How Subdivisions Learn

How subdivisions learn: Promoting positive change in post-WWII suburban residential neighborhoods. Brian Dale Ray

Introduction Suburbia is becoming increasingly criticized. There are numerous alternatives, but none really address what to do with the existing residential neighborhoods. With this thesis I will review the common issues associated with these neighborhoods, identify potential alternatives, and apply hypothetical solutions to a subject neighborhood.

A Brief History of Suburbia “ Where dwell ye, if it to telle be? In the suburbes of a toun.’ quod he.” - Chaucer in The Canterbury Tales The idea of suburbs is as old as human settlements. Evidence of development up to four miles from the built-up areas of Ur in Mesopotamia In medieval Europe it generally referred to the areas outside of the city walls In the US the desire for suburbia was often related to the desires to avoid the pollution and chaos of the city, but also tied to the agrarian ideals associated with the founding of the nation.

Early Suburbs Suburbs have always been related to transportation. Early suburbs were limited by the distance one could walk, ride a horse, or travel by boat. The advent of the railroad expanded the suburban scale, both with streetcar communities and new towns on commuter rail lines. Riverside, designed by Frederick Law Olmsted in 1869, is an example of a new town. It is located approximately nine miles from Downtown Chicago.

Restrictive Covenants and Zoning Restrictions within suburbia came early. The Articles of Agreement Regulating the Use, Holding, and Enjoyment of the Rock Park Estate in the County of Chester date from 1837. No one could buy property without agreeing to these restrictions. The details addressed vehicles, lot size for a stable, restricted non-residential uses, limited the height of board fences, and mandated the state of repair for the private property. Zoning as we know it got its start in the early 20th century. Height, bulk, lot size, and certain types of structures were addressed in model legislation by the Massachusetts Civic League in 1912. By 1915 twenty-three towns had implemented similar regulations. (Hayden 120) Most early zoning was based on health and welfare issues, and intended to protect the home. “ Dirty” uses such as factories were intended to be kept separate from residences. There was also an interest in keeping the high-traffic uses away from quieter residential neighborhoods. Fire was also a common concern, and these concerns let to the regulation of the types, sizes, and separation of structures.

Post WWII Suburbia exploded after WWII The Great Depression and the war left significant unmet demand. Savings and government support enabled returning servicemen to buy homes in large numbers. Ten million new homes were constructed between 1946 and 1953. By the mid-fifties, annual housing starts exceeded one and a half million homes per year.

Automobile Focus While the automobile was a product of the early 20th century, limited new construction limited the effects. The change in transportation from a pedestrian focus to an automotive focus reduced the need for high density. Being able to drive reduced the perceived distance, which allowed larger lots and lower densities. At the turn of the 20th Century, 25’ x 100’ was a typical lot size for many larger northern cities like Chicago. This gave a density of roughly sixteen units per acre. By the 1950’s, typical lots were often 100’ x 100’, or four units to the acre.

Changes in Form The layout of suburbia changed considerably after WWII The Federal Housing Administration (FHA) helped standardize the form of suburbia through their lending standards. Their standards included such things as minimum lot sizes, setbacks, separation from adjacent structures, and the width of the house itself. Construction methodology changed as well. Much as industry had become mechanized and focused on mass-production, so to did the construction of houses. Contractors such as Levitt and Sons produced huge developments, rather than a few houses. Levittown had 82,000 residents in 1960. Modern Technology, especially air conditioning, also changed the house itself. Porches were no longer needed to escape the heat, and so were omitted from most houses. The form of the community also changed from gridded to curvilinear. Comparison of gridded plan with curvilinear plan suggested by FHA

Segregation This new suburbia was increasingly segregated. The financial community saw blighted neighborhoods as physical evidence of the melting-pot mistake. To them, cities were risky because of their heterogeneity, because of their attempt to bring various people together harmoniously. Such mixing, they believed, had but two consequences – the decline of both the human race and of property values. After WWII, the racial and economic segregation became more pronounced as people sorted themselves into neighborhoods of similar house types and prices.

