Present-day Lake Erie is the product of at least two extensive glacial events which occurred during the Quaternary Epoch, the last of which retreated from the Great Lakes between 9,000 and 11,000 years ago (For a detailed description of glacial events see Dreimanis and Karrow 1972; Karrow 1989; Karrow and Calkin 1985; Coakley 1985). Lake Erie is the shallowest of the Great Lakes, has the shortest water retention time, lowest volume, the second highest human population living along its shores, after Lake Michigan, (Table 2.1), and contains more than one third of the wetlands in the Great Lakes system (IJC 1989; Stenson 1993). Lake Erie also differs from the other Great Lakes in that its coast is dominated by sedimentary material left by retreating glaciers (high bluffs, low bluffs, beaches and dune complexes), rather than rock (Stenson 1993). This high shoreline availability of glacial till, strong winds and the associated currents that they produce, and long (variations in climate), medium (seasonal hydrological cycle) and short-term (wind set-up and seiches) variations in Lake Erie water depth have resulted in the north shore of Lake Erie being the most active section of the Great Lakes shoreline. It is this shoreline activity that over the last 4,000 years created and continues to shape Long Point, the largest sandy peninsula or sand spit on the Great Lakes.
| Lake | Superior | Michigan | Huron | Erie | Ontario |
|---|---|---|---|---|---|
| Elevation (m asl) | 183 | 176 | 176 | 173 | 74 |
| Average depth (m) | 1,145 | 199 | 76 | 21 | 91 |
| Maximum depth (m) | 307 | 265 | 223 | 60 | 225 |
| Retention Time (yr) | 191 | 99 | 22 | 2.6 | 6 |
| Lake volume (km3) | 12,100 | 4,920 | 3,540 | 485 | 1,640 |
| Surface area (kmē) | 82,100 | 57,800 | 59,600 | 25,700 | 18,960 |
| Drainage area (kmē) | 127,700 | 118,000 | 134,100 | 78,000 | 64,030 |
| Shoreline length (km) | 4,385 | 2,633 | 6,157 | 1,402 | 1,146 |
| Population (US & Can) | 738,540 | 13,970,900 | 2,372,119 | 12,968,606 | 6,642,175 |