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HomeMy WebLinkAboutLINCOLN EAST CONVENIENCE CENTER PUD, LOT 2 - FINAL - 40-94F - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORTVICINTY MAP (Not -to -Scale) VINE DR. BUCKINGHAN. ST. < SITE LINCOLN AVE. i i :E J iz ULBERRY ST. _� HIGHWAY t� VICINTY MAP fbr JERRY'S QUICK LUBE Property Description: Lot 1 of'Lincoln East - P.U.D., Second Filing" Fort Collins, Colorado 0 - T C-A- Q1 rl September 22, 1997 Project No. GRD - 245 - 97 Mr. Basil Hamdan Stormwater Utility City of Fort Collins 235 Mathews P. O. Box 580 Fort Collins, Colorado 80522 - 0580 Re: Lincoln East - P.U.D. Second Filing, Fort Collins, Colorado Dear Mr. Hamdan, The estimated cost for erosion control devices for the subject site has been estimated to be: 1. Silt Fence 37011 ® $2.00/ft. = $680.00 2. Straw Bale Filter 3 Each ® $75.00/Ea. $225.00 Total $905.00 Cost Q 150% = 1.5 x $905.00 = $1,537.50 The cost to re -seed the 37,464 square foot site at $0.0298/sq.ft. = $1,116.43 150% of the re -seeding cost = 1.5 x'$1,116.43 = $1,674.65 Therefore, the subject project's estimated erosion control security amount is determined to be $1,674.65. This amount is to be included as surety for the erosion control guarantee along with any other surety requirements that may be a part of the City's "Developer's Agreement" requirements. If you should have any questions or desire additional information, please feel free to contact this office. y Submitted, Engineering Associates AW: Dennis R. Messner, P.E. cc: Architecture One Civil and Environmental Engineering Consultants 150 E. 29th Street, Suite 238 Loveland, Colorado 80538 Telephone: (970) 663-2221 STORM WATER DETENTION SUMMARY SITE DRAINS TO "DRY CREEK" DRAINAGE BASIN GROSS SITE AREA (includes 1/2 of N. Lemay Ave.) = 51,200 Sq. Ft. = 1.175 Ac. ± NET SITE AREA = 37,464 Sq.Ft. = 0.86 Ac. ± HISTORIC "C" = 0.24 DEVELOPED "C" = 0.81 HISTORIC "Q2" = 0.34 c.f.s. CRITERIA BASED DETENTION VOLUME = 4,989 Cu.Ft. ± PLAN DETENTION VOLUME = 5,269 Cu.Ft. MAXIMUM DEPTH OF DETAINED WATER.= 5.25 feet Q High Water Elevation 4940 PEAK DISCHARGE FROM DETENTION, Q = 0.39 c.f.s. IREFERENCES 1. City of Fort Collins, STORM DRAINAGE DESIGN CRITERIA AND CONSTRUCTION STANDARDS, May 1984 with subsequent revisions and additions. 2. Preliminary Drainage and Erosion Control Study for Diamond Shamrock, Inc., Lincoln East P.U.D. at North Lemay Avenue & East Lincoln Avenue, Fort ` Collins, Colorado, prepared by Galloway, Romero & Associates, Englewood, n Colorado, February 1997. 3. Final Drainage and .Erosion Control Study for Diamond Shamrock, Inc., Lincoln East P.U.D. at North Lemay Avenue & East Lincoln Avenue, Fort Collins, Colorado, prepared by Galloway, Romero & Associates, Englewood, Colorado, April 1997. n The recommended short term erosion control methods to be incorporated with the " construction activities consist of the following: prior to commencing construction a "Silt Fence" is to be placed along the northern eastern boundary of the site in order to control and contain mud and debris onsite; upon completion of grading, operations and at the time that the drainage inlets are installed a "Straw Bale Filter" is to be placed at each inlet; and tracked mud to be cleaned up as required. Wind erosion measures are to consist of water application and roughening of exposed surfaces. CONCLUSIONS AND RECOMMENDATIONS 1. The proposed development will retain the "historic" drainage patterns. 2. The site is located in the DRY CREEK DRAINAGE BASIN. The site is located within a defined flood plain. A Permit to allow construction within the designated Flood Plain is to be required. 3. All development is to be performed in accordance with City of Fort Collins criteria. A variance to the City's policies is requested from detention of adjacent street flows due to physical impracticality. 