The Problems of Suburbia These changes in suburbia caused a number of problems. These problems include the following:

Auto-Centric Transportation Disenfranchises those who cannot drive – the young, the old, the poor, and those with health issues. If you cannot drive you cannot participate in the American way of life. The Daily Vehicle Miles Traveled per person (DVMT) is significantly higher in the more sprawling communities than compared with the more dense communities. Atlanta, one of the more sprawling communities, averages 34 miles DVMT. Portland, OR, one of the least sprawling communities, averages 24 DVMT. Sprawl also impacts the rate of automobile ownership. The top ten most sprawling communities average 180 cars per 100 households. The ten least sprawling communities average only 162 cars per 100 households. Automobile reliance makes us dependant on oil. If the oil supply is limited, it can cause significant impacts on individuals and the American economy as a whole.

Limited Public Transportation Sprawl reduces the efficiency of public transportation. With reduced density there are fewer people within walking distance of transit stops. This increases the size and cost of the transit network for a given population, but also increases the time required for the travelers. These issues both increase the cost of providing service as well as reduce the likelihood that individuals will use public transportation. It takes approximately 15 dwelling units per acre (du/acre) to support a 10-minute bus frequency. At 7 du/acre 30-minute service can be supported. At about 4.5 du/acre hourly service can be supported.

Destruction of Community Modern suburbs have little useable public space. Historically, public space has served as meeting places, market places, and transportation. In modern times the market places have been privatized with controlled access, the meeting places limited, and the transportation network dominated by the car. Individual transportation reduces the opportunity for interaction, as people no longer run into their neighbors as they go about their daily life. Typical suburban areas also lack both the pedestrian focus and common spaces, and thereby further limit opportunity for informal interaction. The lack of public space is also both a cause and result of the stark dichotomy between the very public, automobile-oriented street and the very private individual house. When people’s needs are not met in the public realm, they strive to create it in their private places. As their needs are met in private places, they see little need for the public realm.

Lack of Diversity “ In most of our European immigrant pasts lies the story of a poor forebear in the same classroom or neighborhood as someone higher on the social or economic ladder, who inspired the poorer newcomer to succeed. Observing success within the boundaries of our own experience clarifies the possibilities and processes of social advancement stimulates healthy competition and ambition. It shows the way up.” (Orfield) Many low-density suburban developments have historically been similar in both types of units as well as cost, leading to similar types of occupants. Diversity of unit types, housing values, and housing tenure are all correlated to diversity of community. The monoculture of unit types poses problems for a changing society. While most of the houses were designed around the ideal of a nuclear family, suburbs now contain more nonfamily households – largely young singles and elderly people living alone. In 2000, 29 percent of all suburban households were nonfamilies. 27 percent were married with children.

Health Issues America is obese. This obesity is due in part to a lack of sidewalks, and destinations within walking distance. Low density makes distance a barrier. Single-use zoning further increases separation. Obesity has been found to be significantly associated with diabetes, high blood pressure, high cholesterol, asthma, arthritis, and poor overall health status. People are more likely to die in automobile accidents in sprawling regions. The top ten most sprawling communities average fifteen fatalities per 100,000 people per year. The ten least sprawling communities average nine fatalities. Pedestrians are also more likely to be killed in sprawling communities. In Atlanta, one of the most sprawling areas, pedestrians were killed at a rate of 2 per 100,000 people in 2004. This is 25% higher than the national average of 1.6 deaths per 100,000 people. The Hispanic population in Atlanta, which is more likely to be poor, has an even higher rate of 2.5 deaths per 100,000 people. This is 64% higher than the national average.

Environmental Impacts Low density development increases consumption of land. The consumption of land reduces and fragments natural habitat, and often eliminates prime farmland. Air pollution is increased by the reliance on the automobile and the pollution created by the exhaust. The top ten most sprawling communities had an average maximum 8-hour ozone level of 98 parts per billion (ppb), The ten least sprawling communities have an average maximum of 70 ppb. Increased impervious surfaces (i.e. roads and rooftops) leads to increased water runoff. Low density development requires more roads to serve a given population, and large lots encourage single-level houses with larger roofs. Much of suburbia was built prior to the Clean Water Act (established in 1972 and amended in 1977) was applied to land development. These areas typically lack runoff mitigation measures such as detention or water quality facilities.

