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improvements, and the relative costs of various design options. The potential costs and impacts on neighborhood character are significant. Residents should have the opportunity to evaluate and compare some "shared street" options without sidewalks, and some narrower driving lane and on- street parking options. Some communities and guidelines are now suggesting and installing roadways as narrow as 14 feet wide for two -way traffic (18 feet of "drive- able" surface counting edge treatments). Also, permeable pavement options need to be considered. The use of permeable paving could reduce roadway runoff and help filter out pollutants, reducing or eliminating the need for additional stormwater facilities. Residents are also interested in "context sensitive" designs that preserve existing large trees, something that also has value for stormwater management. 3.5.3 Development standards This section states that flood control development standards were not selected for implementation in other Basin plans completed in 2002, for various reasons. The text also notes that detailed cost comparisons were done in conjunction with the other Basin Plans, showing that it was more cost effective to use public capital improvements, not a combination of public improvements and requirements on developers to address on -site storage. It is not explained why the same conclusions from other Basin Plans, or the rather dated cost analyses, are assumed to apply to our RR -SC Basin today. It is also not clear how total costs of public capital projects can (or should) be compared with costs to private developers. At the least, more explanation is needed to justify why these earlier data and conclusions are relevant to the RR -SC Basin and this Basin Plan. The text notes that many flooding problems in other basins are caused by "existing developed conditions ", and concludes that these problems need to be addressed by new (public) capital projects (instead of new development standards). It seems that other conclusions are equally reasonable. If existing (private) development causes flooding, then doesn't this suggest that development standards DO need to change to prevent similar flooding problems in the future? Also, shouldn't private property owners be required to address existing problems on their property, rather than new public projects having to be sized to handle their runoff? Portland's Stormwater code encourages, and in some cases, requires stormwater retrofit projects for private property. Eugene's could do the same. In any case, at least parts of the RR -SC Basin are significantly different than other Basins. Many areas in our neighborhood rely more on on -site stormwater infiltration and (non - structural) natural infiltration. We also have a relatively high groundwater table, and many people have and use irrigation wells. Current City -wide stormwater standards allow, but do not encourage or prioritize dispersed, on -site stormwater management. City stormwater codes also do not require protection of natural hydrology, nor offer enough non - structural choices for accomplishing on -site infiltration. We do not believe that existing City -wide stormwater standards or programs to encourage LID practices are sufficient to protect natural drainage, groundwater recharge, or surface water flows needed to maintain stream ecology in our area. Surface water flows (Flat Creek, Spring Creek) have already been altered by existing development. Also, if projected total impervious surface in the Basin could be reduced via new development standards, it seems that would reduce the few modelled and observed flooding problems throughout the system and allow some of the proposed public (flood control) capital projects to be smaller in size. Here are some of the low impact development standards or methods that we think need to be required or promoted in our Basin, and that need to be evaluated in this Basin Plan: * prioritization of on -site infiltration (as in Portland) * prioritization of non - structural Best Management Practices, including