4. Onsite detention of storm water is required by the City of Fort Collins. The volume of run-off to be detained is estimated to be 4,989 cu. ft. The detention volume has been determined based upon the calculated volume of run-off generated by a 100 Year Storm. The entire site and one-half of the adjacent North Lemay Avenue have been considered as the tributary area to determine the volume of the detention pond. The volume generated from the tributary area is to be released at a controlled rate determined by the `historic' rate of run-off from the site for a 2 Year Storm. The calculated release rate is 0.34 c.f.s. 5. The City of Fort Collins Standards for temporary erosion control measures are to be incorporated with the construction activities. Specifically, the following are to be incorporated in the site construction activities: a. A "Silt Fence" is to be placed along the northern and easterly border of the �I site. b. "Straw Bale Filters" are to be placed at each inlet. C. Water application is to be made to prevent dust during the site development phase of the project. d. Roughening of the exposed earth surfaces shall take place during the site development phase of the project. 3 The area to the North is vacant land that is proposed for development by the City's Housing Authority. A small area to the North contributes to the drainage on site. The area to the East is vacant. D PROPOSED DEVELOPMENT 1i The proposed development is to consist of an 2,100 square foot commercial structure to �J be located in the east central portion of the site. The proposed access drives and nn parking are to be situated along the West, North, South and East sides of the structure. IJ As previously stated the run-off from the site currently flows toward the Southeast. The proposed site grading and drainage plan is designed to direct all of the run-off from the n site to an on site drainage system. The drains will discharge into a detention basin that 'J will release the run-off at a controlled rate to the proposed storm drain at the eastern side of the site. The City policies require that the difference between the historic rate of run-off and the developed rate of run-off be detained onsite. The release rate is to be no greater than the D 2 Year Storm historic rate. The preliminary drainage plan and report for "Lincoln East P.U.D." has established the detention requirement for the site at the difference between the "historic" run-off rate of 0.34 c.f.s. and the 100 Year storm event with the site considered fully developed. The proposed detention facilities will outfall to the 30" storm drain located along College Avenue. The City's policies normally require that the adjacent street flows be incorporated with the onsite detention requirements. This policy applies most efficiently when the street construction and onsite detention are performed concurrently. In this instance, it is physically feasible to direct the flow from North Lemay Avenue into the drainage system on site. The future improvements to North Lemay avenue may negate this effect. EROSION CONTROL MEASURES Erosion control considerations are based upon the short term activities that occur during construction and the long term measures that are to be placed for the life of the facility. The long term measures are the proposed methods and materials to be used,to provide surface treatments for the driveways, parking areas, walkways and the landscape materials and plantings in the open areas that will provide a combination of ground covers to deter erosion. The anticipated construction schedule should have the site grading completed, within one (1) week after commencing construction. The schedule for construction activities is anticipated to be: November 1 - November 7, perform site grading; November 7 - November 14, construct drainage related facilities; November 15 - November 21, install building foundation and water and sewer service lines; November 22 - January 30, construct structure; December 15 - December 21, construct curb, gutter and sidewalks; March 28 - April 1, place pavement; March 15 - March 25 install landscaping. 