Alternatives to Suburbia New Urbanism Proposes new communities based on historic, walkable examples. These areas would be higher density, mixed-use, and encourage the creation of public spaces and community. Smart Growth Smart Growth policies are intended to spur development patterns that allow citizens to make more environmentally, socially, and economically sustainable lifestyle decisions. In general, smart growth invests time, attention, and resources in restoring community and vitality to center cities and older suburbs. New smart growth is more town-centered, is transit and pedestrian oriented, and has a greater mix of housing, commercial and retail uses. It also preserves open space and many other environmental amenities. Problems with New Urbanism and Smart Growth Neither addresses existing residential neighborhoods.

Possible Solutions / Retrofitting Existing Neighborhoods Increased Density As densities rise, trips get shorter, transit and walk mode shares increase, and vehicle trip rates drop. All of this translates into lower VMT. By various estimates, doubling urban density results in a 25-30 percent reduction in VMT, or a slightly smaller reduction when the effects of other variables are controlled. Allow for accessory dwelling units, infill development, subdivision of existing lots, and other strategies. Increased diversity through the provision of different types of housing units, and allow for appropriate non-residential uses. Increased connectivity and enhanced transportation options. Additional sidewalks on existing streets. Additional connections to the existing road network to shorten trips. Incremental growth to promote gradual, community-driven change. Mitigating Environmental Impacts Public Improvements Enhance the streetscape through street trees and on-street parking. Create public spaces.

Application – The Cedar Creek Neighborhood I selected the Cedar Creek neighborhood in Athens to test possible alternatives. It is located approximately 4 miles southeast of the downtown area. The initial two phases of Cedar Creek were developed in 1965 and 1966. They include 289 single-family lots, on which 285 houses have been constructed. There are also 24 duplex lots with 24 residences. Single-family lots range from roughly 0.5 to 1.5 acres. The overall area is approximately 224 acres, for a net density of about 1.4 units / acre. The proposed improvements include the following:

Roadway Improvements Most roadways within the Cedar Creek neighborhood have sixty to eighty foot wide right-of-ways, twenty-eight foot wide roadways, rolled curb and gutter, and no sidewalks. These road ROWs should be improved with the following: 5’ to 8’ sidewalks. Vegetated swales for water quality. Street trees on 25’ to 30’ spacing. Encouragement of on-street parking. Improvements should be phased in over time, starting with one side of the primary streets, then one side of the secondary streets, and eventually providing all improvements to both sides of all streets.

Entrance Park This area is typical of most streets, but includes a wide central median and an open, uncontrolled three-way intersection. ROW would be enhanced with sidewalks, vegetated swales, and street trees. The unused 40’ median would be enhanced with: Community garden area. Dog Park. Roundabout reduces pavement area, enhances circulation, and creates an open space.

Alley The creation of an alley at the rear property line of some blocks may be a way of reducing the overall block size as well as providing for additional access to the rear of larger lots. The alley would have a 30’ ROW (15’ from each property) and served by an 18’ one-way road. This additional access could serve to minimize additional driveways from the existing streets as well as provide access to garages or additional units located along the alley. Concepts shown include the following: Lot split with new single-family residence. Detached 3-car garage. Townhouses. Combined accessory dwelling unit, pool house, and garage. New lot, duplex units

Stream Corridor The stream corridors within the neighborhood are presently undeveloped and unimproved. If the property adjacent to some of the stream channels were acquired, it may be possible to utilize them for water quality and recreational purposes. Small detention pools within the existing stream channel could be created for stormwater management. These pools would be in the form of low dams or weirs that make use of the existing topography. The pools should be designed in a way such that the water would be shallow (less than 24” to 30”) and held for less than 24 hours. It is also possible that these stream corridors be used for recreational purposes by the provision of access trails adjacent to the stream. These trails could serve to address both maintenance access issues as well as an opportunity for people to interact with nature. The acquisition of the stream corridor, access, and SWM improvements would also include stream restoration efforts to stabilize and improve the existing stream bed.

Pedestrian Connection Where obtaining a full street connection is not possible, a pedestrian connection may be a suitable alternative. This ROW would be located along the property line of two single-family lots, be twenty feet wide, and require ten feet from each property. A six foot wide pathway is shown. This walkway would allow a direct connection between the neighborhood and the adjacent school and park. The creation of this connection would enhance pedestrian and bicycle access.

