31ʹ10.3ʺ 92°42ʹ34.3ʺ -- -- MR9 USACE St. Paul District

1,147.7 46°31ʹ9.9ʺ 92°43ʹ43ʺ -- -- MR10 USACE St. Paul District

Pine River

1,028.5 46°15ʹ17.1ʺ 92°51ʹ58.3ʺ -- Approximate coordinates PR1 USACE St. Paul District

1,033.4 46°15ʹ34.3ʺ 92°53ʹ37.8ʺ -- Approximate coordinates PR2 USACE St. Paul District

1,043.1 46°16ʹ22.1ʺ 92°54ʹ28.1ʺ -- Approximate coordinates PR3 USACE St. Paul District

1,071.6 46°18ʹ12.7ʺ 92°54ʹ28.7ʺ -- Approximate coordinates PR4 USACE St. Paul District

1,072.7 46°18ʹ36.6ʺ 92°54ʹ28.2ʺ -- Approximate coordinates. 

Water on road

PR5 USACE St. Paul District

Willow River

1,038.5 46°19ʹ24.9ʺ 92°50ʹ21.5ʺ -- Approximate coordinates WR1 USACE St. Paul District
24 Floods of June 2012 in Northeastern Minnesota
Appendix 2. Flood-Peak Inundation Maps 25

Appendix 2. Flood-Peak Inundation Maps
26 Floods of June 2012 in Northeastern Minnesota

POINT ROAD

WILLARD MU

MR8

1,099

MR8

1,099

Note: There may have been 

inundation in this area 

to an unknown depth

92°43' 92°42' 

46°31'

46°30'30"

46°30'

Aerial photograph courtesy of MNGEO, Spatial Data Portal, 2010 National Agriculture Imagery Program, 

accessed December 2012, at http://www.mngeo.state.mn.us/chouse/metadata/naip10.html

Universal Transverse Mercator projection, Zone 15

EXPLANATION

High-water mark and identifier—Number is elevation, in feet

above North American Vertical Datum of 1988 (NAVD 88)

High-water mark used in determining the elevation of floodpeak water surface?

Yes

No

Study limit

Stream centerline

Flood-inundation depth—In feet

 0.1 to 1.0

1.1 to 2.0

2.1 to 3.0

3.1 to 4.0

4.1 to 5.0

Greater than 5.0

MR7

1,096.3

Figure 2–1. Approximate extent and depth of flood-peak inundation, flood of June 2012, for the Moose Horn River at Barnum, 

Minnesota.
Appendix 2. Flood-Peak Inundation Maps 27

HIGHWAY 61 / INTERSTATE 35

FRONT STREET

MAIN STREET

WILLARD MUNGER STATE TRAIL

MR6

1,094

MR8

099

MR5

1,088.2

BARN3

1,094

MR7

1,096.3

BARN2

1,094.4

BARN1

1,097.3

MR6

1,094

MR8

099

MR5

1,088.2

BARN3

1,094

MR7

1,096.3

BARN2

1,094.4

BARN1

1,097.3

Moose Horn River

92°41'

0 0.1 0.2 0.4 MILES

0 0.1 0.2 0.4 KILOMETERS

ST. LOUIS

CASS

LAKE

ITASCA

PINE

AITKIN

COOK

CROW 

WING

CARLTON

NORTHEAST MINNESOTA

COUNTIES WITH 

DISASTER DECLARATIONS

Map location
28 Floods of June 2012 in Northeastern Minnesota

C

CARL9

1,081.9

CARL3

1,082.8

CARL2

1,083.4

CARL1

1,084.1

CAR

1,0

CARL

1,080

C

CARL9

1,081.9

CARL3

1,082.8

CARL2

1,083.4

CARL1

1,084.1

CA

1,0

CARL

1,080

Otter Creek

Aerial photograph courtesy of MNGEO, Spatial Data Portal, 2010 National Agriculture Imagery Program, 

accessed December 2012, at http://www.mngeo.state.mn.us/chouse/metadata/naip10.html

Universal Transverse Mercator projection, Zone 15

92°26'30" 92°26' 

46°40'

46°39'45"

46°39'30"

EXPLANATION

High-water mark and identifier—Number is elevation, in feet

above North American Vertical Datum of 1988 (NAVD 88)

Yes

No

Study limit

Flow continuation

Stream centerline

Flood-inundation depth—In feet

 0.1 to 1.0

1.1 to 2.0

2.1 to 3.0

3.1 to 4.0

4.1 to 5.0

Greater than 5.0

CARL1

1,084.1

High-water mark used in determining the elevation of floodpeak water surface?

