VIEWS: 6 PAGES: 50 POSTED ON: 8/14/2011
Sprawl and Urban Development Nonurban Sprawl • The county’s growth rate is in the upper quartile of the “economic area’s” annual county household and employment growth rates • The county’s growth rate exceeds the average annual national county growth rate • The county’s absolute level of growth exceeds 40% of the average annual absolute county growth. Urban Sprawl Defined • The landscape sprawl creates has four dimensions: – a population that is widely dispersed in low-density development; – rigidly separated homes, shops, and workplaces; – a network of roads marked by huge blocks and poor access; and – a lack of well-defined, thriving activity centers, such as downtowns and town centers. • Most of the other features usually associated with sprawl - the lack of transportation choices, relative uniformity of housing options or the difficulty of walking - are a result of these conditions. Measuring Sprawl Objectively • Based on this understanding, the researchers set about creating a sprawl index based on four factors that can be measured and analyzed: – Residential density; – Neighborhood mix of homes, jobs, and services; – Strength of activity centers and downtowns; – Accessibility of the street network. • Each of these factors is in turn composed of several measurable components, a total of 22 in all. Residential Sprawl • The places where housing is most spread out include a number of medium-sized metro areas in the southeast. • These are places where growth has mostly occurred during the automobile era, and have been without topographic or water related constraints that otherwise restrict development. • The prevalence of low residential densities in this particular region is striking and merits further investigation. Neighborhood Mix of Homes, Shops, and Offices • One of the characteristics of sprawl is the strict segregation of different land uses. In sprawling regions, housing subdivisions are typically separated—often by many miles—from shopping, offices, civic centers, and even schools. • This separation of uses is what requires every trip to be made by car, and can result in a “jobs-housing imbalance” in which workers cannot find housing close to their place of work. • More traditional development patterns tend to mix different land uses, often placing housing near shops, or offices above storefronts. • Measuring the degree of mix is therefore an important descriptor of sprawl. Comparison of Low-Density Sprawl With New Urbanism Strength of Metropolitan Centers • Metropolitan centers are activity centers that help businesses thrive and support alternative transportation modes and multipurpose trip making. • Connectedness can be represented by concentrations of employment or population. • It can also represent a single dominant center or multiple subcenters. Lessons from The Most Sprawling Metro Regions • The most sprawling metro area of the 83 surveyed is Riverside, California, with an Index value of 14.22. It received especially low marks because: – it has few areas that serve as town centers or focal points for the community: for example, more than 66 percent of the population lives over ten miles from a central business district; – it has little neighborhood mixing of homes with other uses: one measure shows that just 28 percent of residents in Riverside live within one-half block of any business or institution; – its residential density is below average: less than one percent of Riverside’s population lives in communities with enough density to be effectively served by transit; – its street network is poorly connected: over 70 percent of its blocks are larger than traditional urban size. Impacts of Sprawl on Travel What is a Growth County? • Have Maintained Double-Digit Rates of Population Growth for Each Census Since 1950 • Are Located in the Nation’s 50 Largest Metropolitan Areas as of the 2000 Census • Come in Three Sizes: – “MEGA” Over 800,000 People – “Edge” Between 200,000 to 800,000 People – “New Metropolis” Under 200,000 People • BoomBurb Three Types of Growth Counties • MEGA Counties - 23 massively enlarged, growth- accelerated counties with a total population of 37 million • Edge Counties – 54 areas mostly at or near the edge of their regions and often at the leading edge of metropolitan growth with a total population of 20.8 million. • New Metropolis Counties – 47 counties lying mostly at the regional fringe, generally do not contain large concentrations of commerce, and are updated versions of bedroom suburbs with a total population of 4.7 million. MEGA Counties • Found mostly in booming regions of the Sunbelt. – Harris County, TX - Maricopa County, AZ – Travis County, TX - Palm Beach, FL – Orange County, CA - Broward County, FL – Clark County, NV - Miami–Dade County, FL – Santa Clara County, CA - Travis County, TX – Fairfax County, VA - Santa Clara County, CA – Maricopa County, AZ - Dallas County, TX • They can be big suburban counties outside the nation’s