The URL can be used to link to this page

Home My WebLink AboutTACO BELL RESTAURANT - 51-90 - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORTDRAINAGE INVESTIGATION FOR PROPOSED TACO BELL RESTUARANT FORT COLLINS, COLORADO ARCHITECTURE ONE 150 East 29th Street Suite 200 Loveland, Colorado 80538 November 30,1990 Project No. GRD-040.90 PREPARED BY: Messner Engineering Associates 150 East 29th Street, Suite 225 Loveland, Colorado 80538 Telephone: (303) 663-2221 Civil and Environmental Engineering Consultants Drainage Summary for Proposed TACO BELL Restaurant to be located on Lots 7 thru 10, Block 6, R. C. MOORE'S SECOND ADDITION to the City of Fort Collins, Colorado Existing Conditions: Total Area = 0.703 ± acres Rational "C" factor = 0.755 Onsite Runoff. Q 2 = 1.33 c.f.s. Offsite Flows: Q 2 = 0 c.f s. Total Runoff: Q 2 =1.33 c.f.s. Developed Conditions: Total Area = 0.634 ± acres Rational "C" factor = 0.862 Onsite Runoff. Offsite Flows: Total Runoff: Detention Summary: Q 2=1.37c.f.s. Q 2 = 0 c.f.s. Q 2 =1.37 c.f.s. Qioo = 4.81 c.fs. Qioo = 0 c.f.s. Qioo = 4.81 c.f.s. Qioo = 4.95 c.f.s. Qioo = 0 c.f.s. Qioo = 4.95 c.f.s. On site detention facilities are not proposed. Site runoff to flow into the existing Storm Sewer located in Prospect Road adjacent to the site at its Southerly boundary. Drainage Basin Statistics: Gross Platted Area: 0.703 ± Acres Gross Area Rational "C" Factor: 0.87 Net Platted Area: 0.634± Acres Net Area Rational "C" Factor: 0.862 Onsite Detention: 0 c.f./ac. Basin: SPRING CREEK Engineering Associates November 30, 1990 Project No. GRD-040-90 Mr. Al Hauser, Architect ARCHITECTURE ONE 150 East 29th Street Suite 200 Loveland, Colorado 80538 Dear Mr. Hauser, The enclosed report represents the results of the drainage investigation for the proposed TACO BELL to be located on Lots 7 thru 10, Block 6 of the R. C. Moore's Second Addition to the City of Fort Collins, Larimer County, Colorado. This investigation was based upon the proposed site development plan and plat; proposed site grading plan; on -site observations; and available topographic information. The investigation was performed in accordance with the criteria established in the City of Fort Collins "Storm Drainage Design Criteria and Construction Specification Standards" manual. Thank you for the opportunity to be of service to you. If you should have any questions, please feel free to contact this office. es DRM/mkm Enclosures Civil & Environmental Engineering Consultants 150 East 29th Street, Suite 225 Loveland, Colorado 80538 Telephone: (303) 663-2221 TABLE OF CONTENTS Letter of Transmittal Table of Contents Scope Site Description Existing Conditions Proposed Development Conclusions and Recommendations ii 2 2 Vicinity Map Existing Conditions Exhibit Grading & Drainage Exhibit Calculations ii SCOPE The following report represents the results of a drainage investigation for a proposed TACO BELL restaurant to be located on a parcel of land situated in the Southwest Quarter of Section 13, Township 7 North, Range 69 West of the 6th P.M., Larimer County, Colorado. The site legal description is: Lots 7 thru 10, Block 6 of the R. C. Moore's Second Addition to the City of Fort Collins.The investigation was performed for 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 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 and plat; proposed site development construction 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 DESCRIPITION The site is rectangular