Item A: Low Impact Development: Results of Review

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site, which is intended to regulate minimum density of development. A maximum ratio is not set but rather is influenced by market demand for location, size and height of buildings. It was noted that other communities may use maximum FAR a mechanism to regulate building height and mass in relationship to a development site – building height is directly regulated in Eugene Code. A minimum FAR may tend to increase lot coverage with ISA. Incentives could be developed to allow a lower FAR if pervious areas or ISA reduction techniques or other LID practices such as green roofs are used. Council direction was to consider LID practices consistent with densification policies and code provisions; within these parameters adjustments to FAR have a relatively low potential for increasing use of LID practices. Parking ISA – Low Potential Currently all required parking is allowed to be compact in dimension and limits are placed on the minimum and maximum number of parking spaces allowed. Reductions to minimum required parking are allowed under certain development types and conditions. Greater reductions to minimum parking requirements risk parking demand exceeding parking capacity on a development site, impacting parking in adjacent areas. Higher density objectives resulting in a greater number of minimum required spaces, coupled with optimal use of available site area, may present barriers to minimizing ISA, thus a low LID potential exists in this area. These limitations in potential could be partially offset by use of pervious pavements for parking areas (see Parking Standards below). Parking Standards Parking standards regulate the physical characteristics of required parking, including surface types, landscaping, and maximums per size of development. Medium Potential: Expand on acceptable pervious surfaces allowed. Standardize planting allowed that will meet landscaping for parking requirements as well as those required per stormwater development standards. Barriers: complexities of implementing changes to regulations and existing standards; potential to increase both project and on-going maintenance costs; competing objectives between the two types of planting requirements. Elements of parking standards were reviewed in further detail as follows. Parking Surfacing – Medium Potential All parking areas that contain three or more parking spaces, except those in conjunction with one- or two- family residences, are currently required to have durable, dust fee surfacing of asphaltic concrete, Portland cement concrete, or other approved materials which may include (but don’t require) pervious paving materials. In addition, new parking areas are required to meet the stormwater development standards which encourage LID practices. Landscape requirements for parking contain planting requirements somewhat compatible with stormwater development standards are but may have competing objectives; some potential exists for better-integrating landscape standards. Potential also exists to refine the impervious surface types allowed and required for parking areas. Requirements for use of pervious pavements would necessarily be limited to areas where soil and site conditions allow and may present higher construction costs; while long-term viability of pervious pavement as an LID technique requires commitment of ongoing maintenance resources. Parking Space Thresholds – Low Potential Current maximum off-street space count does not allow the number of spaces for nonresidential uses to exceed 125% of the minimum space count, allowing only a modest amount of additional parking area beyond the minimum required. Setting a lower maximum space count helps constrain total ISA. As the standard is currently structured, lowering minimum space count in turn lowers the maximum space count allowed since the maximum is expressed as a percentage of minimum. Minimum space count is somewhat flexible and has been reduced in the recent past; however, risks and impacts of lower minimum parking space requirements limit the LID potential of this area of regulation as currently structured. September, 2008 City of Eugene LID Report, Page 7 of 26