Twin homes on W. Gravers Lane were built on a subdivision “by right.” Current zoning laws allowed for the lot division and the construction of two new homes. (Photo from 2017 during construction)

by Celeste Hardester

Third of a series from the Chestnut Hill Community Association Physical Division

“Suburb in the City.” That’s how David Contosta described Chestnut Hill in his locally famous book of the same title, published in 1992. But how did it come to be that way?

In Pennsylvania, of course, everything goes back to William Penn, who from the very outset created three counties, including Philadelphia. He also saw to the creation of townships, which for a long time served as the organizing system governing many communities. But come the 1830s-40s, issues related to immigration and migration had surpassed the abilities of townships to manage. As conflicts and even riots occurred, there was little ability to police them. All the issues related to maintaining safety were increasingly challenged by lack of revenue and consistent services. 

So, remarkably, in 1854, political stars aligned when Harrisburg, in one of its earlier interventions into Philadelphia, passed the Consolidation Act, bringing all of Philadelphia County under the authority of the heretofore small City of Philadelphia.

Chestnut Hill, long a retreat from the heat and ills of city life, found itself within the borders of a burgeoning city. The repercussions of that decision filter down to us today, with the dichotomy of being part of a large city while surrounded by nature, combined with limitations inherent to being governed by regulations that apply city-wide, including zoning code.

Philadelphia’s first zoning code was established in 1933. Its formulation was largely guided by the built environment, which holds true today. In residential areas this means that if a block is comprised mostly of twins, the zoning applied to that block is for Residential Single-family Attached (RSA) housing. Other blocks that are largely single homes will be zoned for Residential Single-family Detached (RSD). These RSA and RSD categories are known as zoning districts, and within each are several levels based on standard lot sizes with required square footage, required length of street frontage and more.

In many cases, this system works well enough. In Chestnut Hill, for properties near to Germantown Avenue, the land was significantly developed years ago. There are relatively few opportunities for subdivision, though such situations do occur at times. The new twins that were built at 101 W. Gravers Lane are an example of this. The subdivision was “by-right” meaning that it fit within the parameters of the zoning code and required no support from the community or consent of the Zoning Board of Adjustment.

Further away from the Avenue it is a different story, and this is where Philadelphia zoning code doesn’t in any way adhere to what is on the ground. The residential zoning district in Philadelphia that accommodates the largest lots is RSD-1, with the requirement that the lot be at least 10,000 square feet (approximately a quarter acre), with at least 75-feet of street frontage.

A casual drive around Chestnut Hill’s back streets will make evident that many properties are considerably larger than a quarter acre. Indeed, half-acre, full acre, at times even multi-acre lots are not uncommon. These are all zoned RSD-1.

What difference does it make? This diminutive 10,000 square foot minimum means that many properties in Chestnut Hill are ripe for subdivision. As properties change hands, as generations move on, large properties can become a burden to some and a financial opportunity to others. If a developer purchases a large property, they may or may not keep the original house, but they often subdivide the remaining land into buildable parcels.

Sad to say, this outcome is possible in large areas of Chestnut Hill. It is even ironic because the City of Philadelphia has an aggressive goal of increasing tree coverage to 30 percent from a current figure that is well under that number. So what can be done?

The District Plan that was completed by the Philadelphia City Planning Commission in 2018 made clear that one option we do not have is increasing the minimum lot size. (The reasons for this are significant and too lengthy for this article.)

However, the Chestnut Hill Community Association and the Chestnut Hill Conservancy have been working on tools designed to ameliorate the effects of development that can occur by code. Already in play are two important options: property easements and individual historic designations. Both of these options can protect the land surrounding a structure. Additionally, the Zoning Code provides the option of a Neighborhood Conservation Overlay (NCO). Such an overlay is not a panacea, but it can create standards within which development can be contained.

In 2020 the Chestnut Hill Community Association and the Chestnut Hill Conservancy will take steps to move all of these tools forward, seeking to preserve our rich heritage and provide guidelines for appropriate development in the future. More detail about these efforts will be forthcoming in future articles in this column.

Celeste Hardester is Development Coordinator for the CHCA Physical Division.