Category Archives: Academia

Freiburg’s Way

17 Thursday Dec 2015

Posted by in Academia, Germany, Land-Use, Parking, Planning, Transportation, Urbanism

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Freiburg, a small city in Germany has become one of the role models for sustainable urban development in affluent regions. Freiburg is located in a prosperous region in Germany (the state of Baden-Wurrtemberg) a nation known for its automobile production and use. Even so, during the last 50 years Freiburg has taken a myriad of urban planning and policy steps resulting in a rather low car ownership and low car dependence.

Last year, I was on a tour in Germany where we also visited Freiburg and its celebrated new sustainable quarter called Vauban. This area was an abandoned French military camp, which was reused and turned into a very low car mixed-use residential quarter. The place was re-built using strong platform of cooperation between residents and the city government incorporating all kinds of sustainable solutions including integrated land-use and transportation planning. Freiburg’s light-rail was extended to the Vauban quarter, while parking was heavily restricted. Besides the overall urban plan, Vauban includes many unique sustainable experiments such as the solar settlement consisting of 59 units which produce more energy then they consume, employing solar panels (surprise!).

In Vauban’s main street
The Main Street of Vauban

A paper titled “Sustainable Transport in Freiburg: Lessons from Germany’s Environmental Capital” and published at the “International Journal of Sustainable Transportation” sheds light on Freiburg’s path to sustainability, including several anecdotes and recommendations on what can be learned from the Germans’ experience. For example, it describes the way in which Vauban planners managed to avoid the 1:1 mandatory parking minimum ratio for residential developments in Germany:

After long negotiations, Vauban was granted a waiver for minimum parking requirements provided that enough green space was preserved for potential future construction of parking lots. Building permits in Vauban are issued for residential units without parking spots. Residents who decide to own a car can purchase a parking spot in one of the parking garages at the edge of the development for the equivalent of $25,000. Residents who wish to live car-free simply pay a one-time fee of $5,000 to preserve open space at the edge of the development— in lieu of a parking spot.

The authors also describe Freiburg’s streetcar decline and car use rise in the 1950’s and 1960’s which is similar to many other cities in the western world. Besides giving a comprehensive timeline on Freiburg’s sustainable urban planning decisions, the authors point out to an early event, a proposed nuclear plant in the 1970’s that helped form a partnership among many civic groups:

Moreover, during the early 1970s, the planned construction of a nuclear power
plant just 30km from Freiburg’s old town made environmental protection a critical issue (Hopwood 2007). Protests against the state government’s plan to build the nuclear power plant lasted for years and forged an unlikely alliance of leftist students, Catholic and Protestant church leaders, the conservative party, and local farmers. Highly respected civic leaders were at the center of the local opposition to the state government’s plan. Their role in the protests legitimized environmental protection and alternative development ideas for the local population (Chaney 2008;Hopwood 2007).Over the last 40 years Freiburg has developed a strong tradition of cooperation, negotiation, and consensus among city administration, citizen groups, and local businesses (Bratzel 1999). Public discourse, citizen participation, and cooperation paved the way for a gradual change towards sustainability in Freiburg (Bratzel 1999).

In the conclusion of the paper, seven lessons for implementing sustainable transport policies are specified as follows:

  1. Implement controversial policies in stages.
  2. Plans should be flexible and adaptable over time to changing conditions.
  3. Policies must be multi-modal and include both incentives and disincentives.
  4. Fully integrate transport and land-use planning.
  5. Citizen involvement must be an integral part of policy development and implementation.
  6. Support From higher levels of government is crucial to making local policies work.
  7. Sustainable transport policies must be long term, with policies sustained over time, for lasting impact.

It should be noted that Freiburg does not have a transportation planning division, but an integrated urban planning department that combines transportation and land-use planning. This is probably the easiest recommendation to implement (number 4 above) – abolish municipal transportation departments and merge them inside land-use planning. The city keeps growing at a modest pace and is currently planning a new quarter for 10,000 people which will probably rise to new fame when its built.

You can read the full paper on Freiburg’s sustainable urban development here.

Pedestrian Movement and the Built Environment in One Simple Diagram

28 Wednesday Oct 2015

Posted by in Academia, Israel, Land-Use, Tel Aviv, Transportation

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Following the previous post which discussed actual observed pedestrian movement and commercial streets in Tel Aviv, we now turn to the major theoretical contribution we made in our last paper regarding the connection between the built environment and pedestrian movement.

In order to understand the connection between pedestrians and urban environment we have quantified a lot of built environment features. Those variables were divided into four different dimensions:

  1. A spatial dimension. This dimension is related to the structure of the road network, meaning the basic urban space mainly consisting of streets and squares. This dimension of the built environment is relatively stable and does not change. Various studies have already shown the importance of the street network configuration to pedestrian movement as well as other urban dynamics.
  2. A functional dimension. This dimension relates to land use and we included in it the distribution of retail fronts and proximity to public transit.
  3. A physical dimension. This dimension is related to actual street sections, meaning the width of the sidewalk and carriageway, which determines how easily a pedestrian can cross a street.
  4. A demographic dimension. This dimension is related to residential and employment densities.

While conducting this study I have spent numerous hours doing field surveys to map all kinds of missing data. Specifically, retail fronts locations as well as road and pavement widths are not easy to come by. As the age of Big and Open Data is fast approaching I hope that more types of data will be collected on a regular basis, leaving us with more time for analysis. After we have collected all the quantitative data we ran endless statistical correlations to better understand how the built environment and movement are tied together. The conclusions below are derived from the statistical connections we found.

