Expanding Boundaries

By Uri Avin, FAICP, Kari Nye, and Jerah Smith

Harford County, Maryland, is a place of picture-perfect landscapes, working farms, and corridors of suburban development about 30 miles northeast of Baltimore. Its 400 square miles roll down from the piedmont to the Chesapeake Bay. About three-quarters of its 260,000 residents are concentrated on one-quarter of its land area. The remainder is a mix of farmland, woodland, and a scattering of rural homes.

This landscape exists because of a decision that Harford County made 43 years ago when it adopted its "development envelope," or urban growth boundary, to balance the needs of a growing population with the preservation of its agricultural and rural heritage.

Now the development envelope is running out of room and the county must consider its options, which include expanding that boundary. But how to do so sustainably? To determine its options, county leaders turned to two important resources: exploratory scenario planning, and an interdisciplinary team of students led by nationally known faculty advisors at the University of Maryland. That partnership has yielded important insights into how the county could solve its dilemma.

Like most counties in central Maryland, Harford adopted a broad array of growth management measures in the 1970s and '80s. Those efforts established a strong regulatory foundation for the state's incentive-based Smart Growth program in the 1990s. In 1977, in the early stages of a growth surge, Harford County set up its 25-year development envelope to accommodate a projected 2.5 percent annual population growth rate, allowing only one unit per 10 acres on the remaining land — a strict preservation standard at the time. The county doubled its growth capacity in 1982, after which the development envelope remained fixed.

Population has nearly doubled over the past four decades, absorbing most remaining greenfields within the development envelope. Predictably, housing availability, and thus affordability, is now much constrained. Within the Baltimore Metropolitan region, Harford's home values have risen the fastest in the past decade, up to about $286,700, according to the 2019 American Community Survey.

Harford is not alone in this. The National Center for Smart Growth estimated in 2018 that by 2040, housing demand would outstrip supply in central Maryland's eight jurisdictions — which already contain over three-quarters of the state's housing and jobs — by as much as 133,000 homes.

Harford's 2040 housing deficit ranges from 5,000 to 40,000 units, with tight, policy-driven projections making up the low end and market-driven projections developed by the Washington, D.C.- based Woods & Poole Economics at the upper range. This kind of shortfall, evident regionally, can exacerbate further flung development, stunt economic growth, lengthen commutes, and increase greenhouse gases.

Pockets of Harford County are characterized by rolling hills, older homes and infrastructure, large lots, and farmland. Photo by Kari Nye.

"Harford County is, in some ways, a victim of its own success with regard to preservation and growth management," says Harford County's Director of Planning & Zoning Brad Killian, AICP. "While this model has helped achieve the desired growth patterns and preservation goals, future growth may not be fully accommodated within the current parameters; this, we anticipate, may lead to growing conflicts between the need to accommodate growth and the desire to preserve remaining open spaces."

Counties in Maryland are legislatively empowered to forge their own land-use and zoning policies with few constraints from incorporated cities and towns. In theory, this means local remedies are available to address this housing supply crunch. In practice, however, the resistance to expanding growth boundaries from numerous stakeholders — often with conflicting priorities — means that meaningful expansions have rarely happened.

Harford County officials turned to the University of Maryland, College Park (UMD) for help. They recognized that a university can provide a neutral place to test difficult and controversial ideas or lend fresh perspectives to pervasive challenges faced by planning practitioners. In 2019, community planning graduate students from UMD tackled Harford County's housing strategy challenge, developing a framework plan for county growth beyond its longstanding development envelope. How they tried to do this sustainably is a story worth telling.

Applying a scenario-based approach in Harford County

Harford County partnered with UMD's Partnership for Action Learning in Sustainability (PALS). Administered by the university's National Center for Smart Growth, PALS is one of the largest such programs in the country and one of 35 members of the EPIC Network. The campus-wide program leverages faculty expertise and student ingenuity, applying relevant coursework to tackle sustainability issues confronted by local jurisdictions.

