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ee ee . . The 30 foot right-of-way width I suggested for one-way rQadways assumes a 16 foot pavement width, ten feet for a roadside swale and four feet for tree planting. The 16 foot width allows for passing a disabled vehicle. The 30 foot right-of-way reflects the idea of a minimum, rather than optimum width: it recognizes that a one-way roadway need not be center-crowned for drainage, but instead, may be cross-pitched to one side. Ten feet should be plenty of swale room for low volume residential access streets. Also, this right-of-way dimension is actually larger than that recommended for low volume urban section access streets (24 feet wide - yes, right-of-way, not pavement) in Residential Streets, Second Edition (1990), jointly published by the American Society of Civil Engineers, the Urban Land Institute and the National Association of Home Builders. Subsection (4)(C)(9) on Cul-de-Sacs. The addition of the word outside simply makes it clear that the standard is to be applied to the radius of the outside edge of the pavement rather than to the inside edge of the pavement. Some places have 45 or 50 foot radius standards. Those familiar with such cases might think the radius is intended to apply to the inside radius. I added a reference to maximum cul-de-sac length in recognition that this code may be adopted in more restrictive form by a given locality. This language sets up the idea that length ought to be related to traffic generation, not actual distance. Contrary to conventional wisdom, what counts in cul-de-sac length is trip generation, not the length of fire department fire hose or water main looping or snow plowing. It is the number of units served that determines trip generation. Each unit will generate up to 8 to 10 trip ends per day. That means each unit will be responsible for 8 to 10 counts of Average Daily Traffic (ADT). The maximum of 26 units I suggested translates to 208 to 260 ADT. This is a reasonable cap for residential access streets. Hopefully, the municipalities who seek more stringent standards on cul-de-sac length will take direction from this language that the appropriate measure is trip generation, not actual length. It seems to me that this is an especially appropriate measure for an open space development ordinance that has no specific street frontage requirements for lots. Addition of Subsection (5) on urban road sections. This modification would contribute greatly to the goal of preserving the rural character of Washington County stated in Section 4.1(7). Every year I get three or four calls a month from homeowners who are dismayed that the local municipality is "upgrading" the street in front of their homes by converting a rural section to curb-and-gutter with storm sewer. They want to know how to stop it because it they understand that it will ruin the rural character of where they live. The curb-and-gutter is the symbol of banal suburban development - in most cases it is completely unnecessary and creates more storm water problems than it solves. I suggest that, like much of Connecticut, Washington County ban the use of curb-and- gutter streets outright in new subdivisions. The language I have suggested limits the ban to street segments where the lot frontages average less than 50 feet and the lots access the street via driveways. Exceptions should be allowed only by appeal to the County Planning Commission. Where frontages average less than 50 feet, it is difficult to maintain overland storm water handling devices along the roadside with driveways. It is no problem where alleys are used instead of driveways. Many designers believe that even 50 feet is too small because there is almost no swale length between driveways and a lot of culverts (one for every driveway). They often say there are so many culverts, they are almost a connected pipe anyway, so why not put in storm sewers. Actually this is not true. At the 50 foot frontage, a driveway would require about a 25 foot long culvert, leaving 25 feet for ponding. This type of pacing of culverts and short swale segments is actually very good from a storm water management Rationale for OSD changes 6 Sykes