@Strib: Building Productive Places in the Air


Note: An abridged version of the following post was also published online at the Star Tribune's Your Voices forum. Your comments are welcome in each forum.

The realities of climate change, rising gas prices and budget constraints compel us to use our developed area more intentionally and productively. Our assets will need to produce multiple benefits – parking lots become stormwater collection systems, roofs become collectors of energy, and road rights of way become tillable land area. All around us is space that we’ve underused over time.

Bridges are a good example. Inhabited bridges, or bridges that support a superstructure of residential and commercial buildings, are being reconsidered as an innovative way to add capacity, jobs, tax base, green space and character to urban centers. As in many cities located on major waterways, bridges can serve as iconic landmarks that structure the urban landscape and hold powerful symbolic connotations of community integration. And beyond symbolism, inhabited bridges capture space from the air, to house jobs or shared spaces. 

Vecchio_by_CGoulao Certainly not a 21st century innovation, bridges that contain residential and commercial uses have been an historic solution to limited available land for development in medieval European cities. From the 12th to the 18th centuries, at the apex of their popularity, mixed-use bridges were built throughout Europe. In economic terms, their construction shows that the value of proximity outweighed building and maintenance cost. Notable and popular examples include Old London Bridge, Ponte Vecchio, and Ponte di Rialto (here are the shops). The Old London Bridge was built in 1209 and housed nearly 200 shops as well as numerous residences that provided the revenue for the bridge’s construction and maintenance. 

Still standing in Italy, the Ponte Vecchio of Florence and the Ponte di Rialto of Venice (built respectively in 1345 and 1591) continue to be iconic structures and popular tourist attractions lined with flourishing shops. With little land available for expansion, medieval cities built inhabited bridges to maximize available space while minimizing government expenditure on maintenance through the taxation of residential and commercial entities inhabiting the bridge. The popularity of inhabited bridges, however, all but vanished following the 18th century as the demands of traffic and outward movement escalated, and the value of proximity fell in relation to construction and maintenance costs. 

Nonetheless, the inhabited bridge may not be a mere relic of the past but innovative solution to modern urban problems. The surviving Italian inhabited bridges testify to their modern applicability and the lasting import of their unique construction.  

Following their heyday, numerous plans for inhabited bridges have both been proposed and denied due to their perceived impracticality in a world dependent on motor vehicles. However, at the turn of the 21st century, the idea of inhabited bridges has gained greater attention. Construction of inhabited bridges appears to offer significant benefits and opportunities for the modern city. The “Living Bridges: The Inhabited Bridge: Past, Present & Future” exhibit at the Royal Academy of Arts in London in 1996 brought the concept of inhabited bridges to global attention and was met both with enthusiasm skepticism. A large component of the exhibit was an architectural competition to design an inhabited bridge. 

Again, in 2009, a similar competition was undertaken to commemorate the 800th anniversary of the construction of the Old London Bridge. While much of this interest has not begotten bridge construction, the inhabited Zaragoza Bridge crossing the Ebro River in Spain was constructed in 2008 to combine a pedestrian walkway with exhibition spaces focusing on water sustainability. Although new construction, the Zaragoza Bridge is an initial effort at redeploying the inhabited bridge for modern development. 

As global and economic factors converge to redirect our attention inwards, we are faced with cities that are compartmentalized by networks of major roadways. Communities and businesses within our cities are separated by natural barriers like rivers as well as man-made ones. Symbolically and physically, these communities are in need of being bridged. The inhabited bridge may serve to restore a disjointed urban social fabric, and release space for the creation of jobs, tax base, green space or others uses in places across the country.

Photo: Ponte Vecchio detail. Courtesy of Flickr/CGoulao

@Strib: Foreclosure Continues Regional Damage


Minnesota’s housing market is stabilizing, but prices dropped more here than the national average. Mortgage delinquency is at or over the national average in Isanti, Sherburne, and Chisago counties. These three, as well as Anoka and Scott counties, are among the state’s ten counties currently hardest hit by foreclosure, according to the New York Federal Reserve Bank.

A new study suggests this is consistent with a national trend. Households located in areas far from jobs and services are more reliant on long car commutes and their expense, creating another hurdle for households as job losses have accumulated. These maps illustrate who pays the largest share of household income to transportation and housing costs – exurban residents.

Foreclosure and vacancy is toxic for any community, urban or elsewhere. It’s not particularly constructive to introduce “slumburbia” as a new label for hard-hit exurbs and suburbs. If access to parts of our region is contingent on cheap, subsidized gas prices, people who buy property are exposing themselves to changes in those prices. If many homeowners in one area do so, the effects can be brutal for neighborhoods.

The Twin Cities region has grown by up to 25 acres per day in recent years. Providing houses with water and sewer, roads and other infrastructure demands a long-term and expensive public commitment. The foreclosure wave serves to highlight how households, local and state governments are all leveraged by development that relies on cheap, distant commutes to workplaces and services. As we’ve relearned in recent years, leverage works just as swiftly in reverse as it does moving forward.

