A Brief History of Human Land Use in the Lehigh Gap

One of only five major water gaps bisecting the 250-mile-long Kittatinny Ridge, the Lehigh Gap was formed by the erosive forces of the Lehigh River. Throughout its history, the Gap has served as a vital transportation corridor for people and wildlife alike. Human habitation of the Gap occurred as early as 13,000 years ago when Native American hunter-gatherers began following migrating mammals (including elk, bison, and wooly mammoths) northward as the Laurentide Ice Sheet receded. The Lenape People hunted, fished, gathered, and farmed in the vicinity of the Lehigh Gap for generations thereafter. On the crest of the Kittatinny Ridge, a vast savanna – one of Pennsylvania’s last remaining original grasslands – marks the location where Indigenous People used prescribed fire to manage the ecosystem for farming and hunting over thousands of years. Before it was a bustling highway, the road now known as Route 248 was a major Native American pathway called the Nescopeck Path.

A new era of human history in the Lehigh Gap began in 1737, when the Walking Purchase opened the region to settlement by European immigrants. As in earlier years, human habitation at this time was directly influenced by the topography, ecology, and geology of the Lehigh Gap. The lower fertile slopes around the Gap were cleared mainly for agricultural use. Meanwhile, the abundant forests on the steep Kittatinny Ridge provided important natural resources that supported the earliest industrial activity of the region. Pines were logged for ship building, hemlock and oak bark was harvested to tan leather, and other trees were burned to produce charcoal fuel for the burgeoning iron industry. In addition, crushed sandstone harvested from the Kittatinny was used as a natural pigment in paints produced in Lehigh Gap area paint mills (one of which was located near LGNC’s headquarters on present-day Paint Mill Road).

The discovery of anthracite coal north and west of the Lehigh Gap area in the late 18^th century secured the Lehigh Gap’s place in history. The Kittatinny was a sizeable barrier between the Pennsylvania coal fields and the industrial centers of the Mid-Atlantic and New England regions. Since the Lehigh Gap and Schuylkill Gap were the only natural passageways between the mines and the factories, both played a defining role in American industrialization. The Lehigh Gap quickly became an epicenter of coal transportation – first by raft, then by canal (beginning in 1829), and finally by railroad. Of the four rail lines that once passed through the Gap, one remains today.

In 1898, a notable business – the New Jersey Zinc Company – made the economic decision to move closer to the coal fields in order to enhance the efficiency of its operations. Established in Sussex County, New Jersey around 1850, the New Jersey Zinc Company specialized in smelting zinc for use in a wide array of products, ranging from galvanized steel to paint. Upon building a new, state-of-the-art factory immediately northwest of the Lehigh Gap, the company planned and built the Borough of Palmerton to provide residence for its diverse work force. The New Jersey Zinc Company was in operation for over 80 years, offering equitable employment (even in the midst of the Great Depression) and supporting a thriving community that, to this day, represents the quintessential American ‘small town.’

Though the New Jersey Zinc Company was ahead of its time socially and economically, the factory operated at a time when pollution control and monitoring was not a priority. Not only was industrial pollution unregulated for the better part of the company’s history, but the technology to mitigate pollution had not been well developed until recent decades. Moreover, no one at that time understood the short or long-term impacts of pollution on the environment or human health. For these reasons – which were beyond the control of the New Jersey Zinc Company – emissions from the company’s plants impacted the surrounding landscape.

After about 80 years of heavy metal deposition (no mining occurred here) and 65 years of acid rain, approximately 3,000 acres of land were barren and laden with toxic zinc, cadmium, and lead. As a result, in 1983, the EPA ‘quarantined’ the impacted area by establishing one of the nation’s first Superfund sites – known as the Palmerton Zinc Pile Superfund site – under the newly enacted Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). According to this law, the responsible polluter is required to remediate the impacted area. Although various methods of large-scale ecological restoration have been employed since the 1990s, LGNC took a novel approach by revegetating with native prairie grasses. This effort has successfully restored ecological function and beauty to a once-barren ‘moonscape.’

History of Lehigh Gap Nature Center

The establishment of the first and only nature center on a Superfund site and the intense restoration work that followed was – both literally and figuratively speaking – a grassroots effort. The Lehigh Gap Nature Center was born out of the efforts of a small group of volunteers who recognized the value and potential of the area. Perhaps the Nature Center’s earliest origins can be traced to the late Grant White, who was quoted in a 1960s-era newspaper article as saying there ought to be a nature center in the Lehigh Gap. The late Donald S. Heintzelman, through his hawk watching efforts at Bake Oven Knob (which also date back to the 1960s), established a community of people concerned about wildlife and founded the Wildlife Information Center (WIC) in 1986.

