Lake Erie facts, answered with sources

Short answers to the questions people ask most about Lake Erie, each with the number, its source and the date it was published or computed. The same figures appear everywhere on the site, from one registry, so they never disagree.

Lake Erie by the numbers

Every figure links to its source below. Units in U.S. and metric.
Measure	Value
Water area	9,910 sq mi^[1] (25,700 km²)
Length	241 mi^[2] (388 km)
Greatest breadth	57 mi^[2] (92 km)
Average depth	62 ft^[1] (19 m)
Maximum depth (EPA)	210 ft^[1] (64 m)
Maximum depth (NOAA bathymetry)	63 m^[3] (about 207 ft)
Volume	116 mi³^[1] (484 km³)
Shoreline, including islands	871 mi^[1] (1,402 km)
Land drainage area	30,140 sq mi^[1] (78,000 km²)
Elevation (1995 atlas)	569 ft^[2] (173 m)
Retention time	2.6 years^[1]
Inflow from the Detroit River	80%^[4]
People living in the watershed	approximately 12 million people^[4]
People drinking Lake Erie water	about 11 million people^[4]
Islands	31^[5]
Warmest month, August (1995–2025 lake-wide mean)	74.8 °F^[6] (23.8 °C^[7])
Coldest month, February (1995–2025 lake-wide mean)	33.1 °F^[6] (0.6 °C^[7])
Average annual maximum ice cover, 1973–2026	80.5%^[8]
Lowest annual maximum ice cover (1998)	5.4%^[8]
Lighthouses in this gazetteer	45^[9]

lake-erie-facts.csv (free, CC BY 4.0) · More on these numbers

Size and depth

How deep is Lake Erie? Lake Erie averages 62 ft (19 m) deep. Its deepest point, in the eastern basin, reaches 210 ft (64 m), according to the U.S. EPA; NOAA's…
How big is Lake Erie? Lake Erie covers 9,910 sq mi (25,700 km²) of water, according to the U.S. EPA. The EPA's 1995 Great Lakes Atlas gives its length as 241 mi…
How much water is in Lake Erie? Lake Erie holds about 116 mi³ (484 km³) of water, the least of the five Great Lakes, according to the U.S. EPA. Its water is replaced in…
Is Lake Erie the shallowest Great Lake? Yes. Lake Erie's average depth is 62 ft (19 m). The next shallowest, Lake Huron, averages 195 ft (59 m), and Lake Superior 483 ft (147 m)…
How does Lake Erie compare with the other Great Lakes? Lake Erie is the fourth-largest Great Lake by area, 9,910 sq mi (25,700 km²), but the smallest by volume, 116 mi³ (484 km³), and the…
Lake Erie by the numbers Lake Erie covers 9,910 sq mi (25,700 km²), averages 62 ft (19 m) deep, reaches 210 ft (64 m) at its deepest and holds 116 mi³ (484 km³) of…

Water and weather

Lake Erie water temperature by month Averaged across the lake from 1995 to 2025, Lake Erie's surface is warmest in August, about 74.8 °F (23.8 °C), and coldest in February…
Does Lake Erie freeze over? Most winters, largely. NOAA GLERL records show Lake Erie's maximum ice cover averaged 80.5% over 54 winters from 1973 to 2026, reaching…
What is a seiche? A seiche (said 'saysh') is a standing wave that sloshes back and forth across an enclosed body of water, usually after strong winds or a…
What causes algal blooms in Lake Erie? Mostly too many nutrients, above all phosphorus. Runoff from farms and cities feeds algae and cyanobacteria in Lake Erie's warm, shallow…
Is it safe to swim in Lake Erie? It depends on the beach and the day. State and provincial health departments test Lake Erie beaches for bacteria and post advisories…

Places and names

Which states and provinces border Lake Erie? Lake Erie borders four U.S. states, Michigan, Ohio, Pennsylvania and New York, and one Canadian province, Ontario, which holds the whole…
How many islands are in Lake Erie? Lake Erie has 31 islands, 18 in the United States and 13 in Canada, mostly in the western basin, according to Wikipedia. The largest is…
How did Lake Erie form? Glaciers carved it. NOAA's study of the lake floor says repeated advances of ice scoured the basin out of soft bedrock 1–2 million years…
Where does the name Lake Erie come from? Lake Erie is named for the Erie, an Iroquoian people who lived south of the lake in the 1600s. The Smithsonian's Handbook of American…

Ships and lights

How many shipwrecks are in Lake Erie? No one knows exactly. Estimates cited by Wikipedia range from about 1,400 to 8,000 wrecks, of which about 270 have confirmed locations…
The largest and deadliest Lake Erie shipwrecks Lake Erie's deadliest wrecks were crowded passenger steamers: the G.P. Griffith, which burned in 1850 with 241 to 289 lost; the Erie…
How many lighthouses are on Lake Erie? This gazetteer counts 45 lighthouses on Lake Erie's shores and islands, standing, ruined or relocated: 29 in the United States and 16 in…
Which Lake Erie lighthouses can you climb? As of October 2026, 10 Lake Erie lighthouses have offered tower climbs, usually seasonally, according to their operators: five in Ohio…
What is the oldest lighthouse on Lake Erie? The Marblehead Lighthouse in Ohio, built in 1821 and first lit in 1822, is the oldest Lake Erie lighthouse still standing; Wikipedia and…

Charts you can use

Lake Erie water temperature by month Average lake-wide surface temperature for each month, 1995–2025, from NOAA GLERL.
Lake Erie ice cover by winter, 1973–2026 The largest share of the lake frozen in each winter, from NOAA GLERL.
Lake Erie depth by basin, west to east Average and maximum depth of the western, central and eastern basins, from the U.S. EPA.
Lake Erie shipwreck timeline The documented wrecks in this gazetteer, by decade of loss.

Sources

Physical Features of the Great Lakes, U.S. Environmental Protection Agency. Accessed 2026-10-04.
The Great Lakes: An Environmental Atlas and Resource Book, 3rd edition (1995), Factsheet No. 1, U.S. Environmental Protection Agency and Government of Canada. Accessed 2026-10-04.
Bathymetry of Lake Erie and Lake Saint Clair: Lake Erie and Lake Saint Clair Geomorphology, NOAA National Centers for Environmental Information (NGDC). Accessed 2026-10-04. Values computed by us from this data.
Lake Erie | US EPA, U.S. Environmental Protection Agency. Accessed 2026-10-04.
Lake Erie, Wikipedia. Accessed 2026-10-04.
GLSEA lake-average daily surface water temperature, Lake Erie, 1995-present (degrees F, all_year_glsea_avg_e_F.csv), NOAA Great Lakes Environmental Research Laboratory. Accessed 2026-10-04. Values computed by us from this data.
GLSEA lake-average daily surface water temperature, Lake Erie, 1995-present (degrees C, all_year_glsea_avg_e_C.csv), NOAA Great Lakes Environmental Research Laboratory. Accessed 2026-10-04. Values computed by us from this data.
Great Lakes Ice Cover: annual maximum ice cover and dates (dates_AMIC.txt), NOAA Great Lakes Environmental Research Laboratory. Accessed 2026-10-04. Values computed by us from this data.
Lake Erie Gazetteer data: this site's own compiled records (lighthouses, shipwrecks, storms), Lake Erie Gazetteer (WeldonPC). Accessed 2026-10-04. Values computed by us from this data.