Streets & Blocks

I. The rear alley Category: Circulation Subcategory: Thoroughfare types The practice of having different ways into buildings for different kinds of activities is age-old. Consistent provision of service-ways within an overall urban plan, however, dates only from the mid-19th century, with the coming of water and sanitary sewers. The rear lane is the older, more informal version that today exists mostly towards the rural ends of the Transect. It will be discussed in the next Technical Page. Like the lane, the alley is a multipurpose, mid-block service route, but occurs towards the urban end of the Transect. In cities unequipped with alleys, all users — parked cars and street sweepers, mail delivery and dog walkers — compete for the same frontage. Access management becomes critical. In New York, which has few alleys, the average building supervisor has the space-time skills of an air traffic controller. Without alleys, the complex vitality of city life too often becomes an aggravation. The alley is the under-appreciated ally of the pedestrian-friendly street. By accommodating parking and parking access, utilities (including today's altar-scaled electrical transformers), trash and trash pickup, the alley allows the street to be more hospitable. Sidewalks are not threatened by cars backing out, street trees are not buzz-cut to clear utility wires, and nonresident parking becomes a less contentious issue. The alley also has virtues in its own right. Besides multiplying the secondary pathways through the urban fabric, and allowing for messier kinds of household work and casual neighborliness, the alley is key to provision of less expensive dwellings. These broaden the range of household incomes in a neighborhood. They provide rental units, the income from which also supports higher mortgage qualifications for the primary dwelling. They also can serve to keep members of an extended family tolerably close by. Living on the alley also provides the human surveillance that makes it safe. The downtown core alley should be paved across its width, used by both vehicles and pedestrians. Drainage direction and surface permeability vary across the Transect. The building-to-building width should provide room for both dumpster service and vehicle backout. In general, an “H” pattern for a block is more desirable than a “T” or “I”, as it blocks the through view as well as allowing for easier mix of building types.