Loading...
HomeMy WebLinkAboutDrainage Reports - 02/08/2017I 1 NORTHERN ENGINEERING August 26, 2016 ' Wes Lamarque City of Fort Collins Stormwater Utility ' 700 Wood Street Fort Collins, CO 80521 ' RE: Drainage Addendum to the Final Drainage and Erosion Control Report for Centre Avenue Residences ' Mr. Lamarque: ' Northern Engineering is pleased to submit this Drainage Addendum for your review. This addendum serves to outline the drainage design for the Arrowhead Cottages project, and to show compliance with overall drainage concepts outlined in previous reports and studies. This addendum has been prepared in accordance with the Fort Collins Stormwater Criteria Manual (FCSCM) and serves to document the stormwater impacts associated with the proposed project. We understand that review by the City is to assure general compliance with standardized criteria. If you should have any questions as you review this addendum, please feel free to contact us. Sincerely, NORTHERN ENGINEERING SERVICES, INC. City of Fort Collins Approved Plans Approved by: Date: �Z, 77 Danny Weber, PE Project Engineer 301 N. Howes Street, Suite 100, Fort Collins, CO 80521 1 970.221.4158 1 www.northernengineering.com ' .V (NORTHERN ENGINEERING Arrowhead Cotta ' The Arrowhead Cottages project is a Major Amendment to the Centre Avenue Residences site plan, previously submitted and approved by the City of Fort Collins. This addendum is intended to document the associated stormwater impacts of the revised site development ' plan on the existing and proposed storm drainage systems. The project area has been previously studied as part of the Amended Master Drainage Plan for the Centre for Advanced Technology (dated February 1987), the Final Drainage Report for the Seventh Filing of the Centre for Advanced Technology (dated August 1988), and ' the Final Drainage and Erosion Control Report for Centre Avenue Residences (dated October 2009). The drainage plan for this proposed project will conform to these previously approved reports. ' Historically, the majority of the site sheet flowed north to an existing detention pond located in the northern portion of the site. A small area of the site along Centre Avenue and Worthington Circle sheet flowed into the adjacent curb and gutter where it was routed to an ' existing inlet at the intersection between Centre Avenue and Worthington Circle. ' The proposed site will follow similar drainage patterns as historical. The majority of the site basins will be collected by existing and proposed storm sewer systems, where the flows will be routed to the existing detention facility. The basin which do not directly flow to the ' existing detention pond are described below: t Basin OS1 is a small basin along the Worthington Circle Right -of -Way. Historically, flow from this basin sheet drained north directly to the existing detention pond. As proposed, the runoff will enter the Worthington Circle curb and gutter where it will be routed north to ' the existing detention pond. Runoff from this basin is considered negligible (0.19 cubic feet per second [cfs] for the 100-yr event) and, therefore, the existing storm sewer system is not analyzed. It is assumed that this slight increase in runoff will not adversely impact ' the capacity of the existing system. This total runoff is similar to the previously approved Centre Avenue Residences development plan, labeled Basin D3 in that report. t Basins OS2 and E are the southern -most basins along the Centre Avenue and Worthington Circle Right -of -Ways. Historically, flow from these basins sheet drained south or west into either Worthington Circle or Centre Avenue Right -of -Ways, where it was collected by an existing inlet on the north side of Centre Avenue. Prior to the Centre Avenue Residences development plan, the historic runoff to the adjacent Right -of -Ways was 0.80 cfs. Stormwater runoff from Basin E will pass through