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HomeMy WebLinkAboutSite Certifications - 02/24/20227200 South Alton Way, Suite C400 Centennial, CO80112 303-740-9393  Fax 303-921-7320 130 East Kiowa Street, Suite 400 Colorado Springs, CO80903 719-593-2593  Fax 303-921-7320 2900 South College Avenue, Suite 3D Fort Collins, CO80525 970-491-9888  Fax 303-921-7320 MEMORANDUM JR Engineering, LLC has completed the attached Overall Site and Drainage Certification, including support exhibits, for the High Top Cultivation Facility (See attached Exhibit A - Vicinity Map). The following is a summary of the findings and determinations made while performing the site walk/inspection, review of the “As-Built Drawing” (attached as Exhibit B), and comparison of LID requirements (see Exhibit C – Impervious Area/LID Exhibit attached). It is important to note four things while reviewing this memo. First, the owner/contractor has been approved to delay the installation of re-vegetative seeding and the proposed grass buffer south of the parking area, until Spring, 2022; as installation is currently prohibited due to winter/frozen conditions. Second, this project has no new storm system, water quality or detention ponds proposed or constructed with the site for two reasons: 1. The overall property has been subdivided previously into 3 lots. Kind Care dispensary is already improved and located on Lot 1. This project, High Tops Cultivation Facility is now constructed and located on Lot 2. Lot 3 contains the water quality and detention ponds for all three lots, and was found to be adequate for the improvements on Lot 2, as previously constructed. And 2. The entire property is very flat, with no subterranean storm outfall (Lot 3 detention/water quality pond drains to the western flowline of College Avenue. Thus, the far west part of the overall property flows overland to the southeast (Lot 3) and the natural overland drainage swales have not been altered by this project, since they are currently draining positively and sufficiently. Third, this project constructed the concrete paved emergency access turn around alley, which was proposed by the Kind Care project, but never installed. This added imperviousness was already taken into account in the drainage report for that project. Lastly, this project’s improvements are mainly resurfaced paved area grading to improve the fall around the structure. The finished floor elevations are fixed for this facility and thus, natural grades/swales on the north, west and south open areas have been preserved. Conclusion: The High Tops As-Built conditions are in general compliance with the approved Final Drainage Memo “High Top Cultivation Facility – Weighted Impervious Drainage Analysis” (attached as Exhibit F), Dated January 6th, 2021, Final Drainage Report for High Top Cultivation Facility circa June, 2021 and approved final grading plan. The project is constructed to provide adequate storm drainage for the 100-year storm event. The following Stipulations/Clarifications to this memo apply (marked as “No”), based on the City’s completed “Overall Site and Drainage Certification” that follows: II. Channels/Swales – FCSCM Ch.8, Sec. 2.0 and Ch9, Sec. 5.0 2. “No” – There were no changes in swale slope to native open space/yard areas south, west and existing grading north of the structure. As noted in the narrative above, slopes from the west side of Lot 2 are To:Mr. Wes Lamarque, PE From: Tim Halopoff, PE, CFM Date:February 11, 2022 Subject:High Top Cultivation Facility – Overall Site & Drainage Certification Wes Lamarque 2/24/2022 7200 South Alton Way, Suite C400 Centennial, CO80112 303-740-9393  Fax 303-921-7320 130 East Kiowa Street, Suite 400 Colorado Springs, CO80903 719-593-2593  Fax 303-921-7320 2900 South College Avenue, Suite 3D Fort Collins, CO80525 970-491-9888  Fax 303-921-7320 existing and fixed, due to the existing structure finished floors, the shallow nature of the detention pond, and no ultimate subterranean storm system outfall (overall site drains to College Avenue curb line). The existing swale conditions are less than 2% fall, but operate with adequate drainage for the existing structure and lot. XIII. Certification of LID and Water Quality Facilities – FCSCM Ch.7 A.“No” – As stated in Narrative above, the owner/contractor has been approved to delay the installation of the only proposed LID measure “Grass Buffer” in Spring, 2022. The checklist and pictures/documentation will be performed at that the future time of installation. D.