Figure 2–2. Approximate extent and depth of flood-peak inundation, flood of June 2012, for Otter Creek at Carlton, Minnesota.
Appendix 2. Flood-Peak Inundation Maps 29

COUNTY ROAD 1

HIGHWAY 210

WILLARD MUNGER STATE TRAIL

CARL13

1,080

CARL11

1,081

CARL8

1,081.5

CARL7

1,081.7

CARL6

1,081.7

CARL5

1,081.9

CARL4

1,082.7

3

8

CARL19

1,076.9

CARL18

1,077.5 CARL17

1,077.5

CARL16

1,078.2

CARL14

1,079.6

CARL12

1,079.7

CARL10

1,080.8

CARL15

1,080.1

CARL13

1,080

CARL11

1,081

CARL8

1,081.5

CARL7

1,081.7

CARL6

1,081.7

CARL5

1,081.9

CARL4

1,082.7

3

8

CARL19

1,076.9

CARL18

1,077.5 CARL17

1,077.5

CARL16

1,078.2

CARL14

1,079.6

CARL12

1,079.7

CARL10

1,080.8

CARL15

1,080.1

Thomson 

Reservoir

Creek

0 0.1 0.2 0.4 MILES

0 0.1 0.2 0.4 KILOMETERS

92°25'30" 92°25'

ST. LOUIS

CASS

LAKE

ITASCA

PINE

AITKIN

COOK

CROW 

WING

CARLTON

NORTHEAST MINNESOTA

COUNTIES WITH 

DISASTER DECLARATIONS

Map location
30 Floods of June 2012 in Northeastern Minnesota

MILLER TRUNK HIGHWAY

ARROWHEAD ROAD

HAINES ROAD

MILLER TRUNK HIGHWAY

ARROWHEAD ROAD

HAINES ROAD

MILLER TRUNK HIGHWAY

ARROWHEAD ROAD

HAINES ROAD

MIL8

1,340.1

MIL7

1,337.9

M

1,

MIL10

1,348.3

MIL8

1,340.1

MIL7

1,337.9

M

1,

MIL10

1,348.3

92°11'30" 92°11' 92°10'30" 

46°49'

46°48'30"

Aerial photograph courtesy of MNGEO, Spatial Data Portal, 2010 National Agriculture Imagery Program, 

accessed December 2012, at http://www.mngeo.state.mn.us/chouse/metadata/naip10.html

Universal Transverse Mercator projection, Zone 15

EXPLANATION

High-water mark and identifier—Number is elevation, in feet

above North American Vertical Datum of 1988 (NAVD 88)

Yes

No

Study limit

Stream centerline

Flood-inundation depth—In feet

 0.1 to 1.0

1.1 to 2.0

2.1 to 3.0

3.1 to 4.0

4.1 to 5.0

Greater than 5.0

MIL1

1,320.1

High-water mark used in determining the elevation of floodpeak water surface?

Figure 2–3. Approximate extent and depth of flood-peak inundation, flood of June 2012, for Miller Creek at the Duluth Heights 

neighborhood, Duluth, Minnesota.
Appendix 2. Flood-Peak Inundation Maps 31

HAINES RO

MALL DRIVE

MAPLE GROVE ROAD

BURNING TREE ROAD

HAINES RO

MALL DRIVE

MAPLE GROVE ROAD

BURNING TREE ROAD

DECKER ROAD

MOUNTAIN SHADOW DRIVE

HAINES RO

MALL DRIVE

MAPLE GROVE ROAD

BURNING TREE ROAD

DECKER ROAD

MOUNTAIN SHADOW DRIVE

MIL3

1,320

MIL2

1,320

MIL6

1,338.8

MIL5

1,320.4

MIL4

1,319.9

MIL1

1,320.1

MIL11

1,320.4

MIL3

1,320

MIL2

1,320

MIL6

1,338.8

MIL5

1,320.4

MIL4

1,319.9

MIL1

1,320.1

MIL11

1,320.4

Miller Creek

" 92°10' 92°9'30" 92°9'

