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Capital Hill PUD Traffic Safety Analysis (14-020) March 3. 2017 distance. Existing trees and shrubs within the right-of way along the east edge of the right-of way to the north and on the inside of the curve at the west edge of right-of way to the south limit the visibility of the existing approaches from the observation point within the driveway. The intersection sight distance can be improved with removal of trees on the inside of the curve within the right-of way to the south and along the east edge of the right-of way to the north. Capital Drive ends approximately 230 feet north from the observation point at the existing north driveway for motor vehicle travel, and there are approximately three residences north of the this driveway (low approaching traffic volume). In addition to the potential for improvement to the available sight distance and line of sight with tree and vegetation removal, the significance of the horizontal curvature to the south, will result in drivers traveling at less than mid-block speeds approaching the driveway (based on similar curves with posted advisory speeds on the roadway) and would reduce the AASHTO recommended intersection sight distance to 145 feet assuming the posted curve advisory speed of 15MPH can be assumed to be appropriate to substitute for the 25 MPH statutory speed. The existing south site driveway is located on the east side of Capital Drive approximately 150 feet north of the intersection at Cresta De Ruta Street, and is depicted on Figures 3 and 3A of Appendix B. The available intersection sight distance to the left from the observation point at the site driveway was measured as 235 feet, and to the right was measured at 200 feet with the planned right-of-way improvements, grading, and clearing at the top of bank. The potential line of sight availability and intersection sight distance is limited by horizontal curvature of the roadway in both directions. To the left (south) the roadway is on a down gradient from the driveway, and to the right (north) is on an up gradient. With horizontal and vertical alignments in both directions from the driveway, approaching drivers on Capital Drive will not be traveling at full mid-block statutory speeds, and will likely be traveling nearer to the posted curve advisory speed of 15 MPH, in which the AASHTO recommended intersection sight distance would be reduced to 170 feet assuming the design speed is consistent with actual conditions. The narrowness of the traveled way and the character and function of the section of Capital Drive fronting the site are similar to nearby existing constructed roads in the Fairmount and Laurel Hill neighborhoods. Roadways such as Sylvan and Cresta De Ruta streets, Madrona, Woodland, Highland and Malabar drives, and sections of Spring and Fairmount boulevards feature similar streetscapes to Capital Drive. The narrowness of these streets, with intermittent on street parking, horizontal and vertical alignments that work to lower travel speeds and calm traffic and to function similar to a "queuing street" is discussed in the August 1996 Eugene Local Street Plan and the February 2016 Public Improvements Design Standards Manual, which refers to the November 1999 Design Standards and Guidelines for Eugene Streets, Sidewalks, Bikeways and Accessways. The narrowness of Capital Drive does not necessarily require the time gap for left-turns from stop to match the AASHTO assumed 7.5 seconds utilized in the intersection sight distance equation for vehicles to enter the major street from a stopped position at the driveway for crossing of one standard 12-foot wide travel lane to turn left as is built into the AASHTO equation. The narrowness of the road and presence of intermittent on street parking and horizontal and vertical alignment features calm traffic speeds on Capital Drive. Most importantly, approaches to the site driveways have adequate line of sight of the roadway to meet the AASHTO recommended criteria for stopping sight distance on the major street approaches to each of the existing and proposed driveways, should a driver at the observation point depart the driveway during the time which an approaching vehicle surpasses the recommended © Branch Engineering, Inc. Page 15