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HomeMy WebLinkAboutDrainage Reports - 09/10/1997 (3)0 Final Apprlvad.R�pod FINAL DRAINAGE REPORT FOR LOT 5, REPLAT BLOCK 2, UPLAND'S PROSPECT BUSINESS PARK P.U.D. SPRING CREEK DRAINAGE BASIN PREPARED FOR ADVANCED DRAINAGE SYSTEMS AUGUST 279 1997 PREPARED BY STEWART & ASSOCIATES, INC. 103 SOUTH MELDRUM STREET FORT COLLINS, COLORADO 80521 970/482-9331 ' Table of Contents 1-2 Report ' 3 Vicinity Map 4-5 Runoff Calculations ' 6-8 Detention Pond ' 9-12 Erosion Control Pocket Grading, Drainage Plan 1 t 1 1 1 1 1 �1� STEWART&&SSOCIATES ' Consulting Engineers and Surveyors ' August 27, 1997 Mr. Basil Hamdan Storm Water Utility City of Fort Collins P.O. Box 580 ' Fort Collins, CO 80522 Dear Basil, The following is the final drainage report for Lot 5, Block 2, Replat ofUpland's Prospect Business Park P.U.D., Fort Collins, Colorado. ' The site is in the Spring Creek Drainage Basin and is at the Northwest end of Academy Court. ' It lies between the Burlington Northern Railroad and the Union Pacific Railroad. Lot 5 contains 7.0410 acres. ' There was a Drainage Report and a Grading Plan for a part of Lot 5 that was approved February 27, 1995. That plan had a 3.0 acre lot for outdoor storage. There were no buildings planned in that site plan. The grading plan included a detention pond with an outlet to the Northeast that required and offsite drainage easement prior to any issuance of a building permit. It was not possible to obtain the easement, therefore the lot was not built on. ' In December 1996, Mr. Charles Lockman had the lot graded in a different drainage scheme. Overlot grading was done to have the lot slope Southwesterly to the property line along the Union Pacific Railroad and then Southeasterly in a swale a long the Union Pacific Railroad ' property line to the most Southerly comer of Lot 5. A berm was created along the lot line common to Lots 4 and 5 which created a detention pond in Lot 5. A 15 inch diameter N-12 A.D.S. pipe was laid under the berm to drain the stormwater runoff from Lot 5 to Lot 4. Lot 4 was regraded in the same manner as Lot 5 and a swale along the railroad property line was continued Southeasterly until it discharges into the existing 4 foot wide concrete channel along ' the Southerly line of Lot 4. A drainage easement across Lot 4 is enclosed. After the grading was completed, Mr. Lockman had recycled asphalt placed on 4.19 acres of ' Lot 5. He has leased the property to Advanced Drainage Systems, Inc. for a small office and outdoor storage of drainage pipe. A request for an Administrative Change for the P.U.D. was submitted and subsequently denied due to more recycled asphalt being placed on the lot with no ' permission given by the City of Fort Collins. This drainage report and the grading and drainage plan are being submitted to acquire approval from the Storm Water Utility at this time. ' James H. Stewart and Associates, Inc. 103 S. Meldrum Street P.O. Box 429 ' Ft. Collins, CO 80522 970/482-9331 Fax 970/482-9382 1 (2) The runoff calculations are for the 4.17 