Our study draws heavily on space syntax theory, which emphasizes the dominance of the street network structure on various urban dynamics. One of the best known papers in this field deals with the connection between urban space and pedesrtian movement. This paper from 1993, written by Bill Hillier and others describes the natural movement of people in urban space and connects movement, land use and street network structure.

Hillier offers the following diagram as a description of the interaction between movement and the spatial and functional dimensions. Hillier presents the argument that the spatial configuration is the basis of urban processes. He shows that the configuration can impact both movement and land use, but land use and movement cannot impact the spatial configuration. Movement and land use have a reciprocal connection, meaning that movement may induce retail development and that retail may in turn impact movement in its area. In the diagram below movement is marked with M, retail is marked with A (for attraction) and street network is marked with C (for configuration):

Hillier et al. (1993) pedestrian movement diagram

Original Hillier

Our findings are in line with Hillier’s diagram. Our theoretical contribution is an extension of Hillier’s diagram to include the physical dimension and add the urban area type (traditional vs.contemporary) as the basis of the generation of urban space itself.  The physical dimension was found to be impacted by the configuration and to have an impact on movement (similar to the functional dimension). Essentially, sidewalk width may change due to people movement and in turn change the movement pattern. In the diagram below you can see Hillier’s original triangle to the right and at the the top is the urban area type which impacts all the urban environment dimensions.

Lerman and Omer (2016) pedestrian movement diagram

DiagramForBlog

The next post will deal with specific finding and the struggle to find the best movement model for every city.

Where People Go and Commercial Streets Grow

26 Monday Oct 2015

Posted by in Academia, Israel, Land-Use, Planning, Tel Aviv, Transportation

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The next few posts will be dedicated to my PhD dissertation dealing with pedestrian movement in different urban contexts. The paper containing my dissertation’s major findings has been accepted for publication in the journal – “Computers, Environment and Urban Systems” – and for a limited time is available for free. The paper was written together with my advisor, Itzhak Omer, under the title:

Urban Area Types and Spatial Distribution of Pedestrians: Lessons from Tel Aviv

Essentially, this study aims to examine what conditions lead to greater pedestrian movement in urban space. To achieve this goal we have quantified various attributes of the built environment and then checked their statistical association with the level of observed pedestrian movement. The research was carried in four different areas in the city of Tel Aviv. Each of those areas was split into a traditional urban area and a contemporary one, reflecting the major shift that occurred during the 20th century in urban planning from a humanistic discipline to a technocratic one. In this sense Tel Aviv is an ideal case for such an investigation containing both contemporary and traditional urban areas in close proximity.

This post will focus on the observed pedestrian movement volume and the retail fronts distribution. First, let’s have a look at the chosen research areas and their division to traditional and contemporary urban areas. The map below shows the research areas in the context of the city of Tel Aviv (click to enlarge):

ResearchZones

The close up aerial photos below show clearly the differences in the street network between the traditional connected areas to the contemporary less connected areas:

The first area (marked with the number) is centered on Ibn Gabirol Street, which is one of the major commercial streets in the city. The second area comprises of Florentine Neighborhood. In these areas both the traditional and contemporary parts were planned, yet they differ significantly in the connectivity levels and in land use composition. In both cases the contemporary area is a super-grid of the older traditional area next to it. In addition, Florentine’s contemporary area was planned as an industrial area and as a result have a rather low residential density.

The third area comprises of the neighborhoods of Hatikvah (traditional) and Yad Eliyahu (contemporary), while the fourth area is made of the neighborhoods of Shapira (traditional) and Kiriyat Shalom (contemporary). In both of these case the traditional neighborhoods were unplanned in some sense and had a bottom-up process of generation. In contrast, both of their contemporary counterparts were planned from the top in the fashion of early modernistic planning after the second world war.

The following map shows our findings regarding observed pedestrian movement volume and retail fronts distribution in all of the research areas. The pedestrian movement volume is distributed in a heavy-tailed way, meaning that there are only a few streets that carry a lot of movement while most of the streets carry low movement volumes. To visualize this we have emphasized the points where the top 10% of pedestrian movement was observed with red points and the next 20% are highlighted using orange points. In this context, heavy pedestrian movement means over 400 pedestrian per hour and medium movement rate means stands for over 200 pedestrians per hour. As for retail distribution – streets sections in which both sides have retail are marked with red lines, while streets with only one side of retails are marked with orange lines.

PedestrianCountAndRetail

Basically, the traditional areas have a more connected street network, with a higher presence of retail fronts and a higher volume of pedestrian movement. Moreover, even in the traditional sub-area where the lowest pedestrian movement volume was observed (which is Shapira Neighborhood in the top of area number 4), the average movement volume per road segment was higher still than that in the contemporary sub-area with the highest pedestrian movement volume (which is the eastern Ibn Gabirol area – to the right of area number 1). Pedestrian movement is higher in that traditional area even though the residential and employment densities are lower than that of the contemporary sub-area.

It can be clearly seen that in all traditional urban area commercial streets have successfully developed, while in the contemporary urban areas no commercial streets managed to grow. This happened regardless of municipal regulations that sometimes tries to prohibit commercial development and at other times tries to promote it. The commercial streets have all developed along the most central streets. Over the fine grid of Florentine (top-right in area number 2) an extensive grid of commercials street had sprouted from the top-right intersection, which is a rather central intersection in the city of Tel Aviv.

