St. Clair River

The St. Clair River (French: Rivière Sainte-Claire) is a 40.5-mile-long (65.2 km)[1] river in central North America which drains Lake Huron into Lake St. Clair, forming part of the international boundary between the Canadian province of Ontario and the U.S. state of Michigan. The river is a significant component in the Great Lakes Waterway, with shipping channels permitting cargo vessels to travel between the upper and lower Great Lakes.

Saint Clair River
Rivière Sainte-Claire
Lake st clair landsat.jpeg
Landsat satellite photo, showing Lake Saint Clair (center), as well as St. Clair River connecting it to Lake Huron (to the North) and Detroit River connecting it to Lake Erie (to the South)
Physical characteristics
 - locationLake Huron
 - location
Lake St. Clair
Length40.5 mi (65.2 km)
Basin size223,600 sq mi (579,000 km2)
 - average182,000 cu ft/s (5,200 m3/s)
Navigation on St Clair River
Great Lakes freighters navigating on the lower St. Clair River. View is from the U.S. side, looking across to Canada.


The river, which some consider a strait,[2] flows in a southerly direction, connecting the southern end of Lake Huron to the northern end of Lake St. Clair. It branches into several channels near its mouth at Lake St. Clair, creating a broad delta region known as the St. Clair Flats.


The river is 40.5 miles (65.2 km) long[1] and drops 5 feet (2 m) in elevation from Lake Huron to Lake St. Clair. The flow rate averages around 182,000 cubic feet per second (5,200 m3/s), and the drainage area is 223,600 square miles (579,000 km2).[3] This takes into account the combined drainage areas of Lakes Huron, Michigan, and Superior.


In the 18th century, French voyageurs and coureurs des bois travelled on the river to trade with Native Americans and transport furs in canoes to major posts of French and British traders, including Fort Detroit, built downriver in 1701. European demand for American furs, especially beaver, was high until the 1830s.

Ships built at Marine City, Michigan, during the mid-19th century carried immigrants up the river on their way to new homes in the American West. Lumber harvested on The Thumb of Michigan was shipped downriver as log rafts to Detroit.

In the early 20th century, lake steamers carried passengers and traveled among the small towns along the St. Clair and Detroit rivers, and around the Great Lakes. During the 20th century, freighters traveled throughout the Great Lakes transporting commodities such as iron ore from the Mesabi Range, copper, and grain, all products of settlers' labor. Iron was taken to Ashtabula, Ohio and other industrial cities for processing and steel manufacture, and grain was often shipped through to major eastern markets such as Cleveland and New York City.


Blue Water Bridge
Head of river looking into Lake Huron, showing the twin Blue Water Bridge

The St. Clair River and its Lambton County tributaries in Ontario contributes 103,210 acres (41,770 ha) to the watershed, although this does not include the Sydenham River watershed. In Michigan, the Black River, Pine River, and Belle River drain 780,600 acres (315,900 ha) in Lapeer, Macomb, Sanilac, and St. Clair counties; the watersheds around Bunce Creek and Marine City are relatively small.


Land usage

Detroit, USA Taken From Windsor, Canada
Detroit skyline can be seen from across the river (Windsor, Canada)

Most of the watershed away from the river in Ontario and Michigan is used for agriculture. There were numerous sugar beet farms in the flatlands, and an annual beet market was held in Marine City, Michigan, for years at harvest time. Many of the 19th-century English immigrants to this area came from Lincolnshire, England, where sugar beets have been a major commodity crop.

A few forest and wetland areas have survived, although their area has declined significantly since European settlement, clearing and development of cultivated fields for various agricultural crops.

Much of the shoreline on both sides of the St. Clair River is urbanized and heavily industrialized. Intensive development has occurred in and near the adjacent cities of Port Huron, Michigan and Sarnia, Ontario, at the northern end of the river. The heaviest concentration of industry, including a large petrochemical complex, lies along the Ontario shore south of Sarnia.

