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HomeMy WebLinkAboutPVH HEALTH SYSTEMS, HARMONY CAMPUS, 5TH FILING, HEALTHY LIVING CENTER - PDP - 32-98I - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORTVICINITY MAP SCALE: 1" = 1500' VICINITY MAP 12 McClellands Basin Drainage Master Planning concepts accepted by the City of Fort Collins. If groundwater is encountered at the time of construction, a Colorado Department of Health Construction Dewatering Permit will be required. C. Storm Water Quality Storm water quality will be addressed through the use of gravel inlet filters, erosion control fence, existing grass -lined detention ponds, and extended detention in Pond 593. D. Erosion Control Concept The proposed erosion control concepts will adequately provide for the control of wind and rainfall erosion from Poudre Valley Hospital. Through the construction of the proposed erosion control concepts, the City of Fort Collins performance standards will be met. REFERENCES Storm Drainage Design Criteria and Construction Standards by the City of Fort Collins, Colorado, May 1984, Revised January 1997. 2. Erosion Control Reference Manual for Construction Sites by the City of Fort Collins, Colorado, January 1991, Revised January 1997. 3. McClellands Basin 100-Year Master Plan Update, by Icon Inc., Fort Collins, 4. Final Drainage and Erosion Control Report Poudre Valley Health Systems Harmony Campus Infrastructure Project Development Plan, Fort Collins, Colorado, May 12, 2004. 10 V. STORM WATER QUALITY A. General Concept Storm Water Quality will be provided through extended detention, presently provided by existing Pond 593. This pond was constructed with PVH Filing 2. B. Specific Details Best Management Practices (BMP) for the treatment of storm water runoff will be provided through the use of gravel inlet filters, erosion control fence, and the existing grass -lined detention ponds 393 and 593. Furthermore, pond 593 will provide extended detention through its outlet structure. Erosion control fence shall be installed where shown in the final plans. Gravel inlet filters shall be installed for all storm drain inlets. Final calculations will be provided with the Final Drainage Report. VI. EROSION CONTROL A. General Concept At this time no erosion control calculations have been completed. These will be completed in Final Design. VII. CONCLUSIONS A. Compliance with Standards All computations within this report have been completed in compliance with the City of Fort Collins Storm Drainage Design Criteria. The City of Fort Collins Storm water Utility will not maintain the on -site storm drainage facilities within the Poudre Valley Hospital site. The owners of the Poudre Valley Hospital site will maintain their on -site storm drainage facilities on a regular basis. B. Drainage Concept The proposed drainage concepts presented in this study and those shown on the final I utility plans will adequately provide for the transmission of developed on -site runoff to the proposed detention ponds. The combination of on -site street capacities and the on -site storm sewer system will provide for the developed flows to reach the I proposed detention ponds. The sizes, locations and release rates of these ponds will allow the Poudre Valley Hospital site to develop in conformance with the I9 The runoff from the roof of the Healthy Living Center (basins 207 & 208) will be captured by a series of roof drains. The central and eastern portions of the roof (basin 207) will drain to the north and be conveyed east in the proposed storm drain in the landscaped area north of the building. This storm drain will also convey flows east into Swale A. The western portion of the roof (basin 208) will drain to the south and be released overland, south of the building. The runoff from basin 205 will flow overland towards a low point, located at the southeast corner of the parking lot. Here, the runoff will be conveyed east through a curb cut and into Swale A. Runoff from basin 206 will flow southeast down the private drive towards design point 206. Here, the flow will be released overland and will continue southeast and into Swale A. It is important to note that the existing 43" x 68" elliptical equalizer pipe between the existing north and south equalizer ponds (Pond 393 on PVH Filing 1 & 2 Plans) will be abandoned when the north pond is expanded and the south pond removed. Pond 393 will continue to serve primarily as a decorative retention/irrigation pond. The runoff from basins 50 and 51 of PVH Filing 2 will continue to be routed through