In conclusion, urban commerce does not happen based on an abstract will of a planner, but is the result of certain conditions, where the most important aspect is the road network, its intensity and the centrality it provides to certain streets. The next post will deal with the statistical associations themselves between commerce, street centrality and pedestrian movement. In addition, these findings are in line with other studies on the growth of urban commercial activity. Recommended reading on this subject include the following papers, which are free to access:

“The effects of block size and form in North American and Australian city centres” by Arnis Siskna. This paper examines 12 CBDs of North-American and Australian cities and reaches findings on land use formation based on the street network and morphological structure. Siskna points to the spontaneous development of urban commerce in the shape of a spiky potato.

Another and better known paper extends Siskna’s findings: “Centrality as a process: accounting for attraction inequalities in deformed grids” by Bill Hillier. In this paper Hillier suggests several insights regarding the development of intense urban centers and the needed conditions for them.

And as previously mentioned, you can find my new paper which further confirms and extends on Hillier’s work here.

The Need to Combine Public Health and Urban Planning

16 Friday Oct 2015

Posted by in Academia, Planning

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A big report titled “Making the Case for Designing Active Cities” was published a few months ago by the Active Living Research Unit at the University of California in San Diego. This report synthesizes over 400 papers based on five physical planning subjects: Parks; Urban Design and Land Use; Transportation; Schools; and Buildings.

These five planning subjects and the papers relating to them are then evaluated to assess the co-benefits of activity-friendly design on six societal issues: Physical Health; Mental Health; Social Benefits; Safety; Environmental Sustainability; and Economics.

Not surprisingly, it appears that activity-friendly design has major benefits that are tied together – from health to economy and sustainability. Although there is a growing body of research linking urban planning to health outcomes the division between public health officials and urban planners remains strong, or as Neil Blackshow puts it:

Town or spatial planning as it is more accurately called has at its heart the attempt to manage those very same determinants of health – employment, housing, transport, education and environment. You might therefore expect it to be at the forefront of the challenge to improve health and wellbeing in our urbanising world, but this is not the case. There is strong evidence that there is a very poor level of mutual understanding and weak integration between planning and health professionals and their interventions.

Health officials in planning committees generally are busy with issues relating to industrial pollution and water treatment at best. Their spatial planning understanding is usually weak. In contrast, the urban planners tend to focus on the number of parking spots and housing units under consideration (sometimes the planning discussion only involves parking spots), and are oblivious to the general health and lifestyle outcomes their planning promotes or prevents.

This has been clearly said by James Sallis, Chad Spoon and their associates in the report mentioned above:

An important barrier to environmental changes that support physical activity is that decision-makers do not consider physical activity an important enough rationale to justify policy changes and investments. Even if a decision-maker is well aware of the important effects of physical activity on health and health care costs, health may not be on the agenda of the decision-maker. Decisions taken in the transportation, city planning, parks and recreation, education, architecture, and business fields often determine whether environments facilitate, or create barriers to, physical activity. Health is often not part of the mission of these groups. Though mayors, city councilors, and similar officials work everyday to balance competing interests, most of them do not understand that environments that support physical activity produce additional benefits for their communities. Thus, creating activity-friendly environments can be a solution that solves multiple problems.

This situations was evident at a recent three day workshop on planning for activity and public health at the University of Haifa. The participants were mainly from the health-related fields while the planners, geographers and traffic engineers were missing. This reflects the fact that planning related health issues are completely missing from the table.

Walking is discouraged along this road in Tel Aviv
Pedestrian and Vehicle Separation

The Active Living Research report concludes that the findings clearly support making decisions in favor of activity-friendly places, in face of current planning systems that work hard to design activity out of everyday life:

Changing policies about built environments is usually a politically difficult process, opposed by vested interests and vocal citizens. Evidence of the benefits of change may not be sufficient to overcome voices of negativity. Fortunately, we can expect many powerful voices to speak in favor of creating activity-friendly environments. Real estate developers can make more profits. Homeowners will likely see their properties appreciate. Retailers can expect more business. Most importantly, the majority of people, at least in the US, support more walkable communities, more walking and bicycling facilities, and more and better parks and recreation facilities. People want to live in walkable communities but cannot because zoning laws in the US favor single-use, automobile-dependent developments. Though there is opposition to every proposal, support for activity-friendly environments appears to be widespread and growing.

I hope that in the not too distant future, alongside the changes to the outdated traffic engineer profession, the new urban planners will also bear in mind the health outcomes of their designs and our public health officials will learn a bit on how urban planning affects their jobs.

Pedestrians welcome
Rotchild Boulevard

Modernist Planning Results in Fewer and Less Predictable Pedestrians

20 Thursday Aug 2015

Posted by in Academia, Israel, Land-Use, Planning, Transportation

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I am glad to share with you a paper that I have co-authored and which was published recently in the International Journal of Geographic Information Science. The paper was written by Prof. Itzhak Omer of Tel Aviv University, Dr. Yodan Rofè of Ben-Gurion University and myself. The full title of the paper is:

“The impact of planning on pedestrian movement: contrasting pedestrian movement models in pre-modern and modern neighborhoods in Israel”

As evident from the name of the paper, this publication deals with the impact of planning on pedestrian movement. We analysed pedestrian movement in 14 neighborhoods in four different cities in Israel – Kfar Saba, Bat Yam, Ashdod and Beer Sheva. These neighborhood where divided to two categories – modern and pre-modern. Essentially, modern neighborhood are those that were planned along modernistic urban planning approach, which adheres to separation of uses and hierarchical road structure. In contrast, pre-modern planning which tends to be denser with a lot more mix of uses and less hierarchical road structure. Basically, all the neighborhoods planned after the establishment of the state of Israel (1948) are modern, while most of the neighborhoods that were established prior to the Israeli state independence are pre-modern. Moreover, the cities of Bat Yam and Kfar Saba have many more pre-modern parts than the cities of Beer Sheva and Ashdod (this city was established in 1956 and consist only of modern planning).

