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HomeMy WebLinkAboutFOX POINTE PLAZA - PDP - 16-06 - REPORTS - DRAINAGE REPORT2g V I g. 1,500 2,400 0.0p4 0.5 Q4 2,000 0. 0.3 1>000 1,500 0.6 800 0.006 02 1,000 WOW 600 ppp8 0.7 500 800 0.009 0.1 400 0.01 OS 008 600 300 500 0.9 0.06 W 0.05 400 z :3 1.0 0.04 200 300 5 0.03z 002 200 4 z i 0.02 H 100 3 0.03 80 2.5 1.5 / 0.01 v 100 0A4 0.008 60 96 2 c a 50 80 v 84 0.10 p 0.05 0.006 0 o 072 1� x O.o I? 2 0.005 u 50 0 W o.06 u 0 07 / > Q004 3O W 60 W 0.04 W p p 0.003 (n 40 x 70: 54 tL O 0•,' z 20 3O a z 48 1 ? 0.03 c� O,1 U 0.002 1- 942 0.9 U 0.02 a a) Z U 0.8 C OA15cc 3 � 20 a. 33 0.7 < n. Q001 g 10 u 27 0.6 o.o 00 w 0.0008 z 0.5 =5 0.2 ao 0.0006 10 z lw 21 -Z COD 4 = 0.0005 t,i 6 ". 0.4 o / z - -J Q 0004 i 5 a 8 a � IS x z 0. a } 00003 4 6 � 0 0.3 / 5 ; 0.4 S 0 0.0002 0 3 0 12 �,..� -j > 4 05 2 10 0.2 \ 0.6 6 0.0001 8 0.7 7 0.00008 Q15 0S 2 N I cap 0.00006 LO 6 > N ID 8 0.00005 0.00004 0.8 0.1 t- � 9 0.00003 0.6 10 4 10" 05 Q8 Z 0.00002 0.4 0.6 a 2 03 0.5 W x 000001 0.4 3 Q000008 Q2 0.3 0 15 0.000006 1 w 4 0000005 0.13 02 5 0000004 18 i FIGURE 15. Nomograph for solution of the Manning formula. For solution in metric units, see Figure 37. 13 a 11 .Gutter Stdnnt Water Conveyance Capacity for Major. Event Project: Fox Pointe Plaza Inlet ID: design point 1 Top of Curb or yy T Street —Tx Crown Allowable Depth Inlet.)ls, Q-Major i Y Qw I QX'" t d Sx i ble Depth to Gutter Flow Line for Major Event H = 6.0 inches Width W = 1.00 It Depression a = 1.0 inches Transverse Slope S. = 0.0200 ft/ft Longitudinal Slope S.= 0.0054 ft/ft 1g's Roughness n = 0.016 um Water Spread for Major Event T = 21.8 ft r Cross Slope (Eq. ST-8) Sw = 0.1033 Nit Depth without Gutter Depression (Eq. ST-2) y = 5.2 inches Depth with a Gutter Depression d = 6.2 inches r Flow to Design Flow Ratio by FHWA HEC-22 method (Eq. ST-7) E. _ . 0.14 d for Discharge outside the Gutter Section W Cr - W) T. = 20.8 It arge outside the Gutter Section W, carried in Section T. %= 12.4 cfs arge within the Gutter Section W (Q - DO Qw= 1.9 cis Rate Based On Maximum Water Spread Or = 14:3; crs r Spread T = 20.8 ft r Flow to Design Flow Ratio by FHWA HEC-22 method (Eq. ST-7) E. _ 0.14 id for Discharge outside the Gutter Section W (T - W) T. _ 19.8 it arge outside the Gutter Section W, carried in Section T. Q. = 10.9 cis arge within the Gutter Section W (Q - OJ a.. _ 1.8 cis Rate Based on Maximum Allowable Gutter Depth QF = _ _ _ - . 12.7: cis ion Factor for Major Event R = 1.00 Design Conveyance Capacity for Major Event Qrmw - 12.7 cfs 6/13/2006, 3:37 PM '(, STRUCTURAL BMP DETAILS DRAINAGE CRITERIA MANUAL (V. 3) lL-) SD-16 a 8 6 4 2 D = Outlet Diameter or Minimum Dimension, in Inches Urban Drainage and Figure 7 Flood Control District Minimum Trash Rack Open Drainage Criteria Manual (V.3) Area - Extended Range fie: V3-irm Rack 9rfnq Woph. ng Figure 7—Minimum Trash Rack Open