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HomeMy WebLinkAboutDrainage Reports - 06/07/1993PSOPERTY OF FORT COUANS roux s FINAL DRAINAGE REPORT for O A K R I D G E B L O C K O N E F IRS T F I L I N G Fort Collins, Colorado JUNE, 1993 ' prepared by NOFRTH ERN ENGINEERING SERVICES, I NC 420 South Howes, Suite 106 Fort Collins, Colorado 80521 (303) 221-4158 Project No. 9301.00 June 7, 1993 Ms. Kathy Malers Stormwater Utility City of Fort Collins 235 Mathews P.O. Box 580 Fort Collins, Colorado 80522-0580 re: Oakridge Block One Final Drainage Project No 9301.00 Dear Kathy: Northern Engineering is pleased to submit this report of a stormwater investigation for the Oakridge P.U.D. It represents a study of existing and proposed runoff characteristics of project site. A study of soil erosion at the site is also included in this report. We would like to thank you for your valuable input during the research phase of this study. If you have any questions or comments as you review this report, please feel free to contact me at your earliest convenience. Sincerely, ,,---'----NORTHERN ENGINEE Terr P. McEnany Reviewed by kcal SERVICES, INC. REC""'' a C" 25033 e P.E. ° 4 > U. SadorS t� I o o EN RaW ,co S`a pc P e i c 0 E R. J \ ' r Ct I i WdAAEN LAKE ; Lowe st f :-... ° , A Ewe~ a nder `ppo �c; . c t u a ! o Sum ZtoMe� Caribou 3 West Core on Or a Q ) c �� Br hor `�� ao� e q a f(Z ��d eQfk°bor Wo/k Devon °� B . o o �C' 0#1 S e C / I U Or w N �1,� rQ'i � r Dr. orthe:t� Shoe` CR // Cj A.f•QSb V �Cl/ Sod _ Revere Z Co77d M 3{ Covey ' v Ct.' o Co e o I ,�. f yy Whebtcn Ur No Ct. 8 Morre� I 1 g Y>t�e� v ' N K 3 m ante Cor/ Ot' O hoard Ln. : v --f---,Timberline a M )rmony Rood € ' \ Ln_ PROJECT SITE Dr. oky Dr. O / m Oakrid e c V4 / Rule Or 5 1 Og\ ive Ook U• �.� Red Oak Ct bef p _ oolh p: .Oox Do k Ct' , toe i 1 I Final Drainage Report for Oakridge Block 1, First Filing Fort Collins, Colorado 11 June, 1993 I. GENERAL This report summarizes the results of a storm drainage study conducted for the proposed development of Oakridge Block 1, First Filing to be located in the Northwest quarter of Section 6, Township 6 North, Range 68 West of the 6th Principal Meridian, in Fort Collins, Colorado. Methods outlined in the Fort Collins Storm Drainage Design Criteria were used in the calculations for the stormwater runoff portion of this study. The Rational Method was used to estimate peak stormwater runoff from the site. Summary calculations and other supporting material are contained in an appendix to this report. II. SITE DESCRIPTION The existing improvements on the site are an irrigation ditch and structures that have been abandoned, a major drainage swale, 1 culverts, and curb inlets. Two storm pipes deliver runoff to a swale that begins at the northwest corner of the property. Flows are carried southeast to three 36" culverts that cross Oakridge Drive. An abandoned irrigation ditch runs along the west side of the site. Vertical curb and gutter and an eight foot detached sidewalk run along Lemay Avenue. A curb inlet exists on Lemay 1 Avenue near the northwest corner of the site. Two more are located on Oakridge Drive near the three 36" culverts. The land currently is undeveloped grassland. Vegetation on the site includes a row of old cottonwood trees along Lemay Avenue. Many young cottonwood shoots have started growing in the major drainage swale. The rest of the sight is covered with native and planted grasses. The site slopes gently downward toward the drainage swale at approximately 2.8 percent. The bed slope of the swale is approximately 1 percent. Oakridge Block 1, First Filing Final Drainage Report page 2 III. HISTORIC DRAINAGE Most of the runoff from the site drains into the drainage swale running southeast to the three 36" culverts at Oakridge Drive. The west edge of the property drains to the east gutter on Lemay; most of this flows south to Oakridge Drive and then east to the north inlet on Oakridge Drive. The other portion flows north to the inlet on Lemay Avenue and then into the drainage swale. The historic sub -basin that was identified as