What’s the Difference?
Lakes, Ponds and Wetlands

Although lakes, ponds, and wetlands may have similar characteristics, they are actually very different from one another, with unique ecosystem structure and function. Factors to consider when identifying these bodies of water include water depth, surface area, percentage of emerging plant cover, and the slope of the banks. Together, these factors determine plant and animal life living in the area, as well as water quality.

Water Depth + Bank Slope
Wetlands are quite shallow, averaging less than 3 feet in depth, with gentle, gradually sloped banks. Ponds average 4 to 8 feet deep, with steeper bank slopes. Lakes are typically the deepest of the three.

Surface Area
Lakes, ponds, and wetlands can each cover a range of sizes. Ponds range from <1 to 12 acres in surface area. Wetlands can also be <1 acre in size, but some are as large as hundreds of acres. Lakes are typically the largest, covering hundreds (and sometimes thousands) of acres.

Emerging Plant Cover
Because of their shallow depth, wetlands tend to have abundant emerging vegetation. Wetlands are defined by having 30% or more emerging plant cover, like cattails or bulrush, as compared to ponds which have less than 30%.

In addition to visible factors that help determine types of water bodies, there are invisible factors at play such as water quality. Water in wetlands tends to be lower in nitrate than lakes and ponds due to the microbial process of denitrification, where nitrate is converted to nitrogen gas, removing nitrogen from the water and improving water quality. Because wetlands provide the ideal environment for denitrification, wetlands are a highly effective conservation tool. Depending on landscape position and design, some wetlands also allow for soil particles in water to settle out, also aiding in cleaner water.