an engineered bio-swale designed to ' provide water quality measures and attenuate the flows during minor�events. This proposed bio-swale will treat a larger area of runoff then the previously approved rain ' garden. Additionally, the total off -site runoff has slightly decreased during the 100-yr event from the Centre Avenue Residences developed site to the Arrowhead Cottages developed site, from 1.9 cfs to 1.86 cfs, respectively. This is assuming no attenuation caused by the proposed bio-swale. Per the Addendum to the Drainage Report for the Centre for Advanced Technology, the storm pipe under Centre Avenue was sized to convey 100-yr flows, however, no supporting calculations are available to support this. 1f capacity is reached at the inlet near Centre Avenue and Worthington Circle, overtopping will occur at the high point along Worthington Circle just north of Centre Avenue. From there, flows will Page12 ' .V (NORTHERN ENGINEERING Arrowhead Cotta ' route through the on -site detention pond. The existing spillway for the detention pond is along the north and adjacent to the New Mercer Ditch. The existing and proposed structures are above the detention pond spillway elevation. The off -site runoff from the ' Arrowhead Cottages developed site are considered negligible to the flows generated by the regional drainage and, therefore, will not adversely impact the capacity of the existing ' system. Stormwater detention is provided by an existing detention facility constructed with the ' Seventh Filing of the Centre for Advanced Technology and certified with the Final Drainage and Erosion Control Report for Centre Avenue Residences. The total impervious area for the previously approved Centre Avenue Residences site plan was approximately ' 48,787 square feet (SF). Through the use of permeable pavers located along the driveway north of building 2, the Arrowhead Cottages site plan results in a total impervious area of approximately 47,916 SF. For this reason, no modifications to the existing detention pond ' are proposed. In conclusion, this addendum has been prepared in accordance with the Fort Collins ' Stormwater Criteria Manual (FCSCM) and complies with assumptions from previous drainage reports. 1 1 1 1 ' Page13 APPENDIX A HYDROLOGIC COMPUTATIONS b �r N _ 1 1 ' North ernEnaineerina.com // 970.221.4158 1 1 1 1 t g r-�v.-.r-lo q por*oo movovIo nE owwor � r,owo00tri ��oo v� o E — m N to t0 � n n In N 00 -:I.. N , � 0 U o C A T a C u Lq n O 00 O O .� IDN O O r n IO d' o tp In rn 0) n o o 00 Oo m to In o m m m o o r` a M m In v n H N o EE 00000 000.-.00.-:-4o00000 m o U c3 2 \0 Q (V ._ W O O V O m N N n O IO n n 0 V N 00 V 0 J >. C C oE 66o000060666000060000 V I� I� t0 00 00 I� N �t 00 N N 00 00 lD m N V M In G Q m U U J II Q O Q cS E C N G p •d Ol f� W N N In .-� O tO f� n to tO V f+ N 00 In V In l0 1 0 T y C ^^ co 00 N a W N N 00 00 D m N V m IO Z N N V Kj 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 _ryryu U ' \ o a m N• M N N N O O C• CD 00 mM M O LO p N C N q 00o0 0000C 0 000000 tO ,O r+M `m p v 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 f+ T O Q R3 C L r j N p O E o w �+ a ` A u j u O O O O O O O O O O O O O O O O O O O O N O O O N 0 0 0 0 0 0 7 V O O O O O O O O 00 N a ij a o 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Z 2 Q o E E o C Z 0 O O O N 0 a u o 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 y O N O O M` m> 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 N " c� O O O O O O O O O O O o 0 0 0 0 0 0 066 Za_ E a Q � E p t n ID O I n O t o t o w w C'^ u O N N O I O N O O d' 00 I n N O O ID ID V cu y 0) 0 0) 0 1 O 0 O) 0 V 0 66 N m A O v �o A Q O O O O o O 0 O 0 O 0 O 0 O C O O 666 O O O O O O O O 1 C O— O 0 O 0 O 0 O 0 I O 0 W U O C U w y G` I u O O •� C N 0 •-+ 0 f-+ 0 to — '-+ O O O O O O 6+ 0 0 N W N C N t0 O O 1O o u c:� O O O O — 0 0 0 O O I Il 00000000 OOOO OOOOOO 000 Q f j W \ N Q o = O 0000001000 0 0 CA 0 0 0 0 o C o o o a m s u o 0 0 0 0 0 0 0 0 0 0 0 0 00 00 0 0 00 o ¢av o000000o0oo0000000000 O E o N > N � A O _ d LAJ O Q V OomO 0 mr Ql G � � c � 0m0LO 00000�--�0000 00-0m0mIn olOm•-+10 W �0� V J ;m o � Q d W QW �" c/ E Q V ovm00-tl V �T O V MmmMln WADO ntOMu-)�a m O M'�l Q cv W NO IlOO ornNN(O c»Nm io .