The partnership aimed to address various planning and infrastructure issues. The county's top priority: studying the pros and cons of a potential expansion of the development envelope into an adjacent 13,000-acre area known as Creswell.

Creswell's rural land-use pattern is a mix of farmland — including active farms and some in permanent preservation easements; extensive forestlands; scattered well-and-septic-system subdivisions or homes; and small-scale commercial pockets. This landscape spans two healthy watersheds and abuts the coastal plain. Despite its low-density development, the area is traversed by several arterial roads which carry heavy peak-hour traffic to regional destinations.

About 750 remaining development rights — or the zoning-conferred right to build a dwelling — presently exist in Creswell, with the majority allotted to parcels zoned for single-family detached housing at a density of one unit per 10 acres. Under the current scheme, development would carve up the rural landscape with sprawling, large-lot, low-density housing eating at the community's farming land base, cultural character, and environmental features, while doing little to increase the county's overall housing stock and affordability.

Several unknowns characterize this planning challenge: the strength of the future housing market; the ability of local regulations (such as concurrency for schools and roads) and budgets to cope with the impacts of development; and the volatile reactions of very diverse local and countywide stakeholders. All these uncertainties support an exploratory scenario approach to this challenge.

Scenario planning approaches are generally understood to focus on what ought to happen, as in a visioning exercise, where a desired end-state is prescribed. By contrast, and within the umbrella of scenario-planning approaches, exploratory or contingent scenario approaches are concerned with what might happen, bracketing various plausible outcomes, testing their implications, and suggesting how to move forward within a framework for action rather than a prescriptive blueprint. Ideally, such actions should be resilient enough to handle many of the imagined, evolving realities. Exploratory approaches can be applied at various scales and in qualitative and quantitative modes.

The project team established seven high-level goals to assess the exploratory scenarios developed for Harford County: conserve farming, protect the environment, preserve rural character, minimize traffic impacts, maintain adequate infrastructure, provide additional housing, and ensure a positive fiscal impact. If that sounds like an ambitious agenda, it was.

Developing the framework plan for Creswell

Identification of land constraints and opportunities provided a lens for focusing the scenarios and their evaluation. Key mapping included man-made and environmental constraints, community character analysis, and a land portfolio map. Background analyses, focused research on forces driving change and their likely implications, and a stakeholder values analysis surfaced four plausible but very different scenarios:

1. Densify Within the Development Envelope
2. Low-Core, High-Edge Densities
3. Selective Transfer of Development Rights (TDR)
4. East-to-West and West-to-East Expansion

A largely qualitative assessment of each suggested that the Selective TDR scenario had the greatest potential to achieve both the growth and preservation goals while resolving or mitigating their potential contradictions. Depending on market forces and the program design, that scenario could yield from 8,000 to 20,000 new homes — single family through multifamily — while providing enough flexibility to meet most of the county's other goals as well.

Rick Pruetz, FAICP, a national expert on TDR, says that the number-one success factor is ensuring that the demand for growth exceeds baseline density in receiving areas. Pruetz lent his expertise to this project, helping to define the market-based arithmetic that could guide Harford County in creating a TDR approach that appropriately wields densities and the locations of sending and receiving areas.

For Creswell, students developed a small-area TDR program to direct growth away from the actively farmed, character-defining core to large parcels at the region's urban fringe with easy access to future sewer lines. The resulting land-use pattern is a fine-grained juxtaposition of dense nodes along the edges, hugging a sea of preserved farm and forest land.

Randall Arendt, nationally recognized for his expertise on conservation and open space subdivision design (OSD), assisted in defining open space protection options through revising the existing zoning districts. Despite allowing for a large number of new houses in Creswell, the overall combination of small-area TDR and revised open space subdivision guidelines allows for the preservation of 67 to 77 percent of the area's agricultural land.

The TDR-OSD approach represents a big improvement over the baseline scenario for Creswell's future because it concentrates both housing and infrastructure, alleviating known land and infrastructure challenges that existing county tools could not mitigate.

