while local circulation systems and land-development patterns should not detract from the efficiency of bordering major streets (Section 6.02.00(A)). The code requires platted subdivisions to provide adequate vehicular and pedestrian access for each parcel and indicates that access management strategies (e.g., control of driveways, intersection placement, full or partial control of access) may be necessary to ensure that local circulation systems do not detract from the efficiency of major streets. It states that land development should occur so that no parcels require direct access to major streets (collector roads). Section 6.02.01(B(4))
4.3 Corridor Management and Street Network Development
A balanced roadway network consists of a combination of major arterials, minor arterials, collectors and local streets. Ideally, arterial roadway networks are developed in a grid pattern with a general network spacing of ½ mile for continuous 4-lane roadways (Williams, et al., 2014, Levinson, 1996). This pattern improves traffic performance by distributing traffic across the network and reducing pressure at intersections. In addition, “street spacing and scale are interrelated. In general more continuous streets (i.e., closer spacing) is better than fewer,” (Levinson, 1996). Four-lane roadways are less intrusive than six lane roadways, better integrate into surrounding areas, and complement urban placemaking and complete streets concepts. Collector roadways round out the grid by connecting roadways of a similar or higher function. Although some six-lane roadways may be needed to accommodate traffic, they have a number of issues. Long spacing of 6-lane arterials leads to high turning volumes at intersections. Wide arterial roadways are also less desirable for pedestrians and cyclists. Six-lane roadways in urban areas are generally the result of widening existing arterials to compensate for the absence of a balanced network of roadways with supporting circulation systems (Williams, et al., 2014). Long intersection delays occur where a six-lane arterial intersects another six-lane arterial, often requiring grade separation or alternative intersection designs to resolve. Continuation and connectivity of the existing local street system along major roadways is also important to provide accessibility for all modes of transportation (see Figure 70). Dead end streets, cul-de-sacs, and gated communities force more traffic to use major roadways even for short local trips. Fragmented street systems also impede emergency access and local bus transit service, and increase the number and length of automobile trips.
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