§ 68.404. Connectivity Index.

In accordance with GMP Future Land Use Policy 4.2.5, and consistent with the GMP Transportation Element, the City shall combine the mobility of the traditional interconnected street pattern with the safety, security, and topographic sensitivity of the conventional or contemporary network. Such a hybrid network features short, curved stretches that follow the lay of the land or contribute to good urban design, as well as short loops and cul-de-sacs, so long as the higher-order street network is left intact.

"Higher-order" means arterials, collectors, and sub-collectors that carry through traffic. An acceptable individual project master plan may feature interrupted grids of short street ending at T or Y intersections, traffic circles or squares/parks. By design, local streets may carry some through traffic, but the truncated nature of local streets means that traffic moves more slowly and the heaviest volumes are diverted to higher-order streets.

A simple measure of connectivity is the number of street links divided by the number of nodes or link ends (including cul-de-sac heads). The more links relative to nodes, the more connectivity. A connectivity index of 1.4 to 1.8 represents an acceptable street network in the Southeast Plan area. The optimal connectivity index for a perfect grid network is 2.5. This is the procedure for calculating the connectivity index:

(a)

Count the number of nodes. Nodes are any point of intersection of two or more roads or any cul-de-sac ends.

(b)

Count the number of links. Links are the segments of road connecting nodes. To properly calculate the connectivity index, you must first include the first link beyond the last nodes.

(c)

Use the following formula to calculate the connectivity index: links/nodes = connectivity index.

Simple changes in design, such as removing cul-de-sacs and connecting the street-ends to other streets, can bring about significant changes in connectivity index scoring. The City shall utilize the connectivity index mechanism, in addition to other qualitative measures, to determine whether transportation impact fees can be reduced within the Southeast Orlando Sector Plan area.

(Ord. of 5-10-1999, § 10, Doc. #32070)