The state transportation agency has established crash reduction factors shown in the table. An intersection has been identified as having an abnormally high left turn crash rate (17, 20, and 18 crashes in the last three years), attributed to excessive speeds and the absence of an exclusive left-turn phase. The ADT of the intersection for the last three years is 8,400, and the ADT for after implementation is 9,500. Determine (a) the appropriate countermeasures and (b) the expected reduction in crashes if the countermeasures are implemented.

The state transportation agency has established crash reduction factors shown in the table. An intersection has been identified as having an abnormally high left turn crash rate (17, 20, and 18 crashes in the last three years), attributed to excessive speeds and the absence of an exclusive left-turn phase. The ADT of the intersection for the last three years is 8,400, and the ADT for after implementation is 9,500. Determine (a) the appropriate countermeasures and (b) the expected reduction in crashes if the countermeasures are implemented.

Traffic and Highway Engineering

5th Edition

ISBN:9781305156241

Author:Garber, Nicholas J.

Publisher:Garber, Nicholas J.

Chapter5: Highway Safety

Section: Chapter Questions

Problem 23P

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