StructureHub

Why not?  ”Normal” cities have abandoned rail-beds ripe for transformation into green space.  Metropolitan Phoenix has the southwestern equivalent: an extensive network of unsightly drainage canals, which course through neighborhoods and link the area’s major cities (Phoenix, Scottsdale, Tempe, Mesa, Gilbert, Glendale, Chandler).

Of course, unlike the old rail-beds, the desert canals still serve an important, albeit rarely called upon, function, the nature of which compounds the challenge of transforming this concrete-lined necklace into an attractive park-scape.  For one, the canals’ operate on a feast-or-famine cycle; most of year they are nearly or completely dry, but must nonetheless possess enough volume to safely channel large quantities of water, deposited by rare (but recurring) rainstorms.

As you might expect, the intractability of this problem - designing attractive park space along an unattractive ditch that must be preserved as such - led to a design competition.  ASU and the Phoenix chapter of the American Institute of Architects recently announced the identity of 13 finalists (3 of whom declared “most outstanding”) from the 2009 Canalscape Symposium’s roughly 70 entries.  Beginning November 10th, the entries will be exhibited for one month at the ASU Art Museum.

I’d post a snapshot of some entries if I could find images online.  But the competition website and museum’s exhibition page lack such helpful information (here is a brief write-up for those not interested in graphical representation).

One thing is assured: whatever designs are revealed for Phoenix’s canals (or Los Angeles‘ for that matter) will differ from other similar park systems.  I suspect that the most successful design will rely heavily on shade-giving desert vegetation to soften the feel of the concrete-lining and create human-scaled intimacy, and on bike/walk paths linking sections of concentrated activity (e.g., wide patios and space for stores/restaurants where canals bypass existing commercial hubs).

Image courtesy of peterhowe