Several communities along the St. Clair rely on the river as their primary source of drinking water. About one-third to one-half of the residents of Michigan receive their water from the St. Clair/Detroit River waterway. Industries including petroleum refineries, chemical manufacturers, paper mills, salt producers and electric power plants also need high-quality water for their operations. Since the late 20th century and passage of environmental laws to protect air and water quality, there have still been events when some of these industries have illegally contaminated river waters after discharging pollutants. Major clean-up activities were required.

Land habitat

Land areas of the St. Clair River shoreline and flats consist of two biological zones: upland and transitional, both of which are normally above the water table, but which may be flooded periodically.

The upland forests consist of deciduous species, many of which are near their northern climatic limit. Most pre-European settlement trees have been cleared for agriculture, industry, or urbanization. Remaining forest stands, such as oak savannas as well as lakeplain prairies, are found along the southern reaches of the river, particularly on the islands of the St. Clair River Delta and on the Michigan shore in Algonac State Park.

Transitional species are abundant in the low-lying regions, categorized as shrub ecotones, wet meadows, sedge marshes, and island shorelines and beaches. This habitat is home to water and land mammals, including humans, as well as songbirds, waterfowl, insects, pollinators, reptiles, and amphibians.

Water habitat

The aquatic habitat of the St. Clair River ranges from deep and fast near the Blue Water Bridge to shallow and slow in the lower river near its discharge point into Lake St. Clair.

Each area provides a unique habitat for aquatic life:

Area of concern

Algorail in (St Clair River Mich)
Canadian freighter Algorail downbound in the St. Clair River

The St. Clair River is listed as an Area of Concern (AOC) because of pollutants such as bacteria, heavy metals, and toxic organics, which had come from municipal and industrial discharges, urban and rural runoff, combined sewer overflows (CSOs), and contaminated sediments.

The St. Clair River AOC includes the entire river, from the Blue Water Bridge at the north end, to the southern tip of Seaway Island, west to St. Johns Marsh and east to include the north shore of Mitchells Bay on Lake St. Clair. Anchor Bay is not included.

Through the Great Lakes Agreement, a Remedial Action Plan (RAP) was created to initiate cleanup measures. Its background report noted the adverse effects of pollution in the river and lakes:

  • Restrictions on fish consumption
  • Bird and animal deformities
  • Degradation of benthos
  • Restrictions on dredging activities
  • Restrictions on drinking water consumption
  • Beach closings
  • Degradation of aesthetics
  • Added cost to agriculture and industry
  • Loss of fish and wildlife habitat

The RAP for the St. Clair River AOC was initiated in 1985. A bi-national group, called the RAP Team, was established in 1987 to develop the plan and ensure adequate and appropriate public involvement. The RAP Team included representatives from federal, state, and provincial governments of both Canada and the United States.

  • A large blob of perchloroethylene was found at the bottom of the St Clair River due to runoff from Dow Chemical Corp in 1985. It remains there, slowly mixing with the water.[5]

Erosion and Great Lakes drainage

Federal officials have long acknowledged that dredging and riverbed mining in the St. Clair dropped the long-term average of Great Lakes Huron and Michigan by about 16 inches. A bi-national Great Lakes water-level study concluded in 2013 that unexpected erosion since the last major St. Clair dredging project in the early 1960s has dropped the lakes' long-term average by an additional 3 to 5 inches. Today, these lakes are nearly 2 feet lower than before human modifications to the riverbed of the St. Clair River. This record low has raised concerns about the long-term health of the lakes. Activists urge remediation to slow the flow of waters through the St. Clair River and out of the lake system, to restore former water levels.[6]


This is a list of bridges and other crossings of the St. Clair River from Lake St. Clair upstream to Lake Huron.