H2 on the preliminary drainage plan is the only basin affected by this project. The runoff coefficient for grass land (C = 0.20) was used to obtain 10 and 100 year peak stormwater flows at design point (D.P.) 2. Table A shows the results of peak historical runoff calculations (H2). IV. PROPOSED IMPROVEMENTS The development of the site would include two commercial buildings and a new street. The new street would provide access to the driveway entrance for the buildings. The drainage swale from the northeast corner would be changed to a storm sewer (Line 'A') that would convey off -site flows and Pond 'A's detained runoff. The storm sewer would follow the west side of the property offset east 15' from the existing sidewalk and daylight after crossing the new street (Haxton Drive). The flow would then be carried in a swale that parallels the south R.O.W. of Haxton Drive to the three 36" culverts. Runoff from sub -basin d2 would be ' collected by inlets B1 and B2 of Storm Sewer Line 'B'. Detention Pond 'B' would be constructed to hold runoff col.lected in Line 'B'. The pond outlet would then release the detained flow into the Haxton Drive Drainage Swale just above the three 36" culverts that cross Oakridge Drive. The offsite detention basin offers flexibility to the developer to chose alternative detention schemes as each phase is designed. The basin size can be changed to accommodate different storage requirements in order to achieve the 0.5 cfs per acre release rate. The design of Pond 'B' is adequate to hold peak runoff for this phase of development only. Flows from outlaying areas are allowed to pass through undetained until those areas are developed. The outlet control will have to be modified each time the flow into either pond is changed. Oakridge Block 1, First Filing Final Drainage Report page 3 1 V. DESIGN CRITERIA The Oakridge Business Park Drainage Report (RED, Inc. 1990) specifies a 100-year flow rate from the existing from Lemay Avenue equal to 10 cfs. It also gives storm sewer coming the 100-year peak flow entering the northwest corner of the site from the north through a 29"x45" horizontal elliptical culvert as 58 cfs. Thus, ' the majority of flow from offsite and runoff from the site flows into the Oakridge drainage swale. The three 36" culverts crossing Oakridge Drive conveys approximately 71 cfs under a headwater ' elevation of 4975.78' amsl according to the report. Drainage and grading for this site has been designed on the premise that site runoff would be detained and released at a rate ' of 0.5 cfs per acre for each phase of development as required by the Oakridge Business Park Drainage Report (RBD, Inc. 1990). A portion of the runoff from Lemay Avenue will be diverted by the new street, Haxton Drive, and has been included in the calculations for release without detention through Pond W . The flow from the adjacent area southwest of the site and also east of the site has also been routed through pond 'B'. Pond 'B' has an overflow spillway that will pass the peak rate of flow into the swale should the outlet become clogged. Emergency spill from pond 'A' will flow into the parking lot through the drives around the east building of the site and then into Storm Sewer Line 'B'. Pond 'A' has been oversized to allow for the future detention of runoff from the adjacent land to the east. . Ten-year runoff flowing east in the gutter approaching the north inlet on Haxton Drive will overflow the crown of the street. The gutter's capacity decreases with slope as flow enters the sump area of the inlet. The inlet opening has sufficient capacity to receive the flow so, in reality, there may not be cross flow. The sidewalks are detached and are above the estimated 0.7 foot depth for normal flow at 0.4% grade. In consideration of the problems to traffic, Haxton Drive is short and vehicle speeds would probably be low. Thus, it is doubtful that cross flow would cause any problems to traffic if it does occur. Therefore, a variance is requested from the street capacity criteria for minor storm runoff that prohibits cross street flow I