Loading...
HomeMy WebLinkAboutDrainage Reports - 12/27/1993 (3)Final , pp roved RW PRELIMINARY/FINAL GE AND EROSION CONTROL STUDY FOR KENNY ROGERS ROASTERS FORT COLLINS, COLORADO PRELIMINARY/FINAL DRAINAGE AND EROSION CONTROL STUDY FOR KENNY ROGERS ROASTERS ' FORT COLLINS, COLORADO .1 December 2, 1993 ' Prepared for: Client: ' Curtis Zock 205 Dartmouth Trail ' Fort Collins, Colorado 80525 ' Prepared by: RBD, Inc. Engineering Consultants 209 South Meldrum ' Fort Collins, Colorado 80521 (303) 482-5922 ' RBD Job No. 563-002 P T:JD,NC. Engineering Consultants 209 S. Meldrum Fort Collins, Colorado 80521 303/482-5922 FAX:303/482-6368 November 9, 1993 Mr. Glen Schleuter City of Fort Collins Utility Services Stormwater 235 Mathews Fort Collins, Colorado 80522 RE: 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. ' We appreciate your time and consideration in reviewing this submittal. Please call if you have any questions. rRespectfully, ' RBD Inc. Engineering Consultants ' Terry P. McEnany Kevin W. Gingery, P.E. '7 �� Other Offices: Denver B03/458.5526 • Vail 303/476-6340 1 1 1 1 PAGE I. GENERAL LOCATION AND DESCRIPTION A. LOCATION B. DESCRIPTION OF PROPERTY II. 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 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 3 3 3 4 n 4 5 5 41 ' PRELIMINARY/FINAL DRAINAGE AND EROSION CONTROL STUDY ' FOR KENNY ROGERS ROASTERS FORT COLLINS, COLORADO I. GENERAL LOCATION AND DESCRIPTION ' 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. ' 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 northwestto southeast at approximately 5 percent grade. The Larimer County No.2 Canal crosses the northwest corner of the site. IL 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. t 1 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 .1 E. Variances from Criteria tA 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. ' IV. 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. 1 1 3 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. Gravel mulch and sandbag barriers will be the main erosion control measures used during construction. Gravel mulch will be used over a 4,000 square foot area to protect bare ground south of the proposed building from erosion. ' Sandbag barriers are to be used to temporarily detain runoff to allow settling of sediment. The erosion control performance standard and efficiency for the measures to be used on -site are shown in calculations in the Appendix. 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. 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. 1 4 B. Drainage Conceit 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. .1 1 5 1 APPENDIX 1 oflr 6OLLiNS L-0t-0. 1 1 MoNRoe Av. r� 1 / j � f eei 1 VICINITY�MAP l r ME � le V �am -mms 4 21 121 16 c 18 0 -� 35 --� 25 26 d' STORM SEWER " A i tj P � 24 ---- r- - —�. N OR�J I I 36 27 I N' ire 34 ��-- `_45 18" STORM :: 2 "S7 R M 2 37 ER i� 47 F77T W Z n Z �.3 a 20 R 120 HYDROLOGY I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 4 � $ r n o V � V � m nl N N U. u3 � z OLLJ ~ Q cc: a •` a o z LL U A o cc Q Z Q z O U LL 0 O IL } m (_ Z O � F— > J 0 to U � J N Q u � r W o 0 O obi a ® %n z�u g Vi la V ^ N V r O -1 cnU dr z o� Vr H H it v Q H N 0 �0 9^ v U r. a� 1 U U N N S V � V C O w J to W L _J W 0-.,0 co ( l F— N I Wes~ I J Qy� (D 1� �n U � N J CC W^ W > � 0 O w to c 0 Z W 00 I M m FQ- u N �4 1 pW� a a v 0 Q c --4 � f � G U z FE W W _Z C7 z J 3 _5 C FF- 7 G x aA N I c ao '6ep I I SdJ Q QmaA c u _ u sap — s,o o U CceGYp i fr Q 7_ aCos — sp Lu c a:CY+M;y ff l` I— uoyewwng V N (n s;c co ,av:p Lu a rc CD c, I Q Z e;:e _y. _ easy C I I Q. ¢ ryui l Fysuapul _ r O V N O7c0,apecj = r u .0 uo;:Y:;uaouop f J to sw'l II lI� E mw adldIS I I 0Ulu = uw l ISM I� su'sY9IN m MAY 1984 5-3 DESIGN