HomeMy WebLinkAboutASCENT STUDIO CLIMBING & FITNESS - MAJOR AMENDMENT - MJA140003 - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORT105 South Sunset Street, Suite H | P.O. Box 1348 | Longmont, CO 80502
303.532.2268 | toddb@tjbconsulting.com
Civil Engineering | Site Design | Project Management
Infrastructure Design | Construction Assistance
July 31, 2014
City of Fort Collins
Community Development and
Neighborhood Services
281 N. College Avenue
PO Box 580
Ft. Collins, CO 80522
Re: Timberline Center
Drainage & Erosion Control Reports/Plan
Amendment for revised lots 12 and 13
Ascent Climbing Studios Building
To Whom it may concern:
We are preparing the letter associated with the site plan amendments for Lots 12 & 13 within the
Timberline Center:
Site Imperviousness:
Per the concept review letter dated November 22, 2013, we have calculated a comparison of the proposed
impervious area with the original assumed impervious area in the original approved plans and reports.
The new lot covers 62,120 square feet of the original plan. Within that areas, we calculated:
• 12,835 SF of building roof
• 39,164 SF of parking, walks, and other hardscape
• 10,212 SF of landscaped area
The new plan provides:
• 14,875 SF of building roof.
• 31,264 SF of parking, walk, and other hardscape
• 15,981 SF of landscaped area
Therefore, as the new layout provides additional landscape area than assumed with the original approvals,
the amended site plan for Ascent studios remains in compliance with the approved master drainage &
erosion control plans & reports originally prepared for the overall site.
Drainage Basin Compliance:
Site grading for the amendment site was prepared to strictly comply with the basin boundaries and areas as
presented in the originally approved plans. Sub-basins of the original basins are depicted within the
separate utility plan submittal, and grading high points were set based on the original locations of high
points the approved site grading plans.
Page 2 of 2
7/31/2014
Ascent Studios
TJB Consulting Group
LID Standards:
The City's new standards require, in general:
• 25% of the on-site paved area be porous pavement
• 50% of the new impervious area drain across the porous pavement.
We have calculated:
• The total parking area to be paved is 28,092 SF
• 25% of the total is 7,023 SF.
• The proposed site has been analyzed and found to provide 7,140 SF of porous pavement, as
presented within the constructions plans.
• The total impervious area created by this project is 46,139 SF.
• 50% of the total is 23,070 SF.
• By the placement of the porous pavement, coupled with the proposed roof pitch plan, we have
found that 34,580 SF of the impervious site will drain across the porous pavement.
Very Truly Yours,
TJB Consulting Group
Todd J. Borger, P.E 32993
F:\TJBcg\RBB Ascent Studios\Drainage\Timeberline Center Amendment Lots 12 13.doc