The URL can be used to link to this page

Home My WebLink AboutNOKOMIS SUBDIVISION - FINAL - 8-94A - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORTSTEWARTSSOCIATES Consulting Engineers and Surveyors. March 31, 1994 Mr. Basil Hamdan Storm Water Utility City of Fort Collins P.O. Box '580 ' Fort Collins, Colorado 80522 Dear Basil: The following is the erosion control cost estimate for Nokomis Subdivision: 1. Straw Bale Dikes — 3 @ 100.00 $300.00 2. Rock Filters — 2 @ 100.00 200.00 3. Silt Fence — 220 L.F. @ 2.00 440.00 Total $940.00 Reseeding 5.05 Acres @ 0.0149/S.F. $3278.00 The amount of deposit for erosioncontrol shall be 150% of $3278.00 which is $4916.50. If you have any questions regarding this cost estimate, please call. Sincerely, Richard A. Rutherford, P.E. & L.S. President jrr James H. Stewart and Associates, Inc. 103 S. Meldrum Street P.O. Box 429 Ft. Collins, CO 80522 303/482-9331 Fax 303/482-9382 -EFFECTIVENESS CALCULATIONS ----------------------------------------- 7---------------------------- PROJECT: V o k o m if ,fv a D1v tj10 A) - Co, b"No., STANDARD FORM B COMPLETED BY: e A e- DATE: MAJOR BASIN I Erosion Control C-Factor P-Factor Method Value Value Comment ---------------------------------------------------------- PS a ,a 7G•9% SUB BASIN ---------------------------------------------------- AREA (Ac) CALCULATIONS ------ -----------/-�-------------------------------- 6.52.At. Bgr2E copPOUND 0, l9Ar. (Jv��tTUGF35p 0.33At. W TD C = (0. 19 X 1.0) + (6.33 n0. 06) s 2 0.4-0 uht> p = 0.80 X0,50 = 0,40 E FF= C l — (0.40 X0,40)Jh/00= 84,0 0/0 0vER-A(L, Ecr6-c%)f/E:.tl6SS = (2•03 k 063) 1(i,4axo•fiCf 1 (0-SZx 0.84� /� 'Z ---------------------------------------------------------------------- DI/SF-B:1989 EFFECTIVENESS CALCULATIONS --------------------_-------------------------------------------------- PROJECT: No Ico mi-r fu a DAv/,A/ov STANDARD FORM B COMPLETED BY: ,e A 9. DATE: Ai Erosion Control C-Factor P-Factor Method Value Value Comment ---------------------------------------------------------- •9A26 G)Inov/vD /," TcMP,SEED eMv(cN 0,06 S-rKAw BAL61 Rock- /,rp 0160 FAL -rEcj /. d•o 0,80 ASPHALT bCONC. 0,01 UNDI.1Tvlze6 a. 0,0` S /L -r F6A)cr. ---------------------------------------------------------------------- 1, oo ry MAJORI PS SUB AREA BASIN (%)• BASIN (Ac) CALCULATIONS ----- ------ -------- -.-- -------------------------------------- 76.970 'A4 AZSAc. •D A 26 GRO,;rJt, — 0.4o Ac. VAJb/STUCBGD - 6,8S Ac WTD C = (D, 90 x /•o) +(p.gSx 0,04) 0.36 tuTD 1' = O, 0v x D,5o 0,4 6 EFF = L,l-(0,36 x0.40) Jx/o0 - SS•6-/ %� 9'/oi ,•$u 12.o3Ac.l aAeE GeUUND - J•S7�c FouN.D AT/oNs - o.Z/ Ac• ,.c l• "At. z,03 o,gr>o %D = D•60x0•s0 = 0,4p EfF =C1—%•8ti�xo•40)]x/oa BAI« �ji �pUNrj — D•Q-IAc• 0,vDrsrua-6aD W-rD C = ((,cjl K l•O) t (/•03x 0106) = 033 tj j� = 0. 8 0 x 0, so = 0. ¢0 ------------------------------------------ HOI/SF-B:1989 RAINFALL PERFORMANCE STANDARD EVALUATION . --------------------------------------------------------------------- PROJECT: A/okOMIJ S'u$D/✓/J/ON STANDARD FORM A COMPLETED. --------------------------------------------------------------------- BY: kA DATE: StArm. 