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HomeMy WebLinkAboutBLOOM FILING ONE - PDP210014 - SUBMITTAL DOCUMENTS - ROUND 6 - VARIANCE REQUEST (3) 5265 Ronald Reagan Blvd., Suite 210 Johnstown, CO 80534 970.800.3300 • GallowayUS.com July 13, 2022 City of Fort Collins Engineering Department 281 North College Avenue Fort Collins, CO 80522 RE: Bloom Filing One – Greenfields Drive Curve and Tangent Variance Request Dear Dave Betley, Galloway, on behalf of Hartford Homes and in support of the Bloom project currently under review, is providing the following written justification for the curve radius and tangent length along Greenfields Drive, per the request of the City of Fort Collins. A) Identification of the standard to be waived or varied and why the standard is unfeasible or is not in the public interest. A variance is requested for the proposed curve radius and tangent length along Greenfields Drive as submitted in drawings dated 06/01/2022, shown on drawing C9.5- C9.11. Per chapter 7 of the LCUASS standards, The City of Fort Collins typically requires a 1075’ minimum centerline radius and a minimum tangent length of 200’ for a 2 lane arterial. However, due to site specific, spatial restraints a 1075’ centerline radius and 200’ tangent length is not feasible. These constraints are that Greenfields follows a shared property line to the south setting the southern alignment. To the north, the alignment is set perpendicular to the existing Vine Drive and aligned with the road on the north side of Vine Drive. These two constraints along with the need to intersect the railroad track perpendicularly necessitate the reduced radius and tangent length which coincide with 1 road classification lower (Major Collector). As such, a variance is being requested from 1075’ radii to 600’ radii and 200’ tangent length to 50’ tangent length. B) Proposing Alternate Design. Identification of the proposed alternative design or construction criteria. Along Greenfields Drive a variance is being requested to allow a 600’ centerline curve radius and a minimum 50’ tangent length. Which corresponds to the Major Collector design criteria (one road classification lower than a two lane arterial). Posted speed for a two land arterial and a major collector have overlap between 30-35 mph so posted speed would not exceed that of the lower road class criteria being varied to. C) A thorough description of the variance request including impact on capital and maintenance requirements, costs, and how the new design compares to the standard. Hartford Homes Bloom – Filing one July 13, 2022 Galloway & Company, Inc. Page 2 of 3 The City of Fort Collins requires a 1075’ centerline radius and 200’ minimum tangent length for a roadway of Greenfields Drive classification. The variance would have this road built with 600’ centerline radii and a minimum 50’ tangent length and essentially use the LUCASS standard for a Major collector. The site constraints make the 600’ radius curve the largest possible for this section of roadway. Specifically, the need to intersect the railroad perpendicularly as well as maintain the north and south tie in points necessitate the reduced radii and tangent length. Using 600’ radii curves allows Greenfields Drive to meet the controlling constraint as well as tie into intersecting roadways at the desired locations. In addition, the use of mitigation measures would allow this roadway to function safely for the public. These mitigation measures would be as follows: • Proper signage denoting a 30 mph speed limit (30 mph is a standard posted speed for both a 2 lane arterial and a major collector with 600’ radii per table 7-3 of LCUASS) • Proper signage denoting caution for a reverse curve in the roadway • Proper signage for the railroad crossing as coordinated with the city and rail authority. Through the use of the above mitigation measures this roadway would function safely for the public with the proposed design (as varied). Furthermore, varying the radius and tangent length to 600’ and 50’ would have no impact on maintenance or cost as the roadway would still be constructed using common radii and tangent lengths. D) Justification. The Professional Engineer must determine and state that the variance will not be detrimental to the public health, safety and welfare, will not reduce design life of the improvement nor cause the Local Entity additional maintenance costs. The proposed plan (as varied) must advance the public purpose of the standard sought to be varied equally well or better than would compliance with such standard. The proposed variance allows Greenfields Drive to function within the spatial restraints of the southern property line restriction, northern existing road tie in location and perpendicular rail crossing. The change to a commonly used radius (the radii of a Major Collector) will cause no impact to maintenance costs. And using the above mentioned mitigation measures would allow the roadway to function safely meaning the variance will have no impact to public health, safety and welfare. Sincerely, GALLOWAY Hartford Homes Bloom – Filing one July 13, 2022 Galloway & Company, Inc. Page 3 of 3 James Prelog, PE Civil Engineering Project Manager JamesPrelog@GallowayUS.com