Mixed-Use Development (MXD) Trip Generation

Current methods of traffic impact analysis, which rely on rates and adjustments from the Institute of Transportation Engineers (ITE), are believed to understate the traffic benefits of mixed-use developments (MXDs) and potentially overstate potential roadway impacts because they don’t fully account for the interactions between land uses or the surrounding built environment. A national study for the US EPA, performed by a team composed of Fehr & Peers and academic researchers developed a new methodology to more accurately predict the traffic impacts of MXDs. The study evaluated household travel surveys from 239 mixed-use developments in Seattle, Portland, Sacramento, Houston, Atlanta and Boston and found statistical relationships between site characteristics and the amount of vehicle travel generated in and out of the site. MXDs were found to reduce traffic impacts relative to single-use suburban development, due to the following key factors.

Diverse on-site activities that capture a large share of trips internally.
Placement within walkable areas with good transit access that generate high shares of walk and transit trips.
Central locations that reduce trip lengths.

The potential vehicle trip reductions from MXDs were significant enough to demonstrate that conventional trip generation methods could exaggerate roadway impacts and the need for mitigation including higher impact fees, exactions, and negotiated payments than should be the case. These factors could also contribute to potentially discouraging development of otherwise desirable projects.

What are the BMPs?

The acronym BMP (Best Management Practices) is replacing TSM (transportation system management), TDM (transportation demand management) and TCM (transportation control measures) to describe the familiar list of strategies to minimize transportation impacts, fuel consumption and emissions. It includes the usual network management, auto trip reduction incentives and pricing strategies to reduce VMT while preserving quality of service.

Why are they important?

1. SB375 Requirements: Based on the recommendations of the SB 375 Regional Targets Advisory Committee (RTAC) all 18 California MPOs will begin developing a list of integrated land use and transportation BMPs in early 2010 to accompany their GHG target proposals under SB 375.  But it’s more than the simple list. The RTAC recommended to ARB that the BMP be converted into an analytical spreadsheet tool to estimate reductions from a specific strategy or set of strategies in a particular setting. This would allow MPOs and local jurisdictions to make GHG reduction policy choices based on available research and empirical studies on the likely impacts on VMT and GHG reductions.
2. Other Requirements: AQ conformity issues, CEQA review protocols
3. Aspirations: energy conservation, health and safety, mobility vs. v/c ratio, green marketing, market expansion (aging demographics, other “choice” and dependent groups)
4. $$ Motives: state and regional funding incentive programs, federal funding for “livability” criteria, reduced infrastructure

Fehr & Peers BMP Projects
Through conducting a comprehensive literature review, discussing with BMP experts, and coordinating with the Air Resources Board, Fehr and Peers identified a prioritized list of transportation-related GHG reduction measures, assessing the effectiveness of each measure, and quantified the vehicle miles traveled (VMT) and GHG reduction potential.  A standard methodology and approach to calculate baseline unmitigated emissions was also developed.  The result of this work is a statewide guidebook for CAPCOA to reference in the review of development projects in the CEQA process.

Caltrans has just approved for release “Smart Mobility 2010: A Call to Action for the New Decade”. According to Caltrans Director Randell Iwasaki, the handbook represents “a new approach to integration of transportation and land use that addresses long-range challenges and provides short-term pragmatic actions to implement multimodal and sustainable transportation strategies in California.”

Smart Mobility 2010 provides practical tools and performance-based metrics to evaluate the goals of the Governor’s Strategic Growth Plan, the California Transportation Plan, and bond program projects. The document coordinates land use “place types” with modified transportation performance measures, to guide transportation decisions in a manner that accommodates future growth equitably, respects the environment, and fosters a sustainable economy.

Jerry Walters and Carlos Hernandez of Fehr & Peers were featured speakers during the Boulder Committee of Colorado ULI – Growing Cooler. Their presentation was titled Growing a Cooler Boulder and can be found by clicking here.

For more information on ULI Colorado, click here.

Fehr & Peers is currently developing tools that will enable planners and engineers throughout California to plan for sustainable growth. The tools will help the state’s Metropolitan Planning Organizations perform integrated transportation and land use planning studies and to prepare their Regional Transportation Plans and Sustainable Communities Strategies as required under California’s landmark climate change laws AB 32 and SB 375. A closely related effort will support environmental impact assessments for smart growth development projects in California, possibly setting a precedent for similar approaches nationally.

The work is sponsored by Caltrans, and involves the University of California at Davis and the Sacramento Area Council of Governments (SACOG), as well as Fehr & Peers. The studies draw upon Fehr & Peers’ experience with the US Environmental Protection Agency developing 4D models for regional blueprint planning and MXD methods for reliable quantification of travel generation impacts of mixed-use development and other forms of smart growth. The resulting tools will improve community and regional planning by cities, counties and regional planning agencies, as well as traffic impact studies of development projects. They will create better approaches to:

• Land use/ transportation planning, by enhancing the responsiveness of interactive visioning tools such as iPLACES and UPLAN to development density, diversity, design and other “D” factors
• Travel forecasting, through similar “D” refinements to output from travel demand models
• Development impact analysis, including CEQA documents, through “D” adjustments to methods used for estimating project traffic generation

Fehr & Peers role includes literature review, research, and development of mathematical models, pilot tests and implementation of vision tools and forecasting models in eight representative regions throughout the state, as well as development of user-friendly impact analysis tools for traffic engineers and environmental planners to inform infrastructure decisions and to address climate and energy sustainability.