3,/9lp, DEVELOPED ERODIBILITYI Asb ! Lsb I Ssb Lb Sb I PS SUBBASIN ZONE I (ac) I (ft) I W .`(feet) I (o) I ( ) � --- MODE2ATB ZSA/.I ------- S80 I ------- o-8L/,I --=---- ------- I g" /40DG?-A>6 I Z.03AJ s0' I p.9Z% I I I C M OOVAAM I' / ¢¢Ac.1 G IC)' I o,b?, I I m pD6RATE 0.S2/I�.I //0' I /,ov I --------------------------------------------------------------------- DI/SF-A:1989 CONSTRUCTION SEQUENCE PROJECT: Noko Mar duBpiyi./'/e ,y STANDARD FORM C SEQUENCE. FOR 19 94- ONLY COMPLETED BY: P— 4,0— DATE: t4AP— 311?94 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 Qngineer. YEAR MONTH OVERLOT GRADING WIND EROSION CONTROL Soil Roughing Perimeter Barrier Additional Barriers Vegetative Methods Soil Sealant Other F vvAlDAT/oN5 $!L-r F A'CF`.` RAINFALL EROSION CONTROL STRUCTURAL: Sediment Trap/Basin Inlet Filters Straw Barriers Silt Fence Barriers Sand Bags Bare Soil Preparation Contour Furrows Terracing Asphalt/Concrete Paving Other CONG. PAAI - S/CrT FENcc- VEGETATIVE: Permanent Seed Planting Mulching/Sealant Temporary Seed Planting Sod Installation Nettinas/Mats/Blankets Other STRUCTURES: INSTALLED BY C I F IM I R ------------------ VEGETATION/MULCHING CONTRACTOR DATE SUBMITTED HDI/SF-C:1989 ITITIAIs --------- ---- lol/uID! ---- ---- ---- ----I I I I I I I i I I I I � I I I I � I I � I I 1 ----- -----------------------------� ' 1 I I I I I I I MAINTAINED BY APPROVED BY CITY OF FORT COLLINS ON JANUA 2,Y 199 L 8-20 DESIGN CRITZRI;'. AREA"8 (off drowin AREA 4*6 I6 CONIFER ST. N SCALE: Iu_ 800' 0 ° 19.1 ° IAc-Ftl a 'I I a i W AREA "2 AREA "OA J 130 Z CONIFER ST. 105 220 223 1 9 5.B Ac-Ft ? IOI f 74 9.5 :: .. 233 20 Ac-Ft ZEE) I Ac-Ft 200 210:. aeterly Release 214 AREA 120 Point "5 AREA "OB i N ape �... Ac—Fti GP z - I \�� Southerly Releaes Point NOTES: 1) SHAPE a SURFACE AREA OF PONDS APPROXIMATE ONLY. I2) POND NUMBERS ARE SAME AS BASIN NUMBERS. LEGEND BASIN . BOUNDARY STORM SEWER OR CULVERTS 123 OPEN CHANNEL W/CONVEYANCE CODE USED IN TABLE I. C••.� DETENTION PONDS e c+I TITLE EVERGREEN PARK FIGURE c °�`�"°5V` FINAL DRAINAGE PATTERN 2 No Text FEBRUARY1994 Manning's Equation for the Theoretical Capacity of Non-Symetrical Triangular Section 0.200 =Side Slope 1 0.060 = Manning's (n) 0.200 =Side Slope 2 This Section 0.200 =Side Slope 1 0.060 = Manning's (n) 0.200 =Side Slope 2 This Section 0.01 = Channel Slope III TYPICAL 2-indeep 0.004 =Channel Slope TYPICAL 2-in deep Flow Depth Intercept Area 1 Intercept Area 2 Total Discharge Intercept Area 1 Intercept Area 2 Total Discharge (ft/ft) (ft from CL) (sq/ft) (ft from CL) (sq/ft) This Section (cfs) (ft from CL) (sq/ft) (ft from CL) (sq/ft) - This Section (cfs, 0.50 2.50 0.63 2.50 0.63 1.21 2.50 0.63 2.50 0.63 0.77 1� 97 3, 00: ��:iio .90 i3.00 ........ :: -.,- 0-90 0.70 3.50 1.231 3.50 1.23 2.97 3.50 1.23 3.50 1.23 1.88 0..80 4. 00 1.60 4.00 1.60 .:-4 25 4.00; 1.60 4.00 1 60 ... 269 0.90 4.50 2.03 4.50 2.03 5.61 4.50 2.03 4.50 2.03 3.68 1:.00: `; SOD 2.'50, 5:00 ' 2.50 '' .70 5.0G ... 5.00 . 50 .. ....... .87 1.10 5.50 3.03 5.50 3.03 9.93 5.50 3.03 5.50 3.03 6.28 1: 20: :.::-...6;00 3.60 :3 601 AM: 112oU 6.0 G::-:�z::-:-,3.6G .0 ..6. 