tOakridge Block 1, First Filing Final Drainage Report page 4 ' VI. EROSION CONTROL . It is anticipated that the proposed improvements for the First Filing will be completed by August of 1993. Overlot grading is to begin in June, 1993, with utility, street, and building construction to follow. Temporary erosion control measures consist of gravel filters to be placed around the two new inlets as shown on the attached Drainage Plan as well as the west inlet on Oakridge Drive. The filters should be monitored by the contractor during construction ' and maintained as necessary. Straw bales are to be placed around all culvert entrances. Straw bale dikes must also be placed every 200' along the open swale to protect the channel banks from erosion prior to revegetation of the area. The gravel filters shall be constructed immediately after construction of the inlets and be maintained until the First Filing improvements are in place. See Drainage Plan for construction details. Permanent vegetative erosion control' will be used in conjunction with landscaping. Permanent revegetation of areas ' disturbed by construction will be the responsibility of the contractor. If reseeding, application shall be by drilling and protection by crimped straw mulch immediately after drilling. The straw shall be applied at a rate of two tons per acre (minimum). Sod may be used instead of seeding as determined by the developer. I 1 I I Dakna�ye 8loc�1r i ✓lad �rct n�� /blw,a . 0 /� f o,, PeAok 4d1c- A4 �2 G� 6ld z,?s 2.74 �1 �/dys, �,� • d,¢� o 403 1.So o, 9s 2.17 . p.Zo o,oq. Z, a,9S o. Q-S o , zS" o. Z(o O. 7/ 2 t k; 2. 2(o Q Z Z 4d2 - o. 47 .1 1 d Z z.z� «ao8 76' �6(O.Zo)= 0 73 i [1 pra:Nn.u_•l1e J /�i.c-✓t D � Ga- !G t,..-f t.� rc�-s�5 td5 � K �„ e . a4 oT Utz: hI&xfah or. io de&�, f loin D, P. 'e' i's at �,e Oct/ lelra y+ti oxs'Ae �/ (Dr IGP/<1#04V Af P,P, %,G0* : p►6J W— 1 L=Z33' �. P. b 3.0 % p;P46 �,( -x I. Soo' (D 2.45' /o i I TABLE A CALCULATIONS calculating Table A is based on City of Fort Collins' criteria for stormwater runoff using the Rational Method. Notes each on column contained in the table appear below: ' 1. DP: Design Point. May be either a total contributing basin flow (e.g. H1 or D2) or point flow at a Design Point (e.g. DPI). I, 2. Area: Area contributing flow to the Design Point, in acres. 3. Overland Flow: a. C: This is the runoff coefficient for the overland portion of the flow only. ' b. L: Length, in feet, of flow path. Lmax = 500 feet. C. S: Average flow path slope, in percent. d. tc: Time of Concentration of the overland portion of the flow, in minutes. tc=[ 1 .878( 1. 1-CfC)Li/2i/sI/3 Where: Cf2=1.00 and Cflao=1.25. 4. Gutter/Pipe and Swale flows: Channelled flow paths in either gutters, pipes or swales. May be undefined watercourses which occur naturally. a. L,S: As in 3.b and 3.c, above. b. V: Flow velocity from nomograph, attached. C. tc: Time of concentration, in minutes. tC=(L/V)(1/60). 5. Tc2, Tcloo: Total time of concentration, in minutes. ' 6. i21 itoo:. Rainfall intensity, in inches per hour. ' 7. Q21 Qioo: Peak runoff, in cubic feet per second. Q=CCfiA. I 1 TABL9 e STORNNdTBR RUNOFF O11RIDG1 BLOC[ I, FIRST FILING FIN6L OYBRLdND ; GUTTBR/PIPB ; SNALB ARBI ; C L S tc10 tc100 ; L S F tc ; L S T tc ; Tc10 TcIOO ; HO i100 ; C ; Q10 Q100 D.P. (ac) ; (ft) (1) (via) (min) :(ft) (S) Ws(lio);(ft) (1) Ws)(oin):(min) (win) ;(i/h)(i/h) ; ;(cfs) (cfs) HISTORIC : : 1 ; 9.25 :0.20 380 2.4 24.5 23.1 ; 0.0 ; 400 0.75 3.8 1.8 ; 26.3 24.9 :2.75 4.60 :0.20 5.09 10.64 DBFBLOPBD a 1.50 :0.25 233 2.7 17.5 16.2 ; ; 17.5 16.2 :3.40 5.70 :0.52 : 2.65 5.56 b 3.14 :0.20 250 3.0 18.5 17.4 50 0.4 1.5 0.6 19.0 18.0 :3.30 5.50 :0.75 ; 7.77 16.19 c 2.88 :0.20 250 3.0 18.5 17.4 18.5 17.4 : 3 . 3 6 5.70 :0.73 ; 7.06 14.98 d 2.48 :0.20 40 5.0 6.2 5.9 ; 485 0.4 1 8.1 : 14.3 14.0 :3.70 6.10 :0.81 7.43 15.32 e ;. 6.42 :0.20 300 2.5 21.5 20.3 ; 120 0.40 1.5 1.3 22.8 21.6 :3.00 5.00 ;0.47 ; 9.05 18.86 NOTES: 1. D.P. T: Sub -basin d2 offsite area to B, with the Design Point at T, 2. D.P. Y : Sub -basin d2 with the Design Point at T. 3. D.P. T : On -site area that contributes flow to the 8N gutter of N inlet on Easton Dr. 4. D.P. T : Total runoff for design of Food T spillway with the Design Point at Y . r I No Text L 1 I r U? I i I I -641- U �QaK/pc�. SLocl� S, �rs!