A Brief Introduction to Pavement Design: A Fifteen Minute Writing Exercise

According to Southworth and Ben-Jospeh in Streets and the Shaping of Towns and Cities, roads, parking lots and other automobile related infrastructure count for 50% of land use in most U.S. cities. Roads date back to Roman times. Whereas the idea of engineered roads was introduced approximately 200 years ago. In the U.S., the majority of the roads have been built. Engineers are now focused on the management and maintenance of our already existing infrastructure.

Pavement is an engineered structure on the ground that facilitates the movement of goods and people. Pavement is implemented for all weather mobility for higher safety, efficiency and fuel economy. Pavement design can have a huge impact on the environment, energy consumption, connectivity, labor, maintenance, etc. There are many different types of pavement, some dirt roads are coated with one thin layer of pavement to increase fuel economy by reducing rolling resistance. Coating dirt also helps decrease dust and noise. Other pavements are very thick, like the deep pads used for rail road subsurface.

The pavement subsurface helps displace the load from vehicles or trains. The majority of the damage to roads comes from trucks. A truck traveling down the interstate is similar to the damage inflicted by 5,000-10,000 sport utility vehicles. Trucks are limited to 40,000 ton carrying capacity due to safety and stopping distance. More damage is done to the roads when trucks implement high tire pressure or have less tires to displace the load. However, there are trade offs. If trucks were able to carry 10% more weight, green house gas emissions would decrease due to efficiency.

I Choose, Therefore I Walk (Bike, Bus, Drive...)

Do people walk down unpleasant streets, bike on roads without a bike path and drive when they do not have to? Sure, this occurs everyday. The notion that people drive more in the suburbs and walk more in the city is now complicated by the idea of choice. Granted accessibility and income largely dictate transportation mode choice, new studies by Handy and Mokhtarian, "Which comes First: The Neighborhood or the Walking?" question the causes for such outcomes. Do people that like to walk more simply move to walkable neighborhoods? If so, this challenges the built environments' role in creating walkable neighborhoods. Conversely, if driving is ingrained behavior or people's preference, would it really matter if goods were accessible? Would people still drive? What is your attitude about travel and what would it take to change your behavior?

Go L.A.!

CicLAvia, Let’s Go! from Streetfilms on Vimeo.

When Bicycling Dreams turn into Doubt

The last thirty-six hours have presented a watershed of events, exposing raw bicycling karma. Tuesday I was left by the cycling team on a no drop ride miles from town. Last night, I was nearly hit by a Mustang rolling through a stop sign downtown and this morning, honked at for merging to make a left turn.

If, in a place like Davis, a platinum rated bicycle city, cannot escape angry drivers rolling through stop signs and motorists honking horns, in the belief of a slightest cycling error – what place is actually safe for cyclists? Motorists are not the only culprit, cyclists ride erratically in bicycle lanes, fail to signal or stop at stop signs and oppress the pedestrians to a level of absurdity on campus. I moved 2,700 miles to be mowed down by a barrage of cyclists entering a roundabout on the UC Davis Campus. . .

Is safe cycling an oxymoron? Are we asking for too much, to share a sliver of the road and have the ability to make left turns, safely reaching our destination and becoming an integral part of the urban fabric? Is safe cycling synonymous with Moore’s Utopia, brilliant on paper and yet a fallacy? If Davis is the best for cycling, then why do so many people still drive, and further more – why is it still unsafe to ride a bicycle?

Introduction to Traffic Flow, Control, and Capacity: A Fifteen Minute Writing Exercise

Vehicle infrastructure encompasses a variety of road types including: interstate, arterials and neighborhood streets. Each has different characteristics with varying capacities for congestion. The design of each type is different for the variety of uses.

Congestion is a major challenge in transportation planning. The problem is peaking, where massive amounts of vehicles travel at the same time of day, during morning and evening rush hour. There may not be enough capacity at that time of day, however, the infrastructure cannot be built to provide just for the highest peaks. Infrastructure is already overbuilt in most parts of the country. And, congestion can be a good measure for economic productivity and population growth. Although, congestion should be avoided when excessive.

A road’s capacity is based on the maximum flow, or people passing in a unit of time. Weather impacts speeds as well as drivers and vehicle type. A road’s design largely impacts the flow of traffic. Wider lanes lend faster traveling speeds. Topography also plays a role, in flat broad areas, speeds tend to be higher. On the interstate, 2,200 to 2,400 vehicles are able to pass per lane per hour.