Area — Extended Range. Rev. 10-2005 Urban Drainage and Flood Control District 7 DRAINAGE CRITERIA MANUAL (V. 3) STRUCTURAL BMP DETAILS Orifice Plote Perforation Sizino Circular Perforotion Sizing j Chart may be applied to orifice plate or vertical pipe outlet. Hale Diu (in) ' Hole Dia (in) Min. sc (in) Area per Row (sq in) n=t 1 n=2 n-3 1/4 0.250 1 0.05 1 0.10 0.15 5/t6 0.313 2 0,08 0.15 0.23 375 2 0.11 0.22 - --0.33 7/16 0.438 2 0.15 0.}0 O.45 112 0.500 2 0.20 0.39 0.59 9/16 0.553 3 0.25 0.50 0.75 5/8 0.625 3 0.31. 0.61 0.92 11/16 0.688 3 0,37 0.74 1,11 3/4 0.750 3 O.na 0.88 1.33 13/16 0,813 3 a.52 1 1.04 1.56 7/8 0.875 3 1 0.60 1.20 1.80 15/16 0.938 3 0.69 1.38 2.07 1 1.000 1 4 0.79 1,57 2.36 1 t 16 1.063 4 0.89 1.77 2.66 11/8 1.125 4 0.99 I.99 2.98 1 3 16 1.158 4 1.11 2.22 3.32 1 1/4 1.250 4 1.23 2.45 3.68 1 5 16 1.313 a 1.35 2.71 4.06 1 3 8 1,375 - --<- 1,48 2,97 4.45 1 7 t6 1.438 4 1.62 3.25 4.87 1 112 1.500 4 1.77 3.53 5.30 1 9 16 t 5 8_ 1563 _ - 1,625 3.83 _4 4 _1_92 2.07 4,15 6.22 1 tI 16 1.688 4 2.24 4,47 6.71 1 3/4 1.750 4 2,41 4.81 7.22 1 13 16 1.813 4 2.58 5.16 7.74 1 7 8 1.875 4 2.76 5.52 8.28 1 15 16 1.938 4 2,95 5.90 8.84 2 2.000 4 3.14 6.28 9.42 n = Number of columns of perforations Minimum Steel plate thickness 1/4 5/16 3/8 " Designer may interpolate to the nearest 32nd inch to better match the required area, if desired. Rectangular Perforation Sizing Only one column of rectangular perforations allowed. Rectangular Height = 2 inches Rectangular Width (inches) _ Required Area per Row (sq in) 2" I Rectangular Hole Width Min. Steel Thickness 5" 6" 1 4 _/^- 7" 5/32 " 8" 5/16 " 9" 11/32 10" 3/8 " >10" 1 /2 Urban Drainage and Figure 5 Flood Control District WOCV Outlet Orifice Drainage Criteria Manual (V.3) Perforation Sizing Pile: v3-0atlet Detais.dn Figure 5-WQCV Outlets Orifice Perforation Sizing. Rev. 10-2005 Urban Drainage and Flood Control District SD-7 M DRAINAGE CRITERIA MANUAL (V. 3) STRUCTURAL BEST MANAGEMENT PRACTICES m71 0.60 m m m 0.40 E 0 aD C 0.20 U m 0.10 ca 0.04 0.06 0.10 0.20 0.40 0.60 1.0 2.0 4.0 6.0 Required Area per Row,a (in.2 ) Figure EDB-3—Water Quality Outlet Sizing: Extended Detention Basin (Dry) With 40-hour Drain Time for Capture Volume 10-2005 S-73 Urban Drainage and Flood Control District STRUCTURAL BEST MANAGEMENT PRACTICES DRAINAGE CRITERIA MANUAL (V. 3) 0.50 -- T--i-- fihr drain time a=0.7 _.} ,— —_ 12-hr drain time a = 0.8 6ctended Detention Basin 24-hr drain time a = 0.9 _ 40-hour Drain Time 0.40 40-hr drain time a = 1.0 Constructed Wetland Basin 0.35 -- -- -- 24-hour Drain Time -- m t _ _ 0.30-wgcv�Yo.sr3-1.1s;z�o.�a.