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Managing Site Constraints During a 30-Year Journey

When it comes to land development, time traditionally is not a developer’s friend. Markets fluctuate, consumers’ preferences can be fickle, and a strict regulation one year can become even stricter before the project is complete.

In the 30-year process of turning an underground mine site filled with geological uncertainties into the thriving Stabler Center business park, Gannett Fleming has ushered the developer through countless permits, tests, and studies.

A Vision

In the early 1980s, Donald Stabler, founder of Stabler Companies, Inc., had a vision to create an office-research park that incorporated the mixed-use development of campus-like office and research space. Stabler envisioned developing a large tract of land to create an aesthetically pleasing and conservation-sensitive environment, while avoiding commercial and residential sprawl. In 1984, he obtained approximately 1,700 acres of land in Upper Saucon Township, Lehigh County, near Allentown, Pennsylvania, and created the Stabler Land Company to develop his vision.

Identifying the Challenges

The newly acquired land came with its share of bumps and pits. Being the site of a former zinc mine dating back to the mid-1800s, the land was filled with geological challenges. For years, groundwater had been pumped from the underground mines into the Saucon Creek that traversed the property. When the mines closed, pumping ceased and the groundwater aquifer was replenished, creating small lakes and submerging the underground mine workings. Sinkholes, common to limestone areas that contain faulted and fractured carbonate bedrock, were present.

Upper Saucon Township obtained the rights to extract water from the aquifer to supply water service. This led the township to adopt an environmentally sensitive overlay zone to address potential impacts. The ordinance greatly restricted construction within certain distances of critical geological features, such as sinkholes, closed depressions, and bedrock fracture traces. Additionally, development was impacted by the Saucon Creek’s riparian environment, which included a 100-year floodplain and multiple wetlands locations.

Smoothing out the Bumps

In 1985, Gannett Fleming started planning and developing what would eventually be known as Stabler Center. Faced with a significant anti-development faction within the township, Gannett Fleming and the project architect created zoning that was compatible with both Stabler’s vision and the township’s development and conservation goals.

Gannett Fleming led the design and inspection of project-wide infrastructure improvements, including roads, utility services, and stormwater facilities. As each phase of the project unfolded, Gannett Fleming addressed environmental aspects from the standpoint of both Stabler’s vision and regulatory requirements. Each project required an environmental assessment that addressed potential impacts on the natural habitat and recommendations to avoid or mitigate such impacts. General or joint permits were required for many of the improvements, and Gannett Fleming worked with regulatory agencies to enable an efficient and timely process.

The firm’s stormwater management approach started with a master plan that preserved natural features and created water features that complemented the park’s aesthetics. To address the carbonate geology issues, a series of lined “wet” ponds provided stormwater retention while serving as park amenities. Although stormwater infiltration was not a typical solution in the region at the time, Gannett Fleming showed that maintaining natural infiltration rates better served the environment by replenishing the aquifer without impacting the carbonate geology.

Avoiding impact to wetlands was the firm’s first priority, but occasionally environmental mitigation was needed to offset development impacts. Gannett Fleming’s environmental scientists worked closely with the Pennsylvania Department of Environmental Protection to design effective replacement wetlands and monitor the site to ensure their establishment.

Keeping up With Evolving Regulations

As with any long-term project, regulations and their enforcement changed throughout the years. Reviewing agencies tightened their requirements for stormwater quality and groundwater recharge. Permits required more detailed applications and took longer to process. Upper Saucon Township’s review and enforcement procedures also evolved, requiring more detailed investigations in the environmentally sensitive overlay zone and tighter reviews and regulations of environmental features, including floodplains, riparian buffers, wetlands, vegetation, animal and plant habitats, and geology.

Throughout this evolution, Gannett Fleming kept Stabler Land Company informed of changes in regulations and was proactive and responsive to the review agencies before, during, and after the formal review process. Robert Bower, former president of Stabler Land Company, commented on adapting to the evolving changes: “Without the significant contributions of Gannett Fleming, such adjustments to the changes of the political and regulatory climates would not have been possible.” Today, the development realizes a vision that began 30 years ago, complete with opportunities to live, work, and play.

Contact Peter S. Joyce, PE, via email for more information.