-��Ky c �S At - z 7e s ape ---� �'i.�Q ,�► �aa� e4 w.t � 6i 2 't,� = D. rj � � 'Yl = O. OI ,b � {esr�. CL�•�.N�� f 5 � r¢� J ZA `%, oiy = 3/Z5' Q• - �o its ' b O L}5 ele:�p 0,<<�t _ D,S� = S c< 7.4.3 c{ A� lel z`Xe, ' �r7 CvOSs 6Ve--") lb /kf J /H� / r (d?f 'sI. l tle *qe-j f / S d��.�Z a.y wE /'s not u va 6 l 1 _ � 6000 7000 6000 5000 4000 2000 1000 900 �7 0 0 s00 O 400 Q300 cc E 200 6o 70 60 50 40 J-J 20 [us i E, r — L EQUATION: 0 • 0,54 n IS ROUGHNESS COEFFICIENT IN MANNINO FORMULA APPROPRIATE TO MATERIAL IN EOTTON OF CHANNEL E IS RECIPROCAL OF CROSS SLOPE REFEPEMCE H A. E PROCEEDINGS 19". PAGE ISO, EQUATION 1141 EXAMPLE (SEE GAINED LINUI Given, 2 0.03 100 2 tR j TO n • or 11 aIn • Itoo tL 50 0 • 0.22 V 30 20 FIND 0 • t.0 ITS 1_0 Ip - Y \� INSTRUCTIONS'\� '� I. CONNEOr aln AACO wI r" SLOPE 1 ANO CONNECT DIl GMARO[ 101 wITM UVT" lyl THESE TWO LLIINI�AIUSI INTERSECT AT TURNING LINE EOR�"' COMPLETE SOLUTION 2.FOR SHALLOW Y-SHAPED CHANNEL AS SNOW" USE NOMOGRAPM WITH I L 7 10 06 07 06 ~ 05 .04 U. 2.0 IN 60 70 60 .50 t,L 40 Z i " 4CT5 Z .30 2_ .02 O , .20 3 w .2 0 I _j .01 _z O cr- .07 w a Q O5 Z 03 Z .006 "o ~ .02 Q 007 •...,.1' ',ol U .006 �— .005 .004 W a 3 TO O[TERMIxE a —!-y O .003 H-[ DISC AMOE 0 IN t N y ,yS PORTION OF CHANNEL IL _ .I', U) x ANlx4 NIDTH 9: 1—IT DETERMINE DEPT" J FOR TOTAL DISCNA+c[ I" .00 2 . ENTIRE SECTION O THEN USE xOMOORAPN TO DETERMINE ON IN SECTION O FOR O[PTN . TO OE TERYIx [ 013DMARaE I Ix GOYPOlII[ S[CTION T' a a±j y �• FOLLOW INS1NucilOx S i ,.• '• To o2rum N scNARCE 1x - ""- -" ""-- .001 " 9ECTION a AT ASSUMED I•ly.y 1 0[PT" y 021FIN 0 FOR From BPR SLOPE RATIO EF AND DEPTH J THEN OT . 0, • O, Figure 4-1 NONOGRAPH FOR FLOW IN TRIANGULAR GUTTERS (From U.S. Dept. of Commerce, Bureau of Public Roads, 1965) U) .10 W a w os 0 .07 06 Cr. 0 .05 co Cr .04 U .03 Q ~ 02 a W C) 01 MAY 1984 4-3 DESIGN CRITERIA ' Pressure Pipe Analysis & Design Circular Pipe Worksheet Name: OAK Comment: STORM SEWER LINE 'B' CAPACITY ' Solve For Discharge Given Input Data: Elevation @ 1..... 78.14 ft ' Pressure @ 1...... 0.00 psi Elevation @ 2..... 77.50 ft Pressure @ 2...... 0.00 psi Diameter.......... 27.00 in Length........ 70.00 ft Hazen -Williams C.. 120.00 ' Computed Results: �+ Discharge ......... 15566 .64 qpm = 34- c Velocity.......... 8.72 fps ' Headloss.......... 0.64 ft D•P. 6� o� Energy Grade @ 1.. 79.32 ft �rc� pry, R{�BSt Energy Grade @ 2.. 78.68 ft �+ / ' Friction Slope.... 9.143 ft/1000 fit. (fit ✓.M kS,K ' V3 7L7 Pogo Z7"Pti 360' 22x$4I4F�G/p Open Channel Flow Module, Version 3.42 (c:) 1991 Haestad Methods, Inc. * 37 Brookside Rd * Waterbury, Ct 06706 .1 C/�✓/GZ' .CJ60CK 1. / � sf/E �i n y �Ct T 77 s' L = 70' D = Z7 „ Q - err/ Z = IV-%r �7 �p s ¢ 1 z 3-3.45 �s .m r /a 0�4K20G I C • e-� U N �-- 44x o� ' �o = D, .s / r �L (SST, / SG,rZB►c1 n t Z i� - �. D ' 1 G'a/ca ci �y t'f of fry r=> OL ✓PduCt;,, • 5 , � ee tti ere cJ: �/ 6e C'ro SS s7 of �-/ / /.car du.`; �r g �'e lon /,-. co.yr - s �•��/e. fs �t'%XTo.J ( cJ,l� h -=-,e?fle %e 1/6 et.) foe �"rSt /`�.�� le,.e/o�.�, - 1� //Df` fie /mli1 �t X;Ieey �f.�cc' e2 fl-&� f u // %e ve%w -clt� l4GS oe'e 4c�5 r reC' ' Tel lA le t G-. Q,o � G25� ZS' 1046 31, ZSc�t '�'j 31.42c� 1 Li 1.0 12 ' 5 .9 11 10 4 8 10 3 .8 � 6 9 2 w 4 i/U- 7 8 w 3 %� / z 1.5 6 7 � w r E z 1.0 ' .5 6 __ Example, Part o_ 1•0 z .9 w ' 5.5 a ----- Q. .8 r- U) .6 w w C7 U- w 5 x z o .7 tL .4 z Z 4 ►- z 4.5 z o 3 w 6 w t w x 4 = 0 o 5 ' z o = •2 _z �- zCD 0 .3 3.5 z z a.w w _ 4 a o: 0 u w 0 .25 3 0 0 •08 = 0 .06 .3 w w z ' 2.5 x w .04 w .25 .2 a .03 f- 3 a 02 0 .2 2a. a x U t- a .15 .01 .15 L w 4 1.5 -- y0 ' 0=2' h .10 .I 1.2 Figure 5-2 ' NOMOGRPAH FOR CAPACITY OF CURB OPENING INLETS IN SUMPS, DEPRESSION DEPTH 2" Adapted from Bureau of Public Roads Nomograph MAY 1984 5-10 DESIGN CRITERIA CZ Pipe- , s( li = Cb�2 c IG vErL j . G 73.44 G+r(aa.l aiC.L ; 71-35, �7 p pc -� o, Z I p�yc W4No� ,v uzic 4tc� a M arm.. Ic, n. cm„�c, pc,a Z- -�- 3 4 a � 79•SD N ti \ -77 P&I Zf9� e 7c.G6 o.y7 it) q.