in shape and contains approximately 0.703 acres. The site's East-West dimension is approximately 143 feet and its North -South dimension is approximately 213 feet. The site abuts the easterly right-of-way of College Avenue and the northerly right-of-way of Prospect Road. The site is located In the SPRING CREEK DRAINAGE BASIN. EXISTING CONDITIONS The site presently consists of two separate uses. A brick structure is located on the northern half of the site. This structure was originally constructed as a single-family residence but has been utilizied as an office building for the past several years. A TACO BELL restaurant is located on the southerly half of the site at the Northeast corner of the intersection of College Avenue and Prospect Road. The site slopes gently from North to South toward Prospect Road at a slope of approximately 3%. The site does not receive run-off from the properties to the North. The runoff generated on the adjacent property is directed westerly into the gutter of College Avenue or easterly into the alley. Runoff that enters both the gutter in College Avenue and the alley flows southerly to Prospect Road. A storm inlet that is located at the easterly end of the curb radius at the northeast corner of the intersection of College and Prospect intercepts flow from the north. Excess flow continues easterly along Prospect to Remington and then southerly along Remington to Spring Creek. PROPOSED DEVELOPMENT The proposed re -development of the site is to consist of the demolition of both the existing residential/office structure and the existing TACO BELL structure that are presently situated on the site. The construction of a new restaurant structure and the associated parking and drives will then take place. The sequence of demolition and construction may be such that the existing restaurant remain operating while the new structure is being constructed. 1 PROPOSED DEVELC IENT(cont.) Other improvements that will ultimately effect the grading and drainage for the site is the proposed reconstruction of the intersection of College and Prospect. This construction is being proposed in order to provide channelizing and turning lanes to improve traffic flow in the area. In order to do this the street will be widened. The future curb and gutter is to be moved back 4 ft. along College Avenue and 15.5 ft. along Prospect Road. This will also require that the storm drainage inlet located at the northeast corner of the intersection be reconstructed. The proposed grading and drainage plan for the site has taken this future construction into account. The perimeter grades have been established by continuing the crown slope grades of the existing roadways to the proposed gutter locations. CONCLUSIONS AND RECOMMENDATIONS 1. The proposed development will retain the existing drainage patterns. 2. The site is located in the SPRING CREEK DRAINAGE BASIN. The site is not located within the floodway or flood plain. 3. All development is to be performed in accordance with City of Fort Collins Standards and Specifications. Onsite detention of stormwater is not recommended due to the insignificant change in the site's drainage characteristics. 5. The City of Fort Collins Standards for temporary erosion control measures are to be incorporated with the construction activities. Specifically, a sediment trap is to be placed at the storm drain inlet. 2 _._VICINITYMA.P'_.r. I <Q 4/ SCALE: 1"-20' 4?1 P,/R- TIE1.0 10(9 OFF LtPE x LIME RTIE 040. 