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HomeMy WebLinkAboutDrainage Reports - 03/28/2004Final Approved Rep�� a JAN 3 0 204 FINAL DRAINAGE, EROSION, AND WATER QUALITY CONTROL REPORT FOR RAM'S CROSSING LOCATED IN THE CITY OF FORT COLLINS CANAL IMPORTATION BASIN PREPARED FOR CHERYL DIPANFILO JANUARY 26, 2004 PREPARED BY STEWART & ASSOCIATES, INC. P.O. BOX 429 103 SOUTH MELDRUM STREET FORT COLLINS, CO 80521 TEL: 970.482.9331 FAX: 970.482.9382 1 ' RAMS XING new 61dq fin rpt.doc I STEWART&ASSOCIATES Consulting Engineers and Surveyors January 26, 2004 Mr. Basil Harridan Stormwater Utilities City of Fort Collins P.O. Box 580 Fort Collins, CO 80522-0580 RE: Ram's Crossing New Building ' Dear Basil, This project consists of one new building, access driveways, parking lots and 4 water quality / ' detention pond areas. The site area that is being disturbed due to the new construction is 0.92 acres. This area is now grass. This project is located in the City's Canal Importation Basin. 11 LJ 1 Anderson Consulting Engineers, Inc. completed an evaluation of the Elizabeth Street flood plain in the location of this project. This study set our finished floor between elevation 5038.5 to 5040.5. We set it at 5040.35. This report is included herein for your reference. This site is West of City Park Avenue and South of West Elizabeth Street. This will be an infill project as all the area around is fully developed. This project will detain and have water quality ponds in four locations on site. We will detain based on the disturbed area for new construction. Historic runoff will be allowed to enter the ponds but will be released at this projects calculated release rates. All designs and calculations within this report are in compliance with the City of Fort Collins Stone Drainage Design Criteria and Construction Standards. All basins in this project use the rational method for runoff calculations. If you have anyNgwwAiQl;g or need more information regarding this report please let me know. ' 4pt4 D e 9% Sincerely, •. •'' Es € • POO Franklin D.�••• . E ��. S. FDB/meh James H. Stewart and Associates, Inc. '103 S. Meldrum Street • P.O. Box 429 • Ft. Collins, CO 80522 R.UIS XIN6 new Bldg fm rpfdae 970/482-9331 • Fax 970/482-9382 1 1 1 1 1 1 1 1 1 1 1 i 1 1 i 1 1 1 1 � 0►n PARK NINE y \\ I—;— SHELpON ugr I V MULBERRY STREET Cc _J Z ORCHARD PLACE ti LAUREL ST o PLUM ST I NORTH DR. W ELIZABETH STREET o C S V W Q4i UNIVERSITY AVE. 2 SITE 7 UWESTWARD DR. G� Q RING IEL DR. BENNETT RD. l W. LAKE STREET 2 0 v PROSPECT ROAD cO Q0 O Dz VI CI NI 7Y MAP �I SCALE 1 "= 1000' ' ' FINAL DRAINAGE, EROSION, AND WATER QUALITY CONTROL REPORT This site is part of The Matador Apartments, Phase III. It is located in the Northwest corner of said Phase III. The Apartments have been renamed to Rams Crossing. The project is in the City of Fort Collins Canal Importation Basin. The area of this project is 0.92 acres, which is defined as the area of existing grass being replaced with a building, concrete walks and asphalt parking areas. ' EXISTING SITE: The site is West of City Park Avenue, East of Bryan Avenue, North of Springfield Drive, and ' South of Elizabeth Street. Our site area is grass and slopes mostly South to North at about 0.75%. There are existing buildings on the West, East, and South of this site and an existing parking lot to the North. An existing storm drain line flow North to South East of our proposed ' building. DEVELOPED SITE: ' This project is an infill project. There is a proposed apartment building which will be slab on grade construction, parking lots on the East and South of the building, an additional parking area ' North of the pool area, and additional parking for the existing building and walkway connection between buildings and parking lots. Also a driveway loop is being created that connects to our building from both the West and East. ' This project is in the Fort Collins Canal Importation Basin and a part of it is in the 100-year flood plain. A study was completed for this site by Anderson Consulting Engineers, Inc. for this ' project. Our finished floor elevation of 5040.35 feet is based on this study. This report is included herein. tA flood plain use permit is required prior to construction, along with a $25 permit application fee. A permit is required for the building as well as any site work done in the flood plain. A ' FEMA Elevation Certificate must be completed and approved for the building structure prior to the release of the Certificate of Occupancy. This site is in compliance with City Code, Chapter 10, Floodplain Regulations. ' This site will be divided into four sub -basins. The area of the sub -basin is of the construction area only. Concentration point for sub -basin 1 is at an area inlet/WQC structure. The sub -basin ' area is 0.48 acres. Required storage including water quality capture volume is 6088.8 cubic feet. The ponds high water line is 5038.2 feet. The pond spillway is the driveway South of the building. ' Concentration point for Sub -basin 2 is the area inlet / WQC structure South of the access driveway. The sub -basin area is 0.074 acres. The total required storage is 886 cubic feet. The ' 100-year pond high water line is at elevation 5037.5 feet. The spillway is into the existing parking lot over the driveway or North over the driveway at elevation 5038.0, which causes the pond storage volume to increase to 2,184 cubic feet due to the higher spillway elevation. 