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HomeMy WebLinkAboutDrainage Reports - 02/01/1994W 116 Final ROPOO zi 1154-- PRELIMINARY/FINAL AND EROSION CONTROL STUDY KENNY ROGERS ROASTERS FORT COLLINS, COLORADO 1 1 1 1 PRELIMINARY/FINAL DRAINAGE AND EROSION CONTROL STUDY FOR KENNY ROGERS ROASTERS FORT COLLINS, COLORADO January 12, 1994 Prepared for: Client: Curtis Zook Kenny Rogers Roasters 11091 North Wolff Way Westminster, Colorado 80030 Prepared by: RBD, Inc. Engineering Consultants 209 South Meldrum Fort Collins, Colorado 80521 (303) 482-5922 RBD Job No. 563-002 %0INC. Engineering Consultants 209 S. Meldrum Fort Collins, Colorado 80521 303/482-5922 ' FAX: 303/482-6368 ' January 12, 1994 ' Mr. Glen Schleuter City of Fort Collins ' Utility Services Stormwater 235 Mathews Fort Collins, Colorado 80522 tRE: Preliminary/Final Drainage and Erosion Control Study for Kenny Rogers Roasters ' Dear Glen: We are pleased to submit to you, for your review and approval, this Preliminary/Final ' Drainage and Erosion Control Study for Kenny Rogers Roasters. All computations within this report have been completed in compliance with the City of Fort Collins Storm Drainage Design Criteria. Please note that a change was made to the plan per our ' discussion on erosion control. We appreciate your time and consideration in reviewing this submittal. Please call if you have any questions. Respectfully, ' BD Inc. Engineering Consultants ' Ter P. MCF�ar�y tStan A. Myers, P.E. 1 1 Other Offices: Denver 303/458-5526 • Vail 303/476-6340 TABLE OF. CONTENTS DESCRIPTION PAGE I. GENERAL LOCATION AND DESCRIPTION A. LOCATION B. DESCRIPTION OF PROPERTY II. DRAINAGE BASINS A. MAJOR BASIN DESCRIPTION B. SUB -BASIN DESCRIPTION DRAINAGE DESIGN CRITERIA A. REGULATIONS B. DEVELOPMENT CRITERIA REFERENCE AND CONSTRAINTS C. HYDROLOGICAL CRITERIA D. HYDRAULIC CRITERIA E. VARIANCES FROM 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 APPENDIX A VICINITY MAPS Al HYDROLOGY A2 EROSION CONTROL 1 1 1 2 2 2 2 2 3 3 3 4 5 5 5 5 I 1 PRELIMINARY/FINAL DRAINAGE AND EROSION CONTROL STUDY ' FOR KENNY ROGERS ROASTERS FORT COLLINS, COLORADO 1 I. GENERAL LOCATION AND DESCRIPTION 1 A. Location The proposed restaurant Kenney Rogers Roasters is to be located at the southeast corner of East Monroe Avenue and South College Avenue in the commercial shopping mall, 'The Square". The site is shown on a Vicinity Map in the appendix. More particularly, the proposed development is ' located in the Southwest Quarter of Section 25, Township 7 North, Range 69 West of the Sixth P.M., Larimer County, Colorado. 1 1 7 L 1 1 II 1 1 1 1 1 1 B. Description of Property The site for Kenny Rogers Roasters contains approximately 0.63 acres of area that is currently a part of the paved parking lot for the shopping mall "The Square". The perimeter of the site is landscaped with turf grass, trees, and shrubs. The property is bounded on the north by East Monroe Avenue, on the west by South College Avenue, and on the east by an entrance drive to the mall. A section of the existing paved parking lot along the south side of the site will remain in place. The site generally slopes downward from northwest to southeast at approximately 5 percent grade. The Larimer County No.2 Canal crosses the northwest corner of the site. DRAINAGE BASINS A. Major Basin Description The site is located in the Foothills Basin. This drainage area is shown on a map in the Appendix taken from a Storm Water Management Model (SWMM) study by Resource