-. �o v LI).-+to�m�v_Inrncd m G s •m .-... N .-+ N m.-..-..-. 6 .-. m C N 00 .y V O Y m N LL TO O a ry W A m L> ,fin U a C N m V In t0 f, m 1 N m V 1O U 0 W IL _ m < Q y� p, CO CC •N aaaaa¢aammmmm (J 0 (N 00 U � U NU m _ -x t 3 U V) �3 �l Q n m R c o 0 0 0 0 0 0 0 0 0 0 o m o 0 0 o M o N „ o ~E Lo miti���u'i ui u-i �o Sri ui iri�oi iri of c O�O00000m000w000m? om $o c c u o�.E �iri Niri iriM�Min Zvi 6 66 ui uimmui of 0 o O N S O d n N s y N E_ T C O in 0 0 0 0 0 0 0 0 0 CO O O O m N O 0 3 m E iciiriirinn ui 1-� rv~ ¢ o ¢ o y m m R p C O c F E M 000zzzozzzzoozz,znzM N O Q Q 4 N Q Q Q Q N M Q Q N 4 4 m a o .q u A CO V n 0 0 0 N O 0 0 0 i n a 0 0 0 0 n 0� n U ; tO CO m OOO a 0 000 M cO 00 in O l0O N O y N' M O O O N 0 0 0 0 m t o O— O o o l LL d A 3 N W O N� n 0 0 0 0 c 0 0 0 0 0 0 N O 0 0 0 N O n C M L O O O O N O O O OM. -. O O O O O O IA L U J F � N 0 o 0 0 N 0 0 0 o m� 0 0 0 0 a 0 0 N N N y J Q ~ ti ~ E Z Z Z Z Z O Z O Z Z- Z Z O- Z N Z Z Z s ' u ]1^ 0000in O O O O O oinoo.-+oO-.oOq O O OO d' O O V- O - 7 0'D0 000 � LL 0000— 0-00100-+N O —00 O O > w ^ 2 O QQQ O O N o O O O O O O O O O O Lq o o t n O O O O 00000000000066,06000 Q o11 Y LM J 00000`n°o`n000�oo,°n°on'o a a■9pC ,; ,; ,, ,, C �^" 110 00 LAJ /Z� 1«�� i0M V in O m NOS aO OO m O 00 rlq NtO W u O X iCOm 0+ 0 0n00 N UO LLI N 0 ENL6 N m N, M 6 M N 6 NN0— N m z _ O yQj p iYl _�, C O m c0-+d' OM M n'+v7O N V mot -+c0 W 0- 0 Y Y 0 La "�� W ONMMOM mMl0000h0 o m A O N In tD N �[J V N N m 1 N� N N Q N Z O LL c t C�J N '� Nm(a�l V V am�MNN��NNNOInOm y y J O � LYc�` m m Vv v 1wOO.-:noOoOTmn o o n m OOOO nn an iinn U 000 ocn .:00000 Er O TO LTG a, n W NNin ONnnNlO 'Q N 00 i!1 O N o J t O ti a n n l0 DD W n N a DD N N CO m uJ mi m N V M O v II 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 W � 0 o (4� lS TO MICOINNO-0 n nn Nc0 V Nw U� d ' U N Gn 0 0 n 0 l0 0 m 0 mnN 0 0 0 4 0 c0 0 N 0 N 0 m m 0 0 t0 0LY m .. Nvm q 0 0 C jF = N M GO O 0 V N b V ( C/]O O 11 II ; O J'O O Z O Z O Z O Z O Z O Z O Z O Z O Z O Z O Z O Z O Z O O Z Z O Z O Z O Z O Z O Z cr o E „n .� m H o f O J ILL li LL W W W C a to n O1 N M V N LL(JNN ,� N e 00 m 3 ppA Q QQQ Q < Qammmmm�ow 00 m> 1% ry A O ~ C7 fN = 3 m + > m .c N 44 ma 4 4 in0 4 4 nro 4 Q m Nmv�n m m m m �Ow w MO JONON `m m O t4 H H>> i y p a o In LO r O 00 In io N ID CO V , m m Ol o N V m In to N 00 a0 V (V <t '-I M L—y G7 0 0 0 0 0 1 O O O O '+ O O O m N 0 0 0 3 p 0 W V OO o 0 Ln lD tq V f+n NOl o yJ o Nam o0 0o m n no? o� LLCY 0OOOOOOOOOOOOO 00000 m iO o U N 01 N N 10 � O 00 ID �t W mw 000 d' 00 .-I q M 'V w O 0' 0- ,l + O O 0 M O 0" M M a r+ O O 3 o 0 0 0 0 0 0 616161610 0 0 0 0 0 010101 � o0 ¢ o ¢ J m Q1 n ° .` : n Lo n in Ln Lo Ln LD LD Lo Lo Lo ,-� m Lo Lo 0)M m m c a 0 c St m.- ? m of m m m m rnrnrnrnrnrnrnrnrnrmarnrnrnryomO moim Dimoi6 mrn Dirn Di n06 Di06 m c o — u m V • c_ � n oa n o0 00 00 r m 00 00 n 00 n 00 n oD n oo I\ moo n n m� V h m w m n m Ol M m m o� � m ;;' a v v vavavvvav�vvvmmvm c In Ln Lo In InLnLoInlnLoInln0LoLoLo00o o 00 00 00 00 00 00 00 00 00 00 00 00 lD 00 00 00 Ot m 00 N N N N N N N N N N N N N N N N N -4 N N N O O C O ti d o .-+ O) h O co 001" I m 0 1N00��--i Ln V 0 In M m h o O w MLO o M m O OI 'tmn't o O M O N N r 2 tirl Hr�F /O� V Hly■ � • ryQB M p Ol h W N N Ln O In In 1D cq— N In V R <t -t I, nlD W w OD � '� ;� w NNCO�ID M Nd' M 0 0 w � U O O 0 O o 0 0 0 0 0 0 0 0 0 0 0 0 1616161 2 u m h w N N In '+ 0 In In LD V .-a N CO In t In OO V - � t` rlD CO CO f�N�00 N N0000 to m N-4m o 0 0 00000006666666000 W O 00, � W . �^ S"N Y4 m T C OOO omON ; 0 ~ '� OOOOOOOOOOOOm '� ■ N . N .