=-14 1-4 A', `re2 LD US)u4 5-T4p1,,415L IkJ LC1 $ 3-3 6 nc-p it- 7 4-210 �S 38 IZs� e / — 717--�- QL - — z z r —1 SbbL+ D, + z� = Te o� -t Dt + L z, {- 4 Czz� 1 CM 4J ; 4-3I j Q4� Oakridge Block One, First Filing Stepwise Backwater Calculations (Morris & Wiggert) 100-Year backwater, Storm Drainage Channel A Sta D1 D2 --------------------------------------------------------------------- Q n b z Ib SUM L WSE 22.00 76.93 0+22 1.55 1.60 68.0 0.028 2 4.00 0.00.50 22.48 76.98 0+23 1.60 1.70 68.0 0.028 2 4.00 0.0050 28.21 77.11 0+27 1.70 1.80 68.0 0.028 2 4.00 0.0050 50.21 77.32 0+50 1.80 1.88 68.0 0.028 2 4.00 0.0050 147.90 77.89 1+48 1.88 1.90 68.0 0.028 2 4.00 0.0040 164.49 77.98 1+64 1.90 1.97 68.0 0.028 2 4.00 0.0040 310.52 78.62 ' 3+11 1.97 1.90 68.0 0.028 2 4.00 0.0097 317.98 78.63 3+18 1.90 1.80 68.0 0.028 2 4.00 0.0097 330.16 78.65 3+30 1.80 1.70 68.0 0.028 2 4.00 0.0097 344.61 78.69 ' 3+45 3+63 1.70 1.63 1.63 68.0 0.028 2 4.00 0.0097 363.10 18.80 1 .1 f Trapezoidal Channel Analysis & Design Open Channel - Uniform flow Worksheet Name: trap channel Comment: Normal depth for Haxton Channel Solve For Depth Given Input Data: Bottom Width..... 2.00 ft Left Side Slope.. 4.00:1 (H:V) Flight Side Slope. 4.00:1 (H:V) Manning"s n...... 0.028 -w(::hannel Slope.... 0.0050 ft/ft Discharge........ 68.00 cfs Computed Results: Depth............ 1.88 ft Velocity......... 3.81 fps F"low Area........ 17.86 sf Flow Top Width... 17.02 ft Wetted Perimeter. 17.49 ft Critical Depth... 1.55 ft: Critical Slope... 0.0123 ft/ft Froude Number.... 0.65 (flow is Subcritical) r f'— o . 5 A55 v MGO Cleo rAe-1 m( Open Channel Flow Module, Version 3.42 (c) 1991 Haestad Methods, Inc. * 37 Brookside Rd * Waterbury, Ct 06708 I LOS 1 Trapezoidal Channel Analysis & Design Open Channel - Uniform flow Worksheet Name: trap channel Comment: Normal depth for Haxton Channel Solve For Depth Given Input Data: Bottom Width..... Left Side Slope.. Right Side Slope. Manning's n...... —+ Channel Slope.... Discharge ._...._. Computed Results: Depth............ Velocity......... Flow Area........ Flow Top Width... Wetted Perimeter. Critical Depth... Critical Slope... Froude Number.... 2.00 ft 4.00:1 (H:V) 4.00:1 (H:V) 0.028 0.0040 ft/ft 68.00 cfs 1.97 ft 3.50 fps 19.42 sf 17.74 ft 18.22 ft 1.55 f t 0.0123 ft/ft 0.59 (flow is Subcritical) Open Channel Flow Module, Version 3.42 (c) 1991 Haestad Methods,.Inc. * 37 Brookside Rd * Waterbury, Ct 06708 11 u 1 '' I I .1 I I I .1 .1 Trapezoidal Channel Analysis & Design Open Channel - Uniform flow Worksheet Name: trap channel Comment. Normal depth for Haxton Channel. Solve For Depth Given Input Data - Bottom Width..... Left Side Slope-, Right Side Slope. Manning's n...... (channel Slope.... Discharge........ Computed Results: Depth-----,....., Velocity .... ----- Flow Area........ Flow Top Width... Wetted Perimeter. Critical. Depth... Critical Slope.-. Froude Number.... 2.00 ft 4.00:1 (H:V) 4.00:1 (H:V) 0.032 0.0097 ft/ft 68.00 cfs 1.73 ft 4.41 f p: 15.41 sf 15.83 f t 16.25 ft 1.55 f t 0.0161 ft/ft 0.79 (flow is Subcritical) Open Channel Flow Module, Version 3.42 (c) 1991 Haestad Methods, Inc. * 37 Brookside Rd m Waterbury, Ct 0670.E.3 lF Ode- K/96ei &ot„tC Z ©fASel Tint Win! 9 c. CA-lcS. 3// f /V el Pe :-L0iJ eAT '� a= 68.7 y 4&,*) N �Ct.✓� � i (5-�e prr'n7to�%1 T9'T � �L t' /O G,�c� r 4z.. N2k sf Iog 5 t�•rOH�� M l+ v 68.7 c �g 2 49r4,4.4 ltSS�ir�J. �v�/fit' C�h tree: 3 s� 0.76' �tiG earl • . d"e 4 z(A% O /S4 ' Circular Channel Analysis & Design Solved with Manning's Equation Open Channel - Uniform flow Worksheet Name: OAKRIDGE Comment: 42" PIPE FLOW Solve For Actual Discharge Given Input Data: Diameter.......... 3.50 ft Slope ............. 0.0041 ft/ft ' Manning's n....... 0.013 Depth......... 3.30 ft Computed Results: Discharge......... 69.29 cfs Velocity.......... 7.37 fps Flow Area......... 9.40 sf Critical Depth.... 2.61 ft Critical Slope.... 0.0058 ft/ft Percent Full...... 94.29 Full Capacity..... 64.42 cfs QMAX @.94D........ 69.30 cfs Froude Number..... 