# 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 about 2.6 years on average, the shortest retention time of the five.

URL: https://lakeerie.info/facts/how-much-water-is-in-lake-erie · Facts as of 2026-08-28 · Checked 2026-10-04

## Key numbers

| Measure | Value | Source |
|---|---|---|
| Volume | 116 mi³ / 484 km³ | U.S. Environmental Protection Agency |
| Retention time | 2.6 years | U.S. Environmental Protection Agency |
| Inflow from the Detroit River | 80% | U.S. Environmental Protection Agency |
| People drinking Lake Erie water | about 11 million people | U.S. Environmental Protection Agency |

## The smallest Great Lake by volume

For all its surface area, Lake Erie holds the least water of the Great Lakes because it is so shallow. The EPA puts its volume at 116 mi³ (484 km³).[1] Lake Ontario, smaller on the map, holds 393 mi³; Lake Huron 850 mi³; Lake Michigan 1,180 mi³; and Lake Superior 2,900 mi³.[1] The volumes are measured at low water, so the lake holds a little more when levels are high. In everyday units the EPA's figure works out to about 128 trillion U.S. gallons; that is our conversion, not a separate measurement.

| Lake | Volume |
|---|---|
| Superior | 2,900 mi³ (12,100 km³) |
| Michigan | 1,180 mi³ (4,920 km³) |
| Huron | 850 mi³ (3,540 km³) |
| Erie | 116 mi³ (484 km³) |
| Ontario | 393 mi³ (1,640 km³) |

## How fast the water turns over

Retention time is the EPA's measure of how long water stays in a lake, based on its volume and the average rate at which water flows out. For Lake Erie it is about 2.6 years.[2] The other lakes hold their water far longer: about 6 years for Ontario, 22 years for Huron, 99 years for Michigan and 191 years for Superior.[1] Quick turnover helps when inputs fall: the EPA credits joint U.S. and Canadian limits on phosphorus, agreed in the late 1960s, with lowering open-lake phosphorus levels.[2]

## Where it comes from, who drinks it

About 80% of Lake Erie's inflow arrives through the Detroit River, carrying water from the upper Great Lakes; precipitation adds 11% and the lake's own tributaries 9%.[2] The lake is the drinking-water source for about 11 million people, and the EPA warns that excessive algal growth threatens both the lake's ecosystem and human health.[2]

## Levels rise and fall

The amount of water in the lake is not fixed. In 1911 the Encyclopaedia Britannica described a yearly swing in level of between nine inches and two feet, with the low in February and the high in midsummer, and noted that strong westerly gales could lower the west end by 7 to 8 ft while raising the east end by 5 to 8 ft.[3] Those wind-driven surges are seiches, explained on their own page.

## Questions people ask

**Which Great Lake has the least water?**

Lake Erie, with about 116 mi³ (484 km³), according to the EPA's table of Great Lakes physical features.

**How long does water stay in Lake Erie?**

About 2.6 years on average, the shortest retention time of the five Great Lakes, according to the EPA.

## Sources

1. Physical Features of the Great Lakes, U.S. Environmental Protection Agency. https://www.epa.gov/greatlakes/physical-features-great-lakes (accessed 2026-10-04)
2. Lake Erie | US EPA, U.S. Environmental Protection Agency. https://www.epa.gov/greatlakes/lake-erie (accessed 2026-10-04)
3. Encyclopaedia Britannica, 11th edition (1911), "Erie (lake)", Encyclopaedia Britannica, 11th edition (1911), via Wikisource. https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Erie,_Lake (accessed 2026-10-04)

## How to cite

Lake Erie Gazetteer, How much water is in Lake Erie?, lakeerie.info/facts/how-much-water-is-in-lake-erie, accessed October 19, 2026.

Lake Erie Gazetteer is an independent reference operated by WeldonPC. Not affiliated with or endorsed by any government agency, lake or historical society, museum, Ohio Sea Grant, Lake Erie Waterkeeper, the U.S. Lighthouse Society or Lake Erie Shores & Islands.