Street Connection, New Lots Adjacent This concept shows the creation of a new roadway connection and the addition of both detached and townhouse dwelling units. Five lots were impacted, with two houses eliminated, the rear yard of two lots utilized, and minor adjustment to the lot of the fifth property. The overall project encompasses 82,031 sf (1.88 acres), for a total of 7.45 DU/ac. The seven detached lots range from 3,967 sf to 6,721 sf. The seven townhouse units have a 25’x40’ footprint, and include a single-car garage plus one driveway parking space. They are a minimum of 20’ from the rear property line. The roadway is 28’, and assumes on-street parking for the residents. A SWM facility is shown behind one townhouse block.

Infill w/ Connection This concept shows an infill development and street connection between the Cedar Creek neighborhood and the Spring Lake neighborhood. The infill development utilizes three large lots (3.7 ac total) of the Cedar Creek Neighborhood, and two smaller lots (0.7 ac total) for a total of 4.4 ac. The plan shows 11 single-family detached dwellings, and 25 townhouses, for a total of 8.2 DU/ac. The single-family lots range from 4,600 to 8,500 sf. All houses are shown as having a single-car garage and one space for parking in the driveway, with additional on-street parking. The Townhouse units have a 25’x40’ footprint, with a single-car garage and one driveway parking space. 45 additional parking spaces are provided for the overall development. A 0.5 ac open space is provided for the use of both the residents as well as the larger neighborhood, and includes an area for a small SWM facility. The townhouses adjacent to the open space would be designed so their front faces the open space. The design includes a roadway stub-out to the property to the west, which would allow for a future connection to the adjacent properties if they were redeveloped.

Lot Split 1>2 This concept shows one 7,800 sf lot split from a single 26,000 sf parent lot at the corner of Ravenwood Run and Cedar Creek Drive. The new lot is approximately 15’ from the residence on the parent property at the closest point. The new lot is shown with a 30’ front yard setback, 10’ side yard setbacks, and a 25’ rear yard setback. The house is shown with a 1,800 sf footprint, a single-car garage, and room for two cars to park in the driveway.

Lot Split 2>3 This concept shows where a new lot is created between two parent lots, from a portion of each of those lots. The existing Lot A was 21,800 sf, and contributed approximately 30’. The house on Lot A would be 15’ from the new lot line. The existing Lot B was 22,400 sf, and contributed approximately 25’. The house on Lot B would be 10’ from the new lot line. The created lot has a width of approximately 55’, and would have an area of 9,500 sf. A 30’ front yard setback, 20’ rear yard setback, and 5’ side yard setbacks are shown. The design shows a 1,400 sf house footprint and a detached 24’x24’ garage. It is possible that the garage has an upper accessory dwelling unit or other useable space.

Infill One>Five This concept shows where a single vacant 0.74 ac lot could be redeveloped for 5 zero-lot-line dwelling units. Overall density would be 6.8 du/acre. Each new lot is approximately 3,100 sf, and shows a dwelling footprint of 1,100 sf. The units are spaced 10’ apart. Each unit is provided with 2 dedicated parking spaces, with 7 additional parking spaces provided for the overall development. There is a 10’ common space buffer between the individual lots and the adjacent lot line. A small SWM facility is included adjacent to the parking area. A small gathering space is included adjacent to the sidewalk at the front of the property. This space may included benches or a bulletin board, and would be shared by both the subject property and the larger neighborhood.

Accessory Dwelling Unit This concept shows an accessory dwelling unit located at the rear of an existing single-family lot. This accessory dwelling unit would be 24’ x 40’, with a two-car garage and storage on the ground floor, and an apartment on the upper level. The structure would utilize the existing driveway. It would have a ten foot side yard setback, and a twenty-five foot rear yard setback.

Potential Barriers to Change One of the major issues related to how suburbia can grow and change is the response of the existing residents to the infill and modification process. While individuals may be supportive of the general concepts as applied to the larger community, they are often opposed when change comes to their own neighborhood. Prior to any possible change, there must be recognition that there is a problem. Zoning guidelines and homeowner regulations further reinforce the status quo, as any random, unplanned change is perceived as a threat to everyone’s property values.