� _ _. _ — _ 0.20 -- -- --- -- —. —_� — — -- U 3° 0.15 -- -- — -- --- �Wla 0.10 -- — — — — — — Retention Fond. Porous Pavement jDetention and Porous Landscape Detention 0.05 -- -- --- -- 12-hour Drain Time 0.00 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 H1 Total Imperviousness Ratio (I =1 y1100) Figure EDB-2—Water Quality Capture Volume (WQCV), Be Percentile Runoff Event 10-2005 Urban Drainage and Flood Control District I FAA Method City of Ft. Collins Rainfall Composite'C' Area Release Rate (Developed) (acres) (cfs) 0.95 0.73 0.15 Time Time Intensity 10 yr Release Required cum 10 year Flow Volume Cumulative Volume (mins) (secs) (in/hr) (cfs) (CO (cf) (cf) 0 0 0 0.00 0 0.0 0.0 5 300 4.870 3.38 1013 45.0 968.2 10 600 3.780 2.62 1573 90.0 1482.9 15 900 3.190 2.21 1991 135.0 1856.0 20 1200 2.740 1.90 2280 180.0 2100.2 25 1500 2.440 1.69 2538 225.0 2313.2 30 1800 2.210 1.53 2759 270.0 2488.7 35 2100 2.000 1.39 2913 315.0 2597.7 40 2400 1.830 1.27 3046 360.0 2685.9 45 2700 1.690 1.17 3164 405.0 2759.4 50 3000 1.580 1.10 3287 450.0 2837.2 55 3300 1.480 1.03 3387 495.0 2892.1 60 3600 1.400 0.97 3495 540.0 2955.2 65 3900 1.270 0.88 3435 585.0 2849.9 70 4200 1.220 0.85 3553 630.0 2923.5 75 4500 1.200 0.83 3745 675.0 3069.9 80 4800 1.180 0.82 3928 720.0 3208.0 85 5100 1.050 0.73 3714 765.0 2948.7 90 5400 1.030 0.71 3857 810.0 3047.2 95 5700 1.000 0.69 3953 855.0 3098.0 100 6000 0.980 0.68 4078 900.0 3177.8 105 6300 0.950 0.66 4151 945.0 3205.6 110 6600 0.900 0.62 4119 990.0 3129.4 115 6900 0.880 0.61 4211 1035.0 3175.9 -120f 7200 0.850 0.59 4244 1 1080.0 1 3164.2 5 FAA Method City of Ft. Collins Composite'C' Area Release Rate Time Time Intensity 100-yr Release Required ;Cum 100 year Flow Volume Cumulative Volume (mins) (secs) (in/hr) (cfs) (cf) (cf) (CO 0 0 0 0.00 0 0.0 0.0 5 300 9.950 6.90 2070 111.0 1959.1 10 600 7.720 5.35 3212 222.0 2990.3 15 ' 900 6.520 4.52 4069 333.0 3736.5 20 1200 5.600 3.88 4660 444.0 4216.3 25 1500 4.980 3.45 5180 555.0 4625.4 30 1800 4.520 3.13 5642 666.0 4976.3 35 2100 4.080 2.83 5942 777.0 5164.9 40 2400 3.740 2.59 6225 888.0 5336.9 45 2700 3.460 2.40 6479 999.0 5479.7 50 3000 3.230 2.24 6720 1110.0 5610.0 55 ' 3300 3.030 2.10 6934 1221.0 5713.3 60 3600 2.860 1.98 7140 1332.0 5808.3 65 3900 2.720 1.89 7357 1443.0 5913.6 70 4200 2.590 1.80 7544 1554.0 5989.9 75 4500 2.480 1.72 7739 1665.0 6074.5 80 4800 2.380 1.65 7923 1776.0 6146.5 85 5100 2.290 1.59 8099 1887.0 6212.4 90 5400 2.210 1.53 8276 1998.0 6278.2 95 5700 2.130 1.48 8420 2109.0 6310.8 100 6000 2.060 1.43 8572 2220.0 6351.7 105 6300 2.000 1.39 8738 2331.0 6407.1 110 6600 1.940 1.35 8880 2442.0 6437.6 115 6900 1.890 1.31 9044 2553.0 6490.9 120 7200 1 1.840 1.28 9187 2664.0 1 6523.5 �• -4d EFFECTIVENESS CALCULATIONS 1----------------------------------------------------------------------� PROJECT: �d}C PQrNr pckz�\ STANDARD FORM B I 1COMPLETED BY: DATE: bf4in. i I I Erosion Control C-Factor P-Factor Method Value Value Comment ---------------------------------------------------------- I I SED/MF-NT gA5!hJ 1.0o 0+50 I pkv/ &J4 j GOAJC. 