Following are the maps of all the research neighborhoods in their respective cities. Dashed lines mark pre-modern neighborhoods while continuous lines mark modern neighborhoods.

All 14 research neighborhoods
NeighPicAll

We did pedestrian movement surveys in all the research neighborhoods and examined the statistical correlations of  the movement volume with relevant quantifiable variables that describe the built environment. For the analysis of the road structure we have relied heavily on space syntax. Other variables were derived from land use distribution – especially retail and demographic variables such as population densities.

Significant disparities in pedestrian movement volume were found among the cities and among the different neighborhoods. The pre-modern neighborhoods had about twice the pedestrian movement volume of the modern neighborhoods on average. Also, retail fronts were found to be much more prevalent in pre-modern neighborhoods than in modern neighborhoods. The chart below shows the average pedestrian movement volume (per hour) observed in the surveyed road section in all research neighborhoods. In red are the pre-modern neighborhoods, blue signifies the modern neighborhoods and green represents the average for each city. The city of Bat Yam, which is one of the denseset municipalities in Israel has remarkably higher movement volume than the other three cities.

Average pedestrian movement volume per hour in the surveyed road section in all research neighborhoods. Red is for pre-modern neighborhoods, blue for modern neighborhoods and green for entire city average.

Furthermore, our extensive statistical correlations showed that movement in pre-modern neighborhoods is far more predictable than in modern neighborhoods. At the last phase of this study we tried to produce a generic movement model for each type of neighborhood. To validate this model we analysed pedestrian movement in four more neighborhoods in Kfar Saba and in another city called Hod Hasharon (one neighborhood of each type in each city). The model had far more success in the pre-modern neighborhood than in the modern ones.

Besides addressing the issue of pedestrian movement in modern and pre-modern neighborhoods, the paper adds significant findings related to space syntax and the usability of its various attributes. For example, metrically derived attributes (based on metric distance and not on topological and angular distance) were found to be extremely inconsistent. The main conclusion I take from this work is quoted below:

Our study shows that traditional pre-modern urban neighborhoods, with a well-connected street structure, are likely to have not only more walking within them but also a more predictable spatial distribution of pedestrian volume than modern neighborhoods, that are characterized by hierarchical tree-like street layout associated with the idea of the neighborhood unit. We have identified that the correlation of pedestrian volume with the street network’s configuration attributes are significantly higher in pre-modern urban neighborhoods than in the modern neighborhoods. Furthermore, our study revealed that the distribution of pedestrian volume in these neighborhood types interacts differentially with the street network. In modern street layouts, the different types of configuration attributes (topological, angular, and metric) tend to be much more varied in their correlation with pedestrian volume across scale.

 

The full paper provides all the results and findings, expands on the use of space syntax in this research and describe in detail the statistical methods employed. You can find the full paper here, and if you cannot access the full paper and would like to read it you can contact me here and I’ll send you a copy.

The Neighborhood Unit – A Concept that Should Be Laid to Rest

25 Thursday Jun 2015

Posted by in Academia, Criticism, Planning, Transportation, Urbanism

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Criticism of modernistic urban planning and its failures tends to epitomize Le Corbusier as the main culprit behind the change in planning approach during the 20th century. Some may suggest that without Corbusier our urban planning would remain humanistic and rational like at has been during most of human history. While Corbusier definitely deserves an honorary place among the people who destroyed the profession of urban planning and created inhuman habitats, he was far from being alone, and was working in the zeitgeist of his time when many other planners envisaged a slew of anti-urban plans.

One of the modernistic concepts which is (unfortunately) still very much alive is the Neighborhood Unit. This concept was summarized by Clarence Perry in 1929 for New York Regional Survey and is the main subject of this post. Below is the most recognized diagram that is associated with Perry’s work. You may note that Perry surrounded his ideal neighborhood with highways and on further inspection you may also note that he avoided making any direct links from one neighborhood street to another neighborhood across the highway, thus making sure its neighborhood remains in its own limited world.

Neighborhood Unit Diagram. “New York Regional Survey, Vol 7” by Source. Licensed under Fair use via Wikipedia.
Neighborhood Unit Diagram

Perry advocated for planning of an autonomous unit centered around an elementary school with just a little bit of everyday needs in it. When reading his seminal text a few points pop up, that are unfortunately still very prevalent in current planning practices almost a hundred years later. For one, Perry’s meticulous analysis the elementary school (from page 46) carefully examines the number of children in an average household and goes on to use this demographic information as if it was written in stone. Well, as it happens average households in New York today are quite different than they were a hundred years ago (they are much smaller with much fewer families having three children or more) and will probably be very different in another hundred years. The same goes for his analysis of shopping needs (from page 76) which again assumes that society is static. Perry goes into enormous details on the specific shops that are needed inside a neighborhood unit (including a millinery, which is a fancy word for a hat making shop) versus those that should only be found downtown.

