Great Lakes Water Levels

What are the factors that influence Great Lakes water levels?

What is the “normal” range of Great Lakes water levels?

What about Lakes Michigan-Huron?

Environmental and Socio-Economic Impacts

Climate Variability and the future…

Water levels go up, water levels go down….

Great Lakes Cross Section

Lake Erie

Lakes Michigan

and Huron

St. Lawrence River

Niagara Falls

804 ft

752 ft 925 ft

1333 ft

Lake

St. Clair

212 ft

379 60 223 89 236 150 77 350 33 52 28 35

Distance in Miles

571.0 ft 579.3 ft 601.0 ft

245.4 ft

20.6 ft

Great Lakes Basin Framework Study

Lake Superior

Lake Ontario

What Drives Water Level Change?

Climate Precipitation + Runoff – Evaporation = NBS

Seasonal changes in climate (annual)

Inflows and Outflows Connecting Channel Flows between Lakes

Water-Level Regulation

Diversions (into and out of basin)

Consumptive Uses

Wind and Storm Events (short term)

Great Lakes Water

Balance

Lake water levels are climatically

driven by seasonal changes in

precipitation and evaporation.

Evaporation is affected by surface

water temperature, wind speed, and

presence/absence of ice cover.

Inflows/outflows via connecting

channels between Lakes

St. Marys River

St. Clair/Detroit River

Niagara River

St. Lawrence River

Source: Great Lakes Environmental Research Laboratory

Month

mm

on

th

e L

ak

e S

urfa

ce

-100

-50

0

50

100

150

200

250

Net Basin Supply (P + R - E)

Jan Mar May Jul Sept Nov Feb Apr Jun Aug Oct Dec

Month

mm

on

th

e L

ak

e S

urfa

ce

-200

-100

0

100

200

300

Runoff Precip Evap

Jan Mar May Jul Sept Nov Feb Apr Jun Aug Oct Dec

Hydrological Components

Lake Superior

Hydrologic Values

1948-2006

Courtesy IUGLS

Long Lac/ Ogoki

154 m3/s (5400 cfs).

Chicago Diversion

91 m3/s (3,200 cfs)

Lake Michigan-

Huron

Lake Erie

56% precipitation

40% runoff

4% diversions

----------------------

43% evaporation

57% outflow

39% precipitation

34% runoff

27% inflow

----------------------

31% evaporation

68% outflow

1% Chicago diversion

79% inflow

11% precipitation

10% runoff

----------------------

89% outflow

11% evaporation

Lake Superior

Lake Ontario

79% inflow

15% runoff

6% precipitation

----------------------

93% outflow

7% evaporation St. Marys River

2110 m3/s

St. Clair/Detroit River

5360 m3/s

Niagara River

5780 m3/s

St. Lawrence

7060 m3/s

Diversions and Impacts

Lake Superior Great Lakes

Courtesy IUGLS

Long Lac/ Ogoki

154 m3/s (5,400 cfs).

Chicago Diversion

91 m3/s (3,200 cfs)

Welland Canal

244 m3/s (8620 cfs)

+9 cm (+3.5”)

0

0

Net +9 cm (+3.5”)

+7 cm (+2.8”)

-4 cm (-1.6”)

-12 cm (-4.7”)

Net -9 cm (-3.5”)

+11 cm (+4.3”)

-6 cm (-2.4”)

-4 cm (-1.6”)

Net +1 cm (+0.4”)

Lake Michigan-

Huron

Lake Erie

Connecting Channel

Diversion in

Diversion out

Diversion within

St. Clair River

Sault St. Marie

Control Structures

Cornwall Massena

Control Structures

Basinwide Drop in

GL Water Levels Lake Ontario

Regulation Begins

August 2013 Forecast

Low Water Impacts

Environmental

Shifts in shoreline position/location (loss/gain wetlands)

Loss of hydraulic connectivity (Georgian Bay wetlands/tributaries)

Changes in seasonal magnitude, timing and duration

Altered tributary flows and Lake circulation patterns

Degradation of water quality

Socio-Economic

Commercial Shipping

Recreational Boating/Marina Operation

Coastal hazards (erosion and flooding)

Public Health and Safety (water quality)

Property Access

Glacial Isostatic Adjustment

Glacial Isostatic Adjustment (GIA) in northern Lake Huron and Lake

Superior exacerbates impact of low Lake Michigan-Huron water

levels. Rates are cm/100 years relative to Lake outlet elevations.

IUGLS - Lake Michigan-Huron Water Levels

Long-term change in the head

between Lakes Michigan-Huron and

Lake Erie.

Possible erosion/increased

conveyance in St. Clair River due to

dredging and sand mining?