0 0.1 0.2 0.4 MILES

0 0.1 0.2 0.4 KILOMETERS

ST. LOUIS

CASS

LAKE

ITASCA

PINE

AITKIN

COOK

CROW 

WING

CARLTON

NORTHEAST MINNESOTA

COUNTIES WITH 

DISASTER DECLARATIONS

Map location
32 Floods of June 2012 in Northeastern Minnesota

W WATER STREET

3RD STREET WEST

FDL9

613.5

FDL8

609.2

FDL7

607.1

FDL6

606.8

FDL3

610.2

FDL2

608.5

FDL1

611.6

FDL14

608.7

FDL13

608.9

FDL12

609.3

FDL11

609.5

FDL10

609.3

FDL4

608.5

FDL5

607.6

FDL9

613.5

FDL8

609.2

FDL7

607.1

FDL6

606.8

FDL3

610.2

FDL4

608.5

FDL5

607.6

FDL2

608.5

FDL1

611.6

FDL14

608.7

FDL13

608.9

FDL12

609.3

FDL11

609.5

FDL10

609.3

46°39'30"

46°39'

92°17' 92°16' 

Aerial photograph courtesy of MNGEO, Spatial Data Portal, 2010 National Agriculture Imagery Program, 

accessed December 2012, at http://www.mngeo.state.mn.us/chouse/metadata/naip10.html

Universal Transverse Mercator projection, Zone 15

EXPLANATION

High-water mark and identifier—Number is elevation, in feet

above North American Vertical Datum of 1988 (NAVD 88)

Yes

No

Study limit

Stream centerline

Flood-inundation depth—In feet

 0.1 to 1.0

1.1 to 2.0

2.1 to 3.0

3.1 to 4.0

4.1 to 5.0

Greater than 5.0

FDL1

611.6

High-water mark used in determining the elevation of floodpeak water surface?

Figure 2–4. Approximate extent and depth of flood-peak inundation, flood of June 2012, for the St. Louis River at the Fond du 

Lac neighborhood, Duluth, Minnesota.
Appendix 2. Flood-Peak Inundation Maps 33

HIGHWAY 23

St. Louis River

92°15'

0 0.1 0.2 0.4 MILES

0 0.1 0.2 0.4 KILOMETERS

ST. LOUIS

CASS

LAKE

ITASCA

PINE

AITKIN

COOK

CROW 

WING

CARLTON

NORTHEAST MINNESOTA

COUNTIES WITH 

DISASTER DECLARATIONS

Map location
34 Floods of June 2012 in Northeastern Minnesota

HIGHWAY 61

NORTH RIVERSIDE DRIVE

MR2

1,052.1

MOOSE9

1,042.9

MOOSE8

1,050.8

MOOSE7

1,052.9

MOOSE6

1,052.9

MOOSE5

1,052.5

MOOSE4

1,052.8

MOOSE3

1,053.3

MR2

1,052.1

MOOSE9

1,042.9

MOOSE8

1,050.8

MOOSE7

1,052.9

MOOSE6

1,052.9

MOOSE5

1,052.5

MOOSE4

1,052.8

MOOSE3

1,053.3

Moose Horn River

Moosehead Lake

92°46' 

46°27'30"

46°27'

46°26'30"

Aerial photograph courtesy of MNGEO, Spatial Data Portal, 2010 National Agriculture Imagery Program, 

accessed December 2012, at http://www.mngeo.state.mn.us/chouse/metadata/naip10.html

Universal Transverse Mercator projection, Zone 15

EXPLANATION

High-water mark and identifier—Number is elevation, in feet

above North American Vertical Datum of 1988 (NAVD 88)

Yes

No

Study limit

Stream centerline

Flood-inundation depth—In feet

 0.1 to 1.0

1.1 to 2.0

2.1 to 3.0

3.1 to 4.0

4.1 to 5.0

Greater than 5.0

MOOSE9

1,042.9

High-water mark used in determining the elevation of floodpeak water surface?