On local arterial roads, streets intersect at grade. Some arterials meet at lights or stop signs whereas others may join in a roundabout. Roundabouts may not necessarily be safer for pedestrians or cyclists, because they keep traffic moving. When there is not enough demand at street junctures, a stop sign is placed. When traffic warrants a signal, signals are installed using a variety of techniques to determine signal length and configuration. Some signals are fixed, meaning the timing does not change. Whereas others are semi-activated, where major and minor streets join. Fully activated signals have sensors on each major intersection to direct traffic appropriately. Some signals are coordinated through signal optimization, which considers the speed of the vehicles and block length in order to keep traffic moving.

The Alphabet of Opposition – NIMBYs, LULUs and NOPEs Oh My!

While reviewing Matthew J. Kiefer’s assessment of NIMBYism, I had to ask myself a David Byrne inspired question, “How did we get here?” With a list of acronyms that carries on to infinity, one may need a lexicon to wade through land use planning decisions. The interesting concept is how people move so often, upgrade and remodel the insides of their homes but then adamantly oppose any change within their community or surroundings. Kiefer mentions that the average America moves twelve times in their lives. Residents fail to accept that change will occur. All the dwelling we reside in were built at some point, changing the initial landscape. So then, when a group opposes change, demanding that it stays the same – define the same. Maintaining the urban fabric of what time period? Are we seeking pre-war era, the City Beautiful Movement, agrarian based villages? Or are we simply chasing our tails in the hopes that we do not have to let go of the things we cherish most about where we live? Is the same, defined as the horizon of the setting sun, an imaginary line continuously moving? Civic engagement has a point, to protect residential areas from imposing industrial degradation, to provide environmental justice and so on. But at some point, a meeting of the minds must occur, and communities must learn that compromise is not a four letter word.

Don't try this at Home

inspired?

Travel Demand and Behavior – Asking “Why People Travel?” : A Fifteen Minute Writing Exercise

Travel demand and behavior examine different phenomena. Both deal with personal choice but differ in many ways. Travel demand is examined at the aggregate or system wide level. Travel demand is used to forecast the future. Travel planners in the Bay Area, for instance, study travel demand to predict the future use and load on the current infrastructure. Where as travel behavior is more local, measured by individual, household or vehicle. Travel behavior studies aim to measure the attitudes and their impact on selection, flexibility and conveniences of a population. A transportation behavioralist may ask “why do people drive versus take the subway?”

So why do people travel? First, people travel because there is a demand to be in different places. People travel to be where they need to be. In this instance, travel is defined as a disutility, something people want to minimize. Second, people travel because they may enjoy traveling, like a road trip versus taking the train. People may enjoy the act of driving. Also, people travel for personal recreation or exercise. Many go on vacation to ski or hike. People inherently like to move and be mobile. Other hobbies include horseback riding, bicycling, running, etc.

Modeling is often used to untangle complex scenarios. Transportation demand forecasting is the workhorse for most metro areas. Modeling can be based on a variety of data, including large-scale travel and activity diary surveys. Diaries entries contain information like whether the participant traveled, where they went, by what means, and which route. Modeling can also factor attitude and opinion of traveling.

London's High Design for Streets

Traffic Calming: Postcards from London from Streetfilms on Vimeo.

Critiquing the West Baltimore MARC Transit-Centered Community Development Strategy

The West Baltimore MARC Transit-Centered Community Development Strategy (The Strategy) is a framework document providing guidance for the revitalization of the areas within a half-mile of the current West Baltimore MARC station over the next 35 years. The Strategy proposes the creation of a transportation oriented development centered around the West Baltimore Station, located at Franklin and Pulaski Street, that consists of east and west bound platforms and two parking lots. Designed with heavy public involvement, the Strategy aims to improve the areas by targeting three principals: housing, economic and transportation. The Strategy “is not intended to be the last word on how West Baltimore is redeveloped – rather it is intended to be the first” (City of Baltimore Department of Planning 11).

Typical of most urban areas, West Baltimore’s population declined after World War II due to a variety of reasons: white flight, suburbanization, job loss, etc. Historic race riots occurred throughout Baltimore in1968 stemming from the assassination of Reverend Martin Luther King Jr. Many communities have not rebounded from these events. The Strategy targets communities around the West Baltimore MARC station including: Bridgeview & Greenlawn, Midtown Edmondson, Station West (Penrose), Shipley Hill, Franklin Square, Boyd-Booth, Harlem Park, and Rosemont. Neighboring communities include Union Square and Carrollton Ridge. Based on the 2000 Census, the surrounding communities are roughly 99% African American, largely consist of families and the working class (City of Baltimore).