Crossing Carries Location Coordinates
Walpole Island Bridge County Road 32 Chatham-Kent Municipality and Walpole Island, Ontario (Crosses the Chenal Ecarte of the St. Clair) 42°35′34.4″N 82°28′27.7″W / 42.592889°N 82.474361°W
Harsens Island Ferry Cars and passengers Algonac, Michigan and Harsens Island, Michigan (crosses the North Channel of the St. Clair) 42°36′57.4″N 82°33′38.9″W / 42.615944°N 82.560806°W
Russell Island Ferry Passengers only Algonac, Michigan and Russell Island, Michigan 42°37′07.2″N 82°31′47.9″W / 42.618667°N 82.529972°W
Walpole-Algonac Ferry Cars and passengers Algonac, Michigan and Walpole Island, Ontario 42°37′01.6″N 82°31′17.6″W / 42.617111°N 82.521556°W
Sombra-Marine City (Bluewater) Ferry Cars and passengers Marine City, Michigan and Sombra, Ontario 42°42′46.4″N 82°29′13.3″W / 42.712889°N 82.487028°W
St. Clair Tunnel Canadian National Railway Port Huron, Michigan and Sarnia, Ontario 42°57′34.2″N 82°25′19.0″W / 42.959500°N 82.421944°W
Blue Water Bridge I-94 / I-69
Highway 402
42°59′55.1″N 82°25′23.9″W / 42.998639°N 82.423306°W

See also


  1. ^ a b U.S. Geological Survey. National Hydrography Dataset high-resolution flowline data. The National Map, accessed November 7, 2011
  2. ^ Eckel, Patricia M. (May 4, 2005). "Some Thoughts on Isostatic Rebound as a Hypothetical Factor in Lake and Strait Characteristics in the Great Lakes". Niagara Issues. Missouri Botanical Garden. Retrieved April 9, 2015.
  3. ^ "Great Lakes Factsheet No. 1". United States EPA. Retrieved 30 May 2013.
  4. ^ "About nin.da.waab.jig", Walpole Island Heritage Centre, accessed 8 August 2014
  5. ^
  6. ^ Dan Egan, "Lakes Michigan, Huron hit record low water level", Milwaukee Journal-Sentinel Online, 3 February 2013

External links

Coordinates: 42°31′59″N 82°40′29″W / 42.53306°N 82.67472°W

Algonac, Michigan

Algonac is a city in St. Clair County of the U.S. state of Michigan. The population was 4,110 at the 2010 census.

Algonac is located at the southern end of the St. Clair River, just before it splits into a large delta region known as the St. Clair Flats. (Coordinates 42.6°N 82.56°W / 42.6; -82.56) The St. Clair River drains Lake Huron into Lake St. Clair and is part of the Great Lakes Waterway.

At the center of Algonac is Algonac City Park, a park which contains a half-mile long boardwalk along the St. Clair River. Just to the north of the city is Algonac State Park.

Algonac was the birthplace of Emily Helen Butterfield, an artist and the first woman to be licensed as an architect in Michigan. She was famous for innovations in church architecture. It was the home of Chris-Craft boat company; the maker of the first mass-produced speed boats. It was also the home of Gar Wood, the first great speed boat racer.

Algonac State Park

Algonac State Park is a public recreation area covering 1,450 acres (590 ha) along the St. Clair River, two miles north of the city of Algonac in St. Clair County, Michigan. The state park's half mile of river frontage offers a view of passing international freighters.

Blue Water Bridge

The Blue Water Bridge is a twin-span international bridge across the St. Clair River that links Port Huron, Michigan, United States, and Sarnia, Ontario, Canada. The Blue Water Bridge connects Highway 402 in Ontario with both Interstate 69 (I-69) and Interstate 94 (I-94) in Michigan.

Fontana (Schooner)

The Fontana was a wooden schooner that sank in the St. Clair River in U.S. state of Michigan on 3 August 1900 while under tow from the SS Kaliyuga.

On the morning of 4 August 1900, the Fontana, under tow from the SS Kaliyuga, collided with the Santiago, in tow of the SS Appomattox. John McGregor was sleeping in the Fontana's forecastle and was killed when the ships collided.Days after the collision, the Schooner Kingfisher collided with the wreck of the Fontana.

No company was willing to bid to raise the Fontana, on account of the swift current and difficulty in patching the hold in her hull. She was blasted with dynamite in October 1900 as the United States government believed that a further accident involving the Fontana could obstruct the St. Clair river.