2 SCOPE The following report represents the results of a drainage investigation for a proposed commercial development to be located in the Northwest Quarter of Section 32, Township 7 North, Range 68 West of the 6th P.M.in the City of Fort Collins, Larimer County, Colorado. The investigation was performed for the project architect, Architecture One. The purpose of this investigation is to determine the effects of the proposed development on the area's existing drainage conditions and to determine the improvements, if any, and the appropriate sizing for the proposed improvements so that it may be incorporated with the construction of the project. The conclusions and recommendations presented in this report are based upon the proposed site development plan; proposed building plans; on -site observations; and the available topographic information. The analysis was performed in accordance with the City of Fort Collins "Storm Drainage Design Criteria and Construction Standards" manual. SITE DESCRIPTION The site is considered to be somewhat rectangular and contains approximately 1.02 acres. The site's East-West dimension is approximately 220 feet, its North -South dimension at the West boundary is approximately 200 feet and its North -South dimension at the East boundary is approximately 150 feet. The site abuts the easterly right-of-way of North Lemay Avenue. The site is located in the DRY CREEK DRAINAGE BASIN. "HISTORIC" CONDITIONS The site and the area to the South that is proposed as the 1st Filing of Lincoln East P.U.D. is presently two single family residences with outbuildings and associated agricultural uses. The ground surface varies from gravel driveways to moderate stands of vegetation. The site slopes are considered to be flat and range from 0 % to 1 %. The "historic" direction that the site slopes is from Northwest to Southeast toward East Lincoln Avenue. The run-off generated in the area to the West of North Lemay Avenue is directed into a 12 inch diameter culvert that is situated along the westerly side of North Lemay Avenue. The culvert discharges borrow ditch at the northerly side of East Lincoln Avenue. The area to the South of the site is the Lincoln East P.U.D. First Filing and is proposed for a Diamond shamrock convenience center. The site improvements for the Diamond Shamrock have been designed to to direct the surface run-off to a detention basin located at the South side of the site. No run-off from the South contributes to the drainage on site and in fact the Diamond Shamrock site will accept and detain the southern half of the common access drive between the sites. The area to the West of North Lemay Avenue has been developed to drain to the borrow ditch along the western side of Lemay Avenue. The run-off generated to the West flows to the South away from the site. The easterly limit of the Cache La Poudre River Floodway is situated along the easterly right-of-way of North Lemay Avenue. The site is situated in the flood fringe area, Zone A-4 as designated on the Flood Insurance Rate Map Community Panel No. 080101-0179 C, dated: March 18, 1996. 1 TABLE OF CONTENTS Letter of Transmittal Table of Contents Scope Site Description "Historic" Conditions Proposed Development Erosion Control Measures Conclusions and Recommendations References Drainage Summary Erosion Control Cost Estimate letter i ii 1 1 1 2 2 3 4 EXHIBITS Vicinity Map Proposed Conditions Exhibit Calculations ii t I I Mr. Basil Y. Hamdan Stormwater Utility 235 Mathews P. O. Box 580 Fort Collins, Colorado 80522-0580 September 22, 1997 Project No. GRD - 245 - 97 Dear Mr. Hamdan, The enclosed report represents the results of the drainage investigation for the proposed "Jerry's Quick Lube" to be located on Lot 1 of "Lincoln East P.U.D. Second Filing" in the City of Fort Collins, Larimer County, Colorado. This investigation was based upon the proposed site development plan; proposed site grading plan; on -site observations; and available topographic information. The 1 investigation was performed in accordance with the criteria established in the City of Fort Collins "Storm Drainage Design Criteria and Construction Specification Standards" manual. tIf you should have any questions, please feel free to contact this office. Respectfully Submitted, ' MESSNEI n neering Associates ' Dennis R. Messner, P.E. DRM/mkm Enclosures . cc: Architecture One Civil and Environmental Engineering Consultants 150 E. 29th Street, Suite 238 Loveland, Colorado 80538 Telephone: (970) 663-2221 DRAINAGE INVESTIGATION FOR JERKY'S QUICK LUBE Lot 1 of the Lincoln East - P.U.D. 2nd Filing CITY OF FORT COLLINS, LAREVIER COUNTY, COLORADO Prepared for Architecture One 150 E. 29th Street Suite #200 Loveland, Colorado 80538 September 1997 Project No. GRD - 245 - 97 MMM� MRR EngineeHng Associates 150 E. 29th Street, #238 Loveland, Colorado 80538 alephone: (970) 663 - 2221