CRITERIA No Text ' EROSION CONTROL 1 1 / 1 1 1 1 1 1 1 RAINFALL PERFORMF.NCE STANDARD EVALUATION PROJECT:i�ov�ZS %Z�STS STANDARD FORM A COMPLETED BY: -T-4�'n� DATE: IIZ3143 DEVELOPED ERODIBILITY Asb Lsb Ssb Lb Sb PS SUBBASIN ZONE (ac) (ft) ($) (feet) M (�) Moo�e� r� o, 70 L75 5ro MARCH 1991 8.14 DESIGN CRITERIA I fl 11 1 I EFFECTIVENESS CALCULATIONS PROJECT: STANDARD FORM B COMPLETED BY: DATE: t t ff Erosion Control C-Factor P-Factor Method Value Value Comment 'f%tITCG Gjo I L- rou��,2•+-eq � , oo O.OtO �i�'.ia L�'�PHaI-l" To BE I� �+r�o A6r ALt-/,-o,X-.f I.00 jcSTi ��JMT. T t-77e LZ--FTtJ �A24IE1�5 1,00 �,g0 �l AT �;,1T-e /�i 6cpcz or �jl re . NlLU of <c� 1r MAJOR PS SUB FIFA BASIN ($) BASIN (Ac) CALCULATIONS o. 185 II r., o G-7 J AirNALT -�7VMr: AcAP = C,W5�e- y •_1 1 KkE.&4G�hcTa� '�, CO .OI "A56 - I.00 - A-F,5 r 4).0( • AAe o, Crj • - �p /+. �O.O!•O.IQ�j lt{.00•D.I�Ir(D.o!'0.27i S)t(O:OS•O.O�z I�: C.7o T"=�kco-A%4- o.10-A,3; +- 1.00 ',LEAF'` /•`-�rJ'�GM)%b,70,Ko. =rib• IDS �ffl.�(p•Q.l�jSt o-Est^�Z-�fl.�o O . -Jp Q= 0.75 REF�o j l v E ti E �o. 18 # 0,21>, IOo ' MARCH 1991 8-15 DESIGN CRITERIA I CONSTRUCTION SEQUENCE ' ^ROJECT: �o6ZIL5 F�,04S-ra?s STANDARD FORM C SEQUENCE FOR 19, ONLY COMPLETED BY: �PM DATE: fI 4 `�lr3 'Indicate by use of a bar line or symbols when erosion control measures will be installed. major modifications to an approved schedule nay require submitting a new schedule for 'approval by the City Engineer. YEAR °I9 3 l 19 4 MONTH 1 r I M 1 k M I J GRADING IND EROSION CONTROL _.Soil Roughening. _ Perimeter Barrier 'Additional Barriers Vegetative Methods Soil sealant Other PAINFILL EROSION CONTROL ' STRUCTU-RAL: Sediment Trap/Basin Inlet Filters ' Straw Barriers Silt Fence Barriers _San d_B a g Bare Soil Preparation ' Contour Furrows Terracing Asphalt/Concrete Paving ' _Other -(astgvFL /ANL,�A — VEGETATIVE: ' Permanent Seed Planting Mulching/Sealant Temporary Seed Planting ' Sod Installation Settings/,vats/Blankets other STRUCTURES: INSTP*LED BY LETATION/MULCHING CONTRACTOR IF a SUBMITTED MAINTAINED BY APPROVED BY CITY OF FORT COLLINS ON ' 1: ARCH 1991 B-16 DESIGN CRITERIA 11 1 O A 0 a O U z - H a a ' O U ' O f�a F4 Pi Ca 0 aLO m Ca E4 U ' 0 L-i a F4 z z H o rncl000 O <rU7N4l - 47 ggqqq O C101 � �000000 O rr<rlfi Ul L�U)U1 L7 < ggqqcoC'Oqqqco O q Cl Cl n Gl Cl Cl n Cl C1 Cl Cl O O 0 O rrCC<C<CC<Cr In LO Ln n q q C3 c0 co co q q c0 q q c0 co q q O hggqClCICTCICICIClClC1ClD1mm clmm O C<< C C< C r C< C C<< r<<< r< N Cpggqqqqqm C*0 ggco O 0nCIn0ICV)0hhhhhhhhhhhhcoco m. co co co O r C< C r 444 <r r .« r r C. . C r C r r< C C C C .i CCqggqqqqcOqqcoqqccoqqcoqqqqqcom 0 co N m IV 0 0 0 %D Lo V' %-D V Ohhhhhhhhhh co c4 n«<r<r<r«<r<r««rr«r« gggC9qqqCJqOqqqqcJqpqqq q q q qqq O 170Nn «L7 U1 In U1 l7 l'� rU U1 1�1� V1 t hhhhhh . . . . . . . . . . . . . . . . . . . . . . . . . . . q n C< C r r C< C< r<< r r C<< r C r< C « < co co q cJ q CO CO q cO q q co q co q q q q q q q q q C) CD c0 O rClriNnnC<C<rLe) U1U1Lei NU1U1U1inL7 V V kDl7Oh . . h n n< C r r< r r « c r C<< r r< r C C r<< r co q co CD c0 co co co q c0 co co coco co co co co co co CD CO c7 CO CDq O OtD q O ri ri N N n n n n rC rC C C< C In Ln Ln U7170 . . rlnnr. . . r. . . . . . . . . . . . . . cr<cr««r<c <v<r<crc< coCD cogcoqqqqcOMqqC7qqqqqCJqqOcOq LO Nl U7 h q cl O O H ri H N N N N N cl C'1 n n nr C C r. . . . . . . . . . . . .Nnlnnnn«<r<c<r««<rrr«« g q i q= q q q q q q q q q q Q c0 co co q co q t0 q c0 q q a CSCtn rigrin<U1Le) UV hhl'hcococoggc3c%c, %00000 p . -a< NNnn�"1nnl"Innr'lrinrlrinnnnnn<�r<�< COq 0 q QgGC7q ca ggInq gmco co O V' lnl q 0 r4 N n C C LnU7 In l7 '0 1D tD l0 h h h h. . . . cJ q q Cl n . . • . . . . . . • . . . . . . < ri N N n n n n n n n n n n n n n n n n n n n n n n n coq g q q C* C3cJ cO m ca coq q coq q q m co q q q C0 co co U) r4H' )hg00 4rlNnnnCr<CCIn V)L7l7l7lChh n r i N N N N n n n n n n n n n n r 1 n c 4 n n n n n n n n co q q q co co CO c0 CDco CDC co co cocq co co co co C3 coc0 coco co O n N O CD CI O ri N N n n n-IV <CC<Cln In n Ln kD rU V Q . . . . . . . . . . • . . n 0r-4 ri ri r g N N N N N N N N N N N N N N N N N N. N NN q ql co cocJ co co c0 cocO co co c0 co coco co CD coCJ co 0 CD coco CD in 9 NC1 NnC L7 Vr hhhq 99 nC!C1 C1c c c1 90000 ........ N C100Hr-gHr�r�4ririririr-qr-4'ir..4rq Iri {NNN.NNN h q c0 c] CO CO O g CO q q q q Cq q q c0 co q CO CO co q q q co O rU1�0 nIn l7 CO CO Cl O 00 ri ri H ri N N N N n n n nnn N lco mla 000000 r1ririri ri r-{ri ri ri ri r-{r{r.l r..4 ri ri r� h h ca q OD C) q O CO cq c] co co co co CO CO CO CO q q q CD CD CD co L'1 qN�q r-4C L7hhC)G1 G100r-{r{ri r-{riNNNnnnnn . . . . . . . . . . • . . . . . H l7 qCO Cl C1Gl C1C)C%nollo000000.00000000 h hI h h h h h h h h h cO co q q* co g q q q q q q co co O k C)0<hC10rqNnn«InU1U)Lo o %Dt.00hh0l7U . . . . . . . . . . . ri CUr h h h h q C3 q q q q q q c0 c0 c0 co q q q cJ co q co co h h h h h h h h h h h h h h h h h h h h h h h h h h U1 C10(C 'o h CO q h h h 0 1.7 to U1«nnNN C%t. Cri C1 V' O O41( Nr Nc NNNNN4r Nr N NNrir-{riri00 h huh h h h h h h h h h h h h h h h h h t� h h h h h E-4 0000000000000000000000000 I O C7E1 0 0 000000000000000000000000 r7..(:.r riNln< In O h q Cl O H N n C In 0 h q C% O L70 U7 O In0 av H H H rq r i ri H H H ri N N n n<Cn ' MARCH 1991 8.4 DESIGN CRITERIA ' Table 86 C-Factors and P-Factors for Evaluating EFF Values. ' Treatment C-Factor .P-Factor BARE SOIL Packedand smooth................................................................ 1.00 1.00 Freshly disked ........1.00 0.90 1 ........................................................... Rough irregular surfacee1.00 0.90 ' SEDIMENT BASIN/TRAP.................................. ............................. 1.00 STRAW BALE BARRIER GRAVEL FILTER SAND BAG ........................ 1.00 0.50111 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 SODGRASS ............ :.................. .................................................. 0.01 1.00 . 1.00 ' TEMPORARY VEGETATION/COVER CROPS .................................... 0.45121 1.00 HYDRAULIC MULCH @ 2 TONS/ACRE.................6......................... 0.10" 1 1.00 SOIL SEALANT........................................................... 6........ 0.01-0.60i1 1.00 . EROSION CONTROL MATS/BLANKETS ... 0.10 .................................. ..... 1.00 GRAVEL MULCH. Mulch shall consist of gravel having a diameter of approximately 1/4" to 1 1/2" and applied at a rate of at least 135 tonslacre.............. 0.05 1.00 ' HAY OR STRAW DRY MULCH After planting orass seed, apply mulch at a rate of 2 tons/acre (minimum) and adequately tack or crimp material into the soil. anchor, ' Slope M 1 to 05.............................................................................0.06 6 to 10............................................................................. 0.06 11 to 15............................................................................. 0.07 16 to 20........................................................................... 0.11 1.00 1.00 1.00 . 1.00 21 to 25............................................................................. 0.14 1.00 25 to 33.............................................................................0.17 1.00 ' > 33.......................................................................... 0.20 .1.00 NOTE: Use of other. C-Factor or P-Faror values repo^ed in this tzb!e must be subst mi iated by docurnentt-tron. (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 betv:een March 15 and May 15 unless irrigated. (4) Value used must be substantiated by documentation. 1 ,' MARCH 1991 8-6 DESIGN CRITERIA .1