WIC is the official 501(c)(3) nonprofit corporation through which LGNC still does business today. In the mid-1990s, WIC had an office in downtown Slatington but sought a property upon which it could build an environmental education center. Its members were looking at small farm properties in the northern Lehigh County area when White (a WIC Board member) suggested the group consider locating its future nature center at the Lehigh Gap. An old farmhouse in the Lehigh Gap was a wonderful prospect, given its proximity to the Lehigh River and Kittatinny Ridge and with a pond on site.

LGNC’s first Executive Director, Dan Kunkle (then the president of the WIC Board of Directors), recalls that, upon visiting the site in April 2002 to inquire if the property might someday be for sale, the owners acted as if WIC’s arrival was divine providence; the people had just listed their home for sale on the internet. While touring the grounds, the group sighted an Osprey overhead, which served as the inspiration for the name that house bears today – the Osprey House. The house and surrounding 14 acres were purchased, and WIC moved its headquarters to the Osprey House in December 2002.

Two more properties (300 and 442 acres, respectively) adjoining the first were purchased over the next twelve months, and the Lehigh Gap Wildlife Refuge was created. The Osprey House served as the headquarters for the Refuge, which was opened to the public in May of 2003. Early on, LGNC established a tradition of working through partnerships by collaborating with organizations like the Delaware & Lehigh (D&L) National Heritage Corridor and the Pennsylvania Department of Conservation & Natural Resources, whose guidance and funding made the purchase of our properties possible. As an environmental education program began to evolve on the site, the Wildlife Information Center soon registered an official “doing business as” name with the state and began operating at Lehigh Gap Nature Center.

Approximately 400 acres of our property falls within the Palmerton Zinc Pile Superfund site and was heavily contaminated with toxic zinc, cadmium, and lead between 1898 and 1980, during the period of operation of the New Jersey Zinc Company. Following the advice of U.S Department of Agriculture scientist John Dickerson and former D&L Trail Manager Bill Mineo, we planted native prairie grasses to remediate the site. In 2003, we established 56 one-acre experimental test plots to determine which combination of grass seed and soil amendments (fertilizer, crushed limestone, and compost) would grow most successfully on the barren mountainside. Once the proper mix was ascertained, about a quarter-inch of soil amendment mixed with seed was spread on the lower elevations of the mountain. Despite the skepticism of some restoration experts, the seeds germinated and established the beginnings of a grassland within the first year. Dead for decades, the mountain was finally green again. The steep, barren upper slopes of the Ridge were seeded with crop dusters beginning in 2006.

LGNC’s mix of 12 native prairie grass species has done far more than simply revegetate the mountain. Having evolved in this region of the world over thousands of years, the native grasses provide important habitat for native wildlife. The fact that grasslands are one of the world’s most imperiled habitats alone makes the Lehigh Gap Wildlife Refuge ecologically valuable. Yet, these grasses also solve some very serious problems associated with our site. EPA mandated that we stop the widespread erosion on our property and prevent the mobilization of heavy metals into the food chain. Not only do the long (over 10-foot), fibrous roots of the grasses stabilize the soil, they also sandwich the metals between two growing layers of clean topsoil that form as the plants decompose above and below ground each year.

The grassland continues to thrive to this day. In 2002, the land was so toxic that little or no life – including bacteria and fungi – could survive. Since that time, hundreds of species of animal, plant, fungus, and bacteria have been documented on the restored Lehigh Gap Wildlife Refuge. Within its 756 acres, the Refuge features an amazing diversity of habitats, including forest, scrub, grassland, pond, and river. Such rare species as the Milbert’s tortoiseshell (butterfly), Blue Grosbeak (bird), and wild bleeding heart (flower) now call the Refuge home. One particular species – Homo sapiens– has returned in droves to study and explore the site. LGNC’s flourishing education program, 13-mile trail system (connected to the D&L and Appalachian trails), and countless recreational opportunities draw visitors from near and far.

LGNC serves as a model for innovative ecological restoration. In recognition of our unique conservation story, LGNC was honored with the U.S. EPA’s Excellence in Site Reuse award in 2014. Yet, our restoration efforts are never complete. We must continually employ adaptive management practices – including prescribed burning – in order to exclude invasive species and keep the metals from re-entering the ecosystem and food chain at toxic levels. LGNC is a living laboratory whose story is constantly evolving.

Growing from Our Roots

Volunteers are the backbone of LGNC. Our organization simply would not exist if it weren’t for the persistent efforts of a small group of visionary naturalists who shared a will to make a positive change for the environment and the local community. LGNC’s ‘founding volunteer,’ ornithologist Donald S. Heintzelman, planted the seeds of our grassroots story when he founded Wildlife Information Center in 1986 to advocate for wildlife preservation and to continue the Bake Oven Knob Autumn Hawk Count. That small group of mainly hawk watchers has grown into a robust family of members, supporters, and volunteers who are today involved with every aspect of LGNC’s conservation and education efforts.

Exemplifying the hard work of these many individuals, LGNC’s trail system and prolific native gardens have been designed, constructed, and maintained by dedicated volunteers. The Osprey House, too, is fully staffed by volunteers who greet visitors with a smile and provide information on LGNC and the surrounding region. Volunteers have also been the nucleus of LGNC’s growing education program, allowing our organization to teach over 10,000 students annually.

