GREECE, N.Y. (WROC) — Just how high is the water on the Great Lakes?

That’s the question trying to be answered along the shoreline in Wayne County today, and the answer is more important than you think.

Updating the lake level is key for forecasts related to flooding along the lake shore, as well as making sure shipping through the complicated lock system that connects the lakes.

“The lakes where they interact there’s always a big difference and so they want to have accurate information between the two different lakes and how they’re how much water they have to have in a lock to get a certain size ship through,” said Jim Harrington a cartographer with the National Geodetic Survey.

A survey like this is done every 25 to 35 years to account for changes in the shoreline and in the basins of the lakes themselves. The Great Lakes originated as a result of the glacial retreat during the last ice age. As the glaciers moved north, they carved the lakes out and filled them initially with meltwater from the retreating ice. The lakes are still reeling from that impact.

“Northern great lakes have what we call glacial rebound, it’s where the ground is actually rising, and there’s parts maybe in the lower lakes where it’s starting to subside,” said Harrington.

In the end, the data collected in the survey serves one purpose, helping us to better understand and monitor one of our most important natural resources.