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All local streets leading from it are very narrow curving service oriented cul-de-sacs (See Figure 3.8). Open space and low density residential land uses dominate the plan. One liability is the lack of commercial services nearby. A small commercial area includes a restaurant and offices, however most shopping and other daily services are within biking (not walking) distance. As a result, most residents drive to commercial centers in Davis, Woodland or Sacramento for more significant purchases. [Figure 0.6 and 0.7 here] The stormwater management and food production capacity enabled by this open space network is significant. Within the open space network is a finely-scaled open drainage system. With the exception of peak storm events, Village Homes' open spaces manage all of the stormwater runoff generated on-site at lower capital and infrastructure maintenance costs than those experienced in adjacent neighborhoods. In addition, residents are able to grow about 24% of their own fruits and vegetables (about a third more than adjacent neighborhoods) and gain modest income from the almond crop.xiv This green neighborhood works and is highly valued by the residents. Surveys of Village Homes and adjacent neighborhoods reveal that Village Homes residents know more than twice as many of their neighbors. And like Orenco Station, the strong sense of community has economic value. When Village Homes houses are put up for sale, they tend to sell quickly and at a premium compared to similar houses in adjacent neighborhoods.xv Despite Village Homes' considerable contribution to environmentally oriented development patterns, it also has environmental liabilities -- notably its size and density (75 acres and 240 dwellings or 3.5 per gross acre -- a density roughly equal to the more conventionally patterned suburban neighborhoods adjacent). Neighborhood scale development patterns of that size and density are generally poor at conserving land and fail to generate sufficient market for the transit and on-site services, or the inter-neighborhood connectivity that tends to reduce demand for automobile trips. On the other hand, Village Homes has attracted residents interested in reducing environmental impact through other, more behaviorally based means. Compared to adjacent neighborhoods, Village Homes residents tend to own fewer cars and use them less, generating approximately 16% fewer vehicle miles per car. They also consume about 34% less electricity, in large part due to the passive and active use of solar energy for space conditioning and hot water heating made possible by strategic orientation of its blocks, lots and buildings through site planning.xvi Growing compact AND green If evaluated against an over-riding goal to manage urban growth, and concurrently conserve land, air and water quality, energy, quality of life and community -- how does a model of compact neighborhood like Orenco Station compare to a green neighborhood like Village Homes? [Table 0.1 here] Although it is impossible to make this comparison rigorously with the data available, it is possible to draw general conclusions. Orenco Station is certainly the better performer against measures related to land conservation. Village Homes is certainly the better performer against measures related to water quality and probably the better performer against measures related to energy conservation. More of Village Homes' land is set aside for open space, and strategically allocated to environmental, food, transportation and social purposes. Less is allocated to vehicles. Comparisons against measures related to automobile trip demand and air quality are not possible. Although, both perform better than conventional suburban neighborhoods, comparable information is not available to determine which of the two more effectively reduces trip demand per household. Orenco Station is certainly more supportive of transit use and Village Homes is probably more supportive of bicycle use. Both are supportive of pedestrians. Village Homes' infrastructure costs less to develop and maintain. Both perform well against measures of community -- albeit for very different reasons, and market value relative to other neighborhoods. The more important question is perhaps not which pattern is better, but to what degree can their positive attributes be merged to perform better against multiple environmental objectives -- land, air, water, urban forest and habitat -- at the same time? Or, in physical pattern terms, how and to what degree can development patterns such as Orenco Station be integrated with open space patterns such as Village Homes? In the end, if present sprawling development patterns persist, the environmental consequences will likely be unsustainable, even devastating. More agricultural land will be consumed by sprawl. Habitat will be fragmented and destroyed. Pollution will increase. Water systems will be degraded. People will spend more and more time in traffic, getting less and less healthy. These trajectories are well established, but solutions have been elusive. Regions, cities and neighborhoods must find solutions to reverse these trends and many have started. Throughout North America there are examples of nascent solutions to many of these ills, but few that tackle compact, green development holistically. We propose that green neighborhoods, as described in the chapters that follow, are the building blocks for metropolitan solutions.