The basic assumption is that everything is static – demographics (family size) do not change and society needs at large do not change (schools, churches and so forth). Furthermore, as far as urban development goes, Perry assumes that in the future everything of importance will be concentrated in the downtown and no significant urban changes will occur in terms of metropolitan development and land use dispersal. To some degree, assumptions of an unchanging future are the backbone of all modernistic urban planning. After analyzing people’s needs Perry proceeds towards the street network he thought would liberate people. The text embraces full automobility as inevitable and predicts that in the future everyone will have an automobile and every trip outside of the neighborhood unit will be done by one. It assumes only two kinds of streets – local streets and fast highways. There is no place for main streets (major commercial streets) in Perry’s world. Against this unrealistic background Perry tried to address pedestrian needs and made his neighborhoods completely disconnected from each other and from the city that they were added to.

The diagram below shows how Perry viewed the classic American open-ended grid that is at the base of all the decent urbanism that still remains in the US. In his view the grid led to nowhere in particular, while his closed street scheme leads to “place where people want to go”. In practice the grid leads to a myriad of destinations open to change and growth, while a closed and disconnected street network leads to a place that’s quite resistible to change.

Where do you want to go today?
The neighborhood unit - Perry-42

The prevalence of the Neighborhood Unit concept in urban planning and current state of debate on its merits and downsides is neatly articulated in a recently published academic paper in the Journal of Urbanism by Michael Mehaffy, Sergio Porta and Ombretta Romice. The paper is titled: “The “neighborhood unit” on trial: a case study in the impacts of urban morphology”. Mehaffy et al. show that even advocates that work on urban planning reform such as the American New Urbanism tend to view the Neighborhood Unit in a positive way. The paper goes on to show how Perry tried to separate between slow pedestrians and fast moving vehicles so as to accomodate vehicular traffic to the largest degree possible. The authors dig deep and discuss how Neighborhood Unit plans may lead to increased segregation and significantly hamper public transit:

By not centering neighborhoods on arterials, the Perry model and its variants create a fragmented transit service area that cannot be serviced cost-effectively. According to such critics, this failure has a significant impact on the viability of a public transit system, and on the resulting ability to reduce carbon emissions from urban transportation.

In contrast to the dysfunctional Neighborhood Unit a few examples of real city development with emphasis on well connected urban fabric are given: London, Barcelona and my personal favorite – Portland, Oregon.

Perry’s Neighborhood Unit concept did not wreak havoc only in the USA, but spread across the globe. Israel, which was established during the modernistic golden age (1948) embraced the Neighborhood Unit concept with zeal and now has many municipalities made only of Neighborhood units with no real city parts whatsoever. One example for such a place is the port city of Ashdod (established 1956) which consists of a large port and industrial area to its north and 17 Neighborhood Units to the south. The city has about 250,000 people in it, but instead of utilizing this congregation of people it is actually made up of 17 villages of 10,000-20,000 people, each with its own slowly decaying low-level commerce. Below is Ashdod’s map with its disconnected neighborhoods.

Ashdod is now trying to take one of its arterial roads and turn it into a real urban street, connecting its disjointed neighborhoods (you can read more about it here) with an ambitious plan that tackles street network changes, land use changes, commercial development and public transit. Whether such a change is feasible is open to debate.

In conclusion, planners need to be aware of the Neighborhood Unit’s major shortcomings and should resist the urge to plan a closed and segregated ideal and never-changing urban habitats. After all, those places may be much worse than open-ended places that are open to change.

An Innovative Pedestrian Transportation Plan and Its Academic Publication

21 Sunday Dec 2014

Posted by in Academia, Israel, Planning, Transportation

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This post describes a planning project I’ve been involved with, in which we created an innovative pedestrian transportation plan for the city of Bat Yam in Israel. Bat Yam is an inner suburb in the Tel Aviv Metropolitan area where about 130,000 people live just south of the municipality of Tel Aviv. Besides the novel transportation plan, we have managed to publish an academic paper, adding to the global discussion on city and transporation planning. The paper was published in Geographic Analysis (together with Dr. Yodan Rofè and Prof. Itzhak Omer) in a special issue dedicated to Street Networks and Spatial Analysis, following a workshop in Dresden last year. A non-final version of the paper can be found here (or you can contact me for the final version). And now to the actual story itself.

Transportation planning is changing. What used to be a concern with motorized vehicles only is evolving into a discipline dealing with multi-modal systems where priority is given to transit and non-motorized means of transport, chief among them being walking. Walking is important for several reasons: reducing reliance on motorized travel, which is rather costly, polluting and accident-prone; walking as part of a daily routine, promotes healthier life-style; and walkability can improve the economy of urban centers. Across the globe, effort are made to improve conditions for pedestrians. Known examples include New York City, Copenhagen and many more. Following this trend, The Israeli government has also published guidelines for streets design (here – in Hebrew). However, pedestrians in Israel are still at the bottom of the transportation and urban planning considerations.

The city of Bat Yam in Israel has chosen to pioneer planning for pedestrians as an integral component of its transportation master plan. The transporation master plan for the city of Bat Yam includes all transportation means (i.e. private vehicles, parking, bicycles and so forth) and was led by PGL Transportation and Engineering Ltd. We were in charge of pedestrian transportation in the overall scheme and we hope that more cities and other public bodies will consider walking as an integral part of urban transportation.