Consultants, Incorporated. [I B. Sub -Basin. Description ' Existing developed drainage patterns for the site are southeasterly. Runoff flows offsite along the entrance drive on the west and south side of "The Square'. Flows from "The Square" enter an offsite storm sewer on John F. Kennedy Parkway that carries it to Warren Lake. Sub -basin 1 incorporates the entire site as well as some of the landscaping along the ' north and west sides of the site. This preliminary report addresses no other off -site runoff. ' III. DRAINAGE DESIGN CRITERIA ' A. Regulations All regulations as established by the City of Fort Collins Stormwater Utility will be used for this preliminary drainage study. B. Development Criteria Reference and Constraints Drainage criteria are in accordance with the City of Fort Collins Storm Drainage Design Criteria and Construction Manual. On -site detention is not ' required for the site. The impervious area of the site would decrease from 0.515 acres (existing) to 0.47 acres after the project is completed. Therefore, existing off -site drainage patterns will not be adversely effected at all. Flow patterns proposed for the site will remain nearly the same as for the existing conditions. The only exception is that runoff from the north or ' west sides of the proposed building will be intercepted by the drive -through lane which conveys it around the building. C. Hydrological Criteria The rational method was used to determine the peak runoff peak from the site. The 10 and 100 year rainfall criteria, which was obtained from the City of Fort Collins, is the criteria which was utilized for this study. The calculations are included in the Appendix. D. Hydraulic Criteria ' All calculations within this study have been prepared in accordance with the City of Fort Collins Storm Drainage Criteria. ' 2 I 1 ' IV. E. Variances from Criteria A variance is requested from a required sediment/oil separator with the trash enclosure. A structure like this is more applicable to a restaurant that disposes of large amounts of oil from deep fat friers. Kenny Rogers Roasters cooks using roasting ovens, thereby eliminating the need for sediment/oil separator. DRAINAGE FACILITY DESIGN A. General Concept As construction on the site progresses, the drainage and erosion control concepts shown on the Preliminary Drainage and Erosion Control Plan, in the back pocket of this report, should be followed. B. Specific Details If groundwater is encountered during construction, a Colorado Department ' of Health Construction Dewatering Permit will be required. The site has adequate elevation relief to provide for surface drainage. ' Runoff will flow generally from the northwest corner of the site. It would flow around the proposed building and across the parking lot to converge at the southeast corner of the site (Design Point #1). ' V. STORM WATER QUALITY A. GENERAL CONCEPT Beginning in October of 1992, the water quality of storm water runoff was required to be addressed on all final design utility plans. The Kenny Rogers ' Roasters development is anticipating construction beginning in 1994. Therefore, for this study, we have sought to find various Best Management Practices for the treatment of storm water runoff. ' 3 11 ' B. SPECIFIC DETAILS ' It is our understanding that, for this site, storm water quality should address the prevention of contamination of runoff. This can be accomplished during the daily operation of the restaurant itself. Since most of the site is paved ' parking, sediment control is not going to be a problem. But, the owner should address operational procedures for pollution control and keeping the area trash free. VI. EROSION CONTROL A. General Concept ' Kenny Rogers Roasters lies within the Moderate Rainfall Erodibility Zone and the Moderate Wind Erodibility Zone according to the City of Fort Collins zone maps. The City of Fort Collins Erosion Control Reference ' Manual for Construction Sites specifies that the erosion control performance standard will need to be calculated and appropriate measures taken to control erosion from the site. Erosion control features are shown on the Preliminary/Final Drainage, Grading, and Erosion Control Plan. A sandbag barrier will be the main erosion control measure used during construction. to temporarily detain runoff to allow settling of sediment. Gravel mulch was considered for use over a 4,000 square foot area as erosion protection south of the proposed building. This area currently ' serves as parking for "The Square" shopping mall. Because of the importance of getting this area back in service as quickly as possible, the use of gravel mulch or other erosion protection would not provide the ' intended benefit. Therefore, a variance is requested from the city's criteria by waiving the use of the gravel mulch. Instead, the sand bag barrier will collect the extra sediment and the contractor will be required to closely monitor the barrier and remove the sediment that collects. Since the location of the sandbag barrier is partially off -site, it will be expedient for the the project to minimize problems with "the Square" shopping mall and repave the area as soon as possible. The erosion control performance standard and efficiency for the site during construction assuming the gravel ' mulch is used are shown in calculations in the Appendix. If problems do arise, the gravel mulch can be required at that time. ' All construction activities must also comply with the State of Colorado permitting process for Stormwater Discharges Associated with Construction Activity. A Colorado Department of Health NPDES Permit will be required ' before any construction grading can begin. ' 4 0 1 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. B. Drainage Concept The drainage of stormwater runoff from the site will be less concentrated after construction of Kenny Rogers Roasters than for the existing site conditions. The previous drainage plan for 'The Square" adequately handles the runoff for the existing site, therefore, no site detention nor additional drainage structures are required. Flows in the irrigation canal will remain the same as before the project is constructed. If groundwater is encountered during the construction of any portion of the site and dewatering is used to install utilities, then a State of Colorado construction Dewatering Wastewater Discharge Permit will be required in order for this water to be discharged into any waters of the United States. C. Storm Water Quality ' Because storm water quality has become a requirement, the site will need to address this storm water aspect. After construction, the owner of the restaurant will have to be responsible for keeping the site clean so that ' runoff is not polluted. D. Erosion Control Concept ' Appropriate erosion control measures and calculations of the overall ' performance standard for -the site have been completed according to the City of Fort Collins Erosion Control Reference Manual for Construction