Fort Gratiot Light

Fort Gratiot Light, the first lighthouse in the state of Michigan, was constructed north of Fort Gratiot in 1829 by Lucius Lyon, who later became one of Michigan's first U.S. Senators.The Fort Gratiot Light marks the entrance to the St. Clair River from Lake Huron (going south) in the southern portion of Michigan's Thumb. The light is still active and the grounds are an active Coast Guard facility, but it has recently been handed over to the Port Huron Museum. It is the oldest surviving lighthouse in Michigan. There is also a public beach and park on the property, known as Lighthouse Beach.

It is across the river from Point Edward Front Range Light.

Great Lakes Waterway

The Great Lakes Waterway (GLW) is a system of natural channels and canals which enable navigation between the North American Great Lakes. Though all of the lakes are naturally connected as a chain, water travel between the lakes was impeded for centuries by obstacles such as Niagara Falls and the rapids of the St. Marys River.

Its principal civil engineering works are the Welland Canal between Lakes Ontario and Erie, and the huge Soo Locks between Huron and Superior. Dredged channels were constructed in the St. Marys River, the Detroit River, Lake St. Clair and the St. Clair River between Huron and Erie. Usually, one or more U.S. Coast Guard icebreakers help keep the water passage open for part of the fall and early winter, although shipping usually ceases for two to three months thereafter. The St. Lawrence Seaway allows navigable shipping from the GLW to the Atlantic Ocean, while the Illinois Waterway extends commercial shipping to the Mississippi River and the Gulf of Mexico. The Great Lakes Waterway is co-administered by the governments of Canada and the United States of America.

Harsens Island

Harsens Island is a wet marshy location at the mouth of the St. Clair River on Lake St. Clair, in the U.S. state of Michigan. Politically, the island is in Clay Township of St. Clair County.

Lake Huron

Lake Huron is one of the five Great Lakes of North America. Hydrologically, it comprises the easterly portion of Lake Michigan–Huron, having the same surface elevation as its westerly counterpart, to which it is connected by the 5-mile-wide (8.0 km), 20-fathom-deep (120 ft; 37 m) Straits of Mackinac. It is shared on the north and east by the Canadian province of Ontario and on the south and west by the state of Michigan in the United States. The name of the lake is derived from early French explorers who named it for the Huron people inhabiting the region.

The Huronian glaciation was named due to evidence collected from Lake Huron region. The northern parts of the lake include the North Channel and Georgian Bay. Across the lake to the southwest is Saginaw Bay. The main inlet is the St. Marys River, and the main outlet is the St. Clair River.

Lake St. Clair

Lake St. Clair (French: Lac Sainte-Claire) is a freshwater lake that lies between the Canadian province of Ontario and the U.S. state of Michigan. It was named after Clare of Assisi, on whose feast day it was navigated and christened by French Catholic explorers in 1679. It is part of the Great Lakes system, and along with the St. Clair River and Detroit River, Lake St. Clair connects Lake Huron (to its north) with Lake Erie (to its south). It has a total surface area of about 430 square miles (1,100 km2) and an average depth of just 11 feet (3.4 m); to ensure an uninterrupted waterway, government agencies in both countries have maintained a deep shipping channel through the shallow lake for more than a century.

Lambton County

Lambton County is a county in Southwestern Ontario, Canada. It is bordered on the north by Lake Huron, which is drained by the St. Clair River, the county's western border and part of the Canada-United States border. To the south is Lake Saint Clair and Chatham-Kent, another county in Ontario. Lambton County's northeastern border follows the Ausable River and Parkhill Creek north until it reaches Lake Huron at the beach community of Grand Bend. The county seat is in the Town of Plympton-Wyoming.

The largest city in Lambton County is Sarnia, which is located at the mouth of the St. Clair River. The two Blue Water Bridges cross the river at Sarnia, connecting it to Port Huron, Michigan. The bridges are one of the busiest border crossings between the two countries. The river is also traversed by two passenger ferries further south, and a rail tunnel, also at Sarnia, runs underneath it. The CN rail tunnel accommodates double stacked rail cars. Along with Sarnia, the population centres in Lambton County are: Corunna, Petrolia, Grand Bend, Wyoming, Forest, and Watford.