1 ' RANIS RING new Bldg fin rpt.doe I [1 1 1 1 1 [I Concentration point location for Sub -basin No. 3 is West of the existing building and East of the new proposed building. It is an area inlet / WQC structure. The sub -basin area is 0.24 acres. The total required detention is 3044 cubic feet. The pond 100-year high water line is elevation 5036.9 feet. The spillway for Sub -basin 3 is a 20-foot sidewalk at elevation 5036.9. Overflow is West to the existing parking lot. Concentration point for Sub -basin No. 4 is Northeast of the new parking lot North of the pool area. It is an area inlet/WQC structure. The sub -basin area is 0.126 acres. The total required storage is 1532.5 cubic feet at elevation 5036.5 feet. The spillway is Northwest over the sidewalk at elevation 5036.5 to the parking area. All sub -basins require a restriction plate for orifice opening sizes and also water quality restriction plates for the 40-hour extended storage requirements. All drainage calculations are included herein. EROSION CONTROL: The City's required erosion control cost estimate for this project is $6,000. Erosion control will be to install a silt fence around the construction site. Also a straw bale dike will be constructed around all open-ended pipes and or inlets for each sub -basin. The building foundation will be installed and graded first. All parking areas will be required to be graveled as soon as they have the sub -grade prepared in all parking lots. 1 RAMS XING new bldg rm tpLA,e a, 1 1 1 1 i 1 1 1 1 1 RAINFALL PERFORMANCE STANDARD EVALUATION --------------------------------,-----------r------------------------- PROJECT: STANDARD FORM A COMPLETED BY: �J,yw / DATE: Z� ---------------------------------------------------------------------I DEVELOPEDIEROOI SUBBASIN I ZO 571? F"51" ::, BILITY NE ------ era Asb I (ac) I -------I------- �.D-2� I (ft) I ( % ) I------- C? I(feet) I------- I (wo b) I------- I (S) I I -------I I I i D, 9Z i 2g�,�: i /' �7 I I 74 I I I I I I I I I I I I I I I I I I I I I I --------------------------------------------------------------------I I/SF-A:19,99 11 /5 [_I [1 1 1 1] EFFECTIVENESS CALCULATIONS PROJECT: DAMS C cOS0/.�O✓ — 1J CW If-,1L r!,v STANDARD FORM B COMPLETED BY: - •,E? DATE: 7_ Erosion Control C-Factor P-Factor Method Value Value Comment �A 01L 1.00 ,O/) 5,4 F;-,•/` ! O • +jC7 risps+4tT �r C- OtiGT.r- � 0,01 /• 00 JED%M�%Ji 0ASrn1 I.Oa L7r1!o ! OvtiJC>A oti 0.61 l e� 10,5 MAJOR PS SUB AREA BASIN (1) BASIN (Ac) CALCULATIONS CA",! %B•1 S•�� O•��Ac. I ,� c. - SOU J.J D •a T!O/.J �. 1 1 AG. L5T-A8L/S c GRAB, p, l L.c. w C- U0.01A 0-m)4 (1�0pxo•41)4(0,01X0.1))+�0.08x0.13)� O. 7? wry C = O•ss 040 EFF = I- (O.�sX O.40) x IdO _ 7870 k [j [1 1 11 EFFECTIVENESS CALCULATIONS PROJECT: JP 4nns r KorS ,vt- — h,)E-co ;'_UIL.D+;I% STANDARD FORM B COMPLETED BY: k., DATE: Erosion Control C-Factor P-Factor Method Value Value Comment 13, P_F SOIL /.00 /.00 S IL I A ra_i�,� 1.00 0.80 /ASP/-ia,LT C-0"CCEra 0.01 /.00 '0Ac-t,v /.00 Q,SO Fou a r>.4 -t0 J Li,O! 1,00 �S ;rA, �Lt� y E+� Genss O.OPj 1, DO MAJOR PS SUB AREA BASIN (1) BASIN (Ac) CALCULATIONS Al. AL LMr 7�.1 S•F. Z 6,Z C7 _.00A,` Ac 13 Ast,u B AFZC= O+� 09 qc. FSTAI3LISHE&g4SS 0.01- pC- CU-rD C = CO• ��lX O0S) t-(/,DOX0,0'j)-f- �O.OSXO.06) O,Zp wTDC O.O� 005-+ 0,0,7 ul-ra C. D, 48 W I 1 I I EFFECTIVENESS CALCULATIONS PROJECT: /C MS nSSJ,1� - XJE a v;� -•LNG STANDARD FORM B COMPLETED BY: DATE: Tl%ham Erosion Control C-Factor P-Factor Method Value Value Comment A P_.E SOIL 1.60 I.00 S J LT FENCE SA er_}E,ti /• DD 0,J'A0 /. 60 0i50 l- 0 U,V U /1 7-1 O /._I BASE AA ATE 0.01 1100 e;<, E-ST,c� B'�S �;VJia AsS 0.04, /,00 o, Os IOD MAJOR PS SUB AREA BASIN (�QQ) BASIN (Ac) CALCULATIONS LM,?Ac. _GO AdCP_ rou 0I Dn- �,c, ESTAf3C /Sl'GL? O, Lo A•G• BASF J�i�T�,e; .!_ J •. �7 . t'.:. J.JT 1 C;�o 01:; J,Os�� (.lXo,l6)±. j,0/ XD. J �d_Q3�0,_g�)+ •N X0.�7� v,sa U1TU, C = O• D005 } ...D , z$ 0• C 044- 0_00b4-+ D•,004z wrD.c = os4 I-�0.54XO•q-0) %00� f bK ATE, f:? �1 n�Q ro NAYS � FF; CrCX,-rr 78,a o/ 'o j I I 1 1 1 1 1 1 EFFECTIVENESS CALCULATIONS PROJECT: ,PA iA C t~ Oss:;vC, STANDARD FORM B COMPLETED BY: p_ , /� , DATE: Erosion Control C-Factor P-Factor Method Value Value Comment LUACF 501L i100 1,00 311--r FaA)ce G,4epr=;c I.OD O.oO CDNCb_'c'T,_ O•D1 1,00 tw tJ rD AT10 u 0.01 /;00 r5rA., ea5S O,019l dd MAJOR PS SUB AREA BASIN BASIN (Ac) CALCULATIONS CAA,AL. IMP. 78-I SSa4 0 4(oAc, _COQC.rz D. EC7-A 8LISH E�orASS 1 Z Ac. UJTD. C._ �Q._Q I_X D,1Z� f- �__l•D x (�•zz _�-_ O0.8X O,IZ� VJ C. W T D C = O,SD ITV T D 50 ;<. 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FOR JA` r ONLY COMPLETED BY: — t.