1962 last time major dredging

occurred on St. Clair River

(subsequent maintenance dredging

lower reaches only).

No compensation for St. Clair River

dredging (25 and 27 ft channels).

Level Rationale

0 cm (0.0”) No change

10 cm (3.9”) Post 1962 dredging

25 cm (9.8”) Plus 27-ft channel (1959-1962)

40 cm (15.7”) Plus 1930 mining & 25-ft channel

50 cm (19.7”) All alterations since 1850

Restoration Scenarios

8

2

1 5A

IJC Recommendations - St. Clair River

Recommends further investigation to restore Lake

Michigan-Huron water levels

Recommends that the governments undertake further

investigation of options to increase water levels in Lakes

Michigan-Huron by 13 to 25 cm (about 5 to 10 inches).

Investigation to be funded, undertaken, and concluded as quickly

as possible.

Criteria and Deliverables

Explore options that would provide relief during low water

periods, but not exacerbate future high water levels, and

Provide a comprehensive binational benefit-cost analysis and a

detailed environmental impact study of potential structural

options.

IJC Recommendations - Lake Superior

IJC Endorses Lake Superior Regulation Plan 2012.

Plan 2012 delivers robust performance over a wide range of

possible hydrologic conditions.

Preparing supplemental Orders of Approval to implement Plan

Further study of Multi-Lake Regulation is not warranted.

Climate uncertainties, high cost, institutional requirements, and

environmental concerns.

1973 Regulation of Great Lakes Water Levels and 1993 IJC

Levels Reference Study reached similar conclusions.

IJC Recommendations - Multi-Lake Regulation

IJC Recommendations - Adaptive Management

Endorses implementation of a comprehensive Adaptive

Management approach supported by Science and

Monitoring

Established International Great Lakes – St. Lawrence River

Adaptive Management Task Team to further develop a detailed

adaptive management plan.

Strengthening hydroclimate monitoring and modeling;

Ongoing risk assessment;

Ensuring more comprehensive information management and outreach;

Improving tools and processes for decision makers;

Collaborative regional adaptive management study for addressing water

level extremes; and

Integration of water quality and quantity modeling activities.

Climate Variability and Water Levels

According to the most recent climate models, the climate

in the upper Great Lakes basin during the next 30-70

years is likely to be characterized by:

Increase in storm severity - an increase in precipitation and more

frequent and intense storms (weather variability);

Increase in evaporation - an increase in lake evaporation

resulting from higher surface water temperatures and wind

speeds, lack of winter ice;

Change in seasonal timing - increased water supply during

winter/spring months accompanied by larger decreases in

supply during summer/early fall resulting in slight overall annual

declines.

Future Great Lakes Water Levels

Great Lakes water levels are anticipated to remain below long-term historic mean water levels, but generally within the range of historic water levels. Anticipate more extreme and variable water level events, i.e.

anticipate both low and high water level regimes that may exceed historic thresholds, both low and high.

Lower Lake Michigan-Huron water levels may continue to occur irrespective of St. Clair River compensation. St. Clair River compensation may reduce, but not eliminate potential low water-level impacts on Lakes Michigan-Huron.

Adaptive management is still required to plan for (and respond to) extreme water level events whether or not St. Clair River compensation is implemented.

Questions?

Late Holocene Lake Levels - Lakes

Michigan/Huron

Historicalrecord

Historical average(1819 - 1999)

Nipissing IIphase

Algomaphase

v. 2003

MeasuredInferred

1800 2000

177

178

~160-year fluctuation

~30-year fluctuation

0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000

Calendar year before 1950

175.0

175.5

176.0

176.5

177.0

177.5

178.0

178.5

179.0

179.5

180.0

180.5

181.0

574

576

578

580

582

584

586

588

590

592

594

1950 1500 1000 500 0 500 1000 1500 2000 2500 3000AD BC

YearCourtesy Todd A. Thompson - Indiana Geological Survey

August 2013 Forecast

Lake Superior Water Level Regulation

Sabin Rule (1916-1941)

Rule P-5 (1941-1951)

Rule of 1949 (1951-1955)

1955 Modified Rule of 1949

(1955-1979)

SO-901 (“Guide” 1973-

1979)

Plan 1977 (1979-1990)

Plan 1977A (1990-present)

Plan 2012 proposed…

181.5

182.0

182.5

183.0

183.5

184.0

184.5

1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

Wat

er

Leve

l (m

, IG

LD 8

5) Lake Superior Level

Pre-Project

Plan 77A

175.0

175.5

176.0

176.5

177.0

177.5

178.0

1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

Wat

er

Leve

l (m

, IG

LD 8

5) Lake Michigan-Huron Level

Plan 77A and PreProject

St. Clair River Restoration