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3 of 7 Traffic speed data on Foothill Road is collected on a regular basis. Over the last 15 years, the speed has been consistent with 85% of drivers driving at or below 45 mph and 99% of vehicles driving below 55 mph. Sight Distance The sight distance to the south is 630 feet. This distance is measured from the proposed project driveway to the point where a vehicle is first visible as it comes around the curve at Puri Court. The approximate sight distance to the north is 550 feet. This distance is measured from the proposed project driveway to the top of the vertical curve located at Equus Court. The sight distance looking to the north may improve with the project, as the trees lining the roadway will be removed, which could add 30-40 feet of sight distance. • Stopping Sight Distance 1 for a vehicle traveling at 45 mph is 360 feet. • Intersection Sight Distance 2 for 45 mph is 500 feet. Thus, the visibility to the north and the south meets the required intersection sight distance of 500 feet. The Federal Highway Administration’s (FHWA) Handbook for Designing Roadways for the Aging Population evaluated intersection sight distance for ages 55-80 years old. The handbook provides greater detail on intersection sight distance and the concept of gap acceptance for older drivers, in particular suggesting that older drivers need a larger gap between vehicles to feel comfortable making left turns. It notes that for the average driver, an acceptable gap in vehicles is 5.5 seconds, meaning that a typical driver wanting to turn left onto a roadway will want 5.5 seconds between vehicles. This time between vehicles progresses linearly with age, and older drivers (75+) may need up to 8 seconds to have a comfortable gap for left turns. Although field observations conducted by the FHWA identifies a metric of 5.5 seconds, the accepted standard for intersection sight distance evaluation uses a larger 7 second gap. This larger gap provides easier access for larger vehicles (delivery vehicles) and older drivers that exercise caution and turn at a slower speed. 1 This value is used for drivers on Foothill Road to recognize an object in the roadway and come to a stop before striking it. 2 This number is used to determine the distance needed for a vehicle exiting a side street to look left, right and left again to make a left turn onto Foothill Road.