— DATE: kiIndicate by use of a bar line or symbols when erosion control measures will be installed. ajor modifications to an approved schedule may require submitting a new schedule for pproval by the City Engineer. ' YEAR MONTH I- --------------- �VERLOT GRADING I I 14IND EROSION CONTRUL I 'Soil Roughing Perimeter Barrier Additional Barriers Vegetative Methods 'Soil Sealant Other LNFALL 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/Blankets Other I------------------------------ �UCTURES: INSTALLED BY GETATION/I.IULCHING CONTRACTOR IE SUBMITTED /SF-C:1989 I F I K I K Inil _s -I_-E I N I I ---- r---- ----- - MAINTAINED BY APPROVED BY CITY OF FORT COLLINS ON I 1 I I 1 I I I I I 1 I I 11 I I I STEWART&6SOCIATES 103 PH. S. 9 LDiRUM, FORT gOLLINS, CO 80521 Consulting/Engineers and Surveyors / FAX By: / o'%✓/> Date: 2 Client: gZ�//-'orh /r///Qc��?/ri Sheet No. of Project: Gf'UT�/itJ_fi Subject:.QO.�%ON 2. /ZOO LF�/L���NCE Torte � °��fOaD 1 STEWART&ASSOCIATES 10 SS. ME D1Rf X 48 ROT $OLLINS, CO 80521 CO �sultii -13 En3ineers and Surveyors By: —✓�%/1 Date: �,= Client: G'i'y /// /%j > Sheet No. = of Project: c �'J //�� /'' J �4G tJ ^� ✓ Q! H Subject: 1 STEWART$,LSSOCIATES 103 S. MELDRUM, FORT COLLINS, CO 80521 Ph. 482-9331 FAX 482-9382 1 Consulting Engineers and Surveyors By: Date:: Z d? Client: 1 Project: Subject: S 0 Sheet No. of a4�e/ I 1 1 1_1 11 c c c C f f cr- 0 F- o v /AT c C) 0 0 W Z = 0 0 °r a U— Z II Z U) d 0 Q m E— m Z :D W v) F— LU ♦� a W C 3 � II 0 00 Wcr- 0 ---------------------- W IT W W W M W to N N M r W W IT O Moo 00 O 00 IN J W W— W—M00p0rm0r- WW0- WIN OrM IT0moomo0w In NN1�;, Z.R.,C�D g1C`prdC4) lt�t r CV) CV) e' 't I Mt � tt L0n WgNrNINNCM Lf) In 't U 1 0000000000000000000000 O CDN00 MN0 O(DN00�0(DN 00rInO0NfD C C� co 1�-IN0):WNcocoQ� 00 N"-N000(p r r r `L I r � U 00cf(C)0W Cl) WLoNNLor(pW ONCO.MOwN LL C(M, M((��JJpr(C��W0r0001nm ntnL(jNW q* -M �l �O(pr(pN](pN� N0In (p �`�I rNIV ('7MM��d �t It ��NtU(pCDCO U cc ------------ �p aD aD ao ao co aD 00 v�vct�14: co 00 co 0o 0o co co V 00 Id: co co co 00 00 00 Q o000000000000000000000 d;>I;crItv It U a) � U U ca ll7NN000N00��tNO000(Op�tNO0)000W O I� lA (p Cn In O t\ lq-rO O N W O"t-t . Z Ac, W C F- Z 0000000000000oo000'0000 uiC;L6 r r(�NnMIt )riouifouioL0000000'o wt O Lo Co P 00 O 0 r�:N. uiouio CM to(p LU r r r r r r �0. 00 r .0 p: I 1 1 1 1 1 11 1 i 1 1 1 1 1 STEWART&ASSOCIATES Consultin3 En3ineers and Surveyors By: Date: / v Client: _ Project:-o rr7i G/DSFi/9� /f/�c.J - Subject: 103 S. MELDRUM, FORT COLLINS, CO 80521 PH. 482-9331 FAX 482-9382 Sheet No. of r-,shay& -w d 3 112 t011Wo� &q;:�l V-� ( '* S/10. 1w !7/� C V 7 Tom I r- . I I I I I I 1 I C I 1 1 DETENTION POND 1 HIGH WATER LINE VOL. = 1/3 (AREA ABOVE) (DIFFERENCE IN COUNTOUR ELEV.) 2. FOR THE REMAIMDER OF THE VOLUMES BETWEEN CONTOURS (SECTION 9.2) VOL. = DEPTH/3 (A +(AB) ^ .5 + B) FOR: Uniform Sides sec.(9.2) 3. HWL=(VOL.REQ.—VOL.LOW CUML)*3/(AREA LOW+AREA HIGH+(low area*high area) ^ .5) 38.19 H1NL POND ORIFICE SIZING ORIGINAL DESIGN DATA 0.12 = Allowable Des. Release Rate cfs NOTE: 1. VERT. PLATES WILL BE PLACED 33.00 = Flowline Orifice Elevation ftAT PIPE FLOWLINE 0.65 = Orifice Coefficient Cd 5.19 = Avaliable Drivin Head ft ' DETENTION POND 1 WQ GRATE EL EVATION (MIN) I I I I I I I 11 1 I I I I I VOL. = 1/3 (AREA ABOVE) (DIFFERENCE IN COUNTOUR ELEV.) 2. FOR THE REMAIMDER OF THE VOLUMES BETWEEN CONTOURS (SECTION 9.2) VOL. = DEPTH/3 (A +(AB) ^ .5 + B) FOR: Uniform Sides sec.(9.2) 3. HWL=(VOL.REQ.—VOL.LOW CUML)*3/(AREA LOW+AREA HIGH+(low area*high area) ^ .5) ORIFICE SIZING 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 f EMERGENCY SPILLWAY DESIGN Weir Equation Q = C L (H) ^ 3/2 Q (cfs), C (weir coefficient), L (crest length, feet), H (energy head, feet) 24 = Weir Length L in feet 3.1 = Weir Coefficient Weir Shape Broadcrested Design Flow 4.78 (cfs) �� p Depth of flow (ft) Flow Over Weir (cfs) 0.05 0.83 0.10 2.35 0.11 2.71 0.12 3.09 0.13 3.49 0.14 3.90 0.15 4.32 0.16 4.76 0.18 5.68 0.50 26.30 3 7>rr✓�- wa� I I I I 1 i 1 [1 1 1 1 1 1 STEWART&ASSOCIATES Consulting Engineers and Surveyors By: �/,2 Date: c.7a.." Client: Project: Subject: 1 103 S. MELDRUM, FORT COLLINS, CO 80521 PH. 482-9331 FAX 482-9382 Sheet No. /%' of .. h//s /,W/C A2el;zor �Tc , . z .� /. Tx K D, D7v = D, OZS /f�5 I I I I I 11 I I n I 1 1 1 I 1 1 1 STEWART&ASSOCIATES Co nsultin g Engineers and Surveyors By:—✓/fGr/7 Date: Client: Project: '2� �D''S/l7ca Subject: Li x-/;0/ �'//'' /jam 103 S. MELDRUM, FORT COLLINS, CO 80521 PH. 482-9331 FAX 482-9382 Sheet No. / / of 3 - Z 2I-4ir7 ySC' -min I /Z- [1 I 1 u 11 1 I Cc 0 '' w ' i ECMM� C) Q W Z i = 0 m N � Z COZ O Q c _ m Z Z) W (n H c I W c m ¢ D II U, c a W c �fCOf�MMTLnNCf)T� (nr LnrOOOLnI�ON Vw Cir�rr:LCii:T�MNI�r6N T NM Nr W cor WLn COONet LncDCDtD f�O cDNKNr CV) q:066MIWOU It CM co N�'NmNU) .ln Cn A U � 7 C � I � LnOlnOlnOlnOlnOln00000001n0 i� L6 (� O I� Ln N O I� Ln CV O Ln0 r-N C' m -LnCDCDNCo0) lCj &MLOWw Ln O Ln 0.C1 Ln f� 0 O � _I F- � U O 0)COOJMC)r0NchrMMrEn79O:OON LnN )LL �(N