0 3 M 7*92 1.30 6.50 4.22 6.50 4.221 15.50 6.50 4.22 6.50 4.22 9.80 1.40] 00 4 90] '00 ;�:::7771&891 7777�, 9 11.94 .. ... ............. NOTE: The manninq's (n) Value is between the typical All 12' easements are 12'for drai#nge pans HD" �SDWN 15CKLC5-r FNN5 CC LJ, C,-fe 5)A �Ic4 -- I I ACA I CliF 5 N%li7H r P �I -�i SlPEF-WAK w«'u --�I DATA CONSTANTS Type i Location NAKOMIS CT. / RESIDENTIAL FLOWLINE WIDTH (ft) CROSS SLOPE (ft)l I STREET SLOPE (ft) I YARD - SLOPE (ft) WALK WIDTH (ft) DEPTH @ I CURB F.L. CURB HEIGHT (ft) CROWN ELEV. REDUCT'N FACTOR 36.001 0.02001 0.00401 0.020 5.001 ME 0.50 100.09 0.80 CALCULATED CONSTANTS WETTED PERIMETER WEIGHT'D IMANNINGS1 I TOP WIDTH AREA OF FLOW 97.011 0.02581 96.001 41.98 CALCULATED HYDRAULICS THEO. ALLOW CAPACITY cfs CAPACITY WATER ELEV. VELOCITY s 87.511 70.011 100.501 0.72 No Text DRAINAGE CRIT lIA MANUAL RUNOFF C • S°76 =7 N1 = l.S �s 50 30 1— 20 z w U lr w °' 10 z W (L O 5 U) w cc 3 0 U 2 W F- a t3 1 MON MFA FAA VWAA .2 .3 .5 1 1 2' 3 5 10 20 VELOCITY IN FEET PER SECOND FIGURE 3-2. ESTIMATE OF AVERAGE FLOW VELOCITY FOR I USE WITH . THE RATIONAL FORMULA. *MOST FREQUENTLY OCCURRING "UNDEVELOPED" LAND SURFACES IN THE DENVER REGION. REFERENCE: "Urban Hydrology For Small Watersheds" Technical Release No. 55, USDA, SCS Jan. 1975. 5 -1-84 URBAN DRAINAGE & FLOOD CONTROL DISTRICT DEVELOPED RUNOFF COMPUTATIONS FROM RATIONAL METHOD Q = C x Cf x I x A . ......... SUBBASIN:TO.C.:,0wv D. Pnt. Slope qo C Cf Length feet(min.) Overt Tc Vel.Chan (ft/sec.) Tc Chan. (min.) Tc Total (min.) COMMENTS 1.001 0.75 200.00 9.31 Tc (100) 1.001 0.00 1 1.501 0.0 9.13:1 LNGST. OVERL.+CHANNEL 0.60 = Runoff C 1.00 = Cf 2,10 1.25 =Cf 100 D. Pnt. Area (acres) C *Cf I (2yr.) (in/hr) 1 (1 Oyr.) (in/hr) 1 (1 00yr.) Q n/h r) Basin Q f Comb. Q I : (cfs) COMMENTS 1.31 0.60 2.30 _(cfs) 1.81 .811 2 yr. runoff 0.60 4.10 3.22 :.3121 0 yr. runoff 0.75 6.60 6.48 .--6.5jL— ii-0-0 yr. runoff 0.60 = C 1.00 =Cf 2,10 1.25 =Cf(100) DEVELOPED RUNOFF COMPUTATIONS FROM RATIONAL METHOD Q = C x Cf x I x A SUBBASIN :...:.O.C.:"100 r D. Pnt. Slope C* Cf Lengt ver c Va. an Tc Chan. Tc Total COMMENTS (feet) (min.) (tt/sec.) (min.) Orlin.) 2.001 0.751 80.001 4.61 Tc (100) - - ----- -0-65-F- 1 595.001 1 1.60 6.20 ......... .108JINGST OVERI.+CHANNEL 0.60 = Runoff C 1.00 = Cf 2,10 1.25 =Cf 100 D. Pnt. Area (acres) C Cf I (2yr.) in/hr) I (10yr.) (in/hr) I (100yr.) (in/hr) Basin Q cf Comb. Q COMMENTS A 1.251 0.601 2.701 2 03 2 yr. runoff 1 0.601 5.00 2.25 25MO r .. -.2.31 10 yr. runoff 10 r 1 0.751 6.56 100 100 r. runoff 0.60 C 1.00 =Cf 2,10 1.25 =Cf 100 1*. ��* A . - . ' . - SUBBASIN T.O:C-'100 r D. Pnt. Slope C*Cf I Length I Overt- Tc Vel.Chan Tc Chan. Tc Total COMMENTS (%) I (feet) (min.) (ft/sec.) (min.) (min.) B 77 2.031 0.751 50.001 3-7 Tc (100) 0.601 1 680.00 1.60 7.1 .. .... r:.: 7. LNGST. OVERL.