Figure 2–5. Approximate extent and depth of flood-peak inundation, flood of June 2012, for the Moose Horn River and 

Moosehead Lake at Moose Lake, Minnesota.
Appendix 2. Flood-Peak Inundation Maps 35

INTERSTATE 35

HIGHWAY 27

MR3

1,052.5

MOOSE2

1,049.2

MOOSE1

1,048.2

MR3

1,052.5

MOOSE2

1,049.2

MOOSE1

1,048.2

Portage River

92°45' 92°44'

0 0.1 0.2 0.4 MILES

0 0.1 0.2 0.4 KILOMETERS

ST. LOUIS

CASS

LAKE

ITASCA

PINE

AITKIN

COOK

CROW 

WING

CARLTON

NORTHEAST MINNESOTA

COUNTIES WITH 

DISASTER DECLARATIONS

Map location
36 Floods of June 2012 in Northeastern Minnesota

HIGHWAY 210

DALLES AVENUE

VERMILLION STREET

THOM4

1,063

THOM2

1,071

THOM1

1,072

THOM12

1,036

THOM9

1,048.6

THOM8

1,047.2

THOM7

1,050.5

THOM6

1,061.5

THOM5

1,062.6

THOM3

1,064.9

THOM13

1,041.1

THOM11

1,046.1

THOM10

1,046.9

THOM4

1,063

THOM2

1,071

THOM1

1,072

THOM12

1,036

THOM9

1,048.6

THOM8

1,047.2

THOM7

1,050.5

THOM6

1,061.5

THOM5

1,062.6

THOM3

1,064.9

THOM13

1,041.1

THOM11

1,046.1

THOM10

1,046.9

St. Louis River

Thomson Reservoir

Aerial photograph courtesy of MNGEO, Spatial Data Portal, 2010 National Agriculture Imagery Program, 

accessed December 2012, at http://www.mngeo.state.mn.us/chouse/metadata/naip10.html

Universal Transverse Mercator projection, Zone 15

92°24'15" 92°24' 

46°40'15"

46°40'

46°39'45"

ST. LOUIS

CASS

LAKE

ITASCA

PINE

AITKIN

COOK

CROW 

WING

CARLTON

NORTHEAST MINNESOTA

COUNTIES WITH 

DISASTER DECLARATIONS

Map location

Figure 2–6. Approximate extent and depth of flood-peak inundation, flood of June 2012, for the Thomson Reservoir outflow 

near the St. Louis River at Thomson, Minnesota.
Appendix 2. Flood-Peak Inundation Maps 37

COUNTY ROAD 1

NUE

ETHOM2

1,054.9

ETHOM1

1,054.9

ETHOM2

1,054.9

ETHOM1

1,054.9

Diversion canal

voir

0 0.05 0.1 0.2 MILES

0 0.05 0.1 0.2 KILOMETERS

92°23'45" 92°23'30" 92°23'15"

EXPLANATION

High-water mark and identifier—Number is elevation, in feet

above North American Vertical Datum of 1988 (NAVD 88)

Yes

No

Study limit

Stream centerline

Flood-inundation depth—In feet

 0.1 to 1.0

1.1 to 2.0

2.1 to 3.0

3.1 to 4.0

4.1 to 5.0

Greater than 5.0

THOM1

1,072

High-water mark used in determining the elevation of floodpeak water surface?
38 Floods of June 2012 in Northeastern Minnesota
Appendix 3. Flood-Peak Water-Surface Profiles 39

Appendix 3. Flood-Peak Water-Surface Profiles
40 Floods of June 2012 in Northeastern Minnesota

MR8

BARN1

MR7

BARN2

MR6

BARN3

MR5

Willard Munger State Trail

Front Street

Main Street

Interstate 35

1,085

1,090

1,095

1,100

0 0.5 1.0 1.5 2.0 2.5

Elevation, in feet above the North American Vertical Datum of 1988

Distance downstream along stream centerline, in miles

Figure 3–1. Flood-peak water-surface profile with selected high-water marks for the Moose 

Horn River at Barnum, Minnesota, for the flood of June 2012.