Lambton County started as a part of the District of Hesse. The district of Hesse included British territories west of Long Point (practically all of western Ontario). The district was later divided and renamed using English district names (Essex, Suffolk, Kent, etc.). Lambton was part of Kent county. In 1849 districts were abolished and the County of Lambton was formed. Lambton and Kent first shared the capital city of Sandwich (since renamed as Windsor, Ontario). In 1852 the partnership was dissolved and Lambton become a full county. It is named in honour of John Lambton, 1st Earl of Durham, who visited the area in the late 1830s.


Lambton—Kent was a federal electoral district in Ontario, Canada, that was represented in the House of Commons of Canada from 1935 to 1979. This riding was created in 1933 from parts of Kent, Lambton East and Lambton West ridings.

It was initially defined as consisting of:

the part of the county of Lambton contained in the townships of Brooke, Dawn, Enniskillen, Euphemia, Sombra, and Warwick, including the town of Forest, Walpole Island, St. Ann Island and the other islands at the mouth of the St. Clair River; and

the part of the county of Kent contained in the townships of the Gore of Chatham, Gore of Camden, Camden and Zone.In 1947, it was redefined to exclude the village of Arkona (Lambton County); and the townships of Gore of Camden (Kent County).

In 1966, it was defined to consist of:

the part of the County of Kent contained in the Townships of Camden, Chatham, Dover, Harwich, Howard, Orford and Zone;

the part of the County of Lambton contained in the Townships of Brooke, Dawn, Euphemia, Enniskillen and Sombra;

Walpole Island Indian Reserve No. 46.The electoral district was abolished in 1976 when it was redistributed between Essex—Kent, Kent and Lambton—Middlesex ridings.

Marysville, Michigan

Marysville is a city in St. Clair County of the U.S. state of Michigan. The population was 9,959 at the 2010 census. The municipality was founded in 1919, first as a village, then became a city in 1924.

Marysville is located on the western shore of the St. Clair River, across from Corunna, Ontario. The city is marked by winding streets, subdivisions, a riverfront boardwalk, and an industrial park. The city was home to the former Wills Sainte Claire Automotive company, a Morton Salt plant, and Detroit Edison's Marysville Power Plant.

Michigan Air Line Railroad

The Michigan Air Line Railroad was a planned railroad across southern Michigan, connecting the Canada Southern Railway to Chicago, Illinois. Only part of the line was built, and it was split between the Michigan Central Railroad (part of the New York Central Railroad, which also acquired the Canada Southern Railway) and the Grand Trunk Railway.

Port Huron, Michigan

Port Huron is a city in the U.S. state of Michigan and the county seat of St. Clair County. The population was 30,184 at the 2010 census. The city is adjacent to Port Huron Township but is administratively autonomous.

Located along the St. Clair River, it is connected to Point Edward, Ontario in Canada via the Blue Water Bridge. The city lies at the southern end of Lake Huron and is the easternmost point on land in Michigan. Port Huron is home to two paper mills, Mueller Brass, and many businesses related to tourism and the automotive industry. The city features a historic downtown area, boardwalk, marina, museum, lighthouse, and the McMorran Place arena and entertainment complex.