Sites. ' REFERENCES ' 1. Storm Drainage Design Criteria and Construction Standards, by the City of Fort Collins, Colorado, May 1984, revised March 1991. ' 2. Erosion Control Reference Manual for Construction Sites, by the City of Fort Collins, Colorado, January, 1991. ' 5 APPENDIX 1 1 1 1 oRT Co�t.iNS � � pVo, i i 1 1 ►� i MoNP�oa Qv. 1 1 � i 1 1 1 VICINITY MAP 1 1 W64 raasi Aol mo 1 it jROAD I 14 21 121 18 r a] � 34 a �\ L5 P RKWAy 25 127STORM SEWER FCC-r4 ► LL s "}�o;AS I f I nl [)a J OR\J --- — �4I 27 3E sire 34 I8'SEWERM 2 S'OR M 2 37 �)v_""r�� <9/ 35 20 �F 120 HYDROLOGY I I I I I I 11 I I T n o II +� ' -U s 3 J II ,. I?o d ' N Z N o 'I w F- A�LL' VJ Q cc:Q LL Z O U a ' Z o CC 0 � U.. Z cn m Z O W PJ F- ' Q > J Q � m U J ' N Q U. IP 1 _1 1 Y /v� I T { 8V Q�s cc Q \� �V U- S r O " r CIO U z °; a O� V i ¢O �g N Q V` V V C O V � � v I W J In 1— > lam. W > W 0° co I l F— to jz ~ W I J QyJ� t^v0 1�, U% J N � c W^ W >+. o i O w N o I� a2 _ z. W i y v I m ^ W V Ao Q oCJ` Q 0 I ,m V/ 0 I _ W -'i ` 0 J Z_ W W z I, z W J Y Z1 C 1 No Text No Text I 1 EROSION CONTROL C k RAINFALL PERFORMP.NCE STANDARD EVALUATION 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 PROJECT: &,AvAJ7 STANDARD FORM A COMPLETED BY: T,`n^ DATE: ll ti3 DEVELOPED SUBBAgIN ERODIBILITY ZONE Asb (ac) Lsb (ft) Ssb ($) Lb (feet) Sb ($) PS ($) MARCH 1991 8-14 DESIGN CRITERIA 1 f 1 1 1 1 1 1 1 1 1 1 1 1 1 1 L 1 1 EFFECTIVENESS CALCULATIONS PROJECT: K�NrJy i2oCaC►2S �oAST 25 STANDARD FORM B COMPLETED BY: DATE: 11 $' Erosion Control' C-Factor P-Factor Method Value Value Comment Gjov G-►aq� 0. 01 1.00 �x15Tinl(y T�LrF (tJr sic�s, VATcE GJOIL— rou3Le•,. -A I , od 0.90 f�4156�,YD 1:,eaaLT ro Pe PC, mmvco f tzerLAZE.D , . A6e4AL-t/-,-, k...�i 116w1ACND 0,01 1 • oo �Sr, )C, fdrnT 16 tz�e L--rrf i '!��7LWP eW3 E>2S 1,00 0.80 ,�J ;'L.AcF, •f Ll�CE A,T � �'OL4� of �j1T"� // . C7��� �LtALkf C�.Oj 1'� eL� Ir::�P 4cm A' MAJOR PS SUB AREA BASIN BASIN (Ac) CALCULATIONS o. 1B5�e, 6FAVEL jA,L tt . 0. AgrAALT VmT: A w N ? NHT�D = (ool• A56 " I.00• Lips t- D.OI • AAe+-O,prj.� 70 "'v �(O.ol•O.I$cjl+C,00•0.13g)r�O.ol'O.ZgS�t(O.oS•O.oi2l�',0.70 C Z =rKl.ao •k�+ 0.90•A*e; 1100 •AAj7 l.0'A41) C"Sc _CCb.1$S �rO.gp•p.13$* O•ZsS+p�Z o.� 0.70 L� o Co. 18 A D.21 >] iflo MARCH 1991 DESIGN CRITERIA ' CONSTRUCTION SEQUENCE ' ^ROJECT: 904617nS STANDARD FORM C SEQUENCE FOR 19,'Id ONLY COMPLETED BY: �PM DATE: IIAZ ' Indicate by use of a bar line or symbols when erosion control measures will be installed. Major modifications to an approved schedule may require submitting a new schedule for ' approval by the City Engineer. YEAR MONTH I ►•1 I tJ I F I M I I M I J I .1 I A-, 1 j OVERLOT GRADING - WIND EROSION CONTROL -.Soil. Roughening_.__.._. Perimeter Barrier Additional Barriers Vegetative Methods Soil Sealant Other k.INFALL EROSION CONTROL ' STRUCTURAL: Sediment Trap/Basin Inlet Filters Straw Barriers ' Silt Fence Barriers _Sand_Bags Bare Soil Preparation Contour Furrows Terracing Asphalt/Con.crete Paving Other - VEGETATIVE: Permanent Seed Planting Fulching/Sealant Temporary Seed. Planting ' sod Installation Nettings/Hats/Blankets Other STRUCTURES: INSTALLED BY IGETATION/Y.ULCHING CONTRACTOR ITE SUBMITTED 1 Y.AINTAINED BY APPROVED BY CITY OF FORT COLLINS ON ' MARCH 1991 8-16 DESIGN CRITERIA O 0 a .o U ' L7 z ■ a a O U O t=a co fLd f-7 to a q H C] H L�] U 1 0 O L'-. ' L-� G a z H 1 0 01 01 0 o O O v v In lc1 u1 u) ggqqq O 010101tT000000 . • . . . • • . . • . O CCCCNlnulLnlnln O to C1 C1 01 01 C1 C1 C1 171 01 C1 C1 O O O O