+CHANNEL 0.60 = Runoff C 1.00 = Cf 2,10 1.25 =Cf 100 D. Pnt. Area (acres) C*Cf I (2yr.) (in/hr) I (10yr.) in/hr) I (100yr.) (in/hr)_ Basin 0 (cfs) Comb. 0 (cfs) COMMENTS 2.03 0.601 2.401 2.92 2.911 2 yr. runoff 0.601 1 4.20 5.12 L1L_ 10 yr. runoff 0.75 1 1 10.51 05 11 100 yr. runoff 0.60 = C 1.00 =Cf 2,10 1.25 =Cf(100) :SUBBASIN '....T. 0 D. Pnt. Slope C Cf Length (feet) Overt- Tc (min.) Vel.Chan (ft/sec.) Tc Chan. (min.) Tc Total (min.) COMMENTS 2.00 0.751 80.001 4.61 1 Tc 100 () 0.90 1 600.001 2.501 4.0 i6�GST. OVERL. +CHANNEL 0.60 = Runoff C 1.00 = Cf 2,10 1.25 =Cf 100 D. Pnt. Area (acres) C Cf I (2yr.) (in/hr) I (10yr.) (in/hr) I (100yr.) (in/hr) Basin Q cf Comb.. i (cfs) COMMENTS C:::- 1.44 0.60 2.80 2.42 j f ... 2.411 2 yr. runoff 0.60 5.00 4.32jr77 774.3 11 10_yr. runoff 0.75 7.00 7.56 11 7.611 100 yr. runoff 0.60 = C 1.00 =Cf 2,10 1.25 =Cf(100) 4.72 = Area(ac) tnis page DATE: MARCH 1994 DEVELOPED RUNOFF COMPUTATIONS FOR 2/10/100 YR. STORMS NAKOMIS SUBDIVISION FOR: U.S.A.G. CAPITAL AND LEASING BY: Stewart & Associates GENERAL NOTES: Velocity In a Channel per FIGURE 3-2 If C x Cf > = 1 then C x Cf = 1 (constants listed below) For design of the developed site runoff quantities Tc(l 00) was the basis for design B:\NAKOMRO.wk3 HISTORIC RUNOFF COMPUTATIONS FROM RATIONAL METHOD Q = C x Cf x I x A .SUBBASIN:::..T.O.C..:.:.(1004);::::::::: D. Pnt. Slope C * Cf Length (feet) Overt- To (min.) Vel.Chan (ft/sec.) To Chan. (min.) To Total (min.) COMMENTS 1.001 0.251 360.001 30.2 To (100) 1.00 0.001 1.50 0.0 :4*30.2 LNGST.OVERL.+CHANNEL 0.20 = Runoff C 1.00 = Cf 2,10 1.25 =Cf 100 D. Pnt. Area (acres C * Cf I (2yr.) Qn/hr) I (10yr.) (in/hr) I (100yr.) Basin Q cfS Comb. Q (cfs) COMMENTS ... 3.521 0.201 1.481 1.0411: 2 yr. runoff 1 0.201 1 2,601 1.83 10 yr. runoff 1 0.251 1 1 4.16 3.66 3:711 100 yr. runoff 0.20 = C 1.00 =Cf 2,10 1.25 =Cf 100 ILLLLLA iSUBBASIN:::*.::T.O.0::.,,.,(100yr),I.i... D. Pnt. Slope N C*Cf Length (feet) Overt- To (min.) Vel.Chan (ft/sec.) To Chan. (min.) To Total (min.) COMMENTS 1.001 0.25 360.00 30.2 To (100) 1.001 0.00 0.501 0.00 .-.30.2 LNGST. OVERL.+CHANNEL 0.20 = Runoff C 1.00 = Cf 2,10 1.25 =Cf 100 D. Pnt. Area (acres) C Cf I (2yr.) (in/hr) 1 (1 Oyr.) (in/hr) 1(100y.) (in/hr) !BlasinQ CfSL_ Comb. Q cfs COMMENTS 3.511 0.20 1.48 1.04F7T777T0j 2 yr. runoff 0.20 2.60 1.83 10 yr. runoff 0.25 4.16 - I.. I.. " I a L L-- 100 yr. runoff 0.20 C 1.00 =Cf 2,10 1.25 =Cf(100) 1.UJ = FrOjeCt Area (act 12-YEAR HISTORIC 1 2.08 OTALDEVELOPED.. ..RUNOFF...*......*..:.:.,...,:. 9.21 2 yr. runoff 14.91 10 yr. runoff 31.11 100 yr. runoff 6.03 = Total project area(ac) NAKOMIS COURT PAN. 3.51 2 y.. runoff 4.81 10 yr. runoff 11.81 100 yr. runoff Basins A + B(1/2) q NAKOMIS:.COURT.STREET. FLOW ...... E5 2 yr. runoff 2.61 10 yr. runoff 5.31 100 yr. runoff Basins B(1/2) EACH SIDE HISTORIC. FLOW 10 ynrunoff . 73 1 1100 YKrunoff TOTAL SITE HYDROLOGIC SUMMARY NAKOMIS SUBDIVISION .. ... .. PAN NORTWBACIKLOT �.O 2 yr. runoff 2.31 10 yr. runoff 6.61 100 yr. runoff Basins A SOUTH:BACKLOT ... ......... .. ................ 