Sarnia is a city in Southwestern Ontario, Canada, and had a 2016 population of 71,594. It is the largest city on Lake Huron and in Lambton County. Sarnia is located on the eastern bank of the junction between the Upper and Lower Great Lakes where Lake Huron flows into the St. Clair River, which forms the Canada–United States border, directly across from Port Huron, Michigan. The city's natural harbour first attracted the French explorer La Salle, who named the site "The Rapids" when he had horses and men pull his 45-ton barque Le Griffon up the almost four-knot current of the St. Clair River on 23 August 1679.This was the first time anything other than a canoe or other oar-powered vessel had sailed into Lake Huron, and La Salle's voyage was thus germinal in the development of commercial shipping on the Great Lakes. Located in the natural harbour, the Sarnia port remains an important centre for lake freighters and oceangoing ships carrying cargoes of grain and petroleum products. The natural port and the salt caverns that exist in the surrounding areas, together with the oil discovered in nearby Oil Springs in 1858 led to the massive growth of the petroleum industry in this area. Because Oil Springs was the first place in Canada and North America to drill commercially for oil, the knowledge that was acquired there led to oil drillers from Sarnia travelling the world teaching other nations how to drill for oil.The complex of refining and chemical companies is called Chemical Valley and located south of downtown Sarnia. While in 2011 the city had the highest level of particulates air pollution of any Canadian city, it has since dropped down to 30th. About 60 percent of the particulate matter, however, comes from the neighboring United States. Lake Huron is cooler than the air in summer and warmer than the air in winter; therefore, it moderates Sarnia's humid continental climate, which makes temperature extremes of hot and cold less evident. In the winter, Sarnia occasionally experiences lake-effect snow from Arctic air blowing across the warmer waters of Lake Huron and condensing to form snow squalls once over land.Culturally, Sarnia is a large part of the artistic presence in Southern Ontario. The city's International Symphony Orchestra is renowned in the area and has won the Outstanding Community Orchestra Award given by the Detroit Music Awards in 2011. Michael Learned graced the stage of the Imperial Theatre for a 2010 production of Driving Miss Daisy.

St. Clair, Michigan

St. Clair is a city in St. Clair County in the eastern "Thumb" of the U.S. state of Michigan. The population was 5,485 at the 2010 census. The city is located on the St. Clair River near the southeast corner of St. Clair Township.

St. Clair County, Michigan

St. Clair County is a county located in the U.S. state of Michigan bordering the west bank of the St. Clair River. As of the 2010 census, the population was 163,040. It is the 13th-most populous county in the state. The county seat is Port Huron, located at the north end of the St. Clair River at Lake Huron. The county was created September 10, 1820, and its government was organized in 1821.Located northeast of Detroit, St. Clair County is part of the Detroit-Warren-Dearborn, MI Metropolitan Statistical Area. Geographically, it lies in the Thumb area of eastern Michigan.

St. Clair Tunnel

The St. Clair Tunnel is the name for two separate rail tunnels which were built under the St. Clair River between Sarnia, Ontario and Port Huron, Michigan. It was the first full-size subaqueous tunnel built in North America. (By full-size it is meant that it allowed a railroad to run through it.) It is a National Historic Landmark of the United States, and has been designated a civil engineering landmark by both US and Canadian engineering bodies.

Walpole Island First Nation

Walpole Island is an island and First Nation reserve in southwestern Ontario, Canada, on the border between Ontario and Michigan in the United States. It is located in the mouth of the St. Clair River on Lake St. Clair, about 121 kilometres (75 mi) by road from Windsor, Ontario and 124 kilometres (77 mi) from Detroit, Michigan.It is unceded territory and is inhabited by the Ojibwe, Potawatomi, and Odawa peoples of the Walpole Island First Nation, who call it Bkejwanong, meaning "where the waters divide" in Anishinaabemowin. In addition to Walpole Island, the reserve includes Squirrel Island, St. Anne Island, Seaway Island, Bassett Island, and Potawatomi Island. The river or creeks that separate these islands provide the area with its other commonly used name,

Swejwanong or "many forks of a river."It is independent of, but within the geographic region of Lambton County and adjoins the municipality of Chatham-Kent and the township of St. Clair. Across the St. Clair River to the west are the United States city of Algonac, Michigan, and Clay Township. Harsen's Island, also unceded Anishinaabe territory, is now on the west side of the international border line. The border was redrawn in the 19th century following disputes between the United Kingdom and the United States; their governments were oblivious to the interests and rights of the Indigenous peoples living on and using these lands. As such, the First Nation is now trying to solve their grievances with the Crown with a specific claim.

Walpole Island is known as the resting place of Tecumseh, prominent 19th-century leader of the Native American tribe known as the Shawnee.

Great Lakes of North America
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