CCCCCCCCCCCCNIn In n g q q O q q q q q q q q q q q 0 h q q q 01 C1 01 11 01 C1 C1 C1 01 01 C1 0.1 01 01 01 01 O CvvvvCvvvvvvvavvvvvv N g q q q q q q q q q q q q q q q q q q q O OnCu1V 101O%0r-r- hhhhhhhq qq.q qq O C C C C C C C C C C C .0 C C C C C C C C C C C C C C .H g q 0 q q q q q q q q q q q q 0 q q q 0 q q co q q q 0 gevnIV0Inn) O�Og170%0hhhhhhhhhhgcoco . . . . • . . . . . . . . . . . . . . . . . . . . . • c, nvvvvvvvvvvvvvvvvvvCvvvvvv g q q q q co q q q q q co q q q q 00 q q q q q q q q co O goNnCClnlnInlnlOU 'V to%D%D%Do%.o% . hhhhh q. n. C C C C C C C C C C C C. C. C. C. V.CC. C. C. C. C. C. C. C. g q q q q q q q q q q co q co q q q q q q q c O q q q q 0 q ci r4 N n n v v n In In ul In In In kD 0 0 r .. . ..... v v In In I��� ............. h n n C C C C C C C C C C C C C C C C C C C C C C C C Co. CO c0 co co co q q C* co q q co q q q CD g q q q q g q co q O 010 q O ri ri N N n n n n C v C C C C C C In In In In k.0 to V. n n n C C C C C V' C C C C C C C C C C C C C C C C C co cocO cocO co co co co co co coLo co cocO co cocJ q- co co co co coq .O NNInhCC100ri.iHrgNNNNnnnnnCCCCC In N n n n n n C C v C C C C C v C C C C v v C C v C C g q q q q q q q q q q q q q q q q q q q q q q COq q N rigrinCtnllllO V hhhggqqqqC1010100000 v NNnnnnnnnnnnnnnnnnnnn4Cvvc g q q q q co co co co co co co q co co q q co co g q q q q q co O oIncoOrgNnCClnLnn00%o V)lOhhhhgggClG1 vraNNnrlc^Ic•�nnnnnnnnnnnnnnnnnnn q G C q q q q 0 m q q q 0 q q G q q q q q q to r{ri0hg00rqNNnnnCCCC-tie InInu1%00 Vr hh . . . . . . . . . . . . . . . . . . . . . . . . . . . c•f rlNNNN_Anonnnnnnnn nnnnnnnnnnn g 0 q 0 0 q 0 q q q q m m q q g q q q q co q q CO co . q O nNo co c% o H N N n n n C C C C C C In In In Ln o lO %o 17 . . rrr1. c. N. NNNN. NNNNNN. NN. NNNNN. . n O g q q q q q q co co g co q q q q q q co q co co c0 q q co co in Ln In C1NnCIn%D h h h q co q C1 C101 C1 C1 C1000000 N C1OO r444rir♦1414ri44r4414141ir- riNNNNN N hcOggqqt:qqqmm co*0m=0mmC*m=mb O %V00nut O 0C1000HrgHr-qNNNNnnnnnn N g0100o00C;c414rir HHOriHT-04ririr-ir{r-Ir•Irqo r-i h h q co g co co q q co co q CO co co g q q q co q q co co co q L7 qN qrgVLnhhgc%c%00ririr-(r-ir1NNNnr)nnn . . . . • . . . . . . . . . . . . . . . . . . . . . . cqq C1 C1 C1 C1 C1 C1 C1 C1000000000000000 h h h h h h h h h h h g q q q co q q q q q q q q q q O % n oC h Cl o rq N n nC Nr 00 In In U' 17 U' Uhh V' IO%.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . H ClOhht�hgggqqcJc;cJqqqqqqqqqqqq In c1 %JO hCOghhhtO0 V U) v v m m ri rq C% k.0 v r-4 m%o 0 oNN NNNNN NNNNNNNNNNNNriri4 4c;(0 h hI h h h h h h h h h h h h h h h h h h N h h h h h 3H--. o0000000000000000000000000 Ot9Ho o0000000000000000000000000 ��v riNnCtnV hq 01HHHrgriririHrir4NNmmvv0 a ' MA.ACH 1991 8.4 DESIGN CRITERIA Table 813 C-Factors and P-Factors for Evaluating EFF Values. ' Treatment C-Factor P-Factor BARE SOIL Packedand smooth1.00 1.00 ................................................................ Freshly disked . 1.00 0.90 Roughirregular surface ................................................ :.......... 1.00 0.90 ' SEDIMENT BASIN/TRAP.................................. ...................,.......... 1.00 0.50111 STRAW BALE BARRIER, GRAVEL FILTER, SAND BAG ....................... . 1.00 0.80 SILT FENCE BARRIER..................................................................... 1.00 0.50 ASPHALT/CONCRETE PAVEMENT ........................................... :....... 0.01 1.00 ' ESTABLISHED DRY LAND (NATIVE) GRASS .......................... See Fig. 8-A 1.00 SODGRASS................................................................................. 