Harford County welcomed the framework plan. "Importantly," says planning director Brad Killian, "the analyses have provided an impetus for modernizing current development regulations. The county will use additional recommendations of the report to further analyze options for growth and preservation in the Creswell area." The students' work has been recognized through three awards: Outstanding Student Project from Maryland APA, an Outstanding Student Project honorable mention from APA, and a Sustainable Growth Challenge Award from the Maryland Department of Planning.

Scenarios and a Final Framework Plan for Creswell

The challenge: accommodate population growth and housing demand while meeting preservation goals.

1. DENSIFY WITHIN THE DEVELOPMENT ENVELOPE

This is the Infill and Redevelopment option without an expansion of the development envelope. Densification on the scattered infill lots throughout the DE (blue circles), assuming opposition from the existing surrounding communities, would yield only about 2,600 new units and stress sewer and road capacities — a dubious trade-off.

2. LOW-CORE, HIGH-EDGE DENSITIES

Low densities (yellow) abut parks and preserved farms in the core, while higher densities (beige) abut existing development and highways along the edges. While this scenario could yield at least 15,000 new units, the concept ultimately conflicts with county conservation goals and embeds rural-urban conflicts in the heart of the area.

3. SELECTIVE TRANSFER OF DEVELOPMENT RIGHTS

In this scenario there are few large parcels (darkest red) and many smaller ones. Large parcels can better absorb development via sensitive site planning and provide better amenities, suggesting that a TDR program might work here. Incentive zoning could readily yield around 15,000 homes on receiving parcels from smaller sending parcels.

4. EAST-TO-WEST OR WEST-TO-EAST EXPANSION

This presents a phased suburban expansion from the edge of the development envelope eastward, yielding progressively more housing up to a maximum of 18,000 units. Another variant is a west-to-east phased expansion with different sewer and market logic. These scenarios, however, ultimately undercut county preservation goals.

FINAL FRAMEWORK PLAN

Receiving areas will be developed at different densities (shades of red) and will commit 35 to 60 percent of each parcel to open space. This will provide for excess absorption capacity from the sending areas (agriculture) to ensure a workable market for TDRs. This framework can provide for between 10,000 and 16,000 new homes in Creswell, while still retaining up to three-quarters of its land as undeveloped.

Growth Scenarios and Community Goals

Using various tools and models, the PALS program was able to show the impact of potential development scenarios.

Cnythzi Collection: Digital Vision Vectors. Source: UMD Partnership for Action Learning in Sustainability

Takeaways

We learned several lessons from this immersive experience in action-based learning. Working with planning students — along with insights from students from other disciplines — on real-world projects is a valuable way to build technical planning skills in emerging professionals, as well as soft skills like understanding and navigating political and contextual nuances. "I have never learned so much in such a short time," notes article coauthor Jerah Smith, who was a PALS coordinator and managed the Scenario Workshop.

Service-learning programs like PALS can augment local planning capacity and offer planners innovative and useful consulting services — at a fraction of the cost and using state-of-the art techniques and technologies, as well as access to well-known thinkers in the field. Further, local planners need not be afraid to ask student planners to tackle difficult, sensitive issues.

Finally, the methods and outcomes, including implementation guidance, are noteworthy and offer useful lessons in leading-edge methodology and curriculum design. The approach is transferable to counties in metropolitan regions all over the country facing similar issues.

Uri Avin is a research professor at the UMD's National Center for Smart Growth, where he founded the PALS program and also teaches in its Urban Studies and Planning Program. Kari Nye, a graduate of UMD's community planning program and former PALS coordinator, is now a planning strategist with &Access. Jerah Smith, also a UMD planning graduate and PALS coordinator, is now the municipal services director for City Explained Inc. The student project team also included Bilal Ali, Sarah Latimer, Nicholas Mackereth, Russell Ottalini, and AnnaLinden Weller.