acres of recycled asphalt, 0.02 acres of office and the ' remaining 2.85 acres of bare ground and weeds in Lot 5. The most Northwesterly 0.94 acres of Lot 5 was not regraded. Top soil, from the area that was regraded, was stockpiled on a small part of the 0.94 acres. The 0.94 acres slopes Southerly to the existing borrow ditch along the Union ' Pacific Railroad and then Southeasterly to the detention pond at the Southeast end of Lot 5. The ground cover of this area is heavy weeds. There is no drainage trapped in that end of Lot 5. The ' calculations also include the runoff from half of the Union Pacific Railroad right-of-way. The historic runoff rate from Lot 5 in the two year storm is 2.08 c.£ s. The 100-year runoff ' rate from the developed site is 15.96 c.£s. The required detention for the difference between the two rates of runoff is 45,948 cubic feet. 47,638 cubic feet of detention volume is being provided in the proposed detention pond. A headwall with a restriction plate with a 6'h inch by 6'/s inch opening will replace the Northwesterly flared end section on the outlet pipe. The high water line of the pond will be 4932.9 and the top of the berm will be 4933.9 to ' provide one foot of freeboard. A spillway will be provided at the driveway at elevation 4932.9. It will spill into Academy Court and flow to existing curb inlets on both sides of the street near the corner common to Lots 3 and 4. The office building will have a finish floor at elevation of 4934.4 ' which will provide 1.5 feet of freeboard. EROSION CONTROL: The site is in the moderate wind erodibility zone and in the moderate rainfall erodibility zone. A gravel sediment trap will be placed at the outlet from the detention pond. As stated above, the recycled asphalt has already been placed on 4.19 acres. The remaining 2.85 acres is bare ground or undisturbed ground with weed cover. The only new disturbance will be the construction of the foundation for the office building and the trenching for utility services into the building. The office building will be a manufactured building that will be placed very quickly. The runoff calculations, mass diagram, erosion control calculations and the grading and ' drainage plan are included as a part of this report. This drainage report and the design of the drainage system were made in substantial compliance with the City of Fort Collins Storm Drainage Design Criteria and Construction Standards. Ifyou have any question during your review of this report, please call. Sincerely, ' Richard A Rutherford, P.E. & L. S.'k 5 028 rrc 1 7� ,=I" ■, �rT - vo-I. ri 4,m _ _ grill IT i�f'lJ Nl1 n I I I I I I I I 11 11 U 11 I I I I I I I STEWART&ASSOCIATES Consulting Engineers and Surveyors 103 S. MELDRUM, FORT COLLINS, CO 80521 PH. 482-9331 FAX 482-9382 By: F" 4, 0— — Date: L /Z7/077 Client: A r,> r o DZA,'AIA Galy.LT, Sheet No. Hof W L-L 7-5� 7- -C. - J-1 �Z Zb- air —Ak Z'4- -L -. -e Vat 6=7 (e:; A4 ZY/e f io An S. Nw—q.lob 4e ZS x 1 5 STEWARr&&SSOCIATES 103 S. MELDRUM, FORT COLLINS, CO 80521 Consulting Engineers and Surveyors PH. 482-9331 FAX 