CARL1

CARL2

CARL3

CARL4 CARL5

CARL6

CARL8

CARL9

CARL11

CARL10

CARL13

CARL18

Willard MungerState TrailCounty Road 1

1,076

1,078

1,080

1,082

1,084

1,086

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8

Distance downstream along stream centerline, in miles

Profile along overflow

north through town

Elevation, in feet above the North American Vertical Datum of 1988

Figure 3–2. Flood-peak water-surface profile with selected high-water marks for Otter 

Creek at Carlton, Minnesota, for the flood of June 2012.
Appendix 3. Flood-Peak Water-Surface Profiles 41

MIL10

MIL8

MIL6

Inferred 

elevation

MIL11 MIL1

MIL3

MIL4

Miller Trunk Highway

Miller Trunk Highway

Haines Road

Burning Tree Road

Miller Trunk HighwayMaple Grove Road / County Highway 6Mountain Shadow DriveMall DriveDecker Road

1,315

1,320

1,325

1,330

1,335

1,340

1,345

1,350

0 0.5 1.0 1.5 2.0

Distance downstream along stream centerline, in miles

Elevation, in feet above the North American Vertical Datum of 1988

Figure 3–3. Flood-peak water-surface profile with selected high-water marks for Miller Creek 

at the Duluth Heights neighborhood, Duluth, Minnesota, for the flood of June 2012.

FDL1

FDL3

FDL10

Average of FDL11, FDL12,

and FDL13 

FDL14

3rd Street West/Highway 23

606

608

610

612

614

0 0.5 1.0 1.5 2.0 2.5 3.0

Distance downstream along stream centerline, in miles

Inferred elevations

Elevation, in feet above the North American Vertical Datum of 1988

Figure 3–4. Flood-peak water-surface profile with selected high-water marks for the St. Louis 

River at the Fond du Lac neighborhood, Duluth, Minnesota, for the flood of June 2012.
42 Floods of June 2012 in Northeastern Minnesota

MR3 MOOSE5

Average of MOOSE6,

MOOSE7, and MR2

MOOSE8

MOOSE9

Highway 27

Highway 61

North Riverside Road

1,040

1,045

1,050

1,055

0 0.5 1.0 1.5 2.0 2.5

Distance downstream along stream centerline, in miles

Elevation, in feet above the North American Vertical Datum of 1988

Figure 3–5. Flood-peak water-surface profile with selected high-water marks for the Moose 

Horn River and Moosehead Lake at Moose Lake, Minnesota, for the flood of June 2012.

THOM1

THOM2

THOM3

THOM4

THOM5

THOM6

THOM7

THOM8 THOM10 THOM11

THOM13

Dam

1,035

1,040

1,045

1,050

1,055

1,060

1,065

1,070

1,075

0 0.1 0.2 0.3

Distance downstream along stream centerline, in miles

Elevation, in feet above the North American Vertical Datum of 1988

Figure 3–6. Flood-peak water-surface profile with selected high-water marks for the 

Thomson Reservoir outflow near the St. Louis River at Thomson, Minnesota, for the flood of 

June 2012.
Appendix 3. Flood-Peak Water-Surface Profiles 43

Publishing support provided by: 

Rolla Publishing Service Center

For more information concerning this publication, contact: 

Director, USGS Minnesota Water Science Center 

2280 Woodale Drive 

Mounds View, Minnesota 55112 

(763) 783–3100

Or visit the Minnesota Water Science Center Web site at: 

http://mn.water.usgs.gov/
Czuba and others— Floods of June 2012 in Northeastern Minnesota—Scientific Investigations Report 2012–5283