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. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2006 PAVEMENT MANAGEMENT PROGRAM PAVEMENT SECTION DISCUSSI01>i The proposed roadway improvements for Siems Court, Ridgewood Road, Arden Place and Skiles Lane will include full reconstruction due to their deteriorated conditions, lack of curb and gutter and lack of drainage infrastructure. The proposed bituminous street pavement sections will be designed in accordance with flexible pavement design utilizing the soil R-values measured from the geotechnical analysis accomplished as a part of the soil borings. City standards also include a 12-inch sand subbase below the aggregate base. The sand subbase will provide enhanced pavement suppOli, pavement subdrainage and frost protection. Additional excavation, or subgradc excavation, may be required to conect poor soils in isolated locations as field conditions dictate. Compaction inspection of select granular subbase and aggregate base will include Penetration Index Method (PI Method), which will ensure proper compaction of roadway materials. The anticipated pavement cross section includes 4 inches of bituminous surfacing, 8 inches of Class 5 aggregate base and 12 inches of sand subbase. The sand subbase will be drained with perforated pipes connected to catchbasins. final pavement sections will be determined as a pati of the final design process based upon the soil borings and analysis of in place soils and traffic loads. See Exhibit A2 Typical Section. STREET WIDTH DISCUSSION All streets within the neighborhood, except Ridgewood Court, have been classified as "Special Case" in the Functional Street Classifications Map. Ridgewood Court is classified as an "Alley", which means its functional width is 12 feet. The functional classification recommends a 24-foot street width for "Special Case" streets; however the policy allows that streets may be narrower than 24 feet, depending on the sUlTounding neighborhood and topographical constraints. Below is a chart of street widths as measured, as recommended by functional classification and as proposed for the 2006 PMP project: Street Name Siems Court Ridgewood Road Arden Place Skiles Lane Ridgewood Court (Option) Ex. Width 25 24 24 24 12 Function 24 24 24 24 12 2006 PMP Recommend 22 22 22 22 12 The existing roadway widths measured from edge of bituminous range from 24 feet to 25 feet. The proposed roadway cross section will be 22 feet wide, measured face to face, for all streets. This equates to 23 feet 4 inches back of curb to back of curb and will allow the proposed to fit within the tight topographical constraints of the existing roadway. Throughout the neighborhood, trees and steep slopes close to the roadway force the proposed to match the existing alignment closely. The nanowest existing condition is near Arden Place and Skiles Lane where a large oak tree is located on the south edge of the road and a "bridge" driveway to the north. The distance between the two is approximately 25 feet. Although the proposed 22-foot width is slightly less than the recommended 24-foot width, the streets should function adequately for the low amount of traffic and parking pressure that they recei ve. Operations and Maintenance staff have been ORS 7