482-9382 By: p_.AP-. Date: 6 Client:ApyAAler.C2 -DeAw,4&&.r�lrs SheetNo. of — Project:/ n 7- Si )z j5- p LA -r F3 1- 0 r, A-- 7- 1 UPLAUm's Ale*- Pa��. Subject: T)i=-- v t- t) pr-- p JToem CAZ-CL1e,,q7-1QA1( -FA &lilt 'rp rsc"'yc�.D-A -4-17 Ac 0 p- G- -r 1.4 71 �d .8 S --j-1 L :L. z 0A OJ- 06 0. -6-o 4.9 7 -7 r- So � .7-5 r-7/mc- .4-,F-r1Sfr- M IV. LaFS,-- lD&V.i i7l),,Cv, 0 0- e-- 0 96/7--C- 1 I STEWART&kSSOCIATES 103 S. MELDRUM, FORT COLLINS, CO 80521 Consulting Engineers and Surveyors482-9331 FAX 482-9382 By: e, A-. Date: (.,L?,7197 Client: A r)v,4 Ale ac z>Dp--4/Aj4e-& 4xzsm-s Sheet No. (g of Project: ept-A -r B 1,o nk Z, 1-)PZA AJDS PP, 0SP96r B VILVE.Cr F4P—k F,! Subject: M R. r_r /A r. te A AA IV U.M- __c VIO-I-IuA� O-J, 0 W.1 —7---Lz5xV. 46X-1-2 JZO F7 A-3. 7 00 7 0 ' _ _ 2, 3 __ T _ __%3 o Z �S4; �84 _r-! i73 4-71919 -4 cy, n' -4-,Sj-6 36 12,0 1 0'. 3272 4. -7- z -4 --- 4-- 7 t 1 4 -7- A) i i+ I -7- At AL f IF I) iti 7A' 30 40 so &4 7() 80 q,) (io 160 -7-7 M a 141 ot.J. STEWART&JkSSOCIATES Consulting Engineers and Surveyors 103 S. MELDRUM, FORT COLLINS, CO 80521 PH. 482-9331 FAX 482-9382 By: P 4 ie, — Date: 41z.71q? Client: ApyAvcrap SheetNo. -7—Of— Project: Ln:z S,- R,5 PLATRcock- 4 ljr;�-s Bysilycgs--r A4.e& P. Zz Subject: L, F47: DRr- )Ir-eg. CALruL.,!2t-r1QA1-S. It !LLow 'A - I J I I it I -FT q X-3 t 7 FT. Sco j xt -4- _LLi Ul L- 1-7 (8) EMERGENCY SPILLWAY DESIGN Weir Equation Q = C L (H) ^ 3/2 Q (cfs), C (weir coefficient), L (crest length, feet), H (energy head, feet) See Table 704 in this Report for C factors 24 = Weir Length L in feet 3.1 = Weir Coefficient Weir Shape Broadcrested Design Flow 33.26 (cfs) Depth of flow (ft) Flow Over Weir cfs 0.50 26.30 0.55 30.35 0.56 31.18 0.57 32.02 0.58 32.86 0.591 33.72 0.60 34.58 0.70 43.57 0.80 53.24 1.00 74.40 0100 maximum= 33.26 cfs Crest 4932.8 0) ' CONSTRUCTION SEQUENCE PROJECT: / or Llt_ _- kEALnr 110.1-auef PjearP6CT BariNeu peek P(I V. STANDARD FORM C SEQUENCE. FOR 19 d? 7 ONLY COMPLETED BY: ,Q 4.o, DATE: J4it7,7,i447 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. 19s9 YEAR ' ' ----------------------MONTH OVERLOT GRADING WIND EROSION CONTROL Soil Roughing ' Perimeter Barrier Additional Barriers Vegetative Methods Soil Sealant ' Other ' 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 VEGETATIVE: Permanent Seed Planting Mulching/Sealant Temporary Seed Planting Sod Installation Nettings/Mats/B1'ankets Other ----------------------------- STRUCTURES: INSTALLED BY llnzlllnall Lw Y1 ' VEGETATION/MULCHING CONTRACTOR DATE SUBMITTED APPROVED BY CITY OF FORT COLLINS ON ' HOI/SF-C:1989 .1 Ai D- JANUARY 1991 8-20 DESIGN CRITERIA C61 RAINFALL PERFORMANCE STANDARD EVALUATION ------------------- ------------------------------------------------- PROJECT: LorS, Bt-.tc 2, Opt-4uos ,STANDARD FORM A COMPLETED BY: A DATE: ,,,,� z , If ------------------------------------------------------ DEVELOPEDIERODIBILITY1 Asb Lsb I Ssb I Lb I Sb I PS SUBBASIN I ZONE I (ac) I (ft) I (%) .1(feet) I (%) I () LD-TS I MonsRATEi 7.0¢AJ )91q' 1 19 i9' I o.s% 1 ----------------------- DI/SF-A:1939 EFFECTIVENESS CALCULATIONS PROJECT: L oT S, B Lk 2, REPLAT OPLAAror 50SAVErr PAjek P- a- D. STANDARD FORM B COMPLETED BY: A? A e- DATE: Tuna 2 /qq Erosion Control C-Factor P-Factor Method Value . Value Comment B ARG Gleou,v,= /. 