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K)ATCrz iviCrkcg &_Fv d-T1 oAj L !DO le 57D/ei = D;,4.S 6UATL2 '�-VCCr-4C4F. FLEV. C /OYl2 57'0%� •' RED r0LumE = 3zo8 C4 0.0i a.G.f4l C0nAULAriVf- VA. (S EXV _ y05 _ 3z 32.5= �PP2ex w• S, �crt:V. @ V = 3ZO2' C F ; 3376 - 5ZOP /G8 = OZ4 et GU�TE2 Sv2F�Ac� �GEv. Vj6n,cv ; 121:a'O, VOLUme _ /S(o$ CF = 0.0ltC.tf• zf vo - / 3S7 - ! 3 Z 3 CF • I Fox PO/'.vrZ '�'4.a-zA I I�r2.a��v,a I T GE �N�Lrses S/TEE �F�%k�GrE.eISTtCS %rFL /g Ac✓esS %7-A4 l yPet2viovs 4'C45A = 0,73 Ac , %9ES/6At Celrgg e,,A ; Q//ow*d4e 2a7Fs McCLZLL.4,vo1,1rA'L C.CF/r!c "�IuNoFF F�Cro,C "C " r-vK FAA DErg"nt oAl c;QC s . de9/NFALC TAJT�NS/TY- /�u24racJ-F,e�gv�Ic� r. 6�Es ; Gary Oc A-o2r ,UA"oAL - 6- 5 Z-t-d, bv�r�2 QvAL�ry C.apTv2� vo�vnz� e D&vrIEr2 d.<64r4 t>rz�rn�aC� FtoDD Co�vrx.aC. GesriC.rC.t' II1�l3AIJ 5 �o2M PRA tiIAG6 GecT �� MA"UcL VOL, 3 ©w2iD G�T�nir�on► VoLvn,c�s. Usr&A�t' rAA ";+�7WoD ;41 A= 0,-73 ec;f Es J(2.= o.45' Ac. _ 0. 37 CA Ac• ,��Qv�2.�p 1/oLv�E : l�SZ3 e•F • (S�r. s�e�.A�st�E�', SH% AoT Facroic✓� Gt, y of Cr; lib. AAJvSrLD Yot, 783o C•F, I 0, is a�� . F©e 101y�e A�966Asg �,�rE = G,z c;SAC x G,�3 Ac. = ,/scA I 3Zo8 c.)c:r, (sE�r�sET, sir, ae-.4 104TEX QvaLJry GaPrv2� foLv,�t� (WQcv) ; 2� USDCM CNApr�2 3 �iG. �Dg -Z rc�� ti 0.qr (5!4r ?) WO CAI = 0. 4-T- a c- x 0, 73 a,c . x %Z _ �• B 3 act �f DESl4AJ \IeLuni = O• 03 ac.;' - X 1• zo = O.03(o ac. = I SGFSCF L 5) Design Criteria Design calculations and methodology conform to the City of Fort Collins Storm Drainage Design Criteria Manual. The stormwater detention basin has been designed for the dual release rates of 0.2 cfs/ac for the 10 year storm, and 0.5 cfs/ac for the 100 year storm per criteria established for the McClelland /Mail Creek drainage basin. Detention volumes have been calculated using the FAA method, and the volume calculated for the 100 year stone has been increased by 20%. Water quality treatment features have been incorporated into the design of the detention facility in accordance with design criteria found in Volume 3 of the Urban Storm Drainage Criteria Manual, published by Denver's Urban Drainage and Flood Control District. Because of the tight constraints on this infill site, it is proposed that the water quality capture volume be included in the 100 year stone detention volume. Erosion Control (1) Rainfall Erosion Control Plan The following erosion control measures will be incorporated on this site: 1. Sediment trap will be placed at the detention pond outlet 2. Silt fencing will be installed along the south property line 3. Inlet filters will be placed at the existing Type R inlet along the mail drop-off lane 4. Vehicle tracking pads will be placed at the entrance to the site 5. Revegetation of disturbed areas will be in accordance with the City's standard general notes See calculations on sheets 4b. 4c and 4d. (2) Wind Erosion Control Plan Since the area to be disturbed is less than 1.0 acres, the exclusion of Section 8.1.1.1 of the Fort Collins Drainage Criteria Manual applies