LGNC’s education program is based on our unique conservation work and our story of hope. The program has steadily developed since 2004 when Dan Kunkle left his teaching career and became a full-time, mostly volunteer staff person. Until recently, all field trips, in-school programs, and after-school programs were entirely led by an all-volunteer education team consisting mostly of retired teachers. The skills of these experienced educators have proven invaluable as LGNC has developed science curricula and engaged a growing audience.

Through contacts with area school districts and colleges, LGNC has attracted the attention of teachers and professors who bring their classes to the Refuge. Students from the preschool to graduate school levels visit to learn about nature, ecology, conservation, and often about our restoration work at the Lehigh Gap. We have developed a full slate of programs in cooperation with area teachers and professors. In addition, LGNC offers clubs, camps, art shows, a speaker series, and many other programs tailored to serve the diverse communities of the region.

LGNC actively seeks to make nature accessible to everyone. Thanks to grant support, we provide environmental education experiences for thousands of youth and adults in underserved urban and rural communities each year. Of all our education initiatives, LGNC has perhaps received the greatest recognition for our Color of Nature conservation leadership program. Through this initiative, we train and employ bilingual residents from the cities of Allentown and Bethlehem to teach environmental education programs within and beyond their communities. LGNC’s diversity initiatives, mostly pioneered by the bilingual Color of Nature leaders, have effectively engaged audiences who have historically had little access to nature and conservation careers.

Following the success of our conservation efforts in the Lehigh Gap, LGNC has sought to create and enhance native habitat elsewhere in the region through our Landscaping for Communities and Wildlife program. For five years, landscaping program director Kate Brandes collaborated with many partners to create nearly 40 native habitat gardens in the Lehigh Valley area. These include, but are not limited to, elementary school education gardens, college research gardens, urban residential gardens, and riparian buffers. LGNC also hosts programs and offers resources to educate the public on native landscaping and its many benefits.

In 2015, LGNC was invited to join the Alliance for Watershed Education of the Delaware River. This three-state initiative seeks to protect and restore the quality and quantity of the water in the Delaware River and its tributaries (including the Lehigh River). LGNC has become deeply involved in the leadership of the Alliance.

In the midst of all the rapid changes that have occurred in the Lehigh Gap since 2002, LGNC and its members have never lost sight of our mission. We continue to expand our education and conservation programs sustainably, always emphasizing quality over quantity. We hope that our story – supported by our ongoing education and conservation work – will continually inspire communities and individuals to achieve, sustain, and support healthy and connected ecosystems at the Lehigh Gap, on the Kittatinny Ridge, throughout the Lehigh River Watershed, and beyond.

In 2013, Lehigh Gap Nature Center received a “Sustainability Award” from the Delaware Valley Green Building Council.

Green Features of the Osprey House, our Visitor and Education Center

Solar Panels

• 65-panel, 23.4kW SunPower solar system was installed in June 2018
• LGNC is able to produce enough electricity to cover 100% of the building’s energy needs
• The system is preventing 49,560 pounds of carbon dioxide emissions each year

Super-insulated walls and ceilings

• Insulated concrete forms for basement walls (R30)
• 2” x 8” construction with 1” spray foam + 6.5” spray cellulose in walls
• Ceilings with 1” spray foam,15+” of spray cellulose
• Walls ~ R35 and ceilings ~R55

Geothermal Heat Pump HVAC

• Zoned so each room on each level has thermostat
• Programmable thermostats
• D-Superheater connects heat pump to water heater

 High efficiency lighting

• Fluorescent bulbs where possible
• Track lighting using CFLs
• Exhibit lighting with LED bulbs
• Occupancy sensors so lights are not left on accidentally

State of the art Stream Discharge Sewage Treatment system

• Includes aeration tanks
• 75% of effluent from filtration tank re-circulates through system
• Potable water discharged into river

Green construction materials

• Hardy board siding (composite made from cement and waste products)
• Spray cellulose insulation is recycled newspaper
• Low and no VOC paints
• Slate from local quarry on lobby floor
• Carpeting with 100% recycled backing and 35% recycled fiber
• Dolomite tile in library
• Trex composite decking made from wood waste
• On-site boulders used in landscaping and driveway retaining wall
• Habitat gardens with 100% native plants

Reuse of existing building

• The addition is designed to allow integration of old building into new
• Old building was gutted and made energy efficient

High Efficiency air-to-air heat pump in old building

Walls framed out internally to allow for addition of 3.5” fiberglass batts as additional insulation

1” foam sheeting added to ceilings to improve insulation

Storm water management

• All roads and garden areas are pervious surfaces
• Roof water collected in pond to maintain this educational feature of our landscaping
• Demonstration living roof on old springhouse

CollidEscape on windows to prevent bird strikes