� 4 In lP In IP In Ln In IIJ In III In Li l0 lC1 L(1 ll) 0),IP 0)"Ypy n .Ni Q o � M Z y W U � r c_ O Ln O OOOOOm OOO� OOO mLnO01 y U C M E In ui u0 In Ln to In In to Lo Ti W to In In .m-+ O- In Ot m N N o In o 00000M000cD000"?Lnorn c N ~ E LP IP IP IP Ti Ln LP IP � ui Ln In to ui ui In (n In Ql E 0 N _ Q n c V M Ln 't t\ r 00 m d' M In 't 0 W OD 0) -;t M M rI � �m o0000000000000000000 !OLL O U N U O i1 n LL v i N M �ln to 00 Nm d' In U� W LL(:3OO N fi ¢ ¢ ¢ ¢¢¢ ¢ <m Dom m m W tii _ c �(�� N m v o x 0 V N N C T W +`� c C c o v Vr E o II C C C Q Q Q¢¢¢¢ m m U O W li C7 E c W a ¢ 0] ONO m O O O R LL II I 1 i APPENDIX B HYDRAULIC COMPUTATIONS noineerina.com // 970.221.4158 I 1 1 1 1 1 t I 1 1 1 APPENDIX B.1 STORM SEWERS Y';2C - Yrlorry Hra4 'North ernEnaineerina.com // 970.221.4158 I tT: E i 11 1 lit C W 1 E ramn 0 u ro F c c c c c Z Z Z Z Z 0 N n N 'Am c C 0 C W N M m Ln N G J Z c W � CR 0 0 0 c_ aW (.D� (D (DD S n O O i0 0 O c q rL C O O o O O O O O O U) GOD ONi O O J C7 a ^ ui ui ui (C (C 4i m = 7 Lf) Ln U') N Ln O a on CD o 0 a c J Lei tr ui g sC g 0E a 0 O^ Lo o Li W W uoi Z S In 0Q4 a v a I v C v e N O N O N O N O N O n agG n C 1 N O n O r D' 3 a a g C JLu nrl� n n N O N m � �J 0 g LO _ W Ln 'n r o m m to o o Ln co Ln 0 Jm �^+ V O N a V O N 0 C U U U U U J Lf0 N (N co co CI 0 C N C m O fA J co O 0 N LL V N N O CDV LM m L N } 0 E N m c W O J N N N N (N.. 'C a 'a a a 'a a y LL N W ~ o z m c d J Z .1 N c 'CL E 4) 70 L` 2 p m C m f+1 O O O O O O O p �^' 0 0 O 0 O J Y 0 0 0 to >1 ON m O O O N o a0 o O N C 'A -� w 0 O O o O O n N .w LO m L o o co O co N V m a N o 0 0 0 0 0 c n rwi 0 to r°Di � ago m o N 0 . J> t7 m ^ v LO V v v v w m n w toi LO In v w v o 0 m — — 1 o 0 o L O O O O b N CD 1� Nocc N > P9 N N C) O O aD O V N W) m m o 0 0 0 o E z z Cl) m m m m p 0 0 0 0 o I- f0 O CO N O N O N O J > N ui N Co 0 . S m O O O O O Ip LO In 1p 1A In 0o Cn N o I� 0 > 9 gg 3 m Ln LO o O !O rn f0 O O LO m LO O L V V O O N J V a N M N N n O CO�1 e N O O y e 0 0 o 0 0 m m CD o 0 J> LO v v v v v W m N N N N p h � O o co W UN Cl COO j v N N o 0 L C m N o Q Cif OQ O O O O O G L p o m m m CR 0 0 o O o G v - n COO O o J m r 2 m BOO to N LO U r m W O O > `r v a v c m C3 LO CD LO LO LD LO E 0 a N I I ao to O o O ao N O Q U N N O O p — m y II m N N N m m LL N C15 U f/1 m II O U ID C N (o V N - d J S 8 S o 0 0 o o o 0 in Ln u0 w Cl) lnO B9 9 :ul 0 N O UI 1nO 60 i : U, p g rn ul lnO 08 Z :ul 0 m o� U U7a) of O UI inO L9' t'U' 0 m lomml I= J c� W O N J O = UI J�'AU, Jill 08` 3VO9 13 PUJE) Ilepn o - g o 0 0 o g _ > o a o Go o g Ln w i I 1 1 1 1 0 0 0 0 o g Cl Cl to 0 o� 0 n 0 m cu N a) g 1n0 WS409 '13 'AW 9E L1709 13 .PUJS 4 :ul - S£0'4£+0 e1S O J N - W h O � J S U1 ZO'5409 '13 'AW 1r0 ZO'S40S '13 'AUI 60'L40S '13 'PwO 00'00+0 e35 I _ _ o I I o 0 0 0 o i m 4f N 0) to Nf CD ud) L W I i c la IC.) la 1° a to J9 w to F L. O O 1.N = 'W L 13 CD co IE L 3 m L 1� co O m 0 Z I � I I I I I I I I I k. LO a!Z . « OD } k �\£ � E JkOD 3 »£ \ \ . 46 k 00 2 \CR A� kLu ° co \ kL£ :32a. ® !t o . E � LoCL � E j � \ W 2 . .ƒ §z - w I 1 1 Q E IP- m C 8 � u m W O C Y m L m \ O O CD Q o c S y e 0 O C� W m E m m c m ci — m a co o E z L '+ Z S 00 q m G � O Go J Ole m e 0 v m o _ m 0 rn c J °D CQ N 0 w o fA o 0 C N to m 13 17 W � co M v Go N Q N O O O a00 x f rn Cl. m C) ^ C� d S m U _ �U n II c m � E t N d N E m v O 8 8 y :E N U F N _ LL ._ m m � m O J I i 1 1 1 i i 1 i 1 Jbi o O O O O O on g 0 W m 0 0 m O L f0 d 0_ O O 0 - - _ 1n0 04'"og '13 '^UI OlrLtOS'13 PWJ L :Ul - L6B'£Z+0 EIS p N w II ' o x UI LC£bOS'13'^UI 4L'"09 '13 'PUJO IIeAnO - 00'00+0 eLS L -- o N 5 0 ri � o o g q g Nh LO 0 U) W I s rn m c `o m E z z m O � N E N a W bi iTL d a` I 1 1 1 1 I 0 u m c a 7 >� 7 H m c m c m C m O m c m c m C 'O m C m .. c O Z O Z O Z O Z O Z O Z Z O Z O Z � N N m m C C O c W r- N M M m m (V 4: 0JZ c o v m � � cmo m rn 'o J C Lo ava�a� v' v Lo U)U)� LOmLn U) C O W m N N T7 O O O O O O c o C O O O G O C O r O N 00 'at 1D I,- m to (D a O) J V ui �vpti ui - ici ui ui vi � - ip = 7 � N � C Ua D LO LO 100 100 O m It R (DD • � X m f CD R (DD R IT a J 3 O It O o O G O^ n n 0 n C0 v> n D D O Z SG m N N a 01 W 0) O ccoo N O. a M N OD O? O O C O O O G O N O O J flJ OD ccp N N q Oai N N N O O aa� O C J _ W O O Ln LO0 r0 tmD N � N fOD N M N c m � M aa Cl) a C> a CD eNy V a O > J CW �+ O LO � � of � � � iO u> m m rl 'D v o n `n co m a cO O a, .