Additional Barriers to Change Existing residents often have great concern regarding change including the following: Substandard construction practices (materials and design) of the infill development would reduce the value of their property. This has been a common concern throughout the ages, as construction practices change. When post and beam construction was common, the new-fangled balloon framing methods were looked down on as shoddy. Yet, in today’s terms, we often value those older buildings framed for their solidity. “Seen in the context of imaginary spaces it is almost wholly irrelevant as to whether or not infill housing will, in fact, become the slums of the future. What is important is that many people living on a residential quarter-acre section believe it is so, and their beliefs govern their interpretations and responses.” Rental housing will bring undesirable neighbors to the community, as renters are often seen as creating problems. Changes to the ‘way of life’ in the community. The new inhabitants would be different, and less likely to be a family with children. This fact was sustained by the research, as residents of the infill development were less likely to have children than those residents who lived in single-family homes. The increased activity within the community was unwelcome. Despite research showing that ‘eyes on the street’ enhanced security and safety, many residents responded negatively to the additional traffic and activity brought by the new neighbors. Increased diversity of people & lifestyles associated with infill housing also chances the ‘sense of place’ associated with those neighborhoods.

Managing Change Change will likely happen only under certain circumstances. These may include a dramatic increase in the cost of gas, increased congestion of the roadways, and an increase in the value of land. It may be a result of a single reason, but more likely a combination of all three factors. Without a combination of these factors, there will be limited demand for change, and residents will likely be highly resistant to it. The idea that the changes would make the community a better place is a nice theory, but abstract and probably not attractive enough to overcome the ingrained fear of change.

Rate of Change As the problems of suburbia were slow to emerge, so too will the solutions be slow to happen. Awareness of the problems and possible solutions will be slow to take place in the community. These solutions are long-term, and like many efforts, a slower time-frame will allow the community to adapt to the process. A slower time-frame will also allow incremental change and review of the impacts, with an associated modification of the process to ensure that all of the needs are met as well as possible. Some items such as infill or unit construction should be bottom-up, and driven by the residents. This would allow them to change their own neighborhood, and not force them to change. Other items such as sidewalks, SWM, and street connections have to be top-down. They can be implemented slowly, over time, to allow residents to become comfortable with the idea of change. They may also be done on a priority basis, with the most important parts done first. These critical parts may include sidewalks on the main areas, or pedestrian and bike connections within the network.

Financial Considerations Methods of paying for neighborhood-wide improvements must be considered, especially in eras where communities are having difficulties providing the basic services. Financial alternatives might include: Impact fees from the infill development Enhancements as a part of normal infrastructure rehabilitation Tax increment financing (TIF) based on the increased value of the neighborhood with the improvements. Impact fees show the greatest potential. New construction within existing neighborhoods utilizes the existing streets and utilities, and thereby saves on construction costs. It may be possible for the community to capture some of this savings in the form of impact fees to pay for the community improvements. In this manner, the community may be less oppositional to new construction, as they see some benefit. These neighborhood amenities may include such things as sidewalks, roadway improvements, or neighborhood parks. These impact fees may be spent on direct improvements, or placed in a fund for larger projects. It may be possible to waive part or all of these fees as a means of promoting desired projects such as affordable housing or the inclusion of community space.

Conclusion In the twelve-step programs for addiction recover, the first step is to acknowledge that there is a problem. For suburban neighborhoods to change the process is the same: the community must recognize that problems exist. Until that occurs, neighborhoods will resist all efforts towards promoting change from external forces with all of their might. The very idea that change is necessary implies that they are flawed to begin with, which insults the existing residents. The suburban ideal of a house on a quarter acre has been enshrined as the American ideal. In buying their homes they have bought into the ideal. Communities are resistant to change, and threatened by possibilities they don’t understand. Only once communities recognize that the automobile focus of the transportation network is limiting, that density isn’t an evil word, and that change isn’t always for the worse then it may be possible to allow for positive change within their neighborhoods.

Implementation The design solutions are easy; increase density, increase variety of size, ownership structure, and uses; create additional vehicular and non-vehicular connections; and enhance the public realm. The political solution and implementation is much harder. All alternatives will have to be carefully discussed, reviewed, and evaluated over time to determine what projects are suitable for each neighborhood. The effects of each change will have to be compared to the goals as the neighborhood evolves, and each alternative modified to fit the new conditions. While difficult, these changes are important. One definition of insanity is doing the same thing over and over, but expecting different outcomes. If we are not willing to change our neighborhoods, we should expect no positive changes from them. Worse yet, in the face of changing economic and social forces, without change the neighborhoods may be vulnerable to decline.

How Subdivisions Learn

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