Jerry Walters, member of the SB 375 Regional Targets Advisory Committee, reflects on what the committee recommendations mean for transportation and land use planning in California in 2010 and beyond

The SB375 Regional Targets Advisory Committee has completed its mission; may it rest in peace.  Save a single-event return engagement next spring to consider the results of MPO scenario planning and target testing, the RTAC’s job is done.  As of its September deadline, the 21 member panel had finished its statement on methods through which the California Air Resources Board should set 2020 and 2035 greenhouse gas (GHG) targets for each of the State’s major regions. 

As a member of the RTAC, I had the opportunity to directly engage with elected officials, directors of the State’s major MPOs,  representatives of cities and local transportation agencies, business and development interests, environmentalists, public interest representatives,  and academics in a highly technical yet highly political effort to help mold California’s economic and environmental future.  It was exhilarating at times and grueling at others, but I am proud of the results.  Critical decisions and recommendations were reached, most of them unanimous and all by consensus on issues ranging from:

• Interregional consistency, but flexibility and sensitivity to local differences,
• A collaborative bottom-up process for the regions to advise ARB on ambitious but achievable Statewide targets,
• Technical methods and a continuous improvement program to developing better models and information,
• Tools to convey strategy options and their effects in non-technical terms and to engage the public and elected officials in the process,
• Guidelines for addressing the role of the economic crisis, funding shortages, social equity, and co-benefits of climate and energy actions, and
• Performance monitoring

The full 68-page report is available by RTAC Report – click here.  Excellent summaries, produced by the League of California Cities, are located here.   Two points of clarification I offer on the LCC summaries are illustrative of key RTAC recommendations:

Concerning a region’s opportunity to take credit for improvements to vehicle fuel efficiency and cleaner-burning fuels the RTAC found that:

• SB 375 requires ARB to account for improved vehicle emission standards, changes in the carbon-intensity of fuels and future measures to reduce greenhouse gas emissions from these sources when setting the statewide targets. So region’s can not individually claim credit, but
• It is appropriate for MPOs to use, with sufficient documentation, transportation sector GHG reductions such as electric-vehicle subsidy programs and vehicle retirement incentives that go beyond the benefits from State and federal actions to meet their target and receive credit for local/regional innovation.

Concerning creating a level playing field for early achievers and late starters and dealing with the role of the economic downturn, the report recommends the target be based on a percentage reduction against a 2005 benchmark for each region’s individual  GHG per capita.  This gives regions credit for their achievements up to 2005 by reducing the amount of GHG per capita that those early-actors need to reduce (but not the percent).  Fixing the date at 2005 also avoids building into the targets abnormal and (we hope) temporary effects of the economy in employment, home sales, spending and travel.  The State and regional forecasts of population and jobs in 2020 will take into consideration the economic downturn, so the amount of GHG reduction that will need to be accomplished in 2020 will likely be less than it would have been under more normal 2005-to-2020 growth rate.

So what perspective does my 9-month RTAC service give me on the near-term role of California transportation planners in addressing climate challenge?  I have three suggestions:

1. Engage with MPOs, cities and counties, developers, business, and the public in the concentrated MPO blueprint-style scenario planning process in early 2010.
2. Anticipate the State Proposition 84 grants that will be available in 2010 for sustainable general plans, specific plans, community plans, and zoning ordinances
3. Prepare for a new era of performance evaluations on integrated land use and transportation strategy plans at both the regional and local levels, with strategies emphasizing best management practices, and with performance metrics focused fuel conservation, carbon emissions reduction, and co-benefits to the economy, social equity and public health.  
4. Cities and counties should update their general plans to incorporate GHG reduction goals.  These updates need to consider how GHG reduction goals should be balanced against other community values.  

As demonstrated by this video, nothing says “my message is important” like good production capabilities. Whether you like the message or not, it is hard not to like the messaging.

Ron Milam recently spoke at the League of California Cities, City Attorney Conference in Los Angeles, CA.  He was invited to present at the conference to explain the changes in California transportation modeling and planning in response to climate change and greenhouse gasses.  His presentation covered how the transportation planning paradigm is shifting in response to the new focus of climate change. 

“Ron’s presentation provided specific tools that all communities can use in addressing the challenges of climate change. City Councils, planning commissions, and public works and planning departments all will benefit from understanding the constraints of traditional modeling approaches and the opportunities presented by new tools to make modeling more useful,” Said Richard Taylor, Attorney for Shute Mihaly & Weinberger, and attendee of the City Attorneys conference.