- M v N t` c c- J m � m < OD fD n M ry r vi N r.� N N a o a C U U U U U U U U U J � C m LO m m U) m U) N U C N O c y J m N W a ate' N CO w Ln r _ LL r c7 O O N O O m (0 N o E n m D 0 c M C J N N N 0 N m O a n a c c n 'a a h an w ) H o O m a z J z 1 1 1 t 1 cCW W N O O O O O so �^+ C O 0 0 O 0 0 O O O) O O O (O O O O J .- O r r fD O O M p W N CO N O N N fp W c N O O O O O O O N W Or 0 0 0 0 0 0 0 0 Y fn OO NO NO MO 9VOPO MU O Cl) N le O. O O ON O O oN O 0 C O N O V_0) O m a M � O M N O O O O O y r, 0 C) o 0 o 0 0 o 0 O (0 n n ED ((D Ih v J > Le) LO Ln N )Lc; vi N h CD OF a O O O N a 9 a afn O lot W W In In In In to In In In fn •O Cl) 1 N N Cl) CO M W M 0 N 0 0 7 0 O 0 O o O 0 O O 0 i t O O E �+ fND co Irn n N m n cro m m mW M N N r• C O C « O 0) N N in In M (n M W O !D S fn N M M N M N r O O E z L i N O N N N O Z p, fro fro CO o o o r N V fv n fN0 1r0 c(D v gym_ a g 9 o g aOD N rD aa) N aO Cl) N > m ^ g aaC-4 O O O r r co N N r OD O In fr0 C cMD O a 01* (M It N W J (n qw GoO f0 fr'7 M N N O R O O M N N I M V 0) W N O M co aD N M O M N V O 7 O S O y e 0 0 0 0 0 0 0 0 0 0) M fn n n (O, cro a fn to fO fn f0 Iapn 1apO n LC)� m Ln fOn Lc) In fn LC) W m Cl) M f0 M M. N O O O O O O fND ((O r n N � n M W II E < M N N O O 9 Gm d _ O) N N N (O M N M 0) W C ` Q 0) - N M M N M N r II O O p, N N O •V CND (O (0 (O N N 00 O O '7 O f0 Cl) r O f0 CD fO CD (D O '7 L gym^ i o o a 8 g 8 x W ci fn N to In In (n In f0 cR 0 O � M _ (0 Oi (MN fOD N M' N U > gg c m (n N O N N (n N N h ,E o N W N T7 (I N O N (P r M W W o V IT v m o 0 N O O O W h L n 00 ' in O OLn O ' CV V W N LL s W C N N l0 O C � N M a N (O r Go 0) 0_ Z J _ 0 0 0 0 0 0 0 0 0 0 to LO Ln LO N 1no N Ol $ :U 8 N ul inO Z4 n 9 :ul ul 3n0 SL £ :u 0 N ul 1n0 cu 6l of Z :ul 0 n ul 3n0 �i 6L' w :ul N J i� S ul o0 IleAn 0 o o g o g v 0 � 8 y40 Lo in LO W it 8 0 o Opp aO aO O O O O o O i 8 O W O O O A f0 L_ O L O U f6 Q7 !Y O Y M 1n0 96'440S 'l3 'nul l9'L40S '13 'PUJO S _Ul - LOT LZ+O elS c W ul09'"0S'13 nul 1n0 09'"09 '13 'nul £911709'13 TWO o 4 ul - 999'£0+0 elS — — — ul £9'9405 '13 'nUI 3n0 4Z'"OS '13 'nUI 8LIVOS'13 TWO 00'00+0 elS o 0 0 0 0 0 O LO p Ln LO LO W 1 1 1 `IJ 0 o 8 o 0 0 0 1 S 8 0 0 La LO %n 0 cm m 0 m O L U cc d Q' a 1n0 SS'"09 '13 'AEI LL'LYOS '13 'PwO L :ul - Llb'LZ+O e39 N J ' W J � O � Q J � x UI 0£'"09'13 'nul ln0 8Z'"OS '13 'AEI Z4'L>OS '13 'PW°J 00'00+0 elS 0 o 0 > Ln U 0 n 0 LO 0 L 0 W U) a J 1 i 0 0 0 0 0 0 0 � O m 0 m 0 0 to N 3n0 LZ'4409'13'^W 00*MS '13 'PwO 6 ul - 9L'01?+0 e1S g eon N O O e N J n J W O m eJ 7 S uI OZ'"09'13 '^UI 1n0 ZL'4b04 '13 'nub 6L'9605'13'PW9 00"00+0 e3S _ o �p O co LO cV LO W u 1 0 N 47 N N N C O E Z E N E ti ai LL V O d c 0 5 m' c a H c O to Z o N N W ME C f` coo CJz w ui O c J c V W c m e N _ _ m O v, a c E z C xc� m LO c 0— r' :3 f0 C a m� v C ly� ro OR m G c w Ln � In O C C ^ m J m � m U c to J WW 00 C N C J 0) G. LO G E N I I C m O J v p t N a O E n h o IL ui IL Oi � w H 0 z W d c p J 2 � � I I I I I I I I I § d\ i . co /�\ \ ) � ° &■r G 2 � i B _ 2 k W0 I)£Ci ® | ' $ 04 ) coCi z . 2 £ � CD \ S . k�£ k Ln !£ + . m / » §�£ k E 2 $ ED ! f & a g a £ . . -J4£ k } . k«£ k $ .. k { k \ °LL { \ ` k 3 R } ,7 ! ). I [] 0 0 0 0 0 0 Ca in a e U') 0 0 0 rn low 0 0 m O L LO t1 fU N 0 3n0 L9 EPOS '13 'AUI o L9'LYO9'13'PWO O1 C4 t ul - 690'81+0 e3S 0 o uI E8 0405 "13 ^UI t17'9009'13 'PW°J IlepnO - 00 00+0 e1S N 3 d E 0 rn I 1 1 1 APPENDIX B.2 INLETS noineerina.com // 970.221.4158 a n N m E c E o V � W W K Y � LL gtiu.-iooanidC516m �"� N 10 !II lG w m n 1D rl m o O UI N � c 0. avmo om w am O ui oo a ni o o o ni .+o 4 n e O W ft a V m U1 t0 N .i .i Alt CQ C ~ ti .