“No” – As stated in Narrative above, the owner/contractor has been approved to delay the installation of the only proposed LID measure “Grass Buffer” in Spring, 2022. The visual verification of the LID feature will be performed at time of construction. Respectfully, Tim Halopoff, PE, CFM 970.817.1010 High Tops BDR 2/11/2022 82009154 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A Yes N/A No Yes Yes Yes Yes N/A N/A N/A N/A Yes Yes Yes Yes N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A Yes Yes Yes Yes N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A Yes Yes Yes Yes Yes Yes Yes Yes N/A N/A N/A N/A N/A Yes Yes Yes N/A No N/A N/A No A Westrian Company SITE C- 3 2 5 3 9 C-3 2539 N/A N/A N/A On behalf of DocuSign Envelope ID: 5DACE0F8-5E80-49CC-B0F6-C1FC2BCDBC93 1/28/2021 1/28/2021 1/29/2021 Th i s u n o f f i c i a l c o p y w a s d o w n l o a d e d o n J a n - 1 0 - 2 0 2 0 f r o m t h e C i t y o f F o r t C o l l i n s P u b l i c R e c o r d s W e b s i t e : h t t p : / / c i t y d o c s . f c g o v . c o m Exhibit C - Original Site Drainage Plan Th i s u n o f f i c i a l c o p y w a s d o w n l o a d e d o n J a n - 1 0 - 2 0 2 0 f r o m t h e C i t y o f F o r t C o l l i n s P u b l i c R e c o r d s W e b s i t e : h t t p : / / c i t y d o c s . f c g o v . c o m Fo r a d d i t i o n a l i n f o r m a t i o n o r a n o f f i c i a l c o p y , p l e a s e c o n t a c t C i t y o f F o r t C o l l i n s U t i l i t i e s 7 0 0 W o o d S t r e e t F o r t C o l l i n s , C O 8 0 5 2 4 U S A HIGH TOP CULTIVATION FACILITY BASIC DEVELOPMENT REVIEW VICINITY MAP NTS LOT 2 OF DINGS SUBDIVISION, 6629 S. COLLEGE AVE., FORT COLLINS, COLORADO 80525 LEGEND A W e s t r i a n C o m p a n y HI G H T O P C U L T I V A T I O N F A C I L I T Y BA S I C D E V E L O P M E N T R E V I E W IM P E R V I O U S A R E A E X H I B I T SITE X: \ 3 9 7 0 0 0 0 . a l l \ 3 9 7 8 3 0 0 \ D r a w i n g s \ P r e s e n t a t i o n s \ 3 9 7 8 3 0 0 I m p e r v i o u s E x h i b i t . d w g , B D R S i t e P l a n , 6 / 1 2 / 2 0 2 0 9 : 3 2 : 1 5 A M , F C Exhibit D - Proposed Impervious/Water Quality Areas 7200 South Alton Way, Suite C400 Centennial, CO80112 303-740-9393  Fax 303-921-7320 130 East Kiowa Street, Suite 400 Colorado Springs, CO80903 719-593-2593  Fax 303-921-7320 2900 South College Avenue, Suite 3D Fort Collins, CO80525 970-491-9888  Fax 303-921-7320 MEMORANDUM JR Engineering, LLC has completed a weighted imperviousness based storm drainage evaluation for the High Top Cultivation Facility. The following is a summary of the findings and determinations made while performing an analysis of the proposed emergency access paving addition, concrete mechanical pad, and sidewalk. It is important to note three things while reviewing this memo. First, we believe that this project will not be required to provide a full drainage report, water quality or detention facilities, based on the proposed site condition having a net reduction in impervious area from the sites existing condition. Second, this analysis has been performed using a “weighted impervious area” calculation, which is the square footage of each impervious surface type, multiplied by the surfaces weighted impervious coefficient values for infiltration characteristics of different materials (< 1). The impervious coefficient values were derived from the City of Fort Collins Stormwater Criteria Manual Table 4.1-3 “Surface type – Percent Impervious”. Lastly, the High Top Cultivation Facility site area’s drainage pattern was originally included in the “Stormwater & Erosion Control Report for Kindcare” prepared by Forbes Engineering and approved by the City of Fort Collins September 26, 2016. The “Proposed Impervious Area Exhibit” and “Proposed Drainage Sub- Basins” maps from the original report can be referenced in Appendix C. The High Top Cultivation Facility project site is located along the west side of South College Avenue and south of West Trilby Road as seen on the vicinity map in Appendix A. The property currently supports an existing metal building, which covers an approximate footprint of 18,270 sf. Just south of the building lies an existing asphalt parking area and a vacant earth/gravel area to the west. The site is composed primarily of type C soils and generally, slopes from 0 to 2 percent towards the lot’s eastern property line. A specific breakdown of weighted impervious areas that compares existing areas to proposed improvement areas can be found on the “Impervious Area Exhibit” within Appendix C. All flows generated in the existing condition can be found in the “Stormwater & Erosion Control Report for Kindcare” as previously mentioned. The proposed improvements will include the addition of 5,578 sf of concrete/asphalt area and the removal of 842 sf of existing asphalt for landscape planters. The proposed improvements are composed of the addition of 2,390 sf of asphalt surface for emergency access, replacing a portion of existing parking with landscape planters and sidewalk, the addition of 869 sf concrete mechanical pad, 2,319sf of sidewalk, and removal of the on-site gravel area to be replaced with seed and landscaping. To:Mr. Wes Lamarque, PE From:Tim Halopoff, PE, CFM Date:Jan 6, 2021 Subject:High Top Cultivation Facility – Weighted Impervious Drainage Analysis Exhibit F - Imperviousness Memo