largest cities • Now perhaps as important to the nation’s commerce as any of its large traditional cities. • Home to many of the largest office centers in the nation that lie outside of a central business district Edge Counties • Typically contain “Edgeless Cities” which are a form of sprawling office development that never reaches the densities or cohesiveness of Edge Cities (mostly isolated office buildings at varying densities over vast swaths of metropolitan space). • Older metropolitan areas have high-density traditional cores and rings of older, pedestrian-oriented suburbs, they also feature new, so-called sprawling growth, which is often found in Edge Counties. • Edge Counties are growth engines because in many of these older regions they account for a majority of new people added despite often containing just a small share of the total metropolitan population. New Metropolis Counties • So-named because they are new to their regions - having been added to the official metropolitan statistical area after 1971. • They reflect the new metropolitan growth pattern - they are all low-density, centerless, and sprawling. • The New Metropolis Counties may be Edge Counties in formation. • Residents of New Metropolis Counties often work in Edge Counties, which means that more commutes are originating in what were once rural areas. • Thus, commercial development in Edge Counties fuels the emergence of New Metropolis Counties, which in turn promotes even more population growth farther and farther from the regional core. • New Metropolis Counties are the new suburbs of suburbs, which in the future may spawn even more distant suburbs. Boomburbs • A boomburb is a large, rapidly growing city that remains essentially suburban in character even as it reaches populations more typical of urban core cities. • A boomburb is an area that currently has more than 100,000 residents and has maintained double-digit rates of population growth in each recent decade, but is not the largest city in its metropolitan area. • Boomburbs almost never have a dense central business area. • And their housing, retail, entertainment, and offices are spread out and loosely configured. Boomburbs • They're located in 14 metro areas surrounding Phoenix, Los Angeles, San Diego, San Francisco, Denver, Miami, Tampa, Chicago, Las Vegas, Portland, Dallas, Salt Lake City, Norfolk and Seattle. • Boomburbs range from Mesa, Ariz., with nearly 400,000 residents, to Westminister, Colo., with just over 100,000. 1989 2009 On the southeastern outskirts of the Phoenix metropolitan area, Chandler grew from just 3,799 residents in 1950 to 176,581 residents in 2000, based on 10-year census figures. The differences between these images indicate that a significant portion of that growth happened after 1989. 1989 Florida Growth Pattern Study: Capital Facility Costs Under Sprawl Versus Compact Development (per dwelling unit; 1990 dollars) Comparison of Residential Densities on Costs & Revenues Monterey County, CA 2002 Built Environment Effects to Travel Behavior (Ewing and Cervero, 2002) REGIONAL EFFORTS TO CONTROL URBAN FORM • Inasmuch as land use planning is usually at the center of regional planning, regional planning efforts usually focus on how the urban area could look different than it would have otherwise. • The desired difference is usually in the direction of more centers and density. • At the regional level, the options for urban form are few in theory and in practice. For any predicted amount of growth, a region can – (1) continue what has in U.S. cities been a universal pattern of suburbanization (residential growth accommodated in relatively low density development, primarily at the urban fringe); – (2) try to get that growth to concentrate more in the central city and major subcenters within the existing metropolitan area (urban growth boundaries); or – (3) deflect the growth to satellite cities not contiguous to the metropolitan area. Comparing and Evaluating Metropolitan Regions • Some metro areas were found to sprawl badly in all dimensions. These include Atlanta, Raleigh and Greensboro, NC. • A few metros did better than other regions in all four factors; among them are San Francisco, Boston, and Portland, Oregon. • Other metro areas are more of a mixed bag; in those cases, the individual factor scores can tell us more about the characteristics of individual metro areas. For example, while the Columbia, SC or Tulsa, OK metro areas contain large swaths of low-density development, the presence of a number of strong centers bring them up in the overall ranking. • And while San Jose, California, has slightly higher density than most metro areas, its lack of centers of activity pulls it down in the overall ranking. Sprawl’s Impact on Quality of Life • Higher rates of driving and vehicle ownership. • Increased levels of ozone pollution. • Greater risk of fatal crashes. • Depressed rates of walking and alternative transport use. • No significant differences in congestion