There are many reasons "too much" parking is bad for a downtown:
- Parking raises the cost of new development, which means less of it. This may be no big deal for a city with a built-out downtown, but it is a big deal for Austin, which devotes so many downtown blocks to surface parking or stand-alone garages.
- Parking not only raises the cost of new development, but it limits their size and density. An on-site garage can only be so big to be practical. A developer who wants to provide enough on-site parking to cover peak demand must first figure out how much parking he can build; only then will he know how much he can build of whatever it is he wants to build.
- Parking garages and surface lots blight the streetscape, triggering a negative feedback loop: the surface lots and garages make streets less attractive to pedestrians, which drives the pedestrians away, which reduces demand for pedesestrian-oriented retail, which makes the streetscape even less attractive for pedestrians, etc.
- Subsidized parking -- i.e., parking provided below cost -- distorts the market, encouraging an inefficient mix of driving and transit use.
- Plopping ever more parking dowtown increases congestion. The amount of land devoted to streets is fixed. The amount of parking is not. Increasing the number of parking spots but not the amount of street space means more cars per square meter of street, which in turns means more congestion. (This very interesting paper (pdf) by Michael Manville and Donald Shoup explores this argument in depth.)
- Parking garages and surface lots are butt-ugly.
There is one and only one counter-argument, but it should be taken seriously: because we are so car-oriented, having too little parking will simply deflect businesses and shops away from downtown. No matter how nice the sidewalks or inviting the buildings, a street is not pedestrian-friendly if it has no pedestrians.
I'm always willing to consider more evidence, but I don't think this argument holds for Austin. There are good reasons to believe Austin's downtown parking market suffers from market failures.
But an even simpler analysis is to compare Austin's dowtown parking supply to other cities'. If other cities get by with less, perhaps Austin could, too.
And there is evidence that other cities are getting by with less. The Manville and Shoup paper includes a very interesting chart (based on a 1999 study), which I've adapted below. It estimates the number of parking spots per job for various cities. It did not include Austin, but I borrowed the Austin data from Wilbur & Associates' 2000 parking study (pdf).
Obviously, many of these cities are oranges to Austin's apple. Foreign cities are not reliable benchmarks. Nor are old, dense American cities with extensive rail or subway networks. But there is no obvious reason why Houston, Los Angeles, Denver or Sacramento need less parking per worker. (And since this chart is based on 1999 data, neither Houston nor Denver's light rail accounts for the difference.)
The Wilbur & Associates study provides another comparative analysis. Again, Austin supplies significantly more parking per downtown worker than other cities (excluding San Antonio, which I suspect has such a high ratio because of job losses downtown).
Again, these are 2000 figures. Austin has added thousands of parking spots since then, excluding the many thousands added by the new condo developments.
The new condo dwellers have increased demand for parking downtown. But that demand has been absorbed (and then some) by on-site parking. I'm flummoxed why downtown needed a few thousand more commercial spaces.
I think this is evidence that Austin's downtown parking market is broken. The cause could be lender-required minimums, underpriced curb parking, the inefficient allocation of taxes to capital rather than land, or all of above and others. With the lull in commercial construction, we have a chance to diagnose the problem and develop a cure before the next wave.