-I O ti 0 0 m 0 0 w M M O to O O N -t m Y W LL U O o 6 0 0 6 6 0 6 6 6 6 6 N v a3 3 a a a a a a a a a a a a a a CO �.% LL Q Vl IA Vl Vl Vl Vl VI Vl IA Vl Vl V1 VI F {i W J Z L° L° m L A Lo A La m o l7 l7 l9 U' U' U' l7 l7 l7 l7 c c c c c c c c c c o 0 o 0 .. 0 0 0 0 0 0 0 O D D p 0 0 0 0 0 3 3 3 3 — c 3 3 3 — c 3 3 c 3 W 4 C C C C C C C c c c E c C E C c E D O O U C A D A O U N O. U C O p` p` p N N N N N tO N N N N N N N N N N N N N N a 0. a a a a n a s a 0 0 0 0 0 0 0 0 0 0 z' z' z' z' z' z' z' z' z' z' 0 d H Z N N N O d w N N N d w N N d 00 ill G .� rl rl •i N C .-1 rl .i C rl •i C e� N Vf N 1%1 .-�N..�qv+.. .. m M IYI m WZ N o c Z Ci rii 2 ru ru J ,ri J Li J ri J L J q v Z Z X X Z Z Z _ 2 Z Z _ Z _ 2 — l0 x W W _ _ II m ciI W m v @ o p m C a` y a Q M Q Q Q Q m m m p w m U w p MEE ME MELIMME MERIMEM EMEMEMEMMIS MMMMMMMMMMM MMINSOMMIMMOM IMIMMINIAMEAHILE-110M mmmmmmmmm INMEMONIMMIlmill O O s s O (sp) Apedeo 1 1 1 1 1 1 1 1 1 1 1 1 1 1 i ki M malmmm (s}a) /liaedeo miummm MRIMMM malimmm malmmm mmmmml MMMLMM Em MMMILIMIFI a 011.0 NFISM MMMMLMRIIRIM O ep Q pp O �! ry M uo � a W .E- J C a. Z c c X M! W o maim ENERIEll INIENEIIE INEENININNINE INIENEEINIERILINE IIIIIIENININ INEENSIERi INEENEINEININSoWL INIENEEINNEINININOB INEENEIIIIIENIENE INEEINNEENEIII m g o 0 0 0 A to �ti (s;a) f4pedeo INLET IN A SUMP OR SAG LOCATION Project = Arrowhead Cottages Inlet ID = EX INLET 3.5 (Design Point A6) •f-Lo (C) A H-0urb H-Vert Wo Wp W Lo (G) in Information (input of Inlet Kist Type I Depression(additional to continuous glider depreaslon'a'from 'G-Allow) a,,,w car of Unit trials (Grate or Curb Opening) No r Depth at Flowline (ouvi de of local depression) flow Depth dndomutbn in of a Unit Grate L, (G) 1 of a Unt Grate W. Opening Ratio for a Grate (typical values 0.15 0.90) A. ling Factor for a Single Grate typical vaue 0.50 - 0.70) Cn (G) f Weir coerciciav (typical value 2.15 - 3.60) C. (G) i Orifice CoeeicieN (typical value 0,60 0,80) (G) Opening Information In of a Unt Cub Opening Lo (C) x of Vertical Cwb Openrg In Inches H. A of Curb Orifice Thmad in Inches He.m of Throat (see USDCM Figure ST-5) Thne Width for Depression Pan (typically the guner width of 2 feet) Wp )ing Factor for a Single Cum Opening (typical value 0.10) CI (C) Opening Weir Coefficient (typical value 2.33.6) C. (C) Opening Onfice Coefficient typical value 0.60 - 0.70) C. (C) al Inlet Interception Capacity (assumes clogged condition) 0. Capacity IS GOOD for Minor and Malor Slorms (,O PEAK) Orewuauneo MINOR MAJOR CDO7)Den er 13 Combination 2.00 Inches 1 6.0 6.0 fiches MINOR MAJOR 3.00 feet 1.73 lost 0.43 0.50 0.50 3.30 0.60 3.00 6.50 o 5.25 0.00 2.00 0.10 010 3.70 0.66 MINUH MAJUH EX INLET 3-5 (Design Point A6).)Ism, Inlet In Sump 5131'2016, 8.31 AM 00 � a A 'o H a. W = J °J Z N d _ o t ft no IO G ry a0 ID ci miummm MLRMM maimmm 2 MLMMM MLRMMM MILIMMM malmm maimm MMLMM MMLUMM MMILUMMMMM mmalimmm mmalmmm mmmkm mmmallmisal MMMMILMMIKIN MMMMLMRIRI MMEMOMMUM mmmommomm MMMMIMMMINIL- 7-1 IM-M MU d rn A O � � M � T M m cD I I I INLET IN A SUMP OR SAG LOCATION �l Projects Arrowhead Cottages Islet INLET 1-3 (Design Point B3) H-Curb H-Ven We Wp W Lo(G) on trtonrmtion (inputl Of Ihim Inlet Type, I Depression( additional to continuous gaiter depression a: from'C-AIbW) alp' �r of Unit Irtets (Grate or Cub Opening) No r Depth at Flowlne onside of local depression) Flow DepM a lofomatlon in of a Unit Grate Le (G) t of a Unit Grate W. Opening Ratio for a Grate (typical values 0.15 0 90) A., 3irg Factor for a Single Grate (typical value 0.50 - 0.70) Cn (G)' Weir Coeffkiert (typical value 2.15 -160) C. (G) ,Orifice Coefficlea(typicalvalue0.60 0.80) C.