Laserfiche WebLink
r- <br />ANALYSIS <br />. Capacity Calculations <br />In general, level of service C is desirable on rural highways such as <br />" SH 133. According to the 1965 Hiohway Capacity Manual, level of service C <br />,- <br />is generally indicative of stable flow, operating speeds of 40 mph or above <br />r for uninterrupted flow on a two-lane highway, and a total volume for both <br />,. directions of travel reaching 70% capacity with continuous passing sight <br />distance, or 1400 passenger cars per hour under ideal conditions. <br />~-- <br />Using the 1465 Highway Capacity Manual, the maximum hourly volume of <br />~ traffic (or service volume) that any segment of the highway can carry <br />_" without degrading level of service C is calculated as follows: <br />- (Ideal carrying capacity of 2,000 vehicles/hr.) x <br />• (Working value for restricted average highway speed) x (Lane width <br />adjustment factor) x (Truck adjustment factor). <br />~ Average highway speed (AHS) is defined by the Highway Capacity Manual <br />L: as "the weighted average of the design speeds within a highway section, when <br />~"' each subsection within the section is considered to have an individual design <br />speed". The segment of SH 133 between Stevens Gulch Road and the train <br />loadout and silos was considered to have an AHS of 50 mph.* This segment <br />of highway was also considered to have passing sight distance of greater than <br />1500 feet 40~ of the time. Using the above limiting parameters, the working <br />r- value for restricted AHS is 0.38. <br />* Although this section of SH 133 is posted for 45 mph due to adjacent built-up <br />• conditions, the horizontal alignment only limits the section to 60 mph. The <br />vertical alignment limits the section to 50 mph in certain areas. <br />-12- <br />