Contents Preface Introduction Growing compact Growing green Growing compact AND green Chapter 1. Green Neighborhoods Green neighborhoods An example: The Royal Avenue Plan Network and fabric, green and gray Case studies Chapter 2. Case Studies Overview Radburn Stapleton Playa Vista The Beach Coffee Creek Center Orenco Station Heritage Park Villebois Chapter 3. Green Networks Fragmented systems Engaging landscape ecology Green networks and form Connecting region to neighborhood Green networks strategies Chapter 4. Gray Networks Designing street networks Hybrid networks Green streets Skinny streets Streets as civic amenity Gray networks strategies Chapter 5. Gray Fabric Compact neighborhoods Density Complete neighborhoods Neighborhood diversity Gray fabric strategies Chapter 6. Green Fabric Urban forest as green infrastructure Planting green streets Defining neighborhood space Green fabric strategies Chapter 7. Urban Water Sustaining urban water Stormwater as civic amenity Linking across scales Whole water systems Urban water strategies Chapter 8. Getting to Green Neighborhoods Thinking, seeing, knowing ‘green' Nested parcels, districts, neighborhoods, regions Integrating compact, green and gray: Southeast False Creek, Vancouver Neighborhoods are Green neighborhoods have... References Notes Index Introduction "Urban form directly affects habitat, ecosystems, endangered species, and water quality through land consumption, habitat fragmentation and replacement of natural cover with impervious surfaces."i Urban development in the USA reached a suburban tipping point shortly after World War II. In the years following the war, about half of USA' 140 million people lived in metropolitan (urban) areas and about half lived in non-metropolitan (rural) areas. By 1950, population distribution had shifted to metropolitan areas --the tipping point was reached and after that urban populations exceeded rural in numbers. This shift accelerated with subsequent population growth in the decades that followed. By 2000, two generations later, U.S. population had doubled to about 281 million and the people in metropolitan areas outnumbered the non-metropolitan population by about four to one. Where that population tended to settle within metropolitan areas is the more significant trend. The U.S. Census Bureau defines suburban populations as the population in a metropolitan area minus the population of the central city. The preponderance of metropolitan area growth of the past fifty years was concentrated in the suburbs (50%) while central city population (30.3%) declined. By 2000, suburbs had become home for roughly half of the U.S. population.ii While the population roughly doubled between 1940 and 2000, the housing stock tripled in numbers. In 1940, there were just over 37 million housing units in the USA Over the next sixty years population slightly more than doubled (214%) while average household size shrank by about a third (30% from 3.68 to 2.59).iii The combination -- increasing population plus decreasing household size, significantly accelerated demand for new housing units. By 2000, the U.S. housing stock had expanded to about 116 million units. Due in part to a convergence of multiple social, economic and policy factors by 2000, home ownership rates had increased from about 55% to 67.4% despite the fact that the overall number of households competing for homeownership increased at the same time.iv Because the majority of the new households formed could afford to buy housing units, many more chose to make that investment in larger, single family detached houses outside central cities. Much also changed about the urban development patterns of these new places. Between 1950 and 2000, for example, the typical new home in the U.S. more than doubled in floor area from two bedrooms and one bath in 1,000 s.f. or less (at an average cost of {dollar}11,000) to three or more bedrooms and two and a half baths in 2,265 s.f. plus garage (at an average cost of {dollar}206,400).v These new houses were also built in more decentralized and distributed suburban models rather than compact urban models common to pre-World War II cities. This in turn precipitated a substantial investment in automobiles and transportation infrastructure (roads and parking lots) needed to connect widely distributed homes with work and services. Concurrently, the urban areas and the neighborhoods in which these houses were situated changed significantly as well. Cities became significantly less compact, and land uses became less mixed and more stratified overall. Urban areas grew both in number and in area. The urbanized land area of the largest metropolitan areas of the U.S., for example, quadrupled between 1954 and 2000.vi With some regional variation, the rate at which non-urban land has been developed has greatly outpaced the rate at which population has been growing, by a factor of roughly two to one. From 1950 to 1970, for example, the population of Phoenix grew 300% while its urbanized area grew 630% to become one of the more telling illustrations of poorly managed growth. Much of the outward urban expansion was due to very low density suburban