0./t54 (flow is Subcritical) , V5oI 0.17 7 o. 66 O.b& — 2 i5S 5 -rA E. $-2 (,1�IfGa.��S GiG55� ►re�%<c/r7 �u`�I�S 1 Open Channel Flow Module, Version 3.42 (c) 1991 Haestad Methods, Inc. * 37 Brookside Rd * Waterbury, Ct 06708 I 1 �9 y3o�,o� OQKR/DGE _8c.o4r_,2, PN45e/ 7-A4 1 PlPe, PLacJ MH's r 1 C/�-Q 'G✓ K-I Dt� '�D�i S I e'4� t .l .7j�j e��� �J too i No ,) ��/�- T(aL2.,- ' /lia /itJi .....-S Gw.lc ...lrc-r,D-*,.- • { (see P':e-Ae-e�e �ress2lo-ur 3� 1/ 2G� s at su,. n p ,n le ' (set Drin.fsu� -�B'1 ✓PSSuJt.e. ��o-�-� r L tVv 1 11 Circular Channel Analysis & Design Solved with Manning's Equation Open Channel - Uniform flow Worksheet Name: OAKRIDGE Comment: FLOW IN 36" RCP BETWEEN MH'S Solve For Actual Depth Given Input Data: Diameter.......... Slope ............. Manning's n....... Discharge......... Computed Results: Depth ............. Velocity.......... Flow Area......... Critical Depth.... Critical Slope.... Percent Full...... Full Capacity..... QMAX @.94D........ Froude Number..... 3.00 ft 0.0075 ft/ft 0.013 58.00 cfs 2.47 ft 9.31 fps 6.23 sf 2.47 ft 0.0075 ft/ft 82.34 % 57.76 cfs 62.14 cfs 0.99 (flow is Subcritical) Open Channel Flow Module, Version 3.42 (c) 1991 Haestad Methods, Inc. * 37 Brookside Rd * Waterbury, Ct 06708 Pressure Pipe Analysis & Design Circular Pipe Workshmet Name: OAK Comment: PIPE CAPACITY FOR 36" OUTLET CONTROL--MH A~1 Solve For Elevation @ 1 Given Input Data: Pressure @ 1...... 0.00 psi Elevation @ 2-.... 83.85 ft Pressure @ 2...... 0.00 psi Dieoharge..,...... 26032.00 gpm Diameter.......... 36.00 in Length............ 108.00 ft Hazen -Williams C.. 120.00 Computed Results: Elevation @ l..... 84.48 ft Veluoity.......... 8.21 fps Headloas.......... 0.63 ft Energy Grade @ 1.. 85.53 ft Energy Grad* @ 2.. 84,90 ft Friction Slope .... 5.836 ft/1000 ft Open Channel Flow Module, Version 3.42 (c) 1991 Haeotad Methods, Inc. * 37 Brookside Rd * Waterbury, Ct '067OS I .1 I I Pressure Pipe Analysis & Design Circular Pipe Worksheet Name: OAK Comment: UPSTREAM EFFECTS OF STORM SEWER LINE 'A' Solve For Elevation @ 1 Given Input Data: Pressure @ 1...... 0.00 psi Elevation @ 2..... 84.48 ft Pressure @ 2...... 0.00 psi Discharge......... 26032.00 gpm Diameter.......... 36.00 in Length............ 120.00 ft Hazen -Williams C.. 120.00 Computed Results: Elevation @ 1..... 85.18 ft Velocity.......... 8.21 fps Headloss.......... 0.70 ft Energy Grade @ 1.. 86.23 ft Energy Grade @ 2.. 85.S3 ft Friction Slope.... 5.836 ft/1000 ft Open Channel Flow Module. Version 3.42 (c) 1991 Haestad Methods, Inc. * 37 Brookside Rd * Waterbury, Ct 06708 2OC I .1 I .1 11 I 1 5Jr-1&4:�, P.PE :/zox-A -DJ t Er cot LId-114 r*Y 70— MKA / v N-►Z 4Ps -F,p.e kL r1�24- ��Z- t LA Lee 6. 5 �;, Ak jp•� r D,o11��35•� 1 (. ( . 2,5 J TJ /o. 85 'es ("1-4-C.zSJ) Pressure Pipe Analysis & Design Circular Pipe Workshemt Name: OAK Comment: PIPE SIZING FROM LEMAY INLET TO MH A-1 Solve For Elevation @ 1 Given Input Data: Pressure @ 1...... 0.00 psi Elevation @ 2..... 83.85 ft Pressure @ 2...... 0.00 poi Diocharge......�... 4488,00 gpm Diameter.......... 15.00 in Length............ 35.00 ft Hazen -Williams C.. 120.00 Computed Results: Elevation @ 1..... 84.41 ft Volocity,...,..... 8.15 fps Hwadl000....,.,... 0.58 ft Energy Grade @ 1.. 85.44 ft Energy Grade @ 2.. 84.88 ft Friction Slope.... 15.999 ft/1000 ft Open Channel Flow Module, Version 3.42 (c) 1991 H6eotod Methods, Inc. * 37 Brookside Rd * Waterbury, Ct 06708 0 RATIONAL METHOD MASS DIAGRAM REQUIRED 100-YR DETENTION VOLUME PROJECT: Oakridge Block 1, 1st Filing RUN DATE: Project No. 9301.00 07-Jun-93 01:56:24 PM Final Drainage, Sub -basin dl AREA RELEASE RATE C Cf (ac) (0.5 cfs/ac) 0.52 1.25 1.5 0.75 Volume Storage Time i Q Volume Outflow Volume (min) •------------------------------------------------------------ (in/hr) (cfs) (cu ft) (cu ft) (cu ft) 0.00 0.00 0.00 0 6.00 7.00 6.88 2477 270 2207 12.00 6.70 6.59 4743 540 4203 18.00 5.50 5.41 5840 810 5030 24.00 4.70 4.62 6654 1080 5574 30.00 4.17 4.10 7379 1350 6029 36.00 3.72 3.66 7900 1620 6280 42.00 3.40 3.34 8423 1890 6533 48.00 3.10 3.05 8777 2160 6617 54.00 2.82 2.77 8983 2430 6553 