Home Sustainable Land Development Today February 2007

Technology Utilizes Nature’s Design

Written by Nicholas Bugosh

Thursday, 01 February 2007

Natural landform design controls erosion, protects water quality, and enhances property values without expensive gimmicks (and saves money). Today’s land developers are faced with many challenging criteria when they disturb the land. They must reshape the land to meet the development need, and simultaneously address land stability issues, meet water quality standards for runoff waters, and satisfy the demands of buyers for open space, green belts, privacy, sunlight, view lines, etc. Many of these criteria are not met by traditional land development methods that are concerned primarily with fitting the maximum number of lots in a development. Traditional storm water control has been to collect and route runoff in pipes and ditches, and discharge it to a receiving water or detention pond as quickly as possible. Problems result when the disturbed land is not shaped to convey runoff without erosion, and when runoff conveyances ignore natural stream flow dynamics. An erosion-control product industry has emerged to sell developers a wide array of products that can be added to the land development to reduce these problems.    Traditional storm water conveyance passes runoff, but does not enhance other development values. The old design methods require long-term maintenance of concrete, culverts, gabions, and other artificial controls. The resulting landform is a bleak landscape that provides minimal diversity for plants and wildlife, and is not visually satisfying. An alternative approach to this scenario of disturbing the stability of natural landforms and then adding expensive measures to try to fix the resulting problems is now available.  A landform design software called Natural Regrade with GeoFluv™ extends fluvial geomorphic (literally landforms made by flowing water) principles to upland landform design. It helps the land developer or designer to create a landscape design that mimics the functions of the natural landscape that would naturally evolve over time. The result is a stable hydrologic equilibrium ... naturally. Runoff in a natural channel provides a green-belt of open space within the land development. The essence of the GeoFluv™  approach is to identify the type of drainage network, i.e., stream channels and valleys, which would tend to form over a long time given the site’s earth materials, relief, and climate to achieve a stable landform, and to design and build that landform. The resulting slopes and stream channels are stable because they are in balance with these conditions. They are a design alternative to uniform slopes with artificial water conveyances and expensive erosion control gimmicks. The natural landscape alternative helps the land developer enhance property values by varying lot view lines, sunlight exposures, and open-space areas while controlling erosion and sedimentation. Rather than fight the natural forces that shape the land, GeoFluv™  helps the user create a landscape that harmonizes with these forces. The resulting landforms are functional and stable against erosion. This stability is achieved without artificial materials or structural controls and is thus maintenance free. The irregularity of the naturally-designed landform provides landscape diversity that benefits plants and wildlife. Additionally, the software has design tools that the land developer can use to optimize lot view lines and sunlight exposures that can help to enhance the value of every lot. The Natural Regrade software replaces lengthy and tedious manual calculations with fast, efficient computer-aided design. The user-friendly Natural Regrade software frees the user’s creative design energies. The software allows the land developer to view topographic maps and three-dimensional images of the resulting landscape. This three-dimensional imaging capability can be a powerful tool for presenting the proposed development to zoning commissions and other regulatory authorities, investors, and potential clients. The developer also gains the ability to perform one-button volume and cut/fill material balance calculations for proposed designs with instant colored-coded feedback. This ability to harness computer calculation speed helps the land developer to make rapid evaluations of many landscape design alternatives to select the optimum landscape design for the proposed land use, construction costs, changing development plans, customer’s desires, etc. After considering all these benefits of the GeoFluv™ approach, the developer may be wondering, “When the landform is designed in this manner, how well does it perform?” The following example addresses that question. The landform shown in the following images was made using the GeoFluv™ approach. The landform was constructed in an extremely erosive environment, within about 200 miles of the Grand Canyon (which many consider to be the largest erosional feature in North America).    The photo on page 16 is a view of land graded to a GeoFluv™  design before November of 2003. Close inspection will reveal construction equipment markings on the slopes, but there is no rilling or erosion. This landform has no topsoil, no vegetation, and no artificial erosion controls. The top of the ridge is 6,010 feet elevation. The image was taken in January 2005, after the site endured the 2003/2004 snowmelts, 2004 monsoon rains, and the 2004/2005 snowmelts. The photo on this page is a view of the same area after application of topsoil and seeding. The vegetation is just starting and mostly annual plants are visible, just the first season’s growth. The image was taken in mid-September of 2006 following a 200-year rain event (three-hour storm) that hit the site in June. Again, no erosion, but a stable, functional, and beautiful landform! Does this land appear to ever have been disturbed? The open-pit of a coal mine formerly occupied this site! Whatever kind of land development projects you undertake, valuable residential view lots, golf course design, brownfield developments, etc., you can visualize them in this landform, or any of the infinite number of alternative designs that you can make with the GeoFluv™  design approach. Natural Regrade is ideal for integrating with Global Positioning System and machine control technologies, for example Carlson Grade, to simplify and speed construction and reduce costs. The need to survey and stake the designs in the field is eliminated using these technologies. The GeoFluv™ design approach is award-winning, including U.S Department of Interior “National” and “Best of the Best” 2004 reclamation awards and adoption as US Department of Interior TIPS ‘Core Software’ in 2006. LDT