This project touches on one of the growing issues in urban planinng which is evidence-based design. This approach originated in the health and medical fields, and is now entering the realm of city planning. We managed to combine research and praxis and made a contibution towards a change in the area of urban planning. A few different subjects were joined together in this project – Space Syntax, pedestrian movement, general urban transportation and city developement.

Besides analysing pedestrians movement, we had to address expected changes to the urban strcuture of Bat Yam in target year of the plan (2030). The major changes are expected to happen in the southern industrial zone of the city in addition to a new residential neighborhood on open land at the south-western edge of the city. These changes include modifications to the street network as well as land-use changes and plenty of new construction. The southern industrial zone is supposed to grow from current under-utilization to intensely built zone including lots of retail, office and residential high-rise buildings.

We have constructed pedestrian movement models both for the current state of the city of Bat Yam, and for its future state in 2030. The future model included the changes expected to the street network and land-use. The model was constructed based on space syntax methodology and correlated based on pedestrian traffic counts in 69 street segments all over the city. The map of the traffic survey is shown below. I will not go into the entire method (which is explained in detail in the paper) – the large red points represent average movement volume of over 900 pedestrians per hour, the medium points represent average movement volume of over 430 pedestrians per hour, and the small points represent lower volumes.

Three areas in the map have groupings of high movement points. These three areas have some kind of combination of high centrality with high presence of retail. The northern points are in the old center of the city (Memorial Square), the points further south are at the junction of the main commercial street (Balfour Street) and a major east-west street, and the points at the eastern edge are next to the (new) main entrance to the city and its largest shopping mall. Contrary to the municipality’s expectations, pedestrian movement along the beach front (on the western edge of the city) is relatively sparse. Most of the everyday pedestrian movement on a weekday probably is related to functional activity and not to leisure. This movement takes place mainly on the streets that define the epicenter of the city.

Pedestrian movement survey for the city of Bat Yam

PedSurveyHeadTailForPaper

In the movement model itself we managed to achieve a correlation rate of 62% using three variables (not bad compared to similar studies), where the major variable is based on street centrality and the second variable is associated with retail front presence. Thus, we have reached two main conclusions that enable this method to be used in other cities:

1. Pedestrian movement distribution can be explained mainly by spatial structure of the street network. Changes to this network structure are relatively rare, and therefore pedestrian movement distribution will be similar in the year 2030, and the main streets for pedestrian movement will not change in a fundamental way.

2. Because the model is not accurate it should be used with caution. Therefore, we have taken 20% of the streets where pedestrian movement volume is highest and they were declared as the pedestrian core network. This layer was then overlayed on other transportation layers – public transit, private vehicles and bicycles.  This is the place where our model can have impact on the real world and on the future work of the municipality – by directing the focus to streets and places where conflicts among the various road users (pedestrians, bicycles, transit vehicles, and private cars) are expected. This conflict analysis can be used to develop a policy that favors pedestrians as well as to highlight areas where safety improvements are needed. The model also can enable an urban development policy that seeks to improve public space where the highest pedestrian movement rates are expected.

A map of the Superimposed future pedestrian core network, public transit (including planned light rail), bicycle routes (planned), and major vehicular roads.  supermap bat-yam-NEW

As the map shows, there are few important streets, but these few streets carry a large share of the different kinds of transporation means and they are the places where conflicts among road users are expected. These streets deserve most of the planning efforts and investing in them has a large impact on the city and its residents.

The entire paper can be downloaded from here.

Israeli Planning is Homogeneous and Wasteful

30 Thursday Oct 2014

Posted by in Academia, Criticism, Housing, Israel, Planning, Urbanism

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This post is based on an academic paper by Daniel Orenstein and Steven Hamburg. The paper sheds light on the Israeli planning system which seems to be producing homogeneous and wasteful products. The full name of the paper is: “Population and pavement: population growth and land development in Israel” and it was published in Population and Environement journal.

The reserach examines the connection between the population growth in Israel and the urban development in the years 1961-1995 (based on four population censuses in the years 1961, 1972, 1983 and 1995). The authors looked at the national level, district level (the six districts that make up Israel) and local level (by examining 40 local authorities). The paper focuses on the conversion of open land to built-up land across time. This land conversion process is compared with population growth has and the way regulation impacts on this process. This reserach was carried out against the background of the necessity to avoid obliterating the remaining open land in Israel. The researchers raise three questions:

1. What is the connection between population growth in Israel and the rate of converting open land to built-up land?

2. Does the scale of analysis affect the strength and magitude of this correlation (scale means national, district or local)?

3. What are the regulatory means that infulence the rate of open land conversion and in what ways?

To carry out the research a number of specific areas all across where chosen including urban, suburban and rural settlements which are also ethnically diverse (meaning taking into account also predominately Arab settlements and not only predominately Jewish settlements). Out of 250 local authorities in Israel 40 were examined (for more please see pager 9-10 in the paper itself). After the selection of the research areas the paper elaborates on the methods used, which employed analysis of aerial photos from different years in order to assess the amoung of land that was converted from open to built. To make the story short I’ll focus on the major findings that arise from this paper.

The first important finding in the national level is that the rate of open land conversion to built-up land is higher than the rate in which the population is growing. Furthermore, this conversion rate is even higher if the sparsely populated Galilee and Negev regions are taken out of the equation. Namely, the open land we build on for the additional population is being eroded at a rate that is growing over time. We waste our land faster than we used to. Another somewhat intuitive finding shows that the rate of sprawl (open land conversion for each additional resident) is higher for the rural settlements and for the northern settlements.

