In a guest post at Kaid Benfield’s Switchboard blog (of NRDC), Rachel Sohmer very nicely describes the issues around street connectivity, using a childhood example about how the suburban dead-ends and cul-de-sacs made even short trips “as the crow flies” long given all the obstacles. The below figures show the difference more street connections can make.
Rachel gives an excerpt from a piece by Charlottesville transportation planner Hannah Tradwell:
Regardless of their size, communities can realize three major benefits from better connectivity: shorter trips; a wider variety of travel choices; and more cost-effective public services and infrastructure. Creating more direct connections shortens travel time, which effectively brings people closer to their destinations. With more available connections, community residents can get to schools, shopping centers, and other spots that may have simply been off their radar before — not because these places were too far away, but because they were too far out of the way.
I would definitely add parks to this list. Excellent parks are accessible parks. The way they interact with the street grid is integral to this. Take two parks in the Twin Cities, Minn. metro (but this could be Anycity, U.S.A.). One is Powderhorn Park in Minneapolis (below, left), surrounded by the grid and the other is Colonial Park (below, right) in the nearby suburb Burnsville. Nearly 100 percent of the first park is accessible by the grid, and the latter is at most five percent accessible via the streets. In this suburban environment with plenty of backyard space, this might work — but if we are to build more compact, walkable cities and densify our suburbs, the need for an accessible park more like the one on the left is much greater.