(G) Opening Information to of a Unit Care Opening L. (C) t of Vertical Curb Opening In niches H,a. I of Cub Orrice There In Inches Ht.af' of Throat (see USDCM Figure ST-5) These. Width for Depression Pan typical the gutter width of 2 feel) Wv Sing Factor for a Single Cub Opening (typical value 0.1 Of G (C) Opening Weir Coefficient (typical value 2.3-3.6) C. (C) Opening Orifice Coefficiert (typical value 0.60 - 0.70) C. (q. al Inlet Interception Capacity (assumes dogged condition) Q. r Capacity IS GOOD for Minor and Major Stones (>O PEAK) Citednptlul MINOR MAJOR CDOT/Denier 13 Combination 2.00 Inches 1 6.0 6.0 inches MINOR MAJOR 3.00 - lest 1.73 set 0.43 0.50 0.50 3.30 0.60 3.00 ",r, 6.50 50 5.25 O.DO 0 ua 2.00 e.of- 0.10 0.10 3.70 s,o 0.66 nit Idles char agrees iet INLET 1-3 (Design Point B3).tism. Inlet In Sump 5J3112016. 8:33 AM r L U T d m U N C N a.+ N U C n 0 0 N r N f0 Q O T Z mm MMIMMLwm6mwm MMILNMLMMMM MMIRNMINIMMM MMMIMMIMMM MMMLUMM-MM .,I- in MmmLvmffr mmmalml imilm MMMMLMMLM MMMMEIMILIVE MMMMMIMMIM MMMMMLMMLM mmm miumm MLumm maimmm mallmml maimmm mmkmmm mmkUmm MmLummmm mmallmmmm mmalmmmm mmmkmmmmm ry o m (s{a) IG�aede� INLET IN A SUMP OR SAG LOCATION Project = Arrowhead Cottages Inlet ID = INLET 2-1 (Design Point C) .�Lo (C)-� H-Curb H-Vert We Wp w m arlandii (trait) of Inlet Inlet Type Depression (additional to Coranels gutter depresslon'a' from'O-AIbW) Bm wof Unit Inlets (Grate or Cut) Opening) No r Depth at Fbwee (outside of bral depression) Fbw Depth r FdormetIon b of a Unit Grate L. (G) f Of a Unit Grate W. Opening Ratio for a Grale (typical values 0.1550.90) Al ling Factor for a Single Grate (typical value 0.50 0.70) G (a) r Weir Coefficient (typical value 2.15 - 3.60) C. (G) Onfice Coefhciert (typical value 0.60 - 0.80) Co A opening tdcrmi In of a Unt Cum Opening L. (C) f of Vertical Cum Opening in Inches H. t of Cub Orifice Throat in Inches Hp r of Throat (see USDCM Figure ST 5) Theta Width for Depression Pan (typically the gutter width of 2 fee) Wp ling Factor for a Single Cum Opening (typical value 0.1 O) Cr (C) Opening Weir Coefficient (typical value 2.3-3.6) C. (C) Opening Orifice Co9Hlclea (typical value 0.60 - 0.70) C. (C) it Inlet Interception Capacity (assumes clogged condition) 0. 3apaclty IS GOOD for Minor and Major Storms (�O PEA ) Oasiansalnsa MINOR MAJOR nch 2.00 ies CDOT/De W13Combinatlinchas 1 3.8 3.8 Ileet MINOR MAJOR 3.00 1.73 feel 0.43 0.50 0.50 3.30 3.3U 0.60 okO 3.00 3 00 6.50 6.50 5.25 52F 0.00 0.00 zoo 0.10 010 3.70 0.66 Bet Mines MMs legrees Bet INLET 2-1 (Design Point C).fdsm. Inlet In Sump 5/31/2016. 8:34 AM w 'o ~ a W J °1 d _ o N I Ell APPENDIX B.3 SWALES AND WEIRS 1 1 1 1 1 1 'NorthernEnaineerina.com // 970.221.4158 Channel Report i Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3D® by Autodesk, Inc. 2' Sidewalk Chase (Design Point A2) Rectangular Bottom Width (ft) Total Depth (ft) ' Invert Elev (ft) Slope (%) N-Value Calculations 'Compute by: Known Q (cfs) 1 Elev (ft) Highlighted = 2.00 Depth (ft) = 0.39 Q (Cfs) Area (sqft) = 100.00 Velocity (ft/s) = 2.00 Wetted Perim (ft) = 0.013 Crit Depth, Yc (ft) Top Width (ft) EGL (ft) Known Q = 0.17 Section Monday, Aug 29 2016 = 0.05 = 0.170 = 0.10 = 1.70 = 2.10 = 0.07 = 2.00 = 0.09 101.00 1 100.75 ' 100.50 100.25 ' 100.00 1 99 75 ' 0 I 1 1.5 2 Reach (ft) 2.5 3 Depth (ft) 1.00 0.75 0.50 0.25 M -0.25 Channel Report Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3130 by Autodesk, Inc. ' 2' Sidewalk Chase (Design Point D) 'Rectangular Bottom Width (ft) = 2.00 Total Depth (ft) = 0.39 Invert Elev (ft) = 100.00 Slope (%) = 2.00 ' N-Value = 0.013 Calculations Compute by: Known Q Known Q (cfs) = 3.81 ' Elev (ft) Section 101.00 0 .5 Highlighted Depth (ft) Q (cfs) Area (sqft) Velocity (ft/s) Wetted Perim (ft) Crit Depth, Yc (ft) Top Width (ft) EGL (ft) 1 1.5 2 Reach (ft) Monday, Aug 29 2016 = 0.31 = 3.810 = 0.62 = 6.15 = 2.62 = 0.39 = 2.00 = 0.90 2.5 3 Depth (ft) 1.00 0.75 0.50 0.25 -0.25 APPENDIX C LOW IMPACT DEVELOPMENT L iJ 1 ' NorthernEnaineerina.com // 970.221.4158 II 1 I 1 1 1 0 Design Procedure Form: Rain Garden (RG) Sheet 1 of 2 Designer: D. Weber Company: Northern Engineering Date: August 26, 2016 Project: Arrowhead