r�NN�'d'T^Or No00co 0N�A MLn In cD LL B N�7MIn0MCDCArMCDO�nf� ,it Ln CO CD CD CD n � � 0 00 0 CO A CA 80) )p ) Z 3 � � U > O O AA O O O O o 0 0 0 0 0 0 AA 0 0 0 o A O: A O O O O Q o 0 o 0 0 0 0 0 o 0 0 0 0 0 0 0 0 o 0 0 0 0 U � * U U ca LO (mNLoCDcntoof� N C4 0 w cm co ItcDMMCpO W N000co�YNOCAOOCDgt 0000LnLn Ln 0 6r%:CDLn4et cr6MMchNNCVNNT,r;TTrT Z� .c F- wz Ooo00o0000000000.r00000966MOLrioln00oo�ppo6L6q6NMM��LncoN W C LCDO r T 00 I STEWART&ASSOCIATES 10 82 9 3DRF , FORT '/ddinCOLLINS, CO 80521 ' Consulting Engineers and Surveyors 482-9382 By: Date: Client: Bi /%11 10 Sheet No. of ' Project: �/ji7 : /OAS1.0 AV Subject: ewlGd ✓ayeVO/�n-�c s /ZD� � 'O�Vd Vl D, 9�5'' t . D 2o�/--XJ e ,67 �o 771 /Z /2 • o , /20 d yy �-�", . _ /, Dd2 � y�.:5G0 = /07 C ' row a DETENTION POND No 2 HIGH WATER LINE VUL. = 1/3 (AREA ABOVE) (DIFFERENCE IN COUNTOUR ELEV.) 2. FOR THE REMAIMDER OF THE VOLUMES BETWEEN CONTOURS (SECTION 9.2) VOL. = DEPTH/3 (A +(AB)^.5 + B) FOR: Uniform Sides sec.(9.2) 3. HWL=(VOL.REQ.—VOL.LOW CUML)*3/(AREA LOW+AREA HIGH+(low area*high area) 3TA2 = HWL POND ORIFICE SIZING nRIf;INAI nFclr_ni nATA 0.03 = Allowable Des. Release Rate cfs 36.90 = Flowline Orifice Elevation ft 0.65 = Orifice Coefficient Cd 0.52 = Avaliable Drivin Head(ft) IHORZ. CIRCULAR PLATE SB No 2 EMERGENCY SPILLWAY DESIGN I _Weir Equation Q = C L (H) ^ 3/2 Q (cfs), C (weir coefficient), L (crest length, feet), H (energy head, feet) [1 I I _ 48 = Weir Length L in feet 3.1 = Weir Coefficient Weir Shape Broadcrested Design Flow 2.39 (cfs) '/ Depth of flow (ft) Flow Over Weir (cfs) 0.03 0.77 0.04 1.19 0.05 1.66 0.06 2.19 0.07 2.76 0.10 4.71 0.20 13.31 0.30 24.45 0.40 37.64 0.50 52.61 a�r�ve u.): y S I 1 I II 1 1 1 I 1 1 Ci 1 1 1 1 STEWART&ASSOCIATES Consulting Engineers and Surveyors By: J? G' ft Date: 4 G� O Client: Project:. Subject: 103 S. MELDRUM, FORT COLLINS, CO 80521 PH. 482-9331 FAX 482-9382 Sheet No. 16 of LJ STEWART$,LSSOCIAT Consulting Engineers and Surveyors By: _.rn�C/C Date: ' Project: Subject: [1 I 1 1 I I 1 I I 1 1 103 S. MELDRUM, FORT COLLINS, CO 80521 PH. 482-9331 FAX 482-9382 Client: 4�2n " Sheet No. ZZ of 1 1 1 1 1 i 1 1 1 1 1 i 1 1 1 1 cl: 00 W Z O CL M OZ Z Q om F-- m Z D w U) 0 0 D 0 cr r * * d I�MCOCOtOmIN 000000MMcmpOtO�tgq*0'tw �N�( 'wR j(O,�O! to N [j4�] OT � N N � N M ONO: * N^ f'� ON V V W O � O V/ po T Ln �A�pN(p �g TTr-T+ TN N NNNN,NNNN M O 3 N � U II O�OppOOOpOpp��N OppOOOOOOOO�OpO�OOOOO OO$�('JLn�Q�O(NDOOO�CTON CN7t")(')�,���� T T r T T T CM \V � U U- MOCNRC^aN�COO ,O+ CO: ONCN"C9r NNTCOMU NU cat�rnpOOrC& Nl tCV) MCN^NO J 1 CV II N NNNNNNNNNNNNNNNNN:CV'NNNN oQ 600666666000006600C5600 U � U � LID IN CONCD�cDMMM�ppppp o8LOLOLO CANtoOCALnONItN000OOO CID C0'4tT0 CAI�<DLn��ttMML`�c7NNCV NC T V4, r-r U U) 0O W C cZ r— II OOOpOOOOOOOpOLO�pOOOOooOOOOpOLO�O j L!)O VORR88 U4,OLnOORO�8T6::RCP82(3 L, C T T rN, tr r T r STEWART&ASSOCIATES 103 S. MELDRUM, FORT COLLINS, CO 80521 PH. 482-9331 FAX 482-9382 ' Consulting Engineers and Surveyors By: 'Iazly 1 Date: 4 Z 4)3� Client: i O Sheet No. L7— of ' Project: Subject: �Xr�iv.�e'O_ Ilo/ �?cV 1 1 , •: ro �S$ /f% `! S' �Z ��� . )tom, - .a. .5 i� 4�'000e dr v".aD7 Da9.7y3 �D ..%zjai c� �S ' 1 f 1 , /Ivry I.. 1 , 1 , 1 � { 1 r ell i i { t 1 I I I 11 I I I I I 1 1 DETENTION POND 3 HIGH WATER LINE VOL. = 1/3 (AREA ABOVE) (DIFFERENCE IN COUNTOUR ELEV.) 2. FOR THE REMAIMDER OF THE VOLUMES BETWEEN CONTOURS (SECTION 9.2) VOL. = DEPTH/3 (A +(AB) ^ .5 + B) FOR: Uniform Sides sec.(9.2) 3. HWL=(VOL.REO.—VOL.LOW CUML)*3/(AREA LOW+AREA HIGH+(low area*high area) ^ .5) ORIFICE SIZING ORIGINAL DESIGN DATA 0.06 = Allowable Des. Release Rate cfs 33.32 = Flowline Orifice Elevation ft 0.65 = Orifice Coefficient Cd 3.58 = Available Driving Head ft VERT. SQUARE PLATE NOTE: 1, VERT. PLATES WILL BE PLACED AT PIPE FLOWLINE 1 1 1 1 1 1 i 1 i 1 i 1 1 1 i 1 1 EMERGENCY SPILLWAY DESIGN Weir Equation Q = C L (H) ^ 3/2 Q (cfs), C (weir coefficient), L (crest length, feet), H (energy head, feet) 20 = Weir Length L in feet 3.1 = Weir Coefficient Weir Shape Broadcrested Design Flow 2.39 (cfs) Depth of flow (ft) Flow Over Weir (cfs) 0.05 0.69 0.10 1.96 0.11 2.26 0.12 2.58 0.15 3.60 0.20 5.55 0.25 7.75 0.30 10.19 0.40 15.68 0.50 21.92 1 1 1 1 i 1 i 1 1 1 1 1 1 1 STEWART&kSSOCIATES Consulting Engineers and Surveyors By: o%L� Date: 03 Clie Project: Subject: 103 S. MELDRUM, FORT COLLINS, CO 80521 PH. 482-9331 FAX 482-9382 Sheet No. Zu of STEWART&ASSOCIATES 103 S. MELDRUM, FORT COLLINS, CO 80521 Consulting Engineers and Surveyors PH. 482-9331 FAX 482-9382 1 By: Date: Client: Sheet Noj—J of Project: lw /w Subject: / -57 71 : i 2�Co/vcN�ro 00D- 1 �. , r J • , } i y I E j00 , 1 1 1 1 1 1 C) r 0 W Z =O Oz Z Q O m F— m z D F I 0 Lij * NCOI- 0 M0001nMT1�ON�.f�C)COti CO N Lo* Lo,w n� �oD�0 C� N��� O N � U II NN, M � A p C, E T-00 f�NTCOOT00M0N000"0:OMLOCO CC Q� �InCAT���jjQ�Ipp���In�(DNO "LPL M^OO�TNNNO�`�d OtMA(pt0 V 00 w CC U II M MMMMMMMMMMMMMMMMMmMMm oQ o00ao00000In000000(0;0000 U L) _ U 0n Z 7Z r- 7 CW C NLOCOOL01��NI lwl� ol o� �j 0coco V000000st�O r- C(6ui44-It MMMMNNNNNrt�',TTrr 00 00MO�ri � -LO CD1%- T♦V MoC5 LO 1tH %LW G LJ I STEWART$,06SOCIATES Consulting Engineers and Surveyors 103 S. MELDRUM, FORT COLLINS, CO 80521 PH. 482-9331 FAX 482-9382 By: a?G Date: Client: ��C✓�, / /7,7h 1 s !O Sheet Noc2% of .