0.01 1.00 TEMPORARY VEGETATION/COVER CROPS .................................... 0.45121 1.00 HYDRAULIC MULCH @ 2 TONS/ACRE0.10,21 1.00 SOILSEALANT....................................................................0.01-0.60"' 1.00 EROSION CONTROL MATS/BLANKETS............................................ 0.10 1.00 ' GRAVEL MULCH Mulch shall consist of gravel having a diameter of approximately 114" to 1 1/2" and applied at a rate of at least 135 tons/acre.............. 0.05 1.00 ' HAY OR STRAW DRY MULCH After olantino grass seed, apply mulch at a rate of 2 tons/acre (minimum) and adequately anchor, tack or crimp material into the soil. ' Slope (%) 1 to 05.............................................................................0.06 1.00 6 to 10............................................ 0.06 ................................. 11 to 15............................................................................. 0.07 1.00 1.00 16 to 20............................................................................. 0.11 1.00 21 to 25.............................................................................0.14 1.00 ' 25 to 33.............................................................................0.17 > 33.......................................................................... 0.20 1.00 .1.00 NOTE: Use of other C-Factor or P-Factor u<lues reported in this table must be substantiated by documentation. (1) Must be constructed as the first step in overlot grading. (2) Assumes planting by dates identified in Table 11-4, thus dry or hydraulic mulches are not required. (3) Hydraulic mulches shall be used only between March 15 and May 15 unless irrigated. ' (4) Value used must be substantiated by documentation. MARCH 19S1 8-6 DESIGN CRITERIA E. MONROE BmLmrvc _..__ 6 2784 d 27.84 3111' N S 3496.b- 2088.2% pill 1 I ` I I EAST MONROE AVENUE LARIMER (O. /2 REMOVE EAST. —A o a IRRICA➢nA CANAL 3 ChG k REPLACE MATCH EXIST CAI SEE OETPIL SHEET _ [ !� air- —�� SECTION A -A NTs ce cNc III p -well 'j ti S. COLLEGE AVE, sY III If In 423' S T. _A 1 F.E. 2e.88 1 I B i B 2 2>,�� 9 28.6F' I I o 1 � EXXIST ze �. eee a ch O cal i I I i/ n 2] t_uL' l. E � i I I I Tm. SINS DIRE IOYX"L G I I �25— ry � EXISTING / 1 ! I PARKING �2� / re `REMOVE EXIST CARL ♦ / / x / n NORM OF 4� THIS LINE e� ! EXISTING CURB AVOID - T 1 h GUTTER DAMAGING 1 I EXISTING PVIAC ChG TEMP. EROSION 10 REMAIN CONTROL SAND I BAG BARRIER ' SC4Lf. 1'=20' ¢ �c/ a LEGEND EXISTAC YMYIDLE„ Qr— ye•.r�..", 5.6]C[S O E CF5 ... XISMG FIRE HYDRANT m - wea_ E SNG CONTOUR I ! r t -2A i 0°xa t'CNrnuR Ft LAPA _. Y/!(OtlLJ II 1 n it P h " A In, I. Nc.Tt EXISTIN3 CONTOURS, AS SHOWN, ARE APPROXIMATE ONLY I .''E.rI Lo) IN cr _cT, 1, All �0.l'..D.Ir..: e. — — EROSION CONTROL REQUIREMENTS DF As r cT I were OR 1 1 Irish 1he plain or areas to as q al .n The zbgPa Ranking shall access v timed U to o see b the epoF e i n"V M1[aR� Ll /_ t BSI M+.= is long as possible il p . 1 1 ] A 11 The a b O h II b g l t a t sediment acoasitz. 14A AC BPS F 1 et adjacent a 9^ e y < PRELIMINARY 1 1 _ thelelwe. re shall b take,t p thew aundng a 1 I wanner JANUARY to 1994 a'1 h1 mE t [ me Seeding and landscaping reWlements c e not covered within these p'ms. PRO° ERT+ 9OI'.M1^AR+ INFLOW CURB & GUTTER OUTFALL CURB & GUTTER y Engineering Consultants KENNY ROGERS PRELIMINARY/FINAL DRAINAGE, DEC. n6=-rC: ROASTERS GRADING AND EROSION CONTROL PLAN 4 4 N0. By DATE REVISION DESCRIPTION