HomeMy WebLinkAboutVarianceRequest_RoadGrade_07262021
109 E Main Street, Ste B, Bozeman, MT 59715 I OFFICE 406.728.4611 I EMAIL wgm@wgmgroup.com
July 26, 2021
City of Bozeman
Engineering Department
20 East Olive Street
Bozeman, MT 59718
RE: Variance Request – City of Bozeman Design Standards and Specifications Policy
Section IV. E.1. Permissible Roadway Grades
Dear City of Bozeman:
The above referenced section of the City of Bozeman DSSP states: The minimum allowable grade for
any roadway or alley is one-half (0.5 percent). The maximum allowable grade for any roadway is
shown in Table IV-2 of this Policy. The maximum grade for an alley is subject to the approval of the
City Engineer.
The applicant is requesting a variance to this standard as it related to the creation of Roger’s Way in
Annie Subdivision Phase 4.
The applicant is requesting that the road grade of the new road connecting Rogers Way and Daffodil
Street be 0.43%. This grade accommodates a constant (i.e. straight-grade) for the new road section,
sloping from the Daffodil tie-in location to the Rogers Way tie-in location. The constant road grade
creates a smooth driving experience and allows stormwater to be routed to one location. This road
alignment is shown on the RoadPlanProfile exhibit.
The variance will not be contrary to and will serve the public interest. The design accommodates a
smooth, natural driving experience between the two existing roadways. The design also
accommodates a natural, efficient stormwater design. One alternative, which was proposed
previously, is to slope a small portion of the new roadway to the west (to Daffodil) and a portion of the
road to the north (to Rogers Way). A vertical curve would separate two drainage basins. The portion
of the road which slopes to the west (to Daffodil) would be small (around 100 lineal feet of roadway).
This area would require stormwater facilities (i.e. a detention pond) located in common open space.
Therefore, a common open space lot would be required on the west side of the project site. This
common open space lot would eliminate 1 or more of the proposed residential units, thus lowering the
amount of residential housing available from this development. This alternative would also require
two stormwater manhole structures located within the right-of-way to direct water to the pond.
Therefore, the granting of this variance would avoid an unnecessary hardship to the project.
In summary, this variance (0.43% road grade compared to 0.5% minimum per the DSSP) is sensible
from a planning and engineering perspective and does not negatively impact the development.
City of Bozeman Planning Department
July 26, 2021
Page 2 of 2
Sincerely,
WGM Group, Inc.
Gary Fox
PROJECT ENGINEER
W:\Projects\201016\Docs\Subdivision Submittal\Preliminary Plat Submittal\Response to DRC Comments - July 2021\VarianceRequest_RoadGrade_07262021.docx