0 /. o 21 &.T Ac' ROCYCL6D A. -pI444 d,oS b o 4.19 Ac-, .S6Diu16N-r TRAP /.0 O.SO RC-seETDING o.qs b a MAJOR PS I SUB I AREA BASIN ($) BASIN (Ac) CALCULATIONS Lo7S 7z,,z... — I 7,04Ac wry c- Ci,o x z •Ss) t 7,0 (o.os x 9-,re) 3 ok_ 0.43 W -r c P. = 0 . so ¢3x 0.So)J K /Do 0 lc 78.5 72.2 1 MARCH 1991 DESIGN CRITERIA ►z 1 1 1 1 1 1 1 1 1 1 1 1 1 1 STEWAU&kSSOCWES Consulting Engineers and Surveyors August 27, 1997 Mr. Basil Hamdan Storm Water Utility City of Fort Collins P.O. Box 580 Fort Collins, CO 80522 Dear Basil, The following is the erosion control cost estimated for Lot 5, Replat of Block 2, Upland's Prospect Business Park P.U.D. 1. Sediment Trap 1 @ $150 $ 150.00 2. Straw Bale Dikes 2 @ $75 $ 150.00 3 Reseed 1.93 Acres @ $1300/ Ac. $2,509.00 The escrow will be 1.5 x $2509 = $3764 If you have any questions regarding this estimate, please call - Sincerely, Gz,lt.,u,.c, U. CRZ6� -,c Richard A. Rutherford, P.E. & L.S. rrc James H. Stewart and Associates, Inc. 103 S. Meldrum Street P.O. Box 429 Ft. Collins, CO 80522 970/482-9331 Fax 970/482-9382 5028 a 'S i• it FF .":) r P.. Y i + ,F �.1tr it,.�%I}, •..eo- 1 :. i AV xNX°AW fYUM1 uol. elOxlr.y xrI[+V JULY.JM ab0rvha \ se.x -. - Fiuia•i. 6<auuo Ca...:vvc u5<Inarr•�m+m - �I.a..mavw.,uw•. ir. mmNr.w.„ H reN WA'rC< L..vE u.M.reneemY tlJM4s1�y WWem.ue M'y. 0 > ��B YS.N LrNE W�itnYe.4 •aiiutMW.Md Wm Wf4 �.'�\ ,7m j �" - — ,xvru.w.: a..mrvW.i...kal:r•ma„rw.. \��"�u. >TdJJ�'�\ r.:.....e-uwn.ur...„.•...mlw: rv.r. w�.: :.•Www 9ywsJYma•v..vses.�9..,,,,,,,,w \\ R W.Mla'�� �.eu4mex.°�•°W mwoluv°.u:, -\\ -�\ \ r4.�...rltmiW�v,.s:alm.°IVLMv4vwewi<•ti•ur4mll W�wu `\` .w M 4Ylumu I.W.. �4:;;. I� � \ \ `. w u.s.oe::..wn"".'.u..�ieiwr...,.�<,.•r..... .�. °amu J .. .-._\��\\\ \\\ - w ,<. euer.„abw�wvu..w.q..'aq,...e.vmw ma - ' NOR,oW... \ \ �R \\ \ !� 'a>'J a R ty0 A DRAIA/A6E. TABLE A \ f \ BASF// AREn � TG QsYene Qu YMa Q+, /<I< H rsr°ArV Ca>'SE R.<, 9'L4A. O.LS 4/,r•u. 20<CPA 3.Teu 7.45e.01 D<vazob . Los Set GC 9-WO 040 DETEA/T/OA/ POND VOLUME — C^.rrQVA AREA 4va<eaaAm yd.u.,< 3P44 0 457 r+a /01 rr1 3.I.o 89i fr` rrs 9,250 rA , x z-o n.4es r,• 42.4brn Sb IBi r.>• — "5 Z.8 43171 r.! I LIE AEX r� saszs.•Z•. N SCALE: 60 0 BO in IA'/ CRAFYOC SGVE - FEET ' ^ m v , w o m / , N 0 0 Q �G•[ywmr.�+ V5 000 \ y \ r \ W V 0 30 9 V 65999Y. N [16y F leOf - - v:a9y93k r r q. 5M•.. I \ ,;�\�; �,N"'3 .� q �i �—,-- `< ' <� bvd BplLvy IOy.. SiamRr�miF `5\a\CJVB`'/vJ :/✓ � � � � y IE' • / y �\ � � O ."°'"w City o/ Fort Collins, Colomdo �ko<�.. URLRY PLAM APPROVAL FIFF WIr,SF verx awvansTzx AROVED: . a9sw w u9�.ehrn aa. HECKED BY.. NECKED BY.. cNmarm�� • swrrr.c.4„ ux. �� � 3 � � w.a y aoe xux�n wr r' nieri0 r""°°"' SEDI ECKED BY >.'b4.1oae.• dal9°a„xMr MENT TflAP •\�e a67�- ^•^ •=,>+uunaua9•eanu9 CMOFF COWN; COEORAOO N ECKED BY: \\w3+ uvw a„eNenr SIOxMWREx UNNN swn xwan nb4 SM r r1 BY.• 0-24 OM fT