Note: This piece is also published on the Star Tribune website in its Your Voices forum. See Commers posts on Your Voices here

@Strib: Reconnecting Minneapolis’ Seven Corners and West Bank


Like many urban and rural places, Minneapolis and St. Paul each have plenty of underutilized land area.

One of Minneapolis’ most striking examples is the Washington Avenue “trench,” a 1960s-era highway that today splits the Seven Corners area, the University of Minnesota’s West Bank, and the Cedar-Riverside neighborhood. Current plans call for construction of light rail transit service through the middle of the trench, a station beneath the 19th Avenue bridge, and a pedestrian/transit mall on Washington Avenue just across the river. In tandem, these plans translate to an opportunity for fundamental rethinking of how the trench inhibits the health of the places around it.

I have posted a piece about these issues at the Star Tribune (link to that post), and I have included here at the Cents of Place, additional images created by University of Minnesota graduate students of architecture working with adjunct professor Mic Johnson, also of Ellerbe Becket. My thanks to Mic for his permission to include these images.

The view east along Washington Avenue, with the LRT station area in foreground.

The view westward along Washington Avenue.

A bird's eye view of the redevelopment scenario for Washington Avenue right of way.

@Strib: Twin Cities Gearing Up for Greenways

Minneapolis Concept Routes

In mid-July last summer, gas prices peaked, remaining in the range above $3.50 per gallon until late September, 2008. One consequence of the spike was a boom in interest in commuter bicycling. July traffic on the Midtown Greenway, the principal bike commuter infrastructure in the Twin Cities, was 30% higher in 2008 than the previous year. An average of over 4,100 cyclists per day used the Greenway at Hennepin Avenue.

Greenway traffic diminished slightly this summer, thanks largely to a 40% drop in the price of gasoline. But interest in establishing a network of greenways has continued to rise. Two new efforts – the Twin Cities Greenways Initiative and the St. Paul Greenway Committee – suggest that the many interests who stand to benefit from an effective bike commuter system are joining together to move it forward.

The Twin Cities Greenways Initiative, inspired by the combination of ridership and development in Midtown, is working with neighbors to explore conversion of residential streets to greenways, linked together eventually in a network to link neighborhoods, schools, open space and commercial areas. “As we talk to neighbors,” said advocate Matthew Hendricks, “we find that 90% of them respond very positively to the idea of converting their streets to greenways.” Auto access would remain to homes via the alleys, as illustrated above.

Greenway Base Model 1B

The St. Paul Greenway Committee is stimulating interest east of the river in a facility akin to the Midtown Greenway – to which many in St. Paul have long sought a connection. Led by transit advocates St. Paul Smart Trips, the committee intends to begin planning with neighborhoods, to determine which connections will link high-priority destinations most effectively.

Greenways play a key role in a transportation system where implemented. They also enhance property values – a case proven by numerous studies of comparable cities. Gas prices will rise from current levels in the future, and providing affordable choices for getting around is key to our region’s competitiveness and quality of life.

Greenway Base Model 1D

Note: This post is also available at the Star Tribune, with fewer images. 

All images courtesy of Michael Nelson and Twin Cities Greenways Initiative.

Transportation Stimulus Projects Should Reflect Modern Economy

A New York Times analysis of over 5,000 transportation-related stimulus projects released todayFour-lane rural road near Fort Ripley, MN indicates that less than half of the funds are slated for investment in metropolitan areas. The analysis suggests that these transportation investments have been selected based on formula as opposed to what the American economy of today looks like.

As I’ve recounted at the Cents of Place in the past, the nation’s 100 largest metropolitan areas:

• Use 12% of the U.S. land area;

• House and employ 65% of our population;

• Generate 78% of patent filings; and

• Create 75% of total U.S. economic activity.

The report shows that the Minneapolis-St. Paul metropolitan area, while producing 1.36% of the country’s economic activity, is the location of 0.72% of the transportation-related stimulus projects authorized. Readers will note that the seven-county metro area contains just 12% of the state’s total lane miles. So doesn’t it make sense that stimulus funds reflect lane miles?

In its most succinct form, the answer may well be no. Here’s why: The federal stimulus legislation will provide capital grants to build, renovate, and replace transportation infrastructure – but it does not fundamentally address how state and local governments will pay for maintenance and operations. Over 87% of Minnesota’s total lane miles are county, township and city streets, paid for from limited state and local sources. Overbuilding may create long-term costs that will stifle prosperity in greater Minnesota, not the reverse.

Just ask my colleague Chuck Marohn, President of the Community Growth Institute, who provides planning and zoning expertise to small towns across Minnesota. In recent weeks, Chuck has blogged extensively about how and why our current approach to locating infrastructure investments is financially unsustainable. Moreover, it undermines the quality of life in communities like Brainerd, Minnesota, where Chuck grew up.

In metropolitan areas, the higher concentration of economic activity will allow for the funding of ongoing maintenance of road, rail and other systems, which will in turn bolster the metro economy as well as the statewide economy. Future stimulus funding, and the coming debate about a new federal transportation bill, ought to be designed in this light.

Photo courtesy of Resedabear/Flickr: http://www.flickr.com/photos/resedabear/ / CC BY 2.0