•-�'7 it 1 Project: Subject: I I , Ope- I' 1 1 1 1 i i 1 1 1 1 1 1 ,?Ieo DETENTION POND 4 HIGH WATER LINE VOL. = 1/3 (AREA ABOVE) (DIFFERENCE IN COUNTOUR ELEV.) 2. FOR THE REMAIMDER OF THE VOLUMES BETWEEN CONTOURS (SECTION 9.2) VOL. = DEPTH/3 (A +(AB) ^ .5 + B) FOR: Uniform Sides sec.(9.2) 3. HWL=(VOL.REQ.—VOL.LOW CUML)*3/(AREA LOW+AREA HIGH+(low area*high area) ^ .5) 36.4;7 = HV1lL POND ORIFICE SIZING 0RIr,INA1 nF4Z1tZK1 MATA 0.04 = Allowable Des. Release Rate cfs 34.16 = Flowline Orifice Elevation ft 0.65 = Orifice Coefficient Cd 2.31 = Avaliable Driving Head ft NOTE: 1. VERT. PLATES WILL BE PLACED AT PIPE FLOWLINE I 1 1 I I I I I I I 4 SB No 4 EMERGENCY SPILLWAY DESIGI` Weir Equation Q = C L (H) ^ 3/2 Q (cfs), C (weir coefficient), L (crest length, feet), H (energy head, feet) 20 = Weir Length L in feet 3.1 = Weir Coefficient Weir Shape Broadcrested Design Flow 1.29 (cfs) Depth of flow (ft) Flow Over Weir (cfs) 0.05 0.69 0.06 0.91 0.07 1.15 0.08 1.40 0.09 1.67 0.10 1.96 0.20 5.55 0.30 10.19 0.40 15.68 0.50 21.92 ZO, /evG• -5 /Do r ow,dm p,0� I No Text DRAINAGE CRITERIA MANUAL 50 30 1,- 20 z W U tr a 10 z W IL O 5 W cc 3 O v 2 W t— a t 1 RUNOFF �■�■■n■■ ■m■■�� r■ANIMM FA FAME MEN % ■ , I■■■■1111111 / Mz YEA III ■��'�I ����■■■■� ��AMWANPANF/IMWAVAM�MMENNIN�IS -AMWAN ErAl lirMAM�MMyOSI�� 2 .3 .5 1 2 3 5 10 20 VELOCITY IN FEET PER SECOND FIGURE 3-2. ESTIMATE OF AVERAGE FLOW VELOCITY FOR 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 1 I 11 1 1 I City of Fort Collins Rainfall Intensity -Duration -Frequency Table for using the Rational Method (5 minutes - 30 minutes) Figure 3-1a Duration (minutes) 2-year Intensity in/hr 10-year Intensity in/hr 100-year Intensity in/hr 5.00 2.85 4.87 9.95 6.00 2.67 4.56 9.31 7.00 2.52 4.31 8.80 8.00 2.40 4.10 8.38 9.00 2.30 3.93 8.03 10.00 2.21 3.78 7.72 11.00 2.13 3.63 7.42 12.00 2.05 3.50 7.16 13.00 1.98 3.39 6.92 14.00 1.92 3.29 6.71 15.00 1.87 3.19 6.52 16.00 1.81 3.08 6.30 17.00 1.75 2.99 6.10 18.00 1.70 2.90 5.92 19.00 1.65 2.82 5.75 20.00 1.61 2.74 5.60 21.00 1.56 2.67 5.46 22.00 1.53 2.61 5.32 23.00 1.49 2.55 5.20 24.00 1.46 2.49 5.09 25.00 1.43 2.44 4.98 26.00 1.40 2.39 4.87 27.00 1.37 2.34 4.78 28.00 1.34 2.29 4.69 29.00 1.32 2.25 4.60 30.00 1.30 2.21 1 4.52 't o [1 1 11 1 1 1 1 1 1 1 1 1 1 L 1 1 1 City of Fort Collins Rainfall Intensity -Duration -Frequency Table for using the Rational Method (31 minutes - 60 minutes) Figure 3-1 b Duration (minutes) 2-year Intensity in/hr 10-year Intensity in/hr 100-year Intensity in/hr 31.00 1.27 2.16 4.42 32.00 1.24 2.12 4.33 33.00 1.22 2.08 4.24 34.00 1.19 2.04 4.16 35.00 1.17 2.00 4.08 36.00 1.15 1.96 4.01 37.00 1.13 1.93 3.93 38.00 1.11 1.89 3.87 39.00 1.09 1.86 3.80 40.00 1.07 1.83 3.74 41.00 1.05 1.80 3.68 42.00 1.04 1.77 3.62 43.00 1.02 1.74 3.56 44.00 1.01 1.72 3.51 45.00 0.99 1.69 3.46 46.00 0.98 1.67 3.41 47.00 0.96 1.64 3.36 48.00 0.95 1.62 3.31 49.00 0.94 1.60 3.27 50.00 0.92 1.58 3.23 51.00 0.91 1.56 3.18 52.00 0.90 1.54 3.14 53.00 0.89 1.52 3.10 54.00 0.88 1.50 3.07 55.00 0.87 1.48 3.03 56.00 0.86 1.47 2.99 57.00 0.85 1.45 2.96 58.00 0.84 1.43 2.92 59.00 0.83 1.42 2.89 60.00 0.82 1.40 2.86 1 I DRAINAGE CRITERIA MANUAL (V. 3) 9-1-1992 UDFCD STORMWATER QUALITY MANAGEMENT 3Z 0.5 Extent: 10-Hot ed De r Draij entior i time Bast (Dry) 0.4 0.3--[ 0.2 D 1 tents -Hour n Pon Drain Is (W Time t) �.1 0 to [u ' 30 40 so 60 70 80 90 100 Percent Impervious Area in Tributary Watershed Source:Urbanos. Guo;Tucker (1989)• Note: Watershed inches of runoff shall apply to the entire watershed tributary to the BMP Facility. FIGURE 5-1. WATER QUALITY CAPTURE VOLUME (WQCV) i 1 1 1 1 1 1 i 1 1 1 1 1 1 1 1 1 1 DRAINAGE CRITERIA MANUAL (V. 3) m 0.6( me 0.0: STRUCTURAL EMPs on - O P VA 0MEN SOLUTION: Required Area per o Vonsvp AIAJOAA IANA 61 MORENO! PAA FAA FAA Ell 11 loll loll 11 0.0, 0 0.40 0.60 1.0 2.0 4.0 6.0 Required Area per Row (in.2 ) Source: Douglas County Storm Drainage and Technical Criteria, 1966. FIGURE 5-3. WATER QUALITY OUTLET SIZING: DRY EXTENDED DETENTION BASIN WITH A 40-HOUR DRAIN TIME OF THE CAPTURE VOLUME 9-1-1992 UDFCD DRAINAGE CRITERIA MANUAL (V. 3) STRUCTURALBMPs (r Threaded Cap Water Quality Capture Volume Level (including 20% additional volume for sediment storage) Gravel (1-1/2'to 3' Rock) Around Perforated Riser Filter Fabric Water Quality Riser Pipe (See Detail) Notes: 1. The outlet pipe shall be sized to control overflow into the concrete riser. 2. Alternate designs include a Hydrobrake outlet (or orifice designs) as long as the hydraulic Performance matches this configuration. Notes: 1. Minimum number of holes - 8 2. Minimum hole diameter m 1/8' dia. 9-1-1992 UOFCD i Rows 1:� O O O\ O O Access Pit (Min. 3 ft) OUTLET WORKS NOT TO SCALE 1-12" diameter Air Vent in Threaded C Water Quality Outlet Holes Ductile Iron or Steel Pipe WATER QUALITY RISER PIPE NOT TO SCALE Removable & Lockable Overflow Grate for Larger Storms Pipe —► Size Base to Prevent Hydrostatic Uplift Maximum Number of Perforated Columns Riser Hole Diameter, in. Diameter 1/4' 1/2' 1 3/4' 1' (in.) 4 8 8 - 6 12 12 9 - 8 16 16 12 8 10 20 20 14 10 12 24 24 18 12 Hole Diameter Area of Hole (in.) (in.2 ) 1/8 0.013 1 /4. 