Friday, August 28, 2009

Resiliant Cities

Resilient Cities: Responding to Peak oil and Climate Change by Peter Newman, Timothy Beatley and Heather Boyer is an important book for anyone interested in transitioning from unsustainable, car based, suburbs to a lower energy, transit based system.

The authors identify seven key elements of a resilient city.

1. Urban areas will be powered by renewable energy technologies from the region to the building level.
2. Every home, neighborhood, and business will be carbon neutral.
3. Cities will shift from large centralized power, water, and waste systems to small-scale and neighborhood-based systems.
4. The potential to harness renewable energy and provide food and fiber locally will become part of urban green infrastructure.
5. Cities and regions will move from linear to circular of closed-loop systems, where substantial amounts of their energy and material need are provided from waste streams.
6. Cities and regions understand renewable energy more generally as a way to build the local economy and nurture a unique special sense of place.
7. Cities, neighborhoods, and regions will be designed to use energy sparingly by offering walkable, transit-oriented options for all supplemented by electric vehicles.

New Urbanism

New Urbanism has become quite popular among city planners, especially in “environmentally conscious” areas such as Montgomery County. The New Urbanists have promoted high density “walkable” communities as an effort to reduce reliance on automobiles. High density neighborhoods are springing up around every metro stop, and even where there is no easily accessibly metro stop.

But Resilient Cities has a warning for the New Urbanists. A study of New Urbanist developments in Perth, Australia, demonstrated some of the weaknesses of a New Urbanist approach. The study compared eleven New Urbanist developments with forty-six conventional suburbs. The New Urbanist developments had a 9 percent switch from cars to walking for local trips, which also came with a 7 percent reduction in obesity.

However the New Urbanist developments showed no difference in total fuel usage for transportation. Fewer car trips for local travel were balanced out by greater use of cars for longer trips and reduced car occupancy.

The quality of transit available was a significant factor. A typical transit trip to work would have taken over 80 minutes compared with 30 minutes for a car trip. None of the New Urbanist suburbs produced the density and mix of uses in their centers to be self sufficient, leaving them reliant on quality transit services to make any difference.

An analysis of transport fuel use across Australian cities has shown several strong relationships between transit quality and fuel use. The closer the development to the city center, the higher the density, and the higher quality of the transit service, the lower the fuel consumption. Quality transit service was defined as whether an area had a better than 15 minute service.


All of the available data shows that building more highways creates more traffic while tearing up highways and creating pedestrian and bicycle friendly cities decreases traffic.

Surveys show that the higher the average speed on freeways, the more fuel per capita is used. Cities with higher congestion have lower fuel use while cities with the least congestion use the most fuel. Increasing road capacity will cause car use to increase to fill the newly available space. A study by the Texas transportation Institute of US cities over the past thirty years shows no difference in the levels of congestion between those cities that invested heavily in roads and those that did not.

There is a growing awareness among some traffic engineers of this problem. Andy Wiley-Schwartz, from Project for Public Spaces says, “Road engineers are realizing that they in the community development business and not just in the facilities development business.” This new viewpoint has crystallized in the “slow road movement.”

Some cities are ahead of the curve on this development. For the past thirty years, Copenhagen has removed two percent per year of its parking space from the streets and squares and created pedestrian areas. Each year car use has declined while cycling and pedestrian use has increased.

In the US, the Complete Streets movement is attempting to create a similar shift, creating new public spaces in every community. The Project for Public Spaces has also sponsored many similar projects.

Examining what shape cities take in the future is vitally important to our ability to adapt to a lower energy economy.

Sunday, August 16, 2009

Water Wars in the US Southeast

The semi arid US Southwest has been accustomed to bitter conflicts over water rights, but now years of drought combined with rapid growth have sparked a fight between Georgia, Alabama and Florida over the rights to the use of water from the federal reservoir at Lake Sidney Lanier.

In July, a federal judge ruled that the U.S. Army Corps of Engineers erred by putting drinking water for Atlanta before Lake Lanier's mandated purposes: hydroelectric power, navigation and flood control.

The judge gave Congress until 2012 to work out a water-sharing deal among Georgia, Alabama and Florida or most of metro Atlanta will have to scale back water withdrawals to 1970s levels.

Although the severe drought conditions that plagued the Southeast in recent years have lifted, Atlanta's rapid growth continues to strain the demand for water. Atlanta grew by roughly 890,000 between 2000 to 2006, according to the U.S. Census Bureau, the fastest growth of any metro area in the U.S.

Some in Atlanta believe that the court case was a result of envy of Atlanta's growth. Charles Krautler, the director of the Atlanta Regional Commission, complained that, “The only motivation is political. We don’t have as good of spin doctors as they do. It’s easy to point the finger at big bad Atlanta.”

But Alabama Governor, Bob Riley replied that, “Atlanta has based its growth on the idea that it could take whatever water it wanted, whenever it wanted it, and that the downstream states would simply have to make do with less.”

Congress must now approve Atlanta's use of the Lake Lanier water for drinking water in the next three years, which may be a difficult task given that the Florida and Alabama delegations to Congress outnumber Georgia's

Water wars may continue to spread to other parts of the country. In his 2006 book, The Great Lakes Water Wars, Peter Annin looks at the past and present conflicts over the largest collection of fresh surface water on earth which may also become a battlefield for water for parts of the country straining the limits of their local supplies.