Sub-problem 3a - Page 4 of 9

ID# C103A04

Sub-problem 3a: Oversaturated Intersection Analysis

Data were collected for a typical post-football game period at the U.S. 95/Styner Avenue-Lauder Avenue intersection. Exhibit 1-27 shows the demand (flow rates in veh/hr) for the four 15-minute periods immediately following the football game:

Exhibit 1-27. U.S.95/Styner-Lauder Avenue Intersection Demand Volumes
15-min time period beginning	Eastbound			Westbound			Northbound			Southbound
15-min time period beginning	LT	TH	RT	LT	TH	RT	LT	TH	RT	LT	TH	RT
4:00 pm	40	55	175	50	50	75	100	815	45	40	700	55
4:15 pm	50	75	375	55	80	125	215	1,025	50	59	1,975	165
4:30 pm	30	75	125	45	75	115	20	975	35	55	1,200	145
4:45 pm	45	60	175	55	85	150	145	1,015	45	50	1,350	130

How will the intersection perform, under both signal control and stop sign control, for these demand conditions? How should we proceed with this analysis?

We will first consider the operational performance of the intersection operating under today's control conditions (two-way stop-control) to confirm what we suspect: the high volumes on the main street (U.S. 95) will cause long delays on the side streets (Styner and Lauder Avenues). If this is found to be the case, it may further support a recommendation that signalization is a valid option to handle current and future traffic volumes. Even so, it is important to note that event-related conditions would not, by themselves, be sufficient justification for installing a traffic signal at this intersection.

We will then consider the operation of the intersection under signal control. Here, we will break down the analysis into four steps, one for each of the four time periods, in sequence, starting with the 4:00 p.m. to 4:15 p.m. time period.

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