0.049 318 0.110 1/2 0.196' 5/8 0.307 3/4 0.442 7/8 0.601 1 1 0.785 FIGURE 5-2. WATER QUALITY OUTLET FOR A DRY EXTENDED DETENTION BASIN 4+B •G3 I 1 ANDERSON CONSULTING ENGINEERS, INC. ELIZABETH STREET FLOOD PLAIN EVALUATION 1 THE RAM'S CROSSING APARTMENTS ADDITION 1 1 I I 1 L �I I I I ' ` ) ANdERSON CONSUITINCt ENCtiNEERS, INC. ' Civil • Water Resources • Environmental ' June 10, 2002 Chuck -and Cheryl DiPanfilo ' Walnut and Main 4787 Valhalla Drive Boulder, CO. 80301 RE 1 1 LJ 1 Elizabeth Street Floodplain Evaluation the Ram's Crossing Apartments Addition (ACE Project No. COWA1N101) Dear lvlr. and Ms. DlPanfllo: Anderson Consulting Engineers, Inc. is pleased to inform you that we have completed our evaluation ofthe Elizabeth Street floodplain in the vicinity of the proposed project site at the Ram's Crossing Apartments and respectfully submit this letter report with supporting documentation. In conducting this evaluation, we reviewed the hydraulic (FIEC-RAS) model of the Elizabeth Street/Constitution Avenue Flow Path prepared as part of the Canal Importation Basin Master Drainage Plan [Anderson Consulting Engineers, May 2001 ] and visited the project site in order to observe existing site conditions. It is Our understanding that the proposed project includes the construction of parking lot and one or more apartment buildings in a currently undeveloped portion of the Ram's Crossing Apartment complex. The current study area/project site is shown on the annotated Plate 7 (attached); this is a portion of the Elizabeth Street floodplain map taken from the master drainage plan. Approximately two-thirds of the site is located in the 100-year floodplain associated with the Elizabeth Street Flow Path. In vcneral, there are two issues concerning the tloodplain with regard to the proposed project: (1) elevating any proposed buildings that would be located in the regulatory floodplain above the 100- vear flood level; and (_') placing fill in the re,trlatory floodplain that would cause an adverse impact to adjacent properties due to obstruction of'effective conveyance along the identified flow path. With regard to the first issue, any buildings constructed in the defined floodplain would be required by the City of- Fort Collins to elevate their first floor levels a minimum of l8 inches above the associated 100-year water surface elevation. For the current project site, this would mean that a buildill"'s finished floor elevation would have to meet or exceed 5038.5 to 5040.5 feet, NGVD depending on the specific location within the site. Concerning the second issue of not adversely impacting adjacent properties, the City currently requires that any improvements in the 100-year floodplain in this area result in a "no -rise" condition P`( WI lAMI'llPQOCIC011'11101-L(RRP7'll'TO how 11). y)Oj 772 Whalers Way, Suite 200- Fort Collins, CO. 80525 Phone: (970) 226-0120 • Fax: (970) 226-0121 • «ww.acewateccorn i 1 1 1 1 Mr. and GIs. DiPanfilo Page Two June 10, 2002 with respect to 100-year flood levels. In other words, any fill within the floodplain cannot create a rise in i 00-year water surface elevations. The project site includes two different types of floodplain designations: (1) the shallow flooding area in the western frinue of the property; and (2) the detailed flooding area over the remaining portion of the site. The shallow flooding area was designated to provide a logical transition/pathway for flood flows that would spill from the Larimer County Canal No. 2, to the detailed flood zone along Elizabeth Street. The canal spills need to have a path from the canal, to the north and east, to the street. There is an existing wood privacy fence along the north and west perimeters of the project site, this fence is shown in Photograph No. 1. Although the fence has a "shadow box" configuration, rather than being solid, it effectively obstructs the path of the flow arising from the canal spills. Consequently, the proposed project site provides little if any effective conveyance for the canal spills; it appears that most of these flows would be directed north along the entrance drive and along the east side of the adjacent apartment building to the west. Therefore, it is our opinion that placement of till within the shallow flooding zone would have no effect on flood levels associated with flows arising from the 100-year spill from the canal. However, in order to avoid the appearance of creating an obstruction, it is recommended that any elevating of ground levels in this area be kept to a minimum. The detai led flood zone includes all hydraulically connected hooded areas adjacent to the main flow path along Elizabeth