development. Over that same 1970 to 1990 period the population of Nashville grew 28% while its urban area expanded 41% and the population of Charlotte grew 63% while its urbanized area expanded 129%. Still other cities lost population while they concurrently grew outward in size. Detroit, for example, shrank 7% in population while urbanized area expanded 28%. The population of Pittsburgh shrank 9% while its urbanized area expanded 30% and the population of Chicago increased 1% while its urbanized area expanded 24%. While population growth and urban land area are coarse indicators of the implications of development pattern, other evidence illustrates how cities often decentralize within their own borders. Many larger U.S. cities (particularly those in warm and dry climates in the West and South) grew over the 1990's -- approximately one quarter of them at rates greater than 16%. Many also successfully attracted new population to their central areas. However, in most cases, with some regional variation, central city population growth was balanced by losses in the neighborhoods immediately surrounding central areas and overwhelmed by much higher rates of growth near suburban edges. Overall, populations of most U.S cities decentralized toward suburban perimeters during the 1990s. The U.S. southeast, for example, set the pace with a suburban growth rate three times that of central cities in their region.vii These trends show little indication of slowing down. On the contrary, they seem to be increasing, in some cases even faster. Between 1992 and 1997, the national rate of urbanization more than doubled to 3 million acres annually. An urbanized footprint roughly equal to San Diego, California was added over the five years.viii Even cities noted for vital centers and compact growth share this experience. Vancouver, British Columbia, for example, is widely cited for its dense, livable central city and robust investment in urban infill. Between 2002 and 2003 -- a very strong year for residential construction and sales in the central city, that population remained unchanged while population outside the central city increased by just over 1% overall. In other words, despite significant new dwelling construction in a thriving central city, Vancouver was unable to redirect net growth away from all but a few of its suburbs.ix This pace and extent of suburban growth has significant consequences. The impacts on the environment have become familiar.

Natural features are cleared to make way for development -- wooded areas are cleared, streams are culverted or channelized, wetlands are filled or fenced, topography is leveled. Agricultural land, natural resource lands (forests and wetlands, for example) and habitat areas have been forever lost. Or new development has cut them up into smaller and less productive fragments, with significant environmental and economic consequences. Additionally, there are livability consequences of dispersed land uses. Shopping, recreation and schools are located far away from each other and often separated from residential areas by wide, fast streets and expansive parking lots. Travel distances increase while pedestrian safety decreases, making it difficult to live without automobiles. Typical suburban development patterns are characterized by poorly connected street networks. These, in turn, influence people's travel choices and behavior. Frequently there may be only one route to get from place to place, and that is often ‘the long way' as the crow flies. Travel lanes of the streets that make up the network are sized and scaled for the mobility of cars and these precipitate poor transit ridership and service. Pedestrian and bicycle facilities are second class and dangerous. Sidewalks are often adjacent to travel lanes (no planting strips) exposing pedestrians directly to rapidly moving traffic vehicles. Residential streets often do not have sidewalks, or if they do, sidewalks are interrupted by driveways so that cars and garages dominate them. As people are forced to drive more, fossil fuel consumption increases. This, in turn, impacts air quality, which continues to decline despite significant improvements in the design and engineering of cars and fuels. The bigger symptom of all this driving is that green house gases increase, and so does the rate of global warming. Water resources and the quality of the water near urban areas have also declined. Typical suburban development dramatically increases area of impervious surfaces such as pavement and roofs. What's not impervious is frequently chemically managed lawns or landscape that, together with greater concentrations of automobiles contribute to erosion, pollution and ground water reduction. Other, less tangible environmental and health consequences of sprawl have been more difficult to establish. However, as the science, technology and tools to measure these consequences become more sophisticated, the adverse effects of sprawl on our health and quality of life are discovered. For example, many suburban dwellers spend much of their lives in cars, and as distances and congestion increase so does commuting time. Health has declined. Rates of