Local stakeholders include Coppin State University, Baltimore City, Acme Industrial, Bon Secours Hospital, the Maryland Transportation Administration and the residents within the surrounding communities. Public involvement gained momentum throughout the planning process. The first workshop held in 2006 consisted of a week long community planning charrette that led to the creation of the West Baltimore Coalition (WBC), a group of community stakeholders. The WBC recruited neighborhood residents and held monthly meetings to establish direction and specific interest. Also, the WBC distributed flyers to every residence within a half-mile of the MARC station notifying the public about involvement in the upcoming workshop. A second workshop was held in October 2007 and the community developed one goal, “use the MARC station and other transportation improvements to create an affordable neighborhood that is full of residents, shops, restaurants, civic amenities, parks, and other recreational opportunities” (City of Baltimore Department of Planning 18). In November 2007, residents gathered to agree on concepts that are “needed to make West Baltimore a better place to Live, Earn, Play and Learn,” and thus creating the outline for the Strategy (City of Baltimore Department of Planning 18).

The Strategy outlines methods to improve housing, economic development and transportation. Through all principles, each seeks to draw investments to the community. The community also desires greater connectivity to “jobs, schools, medical centers, retailers, and other areas of the city” (City of Baltimore Department of Planning 13). The Strategy plans to achieve all these goals through small-scale infill projects that are sensitive to the already existing community.

The key housing principles include stabilizing current housing stock and avoiding the displacement of current residents by making housing affordable. The Strategy aims to increase housing stock but also preserve the historic character of existing infrastructure. Diversifying the housing stock is also important to create a variety of places to live for different lifestyles. There is a large amount of abandoned housing and the Strategy has identified sensitive infill for these areas.

The community hopes to draw large-scale economic redevelopment into the surrounding area, foster businesses that would serve the local population and provide employment opportunities. Small business development is also encouraged. Redevelopment opportunities include the redesign of the Ice House, a large industrial building adjacent to the MARC station, which could be used as shelter for passengers with restaurants and retail potential. The Warwick industrial triangle, within walking distance to the station, also has similar mixed-use potential.

The transportation principle seeks to use the MARC station more fully and improve alternative transportation modes within the community. “Approximately 60 percent of area residents do not have access to private vehicles,” and rely heavily on the local transit network (City of Baltimore Department of Planning 35). The Strategy makes an emphasis on improving the bicycling and pedestrian environment with new transportation plans that focus on complete streets and traffic calming. Under the transportation principle, the community wishes to dismantle Route 40, known as the “highway to nowhere,” and revitalize the area into a “highway to somewhere,” a tree-lined boulevard with access to the proposed Red Line with high economic potential. The new Red Line, an east to west light rail, proposed a station in West Baltimore. The Red Line would connect West Baltimore to the already existing Baltimore Metro and Light Rail downtown. There is speculation regarding the Red Line, however, its implementation would help create a destination place in West Baltimore.

The Strategy does not explicitly review the financing for the proposed redevelopment, leaving one to ask, “Where will the money come from?” The Strategy may be more convincing if other constituencies were identified that are not currently in West Baltimore. Funding could be generated from paid parking spaces to pay for sidewalk upgrades etc. Identifying the financing options would strengthen the likelihood of implementing such a plan.

Also, the Strategy does not cover the issue of crime. Baltimore City has some of the highest crime rates in the Nation. Within the City, crime is disproportionately located in pockets of East and West Baltimore. Crime is a major impetus to reinvestment in West Baltimore and a difficult hurdle to surmount. The crime stems for deep seated and complex socio-economic problems resulting in high levels of drug and gang related violence. Reinvestment might help quell the violence, but more than likely, the community will have to improve first.

Overall the Strategy is opened minded and flexible to a “range of possible futures” (City of Baltimore Department of Planning 40). In the current economic times, investors may be scarce. However, working with the public and outlining the framework provides a vision for future and marks the starting point. In the meantime, the Strategy could take advantage of existing bus lines and public involvement to clean up the community. The dismantling of Route 40 is currently underway, which will greatly enable development along the corridor. The Strategy is well rounded, not simply improving things for motorists or commuters, but has the potential to make things better in the community and change people’s lives.

City of Baltimore. "City of Baltimore Planning / Research and Data." City of Baltimore, Maryland - Official Website. 2010. Web. 01 Oct. 2010.
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City of Baltimore Department of Planning. "West Baltimore MARC Station Master Plan." City of Baltimore, Maryland - Official Website. Nov. 2008. Web. 01 Oct. 2010.
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Photo Courtesy of John Perivolaris