40 N' 143.51' FENCE 00 LIWE Cov�lF- c PF P.. /fol lve PHONE PEP co F7 30-6 41' BRICK a co zz,. W/ BA5F-M&AT 64A ViE 4- uN K GARAGE—" 5.8 0 3u,3.6 1530 S. COLLEGE FF. r.F.= 01 \!o 39 Otid'ol 40' 0� 0 L7,oe 11 V(;,�- 0 r-!,\ IJ /o Ani - 0, . BRICK 0 Z4" )< PGMP5TFA, cc) P, / R. 7t A,\U D. P-eTA101W6 WALL �' Q. -01 A,5PHAUI 01 0 0Z OA,�,c GAS 0 1 METER Ate' 5TOOE' wo &A5EME0 V (Q . . J A� Pj x u �:- TACO BELL �ESLAU�PtJT ::j tA,j F.F. ql.'I I OQ 414 slc3w J: Alp &VI co o" TRAFFIC 51GhIAL TRAFFIC StGWAL, 143 iz. GUTTER ".'cooc. CURB PUT CURB CUT A/ MA.0 �AOLC- FLOWL /-./,0 (-srd" //V PROSPECT ROAD co AM 1 EXISTING` CONDITIONS.--EXHI R.1 TA., Client: ARCHITECZ yE ONE Project No. GRD-040-90 By: DRM Date: Nov. 30, 1990 Calculations for Drainage Investigation for Lots 7 thru 10 , Block 6 of R. C. Moore's 2nd Addition located in the SW1/4 of Section 13, Township 7 North, Range 69 West of the 6th P.M., City of Fort Collins, Larimer County, Colorado Total Site Area = 0.703 ± acres of existing platted property The proposed development of the site is to consist of demolition of the existing structures on the site and the construction of a new TACO BELL restuarant. The site will be required to dedicate property along College Ave. and Prospect Road due to proposed street widening projects proposed to occur in the near future. The net area of the site after right-of-way dedication is anticipated to be: Net Site Area = 0.634 ± acres EXISTING CONDITIONS Rational "C" Factor = 0.20 for Lawns and Landscaped Areas It " " = 0.95 for Roofs, Decks, Patios, etc. 11 = 0.95 for Asphalt and Concrete Streets, Drives, and Parking It I = 0.50 for Gravel Streets, Drives, and Parking "C"avg (Existing) Lawns and Landscaped Areas = 3,728 sq.ft.± Roofs, Decks, Patios, etc. = 7,649 sq.ft.± Streets, Drives, and Parking = 12,196 sq.ft.± Gravel Drives, and Parking = 7,050 sq.ft.± Total Site = 30,623 sq.ft.± "C" avg = 1(3,728 x 0,20) + (7,649 x 0,95) + (12,196 x 0,95) + (7,050 x 0,50A 30,623 "C" avg = 0. 755 PROPOSED DEVELOPMENT "C"avg : Lawns and Landscaped Areas = 3,250 sq.ft.± Roofs, Decks, Patios, etc. = 2,520 sq.ft.± Streets, Drives, and Parking = 21,835 sq.ft.± Total Site = 27,605 sq.ft.± "C" avg = K3,250 x 0.20) + (2,520 x 0.95) + (21,835 x 0.95)) + 27,605 = 0.862 "C"avg = 0.862 Time of Concentration (Overland): T((min.) = 1.8 [ 1.1 - (Cf x C) ] 4L(ft.) + 34S(%) EXISTING CONDITIONS Tc 2 Year = 1.8 [ 1.1- (0.755 x 1.0) ] 480 + 342.9 = 3.75 min. Tc loo Year = 1.8 [ 1.1- (0.755 x 1.25) ] 480 + 342.9 = 1.70 min. Time of Concentration (Channel): T(min.) = L(ft.) + [Vel. (ft./sec.) x 60 min./sec.] T=300+[3x60]=1.67min. Page 1 of 2 Client: ARCHITECT E ONE Project No. GRD-040-90 By: DRM Date: Nov. 30, 1990 TTotal = Tc + T Therefore, T2 = 3.75 + 1.67 = 5.42 min. Tioo = 1.70 + 1.67 = 3.37 min. Both are less than the considered minimum of 10 minutes, therefore, use: 10 minutes as Time of Concentration. 12 @ 10 min. = 2.50 in./hr. RUNOFF Runoff, Q =CxIxAxCf Cf at 2 year Storm = 1.0 EXISTING CONDITIONS: Q2=0.755x0.703x2.5x1.0=1.33c.fs. Qioo = 0.755 x 0.703 x 7.25 x 1.25 = 4.81 c.£s. PROPOSED CONDITIONS Q2 = 0.862 x 0.634 x 2.5 x 1.0 =1.37 c.fs. Qioo=0.862x0.634x7.25x1.25=4.95cfs. Iioo Q 10 min. = 7.25 in./hr. Cfat 100 Year Storm = 1.25 The difference between the existing and proposed conditions is insignificant. The estimated difference in total runoff volume for the 2 Year and 100 Year Storms is 22 cu. ft. and 86 cu. ft. Therefore, onsite detention is not proposed. Page 2 of 2