Jacquelyn Bjorkman

Regional Assessment of Urban Impacts on Landcover and Open Space Finds a Smart Urban Growth Policy Performs Little Better than Business as Usual

Assessment of landscape change is critical for attainment of regional sustainability goals. Urban growth assessments are needed because over half the global population now lives in cities, which impact biodiversity, ecosystem structure and ecological processes. Open space protection is needed to preserve these attributes, and provide the resources humans need. The San Francisco Bay Area, California, is challenged to accommodate a population increase of 3.07 million while maintaining the region’s ecosystems and biodiversity. Our analysis of 9275 km2 in the Bay Area links historic trends for three measures: urban growth, protected open space, and landcover types over the last 70 years to future 2050 projections of urban growth and open space. Protected open space totaled 348 km2 (3.7% of the area) in 1940, and expanded to 2221 km2 (20.2%) currently. An additional 1038 km2 of protected open space is targeted (35.1%). Urban area historically increased from 396.5 km2 to 2239 km2 (24.1% of the area). Urban growth during this time mostly occurred at the expense of agricultural landscapes (62.9%) rather than natural vegetation. Smart Growth development has been advanced as a preferred alternative in many planning circles, but we found that it conserved only marginally more open space than Business-as-usual when using an urban growth model to portray policies for future urban growth. Scenarios to 2050 suggest urban development on non-urban lands of 1091, 956, or 179 km2, under Business-as-usual, Smart Growth and Infill policy growth scenarios, respectively. The Smart Growth policy converts 88% of natural lands and agriculture used by Business-as-usual, while Infill used only 40% of those lands. Given the historic rate of urban growth, 0.25%/year, and limited space available, the Infill scenario is recommended. While the data may differ, the use of an historic and future framework to track these three variables can be easily applied to other metropolitan areas.

Experimentation and Innovation in Advance Mitigation: Lessons from California

Advance mitigation is a process through which the environmental impacts and required mitigation are assessed for one or more transportation projects early in project planning and development. The approach enables mitigation to be planned, commenced, and completed earlier; applies regionally or programmatically across multiple projects; and takes ecosystem- and landscape-level concerns into account. Although there have been efforts to develop programmatic mitigation initiatives and funding to support them, there is little documentation of their establishment, operation, or accomplishments. A study documents and analyzes 10 prominent California experiences with advance mitigation undertaken by the state department of transportation in coordination with regional councils, local governments and transportation agencies, and environmental groups. Each effort is profiled, including the origin of the mitigation effort; its location, scale, and cost; its specific connection to transportation projects; funding, revenue sources, or financial options used to support it; key institutional partners; and lessons learned from the experience. Californias initiatives offer some lessons: external conservation planning efforts can play a significant role in creating both momentum and structure for comprehensive mitigation planning; transportation-related advance mitigation is necessarily a highly interdependent undertaking, involving not only the state department of transportation and other transportation project sponsors but also federal and state natural resource agencies as well as local environmental groups; and the long-time horizons of advance mitigation planning and the complex nature of infrastructure development bring unavoidable uncertainty to such efforts and demand flexibility from mitigation partners in the process.