delays Alleged Negative & Positive Impacts of Sprawl Markets Where Policies to Change Urban Form are Likely to Have Direct (Internalized) Effects on Prices • This figure shows the hypothesis that the main effects of a change in form should be captured through changes in the costs of providing infrastructure services. • An important and defensible assumption is that the effect of urban form on households, businesses, and governments occurs mainly through a derived demand for infrastructure, an intermediate good. • The conclusion is that the impact of changes in urban form on the cost of infrastructure is probably the single most important impact to evaluate. • That approach, with infrastructure as the sole concern, does not cover everything, either technically or politically. Sprawl and Health Concerns • Because this study is ecologic and cross-sectional in nature, it is premature to imply that sprawl causes obesity, hypertension, or any other health condition. • Our study simply indicates that sprawl is associated with certain outcomes. • Future research using quasi-experimental designs is needed to tackle the more difficult job of testing for causality. “Relationship Between Urban Sprawl and Physical Activity, Obesity, and Morbidity” by Reid Ewing, Tom Schmid, Richard Killingsworth, Amy Zlot, Stephen Raudenbush in the American Journal of Health Promotion, Inc., September/October 2003, Vol. 18, No. 1 Sprawl, Weight and Blood Pressure Sprawl & Obesity Policy Recommendations for Regions Wishing to Reduce Sprawl 1. Reinvest in Neglected Communities and Provide More Housing Opportunities 2. Rehabilitate Abandoned Properties 3. Encourage New Development or Redevelopment in Already Built Up Areas 4. Create and Nurture Thriving, Mixed-Use Centers of Activity 5. Support Growth Management Strategies 6. Craft Transportation Policies that Complement Smarter Growth Selected Statistics On Urban/Suburban Density & Growth In 15 MSAs, 1990–2000 Population Per Square Mile Statistics MSA 2000 Density Little Rock-N. Little Rock 201 Syracuse 238 Rockford IL 239 Normal(675.26, 399.60) Chattanooga 255 1.8 Knoxville 281 Nashville 302 1.6 Memphis 378 Portland-Vancouver 382 1.4 New Orleans 394 Sacramento 399 Values x 10^-3 1.2 St. Louis MO 407 Jacksonville 418 1.0 Charlotte-Gastonia-Rock Hill 444 Minneapolis-St. Paul 490 0.8 Pittsburgh 510 Seattle-Bellevue-Everett 546 0.6 Denver 561 Dayton 565 0.4 Dallas 569 Ft. Worth-Arlington 584 0.2 Atlanta 672 Houston 706 0.0 Buffalo-Niagara Falls 747 Washington DC 756 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 Salt Lake City-Ogden 825 Values in Thousands Cleveland-Lorain-Elyria 832 Tampa-St. Pete-Clearwater 938 < 0 % 9 .0 .0 5 % > Baltimore 979 .0 8 0 1 .3 3 1 3 Detroit 1,140 New Haven-Bridgeport-Stamford 1,261 Source: U.S. Census Bureau Newark 1,289 San Jose 1,304 Statistical Abstract of the United States, 2002 Oakland 1,642 San Francisco 1,705 Median Central City Employment Statistics MSA % CC Emp Newark 10.44% Pittsburgh 13.88% Tampa-St. Pete-Clearwater 14.66% Oakland 15.09% Normal(0.32440, 0.18489) Salt Lake City-Ogden 15.62% 4.0 Dayton 15.65% Detroit 16.16% Cleveland-Lorain-Elyria 17.39% 3.5 Syracuse 20.00% New Haven-Bridgeport-Stamford 20.39% 3.0 Baltimore 21.04% Buffalo-Niagara Falls 24.02% 2.5 Washington DC 24.25% Denver 24.39% 2.0 Sacramento 24.77% Seattle-Bellevue-Everett 25.51% Portland-Vancouver 25.63% 1.5 Knoxville 26.14% Ft. Worth-Arlington 29.82% 1.0 Atlanta 31.13% New Orleans 32.15% 0.5 Little Rock-N. Little Rock 32.65% Chattanooga 33.38% 0.0 Charlotte-Gastonia-Rock Hill 37.18% Rockford IL 37.82% 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 St. Louis MO 41.83% San Francisco 43.83% < 0 % 9 .0 .0 5 % > Nashville 45.99% .0 0 0 2 .6 9 0 2 Houston 46.82% San Jose 50.55% Source: US Census Bureau data Memphis 55.78% www.demographia.com Jacksonville 65.84% Dallas 66.34% Minneapolis-St. Paul 96.84% Median Exurban Living Comparing Sprawl and Smart Growth Surface Coverage of Different Land Use Classes Automobile Contributions Toward Sprawl Household Annual Municipal Costs by Residential Densities Transportation Costs That Increase with Sprawl Annual Household Auto Costs Under Four Densities Sprawl – A Reprise • Automobile dependency has a number of negative land use impacts. • It increases the amount of land paved for roads and parking which has economic, social and environmental costs. • Automobile oriented cities devote up to three times as much land to roads and parking as traditional, pedestrian-oriented cities. • Automobile dependency tends to result in lower density, urban periphery development (sprawl), which imposes a number of economic, social and environmental costs. • Sprawl increases the amount of land used per capita for roads, parking, and buildings and reduces the land left for agricultural and wildlife habitat. • Under most conditions it increases costs for public services.
Pages to are hidden for
"Sprawl and Urban Development"Please download to view full document