NARROWSBURG, NY — A new map, which reveals the mysterious contours of the Big Eddy Narrows as the deepest and narrowest points on the 330-mile Delaware River, is available as an 11-inch-by-17-inch poster. The poster was donated by its creator to benefit the nonprofit Upper Delaware Council (UDC).

Lisa Glover of Honesdale, PA converted her curiosity over Narrowsburg’s bathymetric claim to fame into creativity after discovering that the “Mighty D” runs 113 feet deep at River Mile 290. 

The tiny Town of Tusten hamlet of Narrowsburg derived its name from its other distinction—it is also the main stem’s narrowest part, coursing through a rock canyon that is only 200 feet wide.

For comparison, the Delaware River’s average depth is four to five feet (although holes of 12-18 feet aren’t uncommon) and its width varies from nine to 35 miles.

Glover, who enjoys paddle boarding, holds a bachelor’s degree in architecture and a master’s degree in engineering from Lehigh University. She also writes a blog called Lisa the Maker.

Glover consulted with the UDC after becoming fascinated by those Narrowsburg facts.

A historic marker at the Big Eddy Observation Deck offers two theories of how the 113-foot-deep hole was created: 1) it is a long-drowned “plunge pool” from a glacial waterfall or 2) it is a pothole that tumbling rocks scoured out through erosion, according to HMdb.org. The Big Eddy, where the deepest point lurks downstream from the narrows, often has a visible whirlpool.

Glover read articles from the UDC’s “The Upper Delaware” newsletter, which pointed her to interviews with National Park Service divers who had measured the hole, to various illustrations, and which called for an accurately detailed map of the river bottom to potentially solve the mystery. While topographic maps exist to show the elevation of landforms above sea level, bathymetric maps show depths of landforms below water.

Glover’s research extended to the U.S. Geological Survey (USGS) from a citation in the Summer 1993 newsletter article.

Glover discovered that the agency had published a USGS LiDAR scan of the Delaware River in 2020 and tracked down research scientist John Young, who provided a digital map focused on the Big Eddy section.

Gathering all her resources, Glover designed a topobathymetric color map with 10-foot contour lines and to-scale cross sections of The Narrows and The Deeps, printed 50 copies, and generously offered a stack to the UDC to share with the public as a fundraiser.

Glover posted a story with more details at www.lisathemaker.com/post/uncovering-the-contours-of-the-deeps. That blog post also cites her affiliations with Highlights for Children, the Stourbridge Project, the Wayne County Arts Alliance and the Center on Rural Innovation, for which she is their Placemaking fellow.

To request a Big Eddy Narrows poster for a $20 donation to the UDC, email administrative support staff member Stephanie Driscoll at stephanie@upperdelawarecouncil.org, call 845/252-3022 or stop by the council’s office on weekdays at 211 Bridge St.—next to the firehouse—for pick-up.

The supply of maps is limited. Payment must be by check or cash. Add $3 for mail order.

Contributed by the Upper Delaware Council.