The Institute of Transportation Engineers (ITE) Trip Generation Manual specifies a weekday PM peak hour trip generation rate for a single family home of 1.01 trips per unit, and 0.62 trips per unit for a multi-family dwelling unit such as a townhouse or a condominium. Since many of the communities (existing and proposed) within Lacombe contain a mixture of single and multi-family homes, Bunt & Associates expected to obtain and use a blended trip generation rate that was similar to the ITE rates (i.e. A blended rate greater than 0.62 and less than 1.01 trips per dwelling unit).
The data collected at the Northstar community by Bunt & Associates indicated a blended PM peak hour trip generation rate of 0.86 trips/unit. The area included 17% multi-family units, and so the rate of 0.86 trips per unit was felt to be reflective of a blended development. However, the 17% multi-family component present in that community was felt to be greater than what might be expected to develop in future residential communities, and so the rate was assessed to be low. A conservative rate of 1.0 trips per dwelling unit (including a mix of single and multi family homes) was therefore selected as the appropriate rate for the purpose of modeling to the 20,000 population horizon. This rate is slightly smaller than the 1.03 trips per dwelling unit rate utilized in the 1990 Transportation Study.