Street. The parking lot adjacent to the north side of the project site is shown in Photograph No. ?. A review of the floodplain mapping for this area determined that while no HEC-RAS cross sections intersect the site, two cross sections closely bound the site on the east and west. These cross sections (Nos. IS85 and 2135) are shown on Plate 7. Photograph Nos. 3 and =4 provide a view of site conditions near these two cross sections. A detailed review of the hydraulic model for the Elizabeth Street Flow Path, in combination with observance ofexisting site conditions, indicate that the project site is ineffective for the convevance o f flood flows along Elizabeth Street. Graphical plots ofthe two bounding I-IEC-RAS cross sections are attached. Cross Section 1885 is encroached approximately 70 feet inside of the northern boundary of the site (the north fence line) due to the existing building east of the site. In addition, the 100-year flow at Cross Section 2135 does not spread onto the site south of the existing fence. Consequently, the hydraulic model does not consider the project site to be effective for flow conveyance. In addition, the presence of the wood privacy fence, while allowing the site to flooded due to backwater conditions, precludes the area south of the fence from being effective for conveyance. Therefore, it is our opinion that any fill, or elevating of the existing ground, within the detailed flood zone portion of the project site would not create a rise in 100-year flood levels along the Elizabeth Street Flow Path. /':'C Uq: 1AM/111 I WOC' C()1P: IMP I -L rRR11L 11po ./ond 10.'00' Mr. and Ms. DiPanfilo June 10, 2002 Page Three In addition to the attachments identified above, enclosed is a "no -rise" certification required by the City of Fort Collins. It has been our pleasure assisting you with the floodplain evaluation for your site. Please do not hesitate to call if you have any questions or comments concerning any of the information provided in this letter report and documentation. Sincerely, SULTING ENGINEERS, INC. G. r�J.,l(oth, P.E. V' e re ident GJK/tlt Attachments cc: Ms. Marsha Hilmes-Robinson, City of Fort Collins Stormwater Department Mr. Carr Bieker, The Architects Studio Mr. Dick Rutherford, Stewart & Associates P:1CO141d10!'I WITOCCOII':0101-L TRRPT. 11 Pp June 10, 2002 — _ — Y" 5z`�T+32 _ -_: _� �•-� . � 'c"t:�� _ � P L SfT ,� _ r ,� _ •r - .:r.4,?{ i.-3 j •,. erg. ..., ,. ._ - '•'. -...., .:;.. _. ,. ,-�:� �' �. - - - — '�.; _ �'.` - ems,+. >li. ;:�"- - _ jj An i _ _r 17 M \ - { ' �• .,� _ �.,0 N 0 •f .;. .._ ,... '.m b,.r 1. ., w s�.-' II -�,h � fir' -fib � r �� , . ••... n _� 4.. :.F '.." ..O J,,. :il, -.: t,. Y ��` M Pry.: _ ,.,F -.. I n�a ��> ,?� '. � i ,. {_.�•. ..1 � •...; � ._ '..::,r � O) •.".•". is .M �,,: `A ,.... "^. _..:` ;�; _ " 1 a8 w `� ,.., ' - � u ' :! 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I J77r r-c' :�. x,r -- -• - '.�l'e 1 ..: ..g viro,^.^�:. {' ...,., .iy ;a,<s+IR`-•tt _.4•,Y .,7 �., s -:� (n .. 4y" .•_:.r-: , -,. i" _• .:... v:.. > l .c. _ .z :. - r :y. ..,i } _ i-- FX•1� �. �1 tt.:. ,� :�a - T - .. .: � _- /p/� a _.•, "'�- � 7`, � : ;� - i � i .a ,�'3 iA is ,_ °.=. � , U : ]- = 'G .-.. r. a 4-w';i`>. ,, •?}..itc 1 `'4?n' - 1 :k �.% - :�__aa ),. -y';': - -, �V : .c• 1 x '{ �x- �t~, 'p i1Rr 7• 3 f -rl .,L _ � Jr ... LJ.._ -... v'.-•...-i ..n.'Y._.A _.:' r_ _+I' v1:-. 4. d.. '� J� e - �1!r �' _ .-�pc� '! _: � .': i �i ELIZABETH STREET/CONSTITUTION AVENUE FLOW PATH I 100-YEAR FLOODPLAIN MAP ""` — °'— ANdER50N CONSUIIINC ENGINEERS, INC �°��- '�t_-3i�__ PLATE T Civil IVulrrRetourCes Enhni.0 gfh25 FULLY DEVELOPED CONDITIONS WITH EXISTING FACILITIES °"' -- — ' Wu0.4[allcgc A.rnuc, Sunc 7u, Fnn Cnllins, C061ti:5 0'c. n. rix - Phnoc(9i0_'?4"01'_O:F-070)226U121 _—o s' 1cc0 00 1 1 1 1 1 1 1 1 I al ;_ ,,;:. u �- efi Syr � �� 4.` S Y i USCuu0u7.J I'U 06/06/02 Photograph No. 1. Looking southwest at the existing west fence along the project site (the north fence is in the foreground, the building to the right is near Cross Section 2135). uSCuuuI3 jpg 06/06/02 Photograph No. 2. Looking east through the parking lot adjacent to and north of the project site (the building to the right is near Cross Section 2135, the building in the background is at Cross Section 1885). T:\OPEN\Cowam01\Cowam01 photos 7&13.wpd ANdERSON CONSUITING ENCINEERSi INC. t* f 1� 01 � r•�2� "� rr - z �. r fz u� ,� t g: {` 3 �.� t r1+ "� S i v �µ.; �, t :^f speh R� 4i a6, lir �w�+ � g a `t `tlJ'� f ✓ �. � y � �'p IP xM � .li, u.7 �"v shy �'� Y= USCUUOUL O 06/06/02 Photograph No. 3. Looking south near the west end of the project site (near Cross Section 2135). :c > i Mill, nvW�''S*S` USC00003 jpg 06/U6/02 Photograph No. 4. Looking east along the existing north fence bounding the project site (the building in the background is at Cross Section 1885). T:\OPEN\Cowam01\COwam01 photos 1&3.