and no wind erosion control plan is required. Preliminary Drainage Study For Fox Pointe Plaza Subdivision Introduction The proposed Fox Pointe Plaza development site includes approximately 1.176 acres and is located at the Southeast corner of Boardwalk Ave. and JFK Parkway, in Fort Collins, Colorado. It is currently part of the Aspen Station Post Office property, which was developed in the early 1990's. The property lies within the McClelland/Mail Creek drainage basin. The proposed development will include a 330 S.F.coffee shop servicing two drive thru lanes, and a retail building with a footprint of approximately 6,000 square feet. Existine Conditions The project site is currently vacant and is vegetated with native grasses, trees and shrubs. The site slopes to the south and east from a high point at the northwest comer. Drainage from the site currently flows to the gutter of an existing private drive serving as a mail drop lane on the Post Office property. This water is collected in an existing Type R inlet near the west end of the lane and then directed to an existing detention basin at the southeast corner of the Post Office property. From there it is discharged into Larimer Canal No. 2. The internal drainage system of the Post Office Property is the subject of the "Final Drainage Report for the Aspen Station Post Office" dated September 10, 1991, prepared by Merrick & Company. Proposed Drainage Improvements The proposed development plan will result in approximately 0.73acres of impervious surface on the project site. Stormwater from approximately 0.65 acre of this total will be routed through a new on -site detention and water quality treatment facility in the southwest corner of the project site. Stormwater from the remaining 0.08 acre of impervious area, cannot be feasibly captured, and will flow into the existing Type R inlet described above. The stormwater detention and water quality treatment facility has been designed to accommodate the fu110.73 acres of impervious surface to compensate for the undetained flow from the 0.08 acre which leaves the site undetained. The discharge from the detention and water quality treatment facility will flow through a 12 inch pipe to the existing Type R inlet described above, and into the Post Office on -site drainage system. Approximately 0.45 acres of the project site will remain in grasses and other pervious landscaped areas. Since these areas have been accounted for in the design of the existing detention facility on the Post Office site, they have not been accounted for in the design of the proposed on -site detention and water quality treatment facility. PRELIMINARY DRAINAGE STUDY DATE: JUNE 14, 2006 FOX POINTE PLAZA ZTI GROUP 2120 SOUTH COLLEGE AVENUE FORT COLLINS, COLORADO J-U-B ENGINEERS, INC. 3538 JFK PARKWAY, SUITE #1 FORT COLLINS, COLORADO PROJECT ENGINEER: TOM CVAR PHONE: 970-377-3602 FAX: 970 377-3935