Fonferek’s Glen & Falls Truly a Geological Gem!
Nestled in an unassuming location on former agricultural land, nearly abutting a housing subdivision in the Town of Ledgeview south of Green Bay, lies a surprising natural gem. On a somewhat muggy Saturday mid-morning, June 23rd, 15 Ledge Tour participants ventured out and were treated to a professionally guided geological journey through Fonferek’s Glen. Our knowledgeable guide was Dr. John Luczaj, UW-Green Bay Geology Professor, and we were joined by one of his former professors, Dr. William Mode of UW-Oshkosh. Access to the area was made available by the Fonferek family initially when the park was created and has been planted with native trees and prairie.
Leading up to the tour, getting background information proved uninspiring and scant. If you believe the brief info on Brown County websites related to the Falls, you might not want to delve beyond its unassuming description: “This waterfall rarely has a lot of water and is often no more than a trickle. It is the first of the Lake Michigan waterfalls north of Chicago.” And, a second website about the Glen mentions this 74-acre ‘geological gem’ features “a 30’ waterfall, limestone (John corrects as ‘dolomite,’ a most common misnomer) cliffs and stone archway located along Bower Creek in the Town of Ledgeview,” along with some basic geological facts.
Again, these descriptions belie the visceral experience of being there, climbing gingerly down loose rocky debris to the creek bottom and slowly wending our way along it to view its walls flanking the Creek up close and personal, and ultimately seeing its famous natural arch from the bottom and top of the Glen. All along the way, John filled us with a sense of the underlying geological history and its relationship to the surrounding landscape.
Even the alleged cause of the stone archway is suspect and mysterious, attributed to a cow’s misstep causing her to fall into the undercut part of the glen. John debunks the popular myth, explaining that the water level at the time of the arch’s creation and nature of the underlying rock strata make that impossible.
To understand more about this special feature, he puts it all into geological perspective with the rest of the Niagara escarpment in Brown County, sharing information from the Fall 2010 Great Lakes SEPM/Tri-State Geological Conference Field Trip Guidebook. “Generally, the escarpment is a straight, northeast-trending cliff throughout most of (the county). However, in the Town of Ledgeview at Scray Hill, (it) takes a dramatic turn and is oriented nearly east-west,” he explained. “More significantly, the escarpment is completely concealed between here and the UW-Green Bay campus, about seven miles to the north! As a result, the east-west portion of the Niagara escarpment near Fonferek’s Glen is one of the few, if not the only, portions that is controlled by faults over its entire length in Wisconsin. Erosion along the region’s faults has produced a southeast-oriented buried bedrock valley extending several miles to the east of our present location.”
The area is underlain by the Ordovician Maquoketa Formation, John added, with an abrupt contact between the two strata. “Slightly more than a foot of a green, pyrite-rich dolomite is preserved here in the upper portion of the Maquoketa. While small patches of soft-green mudstone (which we got to handle – it’s pliable and sticky) are occasionally exposed in the creek bed base, most of the Maquoketa is covered here by talus and alluvium.”
When we scaled back up to the top of the Glen by the main entrance and went to revisit the waterfall, we had a delightful surprise. At the beginning of our journey some two hours earlier, the falls was scarcely a trickle. Suddenly, it was as if someone had turned on the faucet full blast, with the water cascading fully over the rock steps, catching and reflecting sunlight, filling our ears with that unmistakable sound of rushing water. The timing couldn’t have been more perfect; the lower water allowed us to traverse the creek bed the entire journey and stay dry.
We all agreed our adventure was well worth the cost of admission and a few slips and scrapes. For more information about upcoming Ledge Tours that benefit LNRP and our partnering program, the Niagara Escarpment Resource Network, check our websites and watch for announcements.