2.41 2 yr. runoff 4.31 10 yr. runoff 7.61 100 yr. runoff Basin C FLOW TO OUTFALL:CHANNEL#223.. .81 2 yr. runoff 3.21 10 yr. runoff 6.51 100 yr. runoff Basin 0 Nokomis Subdivision Page 2 The site has good ground cover on most of the site. There is some existing landscaping on the site, which will be retained as much as possible. Nokomis Court will be rough cut and the utilities constructed thereafter. The area from the front of the proposed houses to the rear concrete pan will not be disturbed until the house is constructed. Straw bale barriers and rock filters will be placed at discharge points. The storm water runoff calculations and the preliminary grading and drainage plan are enclosed as a part of this report. If you have any questions regarding this report, please call. To the best of my knowledge, this report and the design of this drainage system are in compliance with the current City of Fort Collins criteria. Sincerely, Richard A. Rutherford, PT & L.S. President '��pnunHry+r RUry�•,,, j r r .�P��1STEjQ�v9.��p enclosures ' • r .r .•o C— STEWARF&kSSOCIATES Consulting Engineers and Surveyors March 31, 1994 Mr, Basil Hamdan Storm Water Utility City of Fort Collins P.O. Box 580 Fort Collins, Colorado 80522 Dear Basil: The following is the final storm drainage report for Nokomis Subdivision, Fort Collins, Colorado. The site contains 5.20 net acres and 5.48 gross acres, including the west half of Redwood Street. It is located on the west side of Redwood Street approximately 300 feet north of Conifer Street in the Northwest I of Section 1, Township 7 North, Range 69 West of the 6th P.M. The site is in the Evergreen Park Drainage Basin. It is bounded on the east by Redwood Street, on the south by the New. Beginnings facility that has been recently closed, on the west by existing industrial uses in Evergreen Park and on the north by the proposed Greenbriar Village. The site slopes from west to east at approxi.mately 0.4% grade. It is proposed to subdivide the site into 21 single—family detached residential lots. The site will be divided into four developed sub —basins. The existing Evergreen Park Detention Pond 130, as shown on the Evergreen Park Basin Major Storm Drainage Study proposed by Engineering Professionals, Inc. and dated February 1981, is adjacent to this site at the northwest corner of the proposed subdivision. Also, the outfall channel from Pond 130 is along the west boundary of the subdivision. It is proposed to carry the runoff, undetained, from Sub —Basins "A", "B" and "C" in the curb and gutter of Nokomis Court and in concrete pans along the north and south boundary lines to Redwood Street. The runoff would then flow southerly in the west gutter of Redwood Street to an existing 5—foot curb inlet and existing area inlet at the northwestcorner of Redwood Street and Conifer Street. Existing storm drains then would carry the runoff to existing Detention Pond 120. Sub —Basin "D" is the rear yards of Lots 10 through 13 which drain westto the existing Outfall Channel No. 223. Channel No. 223 flows south across Conifer Street to existing Detention Pond No. 150. James H. Stewart and Associates, Inc. 103 S. Meldrum Street P.O. Box 429 Ft. Collins, CO 80522 303/482-9331 Fax 303/482-9382 FINAL DRAINAGE REPORT FOR NOKOMIS SUBDIVISION MARCH 31, 1994 STEWART & ASSOCIATES, INC. 103 SOUTH MELDRUM-STREET FORT COLLINS, COLORADO 80521 303/482-9331