obesity, heart disease, diabetes and respiratory illness have increased.x Nonetheless, suburbs remain the destination of choice for most people. And by almost any demographic or economic measure, building this ever-expanding suburban landscape remains the dominant planning and design project of our day. Ellen Dunham-Jones concludes that approximately 76% of new population growth, 95% of new office space (and jobs) and 75% of new construction expenditures are concentrated in the suburbs.xi While suburban growth remains a resilient in many cities, the development patterns into which suburban growth has been accommodated are beginning to change. The contemporary challenge for many cities is how to stem the rate of outward expansion by encouraging so-called smart growth--more compact, pedestrian friendly development patterns, that consume less land and allow transportation choices. Growing compact Portland, Oregon is one example of a city that has, since the mid-nineties, focused on directing population growth into targeted compact neighborhoods. Working within the context of state growth management policies that require new development to be within urban growth boundaries, the metropolitan region coordinated overall growth, and land use and transportation planning in its Region 2040 plan. Growth would be concentrated at town centers located at transportation nodes, most being along light rail lines. Orenco Station illustrates one successful town center (see case studies). [Figures 0.1 and 0.2 here] Orenco Station is a new ‘greenfield' transit-oriented neighborhood in Hillsboro, Oregon on the western perimeter of the Portland metropolitan area, approximately 20 miles from downtown. Orenco, located at a rapid transit station, was planned in 1995 and 1996 to accommodate 1,835 dwellings and a mixed commercial center on a 156 acre site. Density targets were set at 12 dwellings per acre gross density -- roughly three times that of the prevailing pattern in Hillsboro and other Portland suburbs. As of 2004, the development was achieving those targets. Orenco Station demonstrates how transit-oriented, compact development patterns can succeed in a perimeter suburb and, that planning and design quality is crucial to that success. Initial sales exceeded projections and dwelling unit prices ran about 20 - 30% above area averages. The reasons have been attributed in part to physical planning and design -- the social vitality of a mixed use town center and community open space in combination with the pedestrian orientation and scale of streets.xii [Figure 0.3 here] A subsequent evaluation of social and transportation indicators reported a strong sense of community and some improvement in transit use as well. A convincing majority, 78% of residents surveyed reported a greater sense of community compared to their previous neighborhoods. Almost three quarters of residents reported an increase in transit use over their previous neighborhoods, but they still use private automobiles for three quarters of their commuting trips.xiii With triple the residential density of its neighbors, Orenco Station illustrates some successful strategies for land conservation and air pollution reductions, issues of water quality, urban forest and habitat have not been planning or design priorities. Growing green Village Homes, near Davis, California, is considered a prototype ‘green neighborhood' by many in the USA It was conceived, designed and developed by Michael and Judy Corbett in the mid-1970s. An adaptation of Stein and Wright's 1929 plan for Radburn, Village Homes demonstrates a small scale neighborhood plan woven together with open spaces to achieve goals of community, energy conservation and environmental awareness. In addition, Village Homes demonstrates a number of socially, ecologically and economically innovative features such as a pedestrians first, automobiles second circulation network, surface drainage systems, neighborhood orchards and gardens, and lot and building orientation for solar energy. [Figures 0.4 and 0.5 here] Approximately a third of Village Homes' site plan is allocated to community and public open space. Another 18% is allocated to public streets. At the core of the plan is a hierarchical network of open spaces. Beginning at the smallest scale, private courtyards and gardens adjacent to houses connect to small common areas between small groups of houses. These in turn connect to larger greenways accommodating stormwater drainage, pedestrian and bicycle paths at the scale of a block. These in turn connect to larger public open spaces and agricultural landscapes of orchards, vineyards and community gardens. A connected network of pedestrian and bicycle routes is well integrated with the open space and the street network, making it easier to walk or bike from one part of Village Homes to another than to drive. The furthest travel distance within the network is less than five minutes and many routes can be negotiated without crossing a street. Automobile transportation elements and functions are secondary and much less direct.

The entire street network is served by only one street along the east side of the plan.