In contrast to the national level, when looking at the sprawl rate at the local authority level, we see that the planning gets more and more homogeneous. The rural regions have a lower sprwal rate than in the past, while the urban areas have a rising rate of sprawl approaching the rural rate. The Arab settlements (which had a tendency for higher sprawl rate) have a decreasing rate of sprawl, while the Jewish settlements have a rising rate of sprawl approching the Arab rate. Thus, while at the national and district levels we are eroding open land at a rising rate (also by establishing new settlements), at the local planning level the urban planning becomes more and more homogeneous. In the words of the researchers:

Sprawl (more space consumed per additional unit of population) is increasing over time at both the national and district scale, yet the locality data do not corroborate these results. The locality data suggest a growing homogenization of development across the Israeli landscape.

Particular attention was given to the effects of the Jewish population dispersal doctrine on the rate of open land conversion (this doctrine goes back to 1948 and aims to redistribute of the Jews in Israel while idealizing rural agrarian lifestyle). It was found that this doctrine is responsible for more open land erosion than the rest of the faulty Israel planning regime. And here is the text itself:

The amount of land developed in the peripheral areas was significantly higher than in the core area, once variation due to population growth and other related factors are removed. Likewise, development in Arab localities was less than in Jewish localities (controlling for other factors), although this difference was statistically significant only for the full 1961–1995 study period. These results reflect a consistent Israeli policy to encourage internal migration of Jewish citizens to the peripheral areas, while concurrently restraining the growth of Arab localities (Falah 1991; Khamaisi 1993; Yiftachel and Rumley 1991), despite the preference of most Jews to live in high-density urban communities in the geographic core area of the country (Kellerman 1993). Various national policies have attempted to attract Jews to the peripheral areas (Kellerman 1993; Newman 1984, 1989). Among them was the development of small, exurban communities with larger homes. By attracting people to these communities, policy magnifies the impact of local population growth on open space in Jewish, rural localities where the amount of land developed per capita is an order of magnitude higher than in any other type of development.

The most astonishing find is the failure to stop open land erosion even in districts where there is not much open land left. Namely, even in places where there is not much open land left, the sprawl rate is not declining. Here it is (emphasis mine):

One somewhat surprising result of the population–development relationship is that for districts in which open land is becoming increasingly scarce, an expected slowing of land development relative to population growth with a concomitant increased importance of open space was not evident. We would have expected to see the rate of land development slow as open space became increasingly rare. Rather, we see the rate of loss of open-space increase (and the rate of land development increase) as open land reserves become smaller. This is true even in the case of the Tel Aviv district, where only a small amount of land (*20%) remained open space by 1990.

In conclusion – at the local level our planning is becoming more and more uniform and provides indication about a central technocratic systems that operate with no context, and creates a uniform built environment. At the district level we are unable to save the open land at all. And at the national level, the loss of open land is at a higher rate than the rate of population growth. For the good of this small and precious country, its planning systems need to be completely reorganized and most of the regulation and the ideology standing behind them have to be shredded – the sooner the better.

You can access the full paper here (and if you do not have access and still want to read it you can leave a reply or contact me).

Do Comprehensive Land-Use Plans Have any Real Meaning?

14 Tuesday Oct 2014

Posted by in Academia, Criticism, Israel, Land-Use, Planning, Urbanism

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The Israeli planning system deserves a few posts on its problems and challenges. Today, we’ll deal with a study that attempts to evaluate the effectiveness of district master plans with regards to the actual implementation. This post is based on an academic paper written by Dr. Nurit Alfasi, Mr. Jonathan Almagor and Prof. Itzhak Benenson, and which can be found here. This paper was published in Land Use Policy Journal under the title: “The actual impact of comprehensive land-use plans: Insights from high resolution observations.” The researchers have made an attempt to estimate how much does actual construction conform to the actual plans by comparing aerial photographs to district master plans. The results of this study shed light on the ineffectiveness of the urban planning in Israel and should signal to the Minstry of Internal Affairs (that is responsible for most of the actual planning) that it is time to change the way in which the system operates.

First, we must clarify what is meant by district master plans. Israel is divided into six different administrative districts. This division was first created during the British Mandate period and was slightly changed after the establishment of the state of Israel, but is no longer relevant. For example, the Tel Aviv District includes the contiguous urban area that was already built in 1948 (Tel Aviv and its inner suburbs from Hertzliya in the north to Bat Yam in the south). The Central District includes what used to be the agricultural hinterland of Tel Aviv and is now part of the suburban sprawl from Natanya to Rishon Letziyon. Even the Southern District includes part of Tel Aviv Metropolitan area, especially the large suburb of Ashdod. So, after understanding this anachronistic districts division we need to deal with the actual district master plan. This is a comprehensive plan that describes the entire land-use specifications (built and planned) for the whole district. Each district has such a plan and this plan is supposed to set the expected development in the district and has to be updated once all of its planned development have been built. In theory, most of the construction should follow the district master plan, and the discussions in the district planning comittee should ensure that all roads, buildings and parks are built according to the approved plan.

The study dealt with the Central District for its area of reserach. This is the district with the most intense real estate activity in Israel and includes all the growing suburbs of Tel Aviv outside of the inner ring. The study focused on the district master plan also knows as DOP 3 (District Ouline Plan no. 3), which was approved back in 1982. In order to compare the actual construction to the plan aerial photographs from the years 1980, 1990, 2000 and 2006 were used – all in all 26 years of development. DOP 3 itself has undergone an update process in 2002 and became DOP 3/21. Twelve different areas inside the Central Districty were sampled, constituting about ten percent of the entire district area.