Pond 393. The proposed storm drain upstream of basins 52 and 53 (PVH Filing 2) will be extended into Pond 393. The invert elevation of the extension will be set to control the water surface elevation, thereby passing runoff from basins 50 and 51 through Pond 393. The release will combine with that from basins 52 and 53 at the existing inlets in the private drive. The combined flow from basins 50-53 will continue to be routed south and east in the existing 24" storm drain. The existing 24" flared -end -section will be removed and proposed 24" storm drain added to allow connection into the proposed 54" RCP at design point 203A. Here, the flow from basins 50-53 of PVH Filing 2, will combine with that from PVH Filing 1 and basins 201-203 of PVH Filing 4, and continue east in the proposed 54" RCP. Ultimately, the runoff from basins 201-204 and those basins from PVH Filings 1 and 2 mentioned above, is conveyed east through the proposed storm drain, into Swale A, then south and east into Pond 593. Please refer to the PVHS Filing 2 Drainage and Erosion Control Report for more detailed information on basin 103, and Ponds 393 and 593. SWMM Model Please refer to the PVHS Filing 2 Drainage and Erosion Control Report. H. The storm flows from the Healthy Living Center Site will be conveyed to proposed area inlets, curb inlets, and a curb cut within the parking lot. The flows captured at ' these locations, will be conveyed east in the proposed storm drain line and released into the proposed swale (Swale A), east of the parking lot. Swale A will carry the flows south and into the existing swale, running south through basin 103 of the PVHS Master Infrastructure plans (see exhibit in Appendix Q. It is important to note that the southern equalizer pond (Pond 393) is not necessary. This means that the north equalizer pond will be reconfigured as a decorative pond for irrigation and to pass through storm flows. The stormwater from a portion of I Snow Mesa and Harmony Road (basins 50 and 51 of PVH Filing 2) will pass through the pond to design point 53. The flow will continue on to design point 203A, then into Swale A, and ultimately into Pond 593, located in the southeast corner of the PVH site. Furthermore, though the Healthy Living Center Site will increase impervious area within basin 103, upsizing is not required due to the SWMM Model from the PVHS Filing 2 Report, which provides a detention pond (Pond 593) in the Southeast corner of the PVH Site. The SWMM model provided for 80% imperviousness over the Ientire PVH Site. Water quality for the entire PVH site is provided for in Pond 593. It is important to note that Pond 593 is only partially constructed at this time. The current build -out of Pond 593 provides the required detention due to the development of the Healthy Living Center. The remaining portion of Pond 593 will be constructed along with future developments within the PVH Site. eB. Specific Details The Healthy Living Center Site contains approximately 9.24 acres. Runoff from the site will be routed east into Swale A. tA small western portion (basin 201) of the Healthy Living Center Site will flow west and will be captured by the existing 15' Type R Inlet (design point 201). The flow ' from basin 201 will join with flows from PVH Filing 1 (basins 1, 12, & 14-20) and flows from PVH Filing 2 (basins 50-53, & 104) and will conveyed east in the existing 43" x 68" elliptical storm drain. Meanwhile, runoff from basins 202-206 will be conveyed to its respective design point. A 5' Type R Inlet will capture runoff from basin 202, while area inlets will capture runoff for basins 203 and 204. Once captured, the flows from basins 202-204 combine with that from basin 201 and the above mentioned PVH Filing 1 and 2 basins, and are routed east in the existing and proposed storm drain, and into Swale ' A. VA III. DRAINAGE BASIN CRITERIA A. Regulations The City of Fort Collins Storm Drainage Design Criteria is being used for the subject site. B. Development Criteria Reference and Constraints I The criteria and constraints from The McClellands Basin 100-Year Master Plan and the subsequent update, dated March 2000 by Icon Engineering will be utilized in this Drainage Study. The Poudre Valley Hospital site is currently being utilized as ■ fallow agricultural land C. Hydrologic Criteria The SWMM hydrologic model that was previously used in the McClellands Basin 100-Year Master Plan Update by Icon Engineering has been utilized and updated in PVH Master Infrastructure report in order to analyze the hydrologic conditions of the proposed