60.00 2.60 2.56 9202 2700 6502 66.00 2.40 2.36 9344 2970 6374 72.00 2.22 2.18 9429 3240 6189 78.00 2.10 2.06 9662 3510 6152 84.00 1.97 1.94 9761 3780 5981 90.00 1.88 1.85 9981 4050 5931 96.00 1.75 1.72 9910 4320 5590 102.00 1.68 1.65 10108 4590 5518 108.00 1.60 1.57 10193 4860 5333 114.00 1.50 1.47 10087 5130 4957 120.00 1.43 1.41 10122 5400 4722 126.00 1.38 1.36 10257 5670 4587 132.00 1.30 1.28 10122 5940 4182 138.00 1.26 1.24 10257 6210 4047 144.00 1.21 1.19 10278 6480 3798 150.00 1.19 1.17 10529 6750 3779 156.00 1.15 1.13 10582 7020 3562 162.00 1.12 1.10 10703 7290 3413 168.00 1.10 1.08 10901 7560 3341 174.00 1.08 1.06 11085 7830 3255 180.00 1.05 1.03 11149 8100 3049 ' RATIONAL METHOD MASS DIAGRAM REQUIRED 100-YR DETENTION VOLUME PROJECT: Oakridge Block 1, 1st Filing RUN DATE: Project No. 9301.00 07-Jun-93 02:00:03 PM Final Drainage, Sub -basin d2 AREA RELEASE RATE C Cf (ac) (0.5 cfs/ac) ' -------- --------- 0.76 ------------ 1.25 2.74 ------------- 1.37 Volume Storage ' Time i Q Volume Outflow Volume (min) --------------------------------------------------------------- (in/hr) (cfs) (cu ft) (cu ft) (cu ft) 0.00 0.00 0.00 0.00 6.00 7.00 18.22 6,559.56 493.20 6,066.36 12.00 6.70 17.44 12,556.87 986.40 11,570.47 ' 18.00 5.50 14.32 15,461.82 1,479.60 13,982.22 24.00 4.70 12.23 17,617.10 1,972.80 15,644.30 1 30.00 36.00 4.17 3.72 10.85 9.68 19,538.12 20,915.63 2,466.00 2,959.20 17,072.12 17,956.43 42.00 3.40 8.85 22,302.50 3,452.40 18,850.10 48.00 3.10 8.07 23,239.58 3,945.60 19,293.98 ' 54.00 2.82 7.34 23,783.09 4,438.80 19,344.29 60.00 2.60 6.77 24,364.08 4,932.00 19,432.08 66.00 2.40 6.25 24,738.91 5,425.20 19,313.71 72.00 2.22 5.78 24,963.81 5,918.40 19,045.41 78.00 2.10 5.47 25,582.28 6,411.60 19,170.68 84.00 1.97 5.13 25,844.67 6,904.80 18,939.87 ' 90.00 96.00 1.88 1.75 4.89 4.56 26,425.66 26,238.24 7,398.00 7,891.20 19,027.66 18,347.04 102.00 1.68 4.37 26,763.00 8,384.40 18,378.60 108.00 1.60 4.16 26,987.90 8,877.60 18,110.30 114.00 1.50 3.90 26,706.78 9,370.80 17,335.98 ' 120.00 1.43 3.72 26,800.49 9,864.00 16,936.49 126.00 1.38 3.59 27,156.58 10,357.20 16,799.38 132.00 138.00 1.30 1.26 3.38 3.28 26,800.49 27,156.58 10,850.40 11,343.60 15,950.09 15,812.98 144.00 1.21 3.15 27,212.80 11,836.80 15,376.00 150.00 1.19 3.10 27,878.13 12,330.00 15,548.13 ' 156.00 1.15 2.99 28,018.69 12,823.20 15,195.49 162.00 1.12 2.92 28,337.30 13,316.40 15,020.90 168.00 1.10 2.86 28,862.06 13,809.60 15,052.46 174.00 1.08 2.81 29,349.35 14,302.80 15,046.55 ' 180.00 1.05 2.73 29,518.02 14,796.00 14,722.02 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 i I 1 f OAKRIDGE, BLOCK 1, FIRST FILING Detention Pond Volume for Pond 'A' V=l/3d(A+B+sgrt(A*B)) Depth Contour Between Sum Elevation Area Contours Volume Volume (ft) (sq ft) (ft) (cu ft) (cu ft) 80.50 0.00 0.00 0.00 0.00 81.00 4,138.00 0.50 689.67 689.67 82.00 5,839.00 1.00 4,964.15 5,653.82 83.00 8,318.00 1.00 7,042.04 12,695.87 84.00 9,948.00 1.00 9,120.85 21,816.72 85.00 12,250.00 1.00 11,079.05 32,895.77 OAKRIDGE, BLOCK 1. FIRST FILING Detention Volume for Pond 'B' V=l/3d(A+B+sgrt(A*B)) Depth Contour Between Sum Elevation Area Contours Volume Volume (ft) (sq ft) (ft) (cu ft) (cu ft) 72.85 0.00 0.00 0.00 0.00 73.00 1,960.00 0.15 98.00 98.00 74.00 7,670.00 1.00 4,502.42 4,600.42 75.00 9,360.00 1.00 8,500.99 13,101.41 76.00 11,180.00 1.00 10,256.53 23,357.95 1 1 1 1 1 1 loe'41, L_P e5 Moedded as d I5d✓r ye 4"K A 12k�L �= CA 1.) 'For FOV.A A , soive Via-, Do ( ref : G� l �.�.. Ref 41 ES;+,a.L, M, 9. c-1Ode bLA Q = o 75 c-�s allow"le release yreA4-e k1SEL) i .67 Ao = �/4 %Z D 7d 4--------r O. (oZ 7T '.dal �i2 Z� %2o 1 7 (Dt 0, 19 Z,6 7 - /? Do 6,1 +„;j VOL." j7 = 0,4o = 4.6it h = (100jr w5at )—(`l2 Do ) -- ( lov E-L 75 9 — 1 /. Qo - 72 . 8 3,I _ '/Z Da Qo_ 7/4P,L C� _ 0. (�OZ 1 / f ' l- 37 ��5 = �c�, �z� 'h/a .1� Z 213z. z )i3• l— �/Z 1 ' IVlo ircG\ AS a k✓o Y�!— Gr-e5fEk GcJ�ir , �: p� 11 Gl : C[r�{ 3/z (7'rom TBcE S-3; �✓aft � �«� J ►v e a, I Sic. A• A z�. 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C. . . .