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the same number or perhaps more lots possible in conservation design.
LOW IMPACT DESIGN
     One tool of conservation design is low impact design.  The two are not synonymous.  Low impact design replaces traditional large, centralized stormwater management ponds with smaller, decentralized water quantity/water quality control devices, like rain gardens.  Traditional storm sewer pipe systems give way to ditches.  The goal of the stormwater management system in low impact design changes from the most rapid evacuation of water from the site of traditional design to a series of decentralized detentions, multiple opportunities for natural treatment and more natural cycling (evapotranspiration, percolation, etc.).  Small spaces are opportunities for rain gardens and roof gardens to provide more natural water quality in low impact design.
    The traditional best management practices (BMP) ponds are not performing as well in the real life beyond our drafting tables as they do on paper, particularly from a qualitative perspective.  The rezoning exhibits showed more colorful wet ponds, with lush greenery and happy residents with their arms inexplicably in the air (waving at each in apparent ignorance of their close proximity).  And does that exhibit show fish jumping?  Aren’t most BMP ponds dry part of the time?  Real life wet pond inspections are more disappointing.  Where are the fish?  What is more important, the sediment is in apparent ignorance of our equations that should direct its settling rate?  At least the residents are waving.  They wave us over to hear their complaints.
    Despite our degrees and credentials, nature cycles and treats water better than our experimental alternatives, the effects of which have been observed for very few thousands of years.  Ironically, the low impact design approach can work to the developer’s economic advantage.  Drainage ditches and roads with shoulders are less expensive than underground reinforced concrete pipe and roads with curb and gutter.  Ponds, and pond maintenance especially, are more expensive than rain gardens.  Home values increase with the high aesthetic value and increased quality of life that a conservation design/low impact design neighborhood offers.
ENTER THE AUTOMOBILE
The driving force behind traditional design was the automobile, because after all, autos created suburbia in the first place.  In the design of the tradition suburban neighborhood, all roads lead to the most efficient and most rapid commute.  Wide roads, sweeping curves, and plenty of parking dominate the landscape, or more accurately replace it.
    Conservation design demotes the automobile as a
driving force.  The minimum parking required is proposed.  What pavement remains can be made more environmentally compatible with pervious pavement systems.  Parking medians’ curb and gutter schemes are replaced by rain gardens.  Rather than start with the commuter’s speed as the predominant design factor, speed is reduced by the narrow roads and sharp turns that cost fewer trees.  And finally, pedestrians and bicyclists are now important considerations in the design process, no longer the unwelcome afterthought of traditional design.
IMPLEMENTATION BY LOCAL GOVERNMENTS
     Once it decides to adopt conservation design and low impact design, how does a local government go about the implementation of such radical change?  The planning document (five year plan, 20 year plan, general plan, or a similar document) is the first location in which we would expect such a sweeping change to appear, and was indeed the first location for its official status as a policy in Loudoun County.
     The entire government process is best enhanced by the earliest involvement of both the citizens and affected business representatives, shaping policy with their areas of interest and expertise.  The earliest meetings were workshops.  The tenants of conservation design were discussed, and blank site plans were used for practice designs.  In these exercises, teams of workshop attendees attempt to design both residential and commercial sites to a “strawman” zoning ordinance using sample densities, setbacks and other standards.  The most valuable phase of the workshop is the final discussion, in which the pros and cons of various sample standards are weighed.  
     Some of the sample zoning and design standards of the workshop strawman rules made any development nearly impossible.  For example, we cannot have both the clustering desired in conservation design while still retaining the large building setbacks of traditional design.  We cannot have the degree of saved trees areas desired in conservation design while still retaining the large, sweeping roads of traditional design.  In other words, we cannot simply add conservation design requirements; we must also relax or eliminate conflicting provisions.
CHANGING PLANS, ORDINANCES, AND MANUALS  
     The general plan policy and documents that follow it were definitely shaped by lessons learned in the workshops   In its final form, the revised general plan adopted by the board of supervisors redirected the staff’s strategy to conservation design in their work on rezoning applications, special exceptions and to a lesser degree those applications less subject to negotiation.  
     Implementation of any new policy can generate spinoffs.  One feature of