trip generation comparison ite land use and rate units am

Comments from W-Trans Regarding Condos versus Apartments September 30, 2015

The traffic study applied standard ITE rates for the “Residential Condominium” use. Using standard ITE rates for the “Apartments” land use, the projected trip generation would be slightly higher, at 49 a.m. peak hour trips and 60 p.m. peak hour trips (versus the 42 a.m. peak hour and 50 p.m. peak hour trips used in the traffic study). However, given the project’s density and three-story configuration, it is appropriate to apply the ITE trip generation rate for “Mid-Rise Apartment” instead. According to ITE, “Mid-rise apartments are apartments in rental buildings that have between three and 10 levels (floors).” Mid-rise apartments generate fewer trips per unit, which is consistent with land use/transportation research that has shown an inverse relationship between residential density and vehicular trip generation.

A comparison of the applied trip generation rates versus those that would be projected using “Mid-Rise Apartment” rates is shown below. The projected trip generation for the project using Mid-Rise Apartment rates is shown for both the average ITE rates as well as the 90th percentile ITE rates (which represent the 90th percentile highest trip generation rates among the actual sites used by ITE in developing the Mid-Rise rates).

Trip Generation Comparison

ITE Land Use and Rate Units AM Peak Hour PM Peak Hour

Rate Trips In Out Rate Trips In Out

Residential Condominium (applied in

TIS)

96 du 0.44 42 7 35 0.52 50 33 17

Mid-Rise Apartment (average rate) 96 du 0.30 29 9 20 0.39 37 22 15

Mid-Rise Apartment (90th percentile

rate)

96 du 0.39 37 12 25 0.49 47 27 20

Note: du = dwelling unit

As can be seen in the table, even if the trip generation for the proposed project was based on the 90th percentile highest ITE rates for Mid-Rise apartments, the resulting trip projections would still be slightly below those applied in the project’s traffic impact study. The transportation and circulation impacts identified in the traffic impact study are therefore considered to remain valid, if not slightly conservative.

ATTACHMENT 6H

City of Santa Rosa - Canyon Oaks Apartments Project Initial Study/Mitigated Negative Declaration

FirstCarbon Solutions H:\Client (PN-JN)\3316\33160005\ISMND\33160005 Canyon Oaks ISMND.doc

Appendix H: Traffic Study