Several key findings are revealed when examining the plan compared to the actual development. During the years 1980-1990 more that 50% of the areas developed did not conform to the plan land use map. Yep, you got it – 50 perecnt of the development did not conform to the plan. During the years 1990-2000 the plan was getting even further from reality and more than 60 percent of the areas developed did not conform to the district master plan. It can be concluded that only a small part of land development actually occurs in accordance with the plan itself. It should be added that almost all of the non-conforming land developement was approved by the planning committees themselves, meaning that the planners themselves completely ignore the plan that they have approved to much fanfare. We need to remember that the district master plan is a public plan that costs a lot of time and effort. Additionally, this plan is used for countless comittee discussions wasting even more time. In light of the plan irrelavance it would actually be better to work without such a plan that only wastes resources and does not contribute to the actual planning and developement. The reserchers have also checked whether there was so much developement that the plan allotted areas for development were just insufficient. In a thorough examination it appears not to be the case. There remained enough approved land for development that was not devloped, while the actual construction took place on land that was not slated for development. In the words of the authors themselves:

It appears that despite the vast effort and time invested in preparing and authorizing district land-use maps, this is not an efficient planning tool in terms of restricting development in specific locations

Of all the anecdotes that come out from this study, the most ridiculous case is illustrated in the case of a newly established suburb in the 1980s titled Shoham. Shoham was founded entirely on and area defined as a future public park,  meant to be kept open for its unique environmental values (in sharp contrast to the area defined as farmland, which are easy to run over with urban development.) DOP 3 was approved in 1982 and just a few years down the line, the National Planning Council made the decision to build Shoham. But the problems do not relate just to the 1980s and 1990s. In 2002, a new DOP 3 was approved under the name DOP 3/21 which paractically approved almost all the deviations that occured in the preceding years. Over the four years that were checked after the new DOP was approved, non-conforming development has already started to be prevalent and reached 30 percent in a number of the sampled areas.

At the conclusion of the study, the reserachers elaborate on effective planning methods to replace the current system. These methods do not include rigid and meaningless land-use maps, but a defined set of planning principles by which to evaluate local plans before their approval and execution. Such an action can guarantee a faster and more flexible design that also gives better results. I hope that theserecommedations will not remain only on paper.

The complete paper can be found here.

Where Is the Science of Cities Heading?

04 Saturday Oct 2014

Posted by in Academia, Urbanism

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The science of cities is in a somewhat similar state to what medical science was 500 year ago. The 20th century was filled with attempts to “engineer” the city and tread is with bloodletting. Modernist planning created crippled cities. If the modernist planner were to create a human being it would have been formed in its mature form, and growth pains have been avoided. On the other hand this human being would not have an identity and its capacity to learn and evolve was rather limited. A guest editorial in Environment Journal says it clearly: “It’s time for and Urbanization Science”. This editorial offers a number of reserach fields, which deal with the relationship between the real world and urban science and which will expand in the coming years:

We need a science of urbanization. This science would focus on the fundamental laws of the urbanization process: its origins, development, organization, emergent properties, and connections to other social and biophysical processes.

One of the tremendous efforts in the science of cities recently is Shlomo Angel’s book – Planet of Cities. Angel points out to the fact that during this century the world’s urbanization process will be completed (i.e. the transition from rural to urban will reach saturation) and that there are still many opprtunities for improvements and corrections. Angel’s findings realted to cities and urbanization are based on reserach spanning 3,646 cities of 100,000 or more inhabitants all across the globe. Angel offers a paradigm he calls “Making Room”, meaning preparing a place for urbanization in places were the urban popoluation is set to rise rapidly (mainly in the developing world), and gives examples for past successes  such as New York’s 1811 Commissioners’ Plan and Barcelona’s 1859 Eixample Plan.  A good summary of this fine book can be found here.

PlanetofCitiesMedium

In the world of urbanization science we have serious holes in the pseudoscience known as city planning. An easy article helps to clarify this a bit: “Urban Legend: Can City Planning Shed Its Pseudoscientific Stigma?” It raises the question whether urban planning can be truly scientific instead of relying on emotions, unclear texts and plain BS like it is today. This short article is based on an excellent academic paper by Stephen Marshall that is called: “Science, pseudo-science and urban design”. Marshall demostrated that there is hardly any use of academic methods in urban planning and that in fact there is no scientific theory of urban planning. Marshall shows that we did not learn almost anything since Jane Jacobs wrote:

As in the pseudoscience of bloodletting, just so in the pseudoscience of city rebuilding and planning, years of learning and a plethora of subtle and complicated dogma have arisen on a foundation of nonsense.

The most important table in this paper shows that urbanistic theories by Jane Jacobs, Christopher Alexander and Kevin Lynch, all of whom are great urban thinkers, have not been scientifically tested. In the few cases these theories did go under scientific tests, they did not stand them. It appears that the four principles of Jane Jacobs (mix of uses, short blocks, buildings of different ages and density) have not proven to contribute to urban vitiality. Marshall suggests that urban planning should be established as a real science.

To conclude, the science of cities and the part of scientific urban planning need a lot more reserach and this reserach might as well happen while the world is still undergoing major urbanization processes.

Summary of links for further reading:

It’s Time for an Urbanization Science

Urban Legend: Can City Planning Shed Its Pseudoscientific Stigma?

Science, pseudo-science and urban design

Planet of Cities