� �tonnnnWWWccW0;WWWcoWWWWcoWWWWW 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 n Ill aloVtcn00Wnnn%0%D%Din'VVMMNNrnWv1-10%0 . . . . . . . . . . . . . . . . . . . . . . . . . . . O ONNNNNNNNNNNNNNNNNC4C41; i1;1;00 nnnnnnnnnnnnnnnnnnnnnnnnnn 3E-. o0000000000000000000000000 w zo000000000000000OOOooO0000 I07�4.-+NMVlntonWo,o.-iNMerintonWo�olnolnolno G4 a •-' rl ri r1 rl rl H 9-1 H e-1 H N N M M V V' In MARCH 1991 6;4 DFGprp1 CDITERIA (23 RAINFALL PERFORMANCE STANDARD EVALUATION PROJECT: STANDARD FORM A COMPLETED BY: 7"pN% DATE: SUBBAgIN ZONE (ac) (ft) ($) (feet) Gil ' M,0D /, 5� 32a I • ZS dZ Mop Z. 1 4 So I' MARCH 1991 8-14 DESIGN CRITERIA ' PROJECT: STANDARD FORM B COMPLETED BY: DATE: 1- 3 Erosion Control C-Factor P-Factor Method Value Value Comment P-. 0 o. 5---- - - _ �WAcics�P�►2�%�G /�i5_ Ao1 I•D d1�4 I.op O.E d2 7 SE�a��� __.�-Flit-.--G.SW._2GuI✓ /Mut1H_ - o.n7--.71 0---� 1r92_.n5wal� 'MAJOR PS SUB AREA d I 4jz BASIN ($) BASIN (Ac) CALCULATIONS 7� 4 d1 leS9 . So 03 Bp s, sPl df = D, 4-7 w� 1 c)-c/ yo.471 Z AA le; ]VA' f). 4d- 1 p MARCH1991 EFFECTIVENESS CALCULATIONS 9-15 DESIGN CRITERIA m�5 raj CONSTRUCTION SEQUENCE ' PROJECT: OAKR/D E 8� 1 i S�%r�.r►y STANDARD FORM C SEQUENCE FOR 19 93 ONLY COMPLETED BY: -r r M DATE: 4�7T 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. ►A43 1 I t 1 a GIuA MONTH iP M41IJ&w TLI I Au� I Sep oGt I I I I I OVERLOT GRADING _ -- WIND EROSION CONTROL Soil Roughening Perimeter Barrier Additional Barriers Vegetative Methods Soil Sealant Other I' tAINFALL EROSION CONTROL j STRUCTURAL: Sediment Trap/Basin Inlet:Filters _ Straw Barriers ' -- - Silt Fence Barriers � Sand Bags j Bare Soil Preparation Contour Furrows Terracing Asphalt/Concrete Paving Other I j VEGETATIVE: j Permanent Seed Planting Mulching/Sealant Temporary Seed.Planting Sod Installation' Nettings/Mats/Blankets I Other i I I I � (TRUCTURES: INSTALLED BY MAINTAINED BY GETATION/MULCHING CONTRACTOR SUBMITTED APPROVED BY CITY OF FORT COLLINS ON 0 MARCH 1991 8-16 DESIGN CRITERIA SCALE'. «omz: (--So STORM SEWER LINE HOME -.3. Ex:n GCE: T 7 vi Not ,4975= r TOPPBDit 4975 r. 1 N-12 �coN.c- DAN 4970 FIS, 4970 4965i- _ 4965 0+00 - 0+50 SCALZU °R "r STORM SEWER LINE "B" 1 I 49801 "°A ° ± 4980 i n c cproE� a i 4975 4975, .Ar emu I� 0 FL3. zn°5[ oEuo. . y 4970; r i4970 D RATE I S4Y« L4965 XEAF aRz: 1•-SOS AVEZ r_s' 14 : 41, ti; * 14965 0+00 0+50 1+00 OF CAPE WATIRMAIN v«SSWG TUN ,N STORM SEWER LINE "D" T 4990 R ,4985 EX'mN` `"° SEE o9u6 SHT 7 ! Y 4975; 1 0+00 ' 0+50 1+00 1 `iLhR QllM 1,13. uYER OF RI~ (DIN 1Y) SECTION AI A POND 'A' INFLOW CHANNEL ur5 -V i r'" r: V—PAN SECTION ORIFII PUTS. — 4990 4985 [LINE 0 Gs] <,,3° R.em P N CC HARMONY ROAD 1 IRS lc�_ rONL) A u"3 or NOTES: ___ 1. PARKING AREA TO HAVE OUTFLOW CURB AND GUTTER, EXCEPT WHERE a CONL�'"" DESIGNATED W/ "I" SYMBOL. "I" TO HAVE INFLOW C&G. o; 2. SEE SOILS REPORT FOR COMPACTION RECOMMENDATIONS. 7r. 3. PAVEMENT PARKING AREAS TO CONSIST OF 3" OF ASPHALT OVER 4" OF AGGREGATE BASE. SEE SOILS 7) - REPORT. LEGEND A TINA —`\I PAIL 11 CHASE 4980 � � — {� . SECTION �� \� SI1EEi 6 0 i]ex< -STORM Stnu TINE 'B'3 `WITS OF SPUR ' I =49 75 �n=e*'OII R7ER CLOTH I 1 FEE. Brc Eu, ranee I I I� ^A FE3. i«v. >.-497277 4ORN SUNNI 'C' ' I POND "A..: Do = 4.8" I POND "B": Do = 4.8" • :GO PER EMERGENCY SAU ' I I 1977' 977' PIPE INVERT I >,.RE,flr'„r;,,.oLENI' —u-a•— SIDE SLdPES _ 4.1 I ET IL S. — PONDS II & "BAN SPILLWAY DETAIL — Nii. POND "If A4 S R 5 EO _j -- EXISTING STORM SEWER PROPOSED STORM SEWER EXISTING STORM DRAINAGE INLET F_ PROPOSED STORM DRAINAGE INLET SWALE W/ TRICKLE PAN FLOW LINE — PROPOSED CONTOUR XISTING CONTOUR =INISH GRADE EF. '"PROS IEO FLOOR B. fa A, IT7 rz"R 2P �L F� OUTFALL CURB SAND GUTTER Ni 2e ; 6 In Y a YR ) YR ry 1 •_1 F" INFLOW VERT. CURB h GUTTER / @ \ avee��NORTH mD EN SCALE. V 40' Rev! sI° B R — ate NORTHERN ENGINEERING SERVICES PF°"`t' 9301 0oP"";Nu;B�, - SCALE: 1' -40' 420 SOLTH HOWES SUITE 108, FT. COLLINS, COLORADO 80521 DESIGNER TPM ._ CHECKED BY: M FJ -. ---- -. -- (303) 221— 158 _ DRAFTSMAN CADD , 993 PREPARED:JAN1 CICS UN NUHI GVLLl1ia, WLV[ 111TLITV PLAN APPROVAL APPROVED CNECNF➢ BYi�_ _ OPENEDB. EPy OAKRIDGE BLOCK ONE P.U.D. FIRST FILING GRADING PLAN