Tag Archives: street design

more trees!

This article in Landscape and Urban Planning is all about street trees. You would think this topic would have been exhausted, that is the technology would have been perfected, by now. And it has, in a few places. I am convinced it is not that leading edge knowledge about trees needs to be advanced all that much, but most cities are completely ignorant of what the best practices are. People in charge don’t know what they don’t know and have zero interest in finding out.

Street trees are an integral element of urban life. They provide a vast range of benefits in residential and commercial precincts, and they support healthy communities by providing environmental, economic and social benefits. However, increasing areas of impermeable surface can increase the stresses placed upon urban ecosystems and urban forests. These stresses often lead tree roots to proliferate in sites that provide more-favourable conditions for growth, but where they cause infrastructure damage and pavement uplift. This damage is costly and a variety of preventative measures has been tested to sustain tree health and reduce pavement damage. This review explores a wide range of literature spanning 30 years that demonstrates the benefits provided by street trees, the perceptions of street trees conveyed by urban residents, the costs of pavement damage by tree roots, and some tried and tested measures for preventing pavement damage and improving tree growth.

walkability matters – duh

For people still looking for an answer to the question “does walkability matter?”, here is some more solid evidence from Cities to add to the mountain.

In this study, researchers examined 170 neighborhoods in a medium-sized city to see whether walkability influences neighborhood sustainability. Until 2008, there had not been a reliable measure of the social, health, and economic impact of walkable neighborhoods. This dramatically changed when scholars were able to quantify walkability with tools such as Walkscore™; which measures how accessible daily living activities are by foot. The researchers investigated how walkability impacts the quality and sustainability of a neighborhood. They developed models that evaluated the correlation between an area’s Walkscore™ and four broad measures of urban sustainability: neighborhood housing valuation; foreclosures; and crime. Our analysis shows a positive impact not only on neighborhood housing valuation but also on neighborhood crime and foreclosure. These results provide policy opportunities for planners and citizen groups to pursue strategies to encourage the development of more walkable and sustainable neighborhoods.

I know I’m a broken record, but getting around under our own muscle power for most trips most of the time is the key to (in no particular order):

  • reducing carbon emissions
  • reducing air pollution from vehicle emissions, especially particulates which cause asthma and heart disease – this will add quality years to all our lives
  • solving drunk driving
  • saving lots and lots of money that we used to spend on cars
  • saving enormous amounts of space in cities that used to be used for car maneuvering and parking – space that can now be used for relaxing, recreating, habitat, housing, economic or commercial activity
  • creating space for people – yes, you can increase density and reduce crowding at the same time
  • increasing physical health through more physical activity, decreasing obesity, diabetes and heart disease, adding years to peoples’ lives
  • improving psychological health through physical activity
  • increasing social interaction
  • increasing business activity and profits
  • creating an ecosystem of innovative, creative people, businesses, nonprofit and government agencies

protected bike lanes

Continuing on my recent transportation theme, this article on Alternet has some really good statistics on protected bike lanes. I am convinced that biking (a.k.a. cycling) is just a more practical way to get around urban areas than cars – it gets more people from point A to point B with less infrastructure, less cost, less wasted space, and no pollution. Plus, it promotes a more healthful, active lifestyle and urban design that supports that.

But for all this to happen, we have to build cycling infrastructure that is truly safe, and the U.S. just hasn’t fully committed to that. There are signs of hope, however – here are some of the statistics I’m talking about:

  • 27% of all trips in the Netherlands are made on bicycles. The Dutch designs are not secret but are available here (although their manual costs 90 Euros and it is not clear to me whether an English version is available).
  • The “pioneering” American city in protected bike lanes is…Montreal with over 30 miles (I just remembered, Canada shares our North American continent). But New York City has caught up and surpassed them with 43 miles. Other cities are Chicago (23 miles), San Francisco (12 miles), Austin (9 miles), and D.C. (7 miles). (Here in my native Philadelphia, we have not built protected bike lanes but have closed some lanes to traffic and painted some new stripes on the streets that would allow us to eventually separate them. Philadelphia has a burgeoning cycling culture and I think eventually it will happen. We don’t like to do anything first, we always sit back and watch what New York is doing for a few years before we build up the courage to try something new.)
  • Studies are finding that bike infrastructure boosts retail sales – 49% for a street in New York, 24% in Portland – and 65% of merchants surveyed reporting positive effects in San Francisco. (I’m not surprised by this – there is less space wasted on car travel lanes and parking, less time wasted circling around looking for parking, less money spent on parking, more room for trees and fountains and sidewalk cafes – you have more people in a given space, yet less crowding, with more time and money on their hands and a nicer environment where they want to hang around.)
  • And…duh…protected bike lanes are safer for everyone, and add more capacity to move more people at much lower cost compared to new traffic lanes.

The article also links to this fantastic collection of articles and data on protected bike lanes from “peopleforbikes“.