Healthy Living Center Site. Furthermore, rational calculations have been provided in Appendix B for the site, as well as curb cut and storm drain sizing using UDInlet and UDSewer. D. Hydraulic Criteria All calculations within this study have been prepared in accordance with the City of Fort Collins Storm Drainage Criteria and are included in the PVHS Filing 2 Report appendix. IV. DRAINAGE FACILITY DESIGN A. General Concept ■ The purpose of this report is to address the storm drainage flows from the I development of the Healthy Living Center Site, in relation to the Master Drainage Plan contained in the PVHS Filing 2 Drainage Report, May 12, 2004. I The Healthy Living Center Site is contained within basin 103 of the PVHS Filing 2 Report (see Drainage Exhibit in Appendix Q. The Healthy Living Center Site accounts for approximately 9.24 acres of the 22.26 acres in basin 103. I C PRELIMINARY DRAINAGE AND EROSION CONTROL REPORT FOR THE POUDRE VALLEY HEALTH SYSTEMS HEALTHY LIVING CENTER, FILING 4. FORT COLLINS, COLORADO I. GENERAL LOCATION AND DESCRIPTION A. Location The Poudre Valley Health Systems site is located south of Harmony Road and east of Timberline Road in southeastern Fort Collins, Colorado. The site is shown on the Vicinity Map in Appendix A. More particularly, the site is situated in the northwesterly portion of Section 5, Township 6 North, Range 68 West of the Sixth P.M., City of Fort Collins, Larimer County, Colorado. B. Description of Property The Healthy Living Center Site is located in the north portion of the PVH Site and accounts for approximately 9.24 acres of the 72.6 acres contained within the Poudre Valley Health Systems Harmony Campus Medical Center Filing 2. The Healthy Living Center Site currently consists of fallow farmland, a detention pond, and some landscaping on the west boundary. A private drive also extends along the north property line. The site generally slopes to the east at approximately 2.0%. II. DRAINAGE BASINS A. Major Basin Description The Healthy Living Center site lies entirely within the McClellands Basin. The project drainage is modeled in The McClellands Creek Master Drainage PlanUpdate (March 2000). Applicable portions of these studies are included in Appendix C, of the PVHS Harmony Campus Infrastructure Project Development Plan Drainage and Erosion Control Report, May 12, 2004. (See Major Basin Description in above Report) B. Sub -Basin Description (See PVHS Filing 2 Drainage Report) 5 APPENDIX PAGE VICINITY MAP A RATIONAL CALCULATIONS, CURB CUT & STORM DRAIN SIZING B DRAINAGE & EROSION CONTROL PLAN DRAWING C TABLE OF CONTENTS DESCRIPTION I. GENERAL LOCATION AND DESCRIPTION A. LOCATION B. DESCRIPTION OF PROPERTY H. DRAINAGE BASINS A. MAJOR BASIN DESCRIPTION B. SUB -BASIN DESCRIPTION III. DRAINAGE DESIGN CRITERIA A. REGULATIONS B. DEVELOPMENT CRITERIA REFERENCE AND CONSTRAINTS C. HYDROLOGICAL CRITERIA D. HYDRAULIC CRITERIA IV. DRAINAGE FACILITY DESIGN A. GENERAL CONCEPT B. SPECIFIC DETAILS V. STORM WATER QUALITY A. GENERAL CONCEPT B. SPECIFIC DETAILS VI. EROSION CONTROL A. GENERAL CONCEPT VII. CONCLUSIONS A. COMPLIANCE WITH STANDARDS B. DRAINAGE CONCEPT C. STORM WATER QUALITY D. EROSION CONTROL CONCEPT REFERENCES PAGE I 5 5 6 6 6 6 6 6 6 7 9 9 9 9 9 9 9 9 10 10 10 Stantec Consulting Inc 209 South Meldrum Street Fort Collins CO 80521-2603 Tel: (970) 482-5922 Fax: (970) 482-6368 stantm.com Stantec February 15" Mr. Basil Hamdan City of Fort Collins Water Utilities --Storm water 700 Wood Street Fort Collins, Colorado 80521 RE: Preliminary Drainage and Erosion Control Report for Poudre Valley Health Systems Harmony Campus Healthy Living Center, Filing 4. Dear Basil: We are pleased to submit to you, for your review and approval, this Preliminary Drainage and Erosion Control Report for Poudre Valley Health Systems Harmony Campus Healthy Living Center, Filing 4. All computations within this report have been completed in compliance with the City of Fort Collins Storm Drainage Design Criteria, and adhere to the Final Drainage and Erosion Control Report for the Poudre Valley Health Systems Harmony Campus Infrastructure Project Development Plan, Fort Collins, Colorado, May12, 2004. We appreciate your time and consideration in reviewing this submittal. Please call if you have any questions. Respectfully, Stantec Prepared by: John Gooch, EIT Jim Allen -Morley, P.E. Project Engineer Project Manager Preliminary Drainage and Erosion Control Rep ort ortt p Stantec Poudre Valley Health Systems Harmony Campus Healthy Living Center, Filing 4 Fort Collins, CO February 15, 2005 No Text