%%pd ANdERSON CONSUIIINC ENGINEERS! INC. v Im o o�c�c m I o !o m i j a I 0 u a) � 00 I o Im t y N'• /, r l ;FOP S� .r� ' cc z i� C m A An o OI IL ~I o N U lc� u o in o T m W I m II �4) m y s y2 0 E m m cv m I i i LO I 7 (m+I M (N'l (4) UOIIEAG13 i - l dt oo N I m t I I o Z F % �. L I 'f I m d � t LLB.;:. li) in tv L (n a) K I N Q W >- C CO a �I Y N dl � U cu o II I oo ) T � re F- NI ' N J (u W m c m 0 ] O m O C I I� I C U o I i N i i C/ O cu > I I � e, O co N Oco M N O (U) UOIILA913 I 1 1 1 1 I 1 1 1 I "NO -RISE" CERTIFICATION This is to certify that I am a duly qualified registered professional engineer licensed to practice in the State of Colorado It is further to certify that the attached technical data supports the fact that the proposed_ Ram's Crossing Apartments Addition (Name of Development) will not impact the 100-year flood elevations, ' its on the Elizabeth Street Flow Path (Name of Stream) at published sections in the Flood ` StudStudi, r Canal Importation Basin Master Drainage Plan Citv of Fort Collins (Name of Community) dated Niav 2001 (Study Date) and will not impact the 100-year flood elevations, floo4way-e1eitations, OF floodway wi is at unpublished cross -sections in the vicinity of the proposed development. {SEAL} Attached are the following documents that support my findings: Letter Report for the Elizabeth Street Floodnlain Evaluation for Ram's Crossing w/ attachments (dated .June 10 2002) Sign; Title SUB -BASIN DATA ALL PONDS ARE GRASSED al A4A LAYE12PE0 wxo nEm. n¢FASF r¢smrnox curt n Mm LSM ACES 02 010 01w IM srgWE WTE RAM M'. W MLY6IL 11aRs crs o9Exrrc Sm 9m MAW 1 0.48 1.09 187 4]B 38.2 6088a 0.12 1.4" DU 37.0 1 -3/8" BA 2 0.0)4 O.O 0.29 OJ4 1>4 886 0.0} 1.2"DW 37.9 1-3/8"CA 3 024 D.55 094 2.39 36.9 M44 0.06 1.1" DIA 36.0 1 -3/8" D1A 4 0.126 0.29 0.49 135 36.5 1532.5 0.04 la' DIA 368 1 -3/8" DIA SUB BASINS 1, 3, AND 4 REQUIRE A VERTICAL RESTRICTION PLATE )}'EE DETAIL SH 6 SUB BASIN 2 REWIRES A HORIZONTAL RESTRICTION PLATE 1 SUB BASIN AREA IS DISTURBED AREA BY NEW CONSTRUCTION WaWN FLSTOMC BASIN ONES SHOWN i WEST END OF BUILDGING FLOOD DATA (HIGHEST BFE ALONG BUILDING) 3 BASE FLOOD ELEVATION 50388 yy n 3 REGULATORY BASE FLOOD ELEVATION 5040.3 yS (BEE PLUS 18 INCHES) WEST END LOWEST FLOOR ELEVATION 5043.35 8 ( SLAB ON GRADE) $ LOWEST ELEVATION HVAC EQUIPMENT 504335 2 )EL CROSS- 'TION LINE .r._ - ---- - - -- RICAL) ' 1B85 -------------------------- EXIST BUILDING J293 ... .............................. _� . ....................j _ . NAW WIFD 0 ww I K I. Ruu u VIz Aos -rz s-°sx 4tt'E LON WR 50Jl� y ✓/ Wr i AU 32 01W S1RY (I R[M St A R RAW . Ma J6 J ^ pe9W, -Jr.)4A I I I 7 Si 'I I I ' ' Iro2 ', rroaflaer hmR�� Aw FtFv e 1 fT" •�I rxaWWWI %. ,a �xl -Jew pN. J2.9I�f�;a AU A N3 rr 2s 0Kx" v'lpMW LEI/ ;� RM°Lw.°J ° m-33M NmEi wsre 5039J EPSTJMOf RIM. 755 �yP rW 4 a 13 i I JA+ , I 1. I I I I FJ I I I I -. CUIF OPEN NG ae rayu c I) x _-_ �E m srQPY P2a'NNEW Lk 32I AIX JJ wh-S. J O Adl cn 30 � 1 3) ✓s- o✓rrAu cxs -, R� �\ 3985 SB i#4 _ LEGEND City of Fort Collins, Colorado UTILITY PLAN APPRO✓AL 9A � aTmcc r-r-r-r • i _______1 i ] APPROVED: • ' Pb Fpnw. Lbb EXIST. BUILDING ff."H m 1fD n W rr firs ��. 35.RY N(wc i�Ewe s ' 4'mxR ,rmcN) s A _ _ ..,... °vENMc u„ .. 437 § t .. raL I v(e jn � aid J +., Wt •... I J Jp JT9 �� J AZn 6 V firs nl arc r fir yg L_, RE RCWIRE° N 6E °r�weFAs: N�rrw°GPAa I I I I ` 1 , I I Js � F_J A I I I RrsmRC ew'R4LWr -- 4ri R � "- PROPOSED BUILDING FIN. RR ELEV= 5040.35 ` 1 8 pO o R o b / SB / 1 CHECKED BY.. IbM l MbF.eMVfifiry LbN - CHECKED BY. sfa wM UfPiry N-y CHECKED BY. Pon. A, R4rmfM Cbn - CHECKED BY.: Imlre Engim.r �h CHECKED BY rare yj M a ........................ ..... a........_..s SCALE. 1"=20' _1 NOTES: i. A FEMA ELEVATION CERTIFICATE MUST BE COMPLETED AND APPROVED q FOR THE BUILDING STRUCTURE I PRIOR TO THE RfLFaSE OF THE CO. EXIST. BUILDING 2. A FLOODPLAIN USE PERMIT IS REQUIRED m XF.. J9v ....... •................................................. PRIOR TO CONSTRUCTION ALONG WITH A Lrrsmae aAw rAr j $25 PERMIT APPLICATION FEELij < 0 I ® j I 3. CABLE, AND TELEPHONE LINES C +9 __ ! J J LINES MAY BE REQUIRED TO BE CONSTRUCTION >>1 m RELOCATED WITHIN THE OR IF SHOWN _ r A Wd AREA BY THE PLANS OR NOT IF SHOWN + + EXIST r ON THESE PLANS OR NOT SHOWN. C I Exm. a RCPS c/urc Je d 0 3689 4. SEE SHEET 6 FOR THE CITY O m S A EROSION CONTROL NOTES. Irk y A V / O SB 12 1 5. SEE SHEETS 5 AND 6 FOR V 0 -a 1' SH DRAINAGE. AND EROSION CONTROL ....................I} .................... ..... .. ......, 1 a DETAILS Q i •"-'� rV ...�--any 39 f4 � S ALL DETENTION PONDS ARE TO BE GRASS z .......O ..... .........co y y W y V o i ALL SILT FENCES ARE TO BE i R INSIDE THIS PROJECTS PROPERTY O ..r _ t Jag my 36a Vy" EXISTING FENCESLINE NEVENS IFFESHHO{ CAL HERE Ly z w J0.q,' 4WU` 2A05 -- d5 BEING WTS IDE F w _ MrT x r2 $-0.40t �IRAUPU�my y WICH MSIGV 4W 1qi 414 T. n W o n U W A b c Z ur Y 4 E - ,S I I S: T____ _______________________ _________ .w I r- _ � I_ _____ `•^ A snI rrxrr ---_ r_r Jvs x'rxu cec Aw FTN w4r CUPo raw 45 4}" EXIST BUILDING rr. 4106 1 0 AA. f ` SHALLOW FLOODING AREA Wsrwc eWZW I,e4r .,........ K ousY ti ..` ___________J I c9 rurHn DATE qAI rJCb m SIXET NUMBER 4 of 6