Issue link: https://read.dmtmag.com/i/35322
doesn’t ensure profits. The world is full of high-density failed projects. This next example is a comparison between a con- ventional subdivision and the same site planned with Prefurbia techniques. The original approved plat (Figure 2) used standard lFigure 2. An original CAD drawing of a subdivision plat was approved in New Braunfels, Texas. CAD configurations to automate the subdividing of land. Visualizing the terrain by contours, this linear approach doesn’t follow the organic flow of land that nature created. The linear approach, however, does produce a fast plan that adheres to minimum dimen- sions. The original plan uses CAD to produce lines and arcs that form the definition of new property lines. What’s missing is geospatial information: the Street paving is reduced by 20 percent, and total driveway volume is similar due to attention to efficient design. But the density is the exact same 2.98 homes per acre. And the 8,800-square-feet park could be used for low-impact drainage, further reducing the impact on the environment. This is one example of how gains can be made by thinking outside the confines of a minimal box. This also is an example of a cul-de-sac that could instantly be generated by a software program vs. using preci- sion geospatial technology to find better design solu- tions—not robotic solutions. Real Geospatial Information The success of any land plan clearly depends on the economic bottom line: profits. The land plan is the developers’ business plan. Achieving a density target shapes that form the surface area of street, lots, driveways and other elements that form economic and environmental impacts. The CAD systems that engi- neers and surveyors use to subdivide land fall short of spatial information needed to verify design efficiency. Conversely, GIS solutions that are polygon based fall short of the accuracy and computational flexibility needed to design beyond minimums. Prefurbia uses new spatial technology and meth- ods to model new planning forms. Instead of a linear approach, the housing and development conform to the land’s natural flow in an efficient manner. The reap- proved Prefurbia plan is seen in Figure 3. • Flow: The new model creates a flowing and con- nective street pattern where residents and guests encounter only one turn or less to arrive and depart. The previous layout required multiple “accelerate-stop-turn” cycles, resulting in terrible flow, which wastes time and energy in vehicular transit. • Pedestrian system: Encouraging a stroll over a drive isn’t accomplished by installing two narrow (four- foot-wide) strips of walk parallel to the curb. On the origi- nal plan, vehicular flow was lacking, so pedestrians who follow the street wouldn’t have a better situation. In the new plan, six-foot-wide meandering walks add beauty, eliminate monotony, and keep people and vehicles separated. An eight-foot-wide walk cuts through a block to add emergency-vehicle circulation if ever needed. • Meandering Streetscape: The lot width at the front setback minimum was 25 feet. Every home is set at a unique position to form meandering arcs that undulate separately from the street’s shape, with the minimum being 25 feet. Every lot has more space, and the lots offer more home expansion opportunities far above a rectangular shape that can be automated at the press of a mouse button. • Density: The original CAD-created subdivision was lFigure 3. The approved preliminary plat from Figure 2 is modified using Prefurbia’s geospatially empowered methods. 24 GEO W ORLD /JUL Y 2O11 approved, but there was a deficiency in the drainage ponds. Taking the resulting revision into consideration, both essentially have the same density. • Harnessing spatial coordinate geometry: Using a performance planning system (PPS), precision spatial and Community Development