Cottages Location: North 1. Basin Storage Volume A) Effective Imperviousness of Tributary Area, la I, - 100.0 q (100% t all paved and roofed areas upstream of rain garden) B) Tributary Area's Imperviousness Ratio (i = d100) 1 = 1.000 C) Water Quality Capture Volume (WQCV) for a 12-hour Drain Time WQCV = 0.40 watershed inches (WQCV=0.8' (0.91- 1'- 1.19- Iz+0.78"i) D) Contributing Watershed Area (including rain garden area) Area = 3,259 sq It E) Water Quality Capture Volume (WQCV) Design Volume VwcCv = 109 cu ft Vol = (WOCV / 12)' Area R For Watersheds Outside of the Denver Region, Depth of ds = in Average Runoff Producing Storm G) For Watersheds Outside of the Denver Region, VW WV o ER = cu ff Water Quality Capture Volume (WQCV) Design Volume H) User Input of Water Quality Capture Volume (WQCV) Design Volume Vwocv uses = cu fl (Only t a different WQCV Design Volume is desired) 2. Basin Geometry A) WQCV Depth (12-inch maximum) Dwocv = 9 in B) Rain Garden Side Slopes (Z = 4 min., horiz. dist per unit vertical) Z = 4.00 ft / ft (Use "0" it rain garden has vertical walls) C) Mimimum Flat Surface Area AN,,, = 65 sq ft 0) Actual Flat Surface Area Aft„� = 71 sq ft E) Area at Design Depth (Top Surface Area) ATM = 289 sq ft F) Rain Garden Total Volume VT= 135 cu It (VT= ((AT. + Ax, w) / 2) ' Depth) 3. Growing Media Choose one QQ 18" Rain Garden Growing Media O Diner (Explain): 4. Underdrain System A) Are underdrains provided? Choose One O YES - O NO B) Underdrain system orifice diameter for 12 lour drain time 1) Distance From Lowest Elevation of the Storage y= 1.0 it Volume to the Center of the Orifice ii) Volume to Drain in 12 Hours V0112 = 109 cu It iii) Orifice Diameter, 3/8" Minimum Do = 2/7 in LESS THAN MINIMUM. USE DIAMEI P' 11 374-018_RainGarden.xism, RG 8/29/2016. 12:07 PM APPENDIX D EROSION CONTROL REPORT I! II I' II � II 1' II !1 North ernEn aineerina.com 11 970.221.4158 1' ■� I NORTHERN ENGINEERING Arrowhead I I [Il I Lei II I' EROSION CONTROL REPORT A comprehensive Erosion and Sediment Control Plan (along with associated details) is included with the final construction drawings. It should be noted, however, that any such Erosion and Sediment Control Plan serves only as a general guide to the Contractor. Staging and/or phasing of the BMPs depicted, and additional or different BMPs from those included may be necessary during construction, or as required by the authorities having jurisdiction. It shall be the responsibility of the Contractor to ensure erosion control measures are properly maintained and followed. The Erosion and Sediment Control Plan is intended to be a living document, constantly adapting to site conditions and needs. The Contractor shall update the location of BMPs as they are installed, removed or modified in conjunction with construction activities. It is imperative to appropriately reflect the current site conditions at all times. The Erosion and Sediment Control Plan shall address both temporary measures to be implemented during construction, as well as permanent erosion control protection. Best Management Practices from the Volume.3, Chapter 7 — Construction BMPs will be utilized. Measures may include, but are not limited to, silt fencing and/or wattles along the disturbed perimeter, gutter protection in the adjacent roadways and inlet protection at existing and proposed storm inlets. Vehicle tracking control pads, spill containment and clean-up procedures, designated concrete washout areas, dumpsters, and job site restrooms shall also be provided by the Contractor. I' To ensure stormwater quality is achieved long after the construction of the project, one permanent Stormwater Quality BMP is included within the design. Located at the northern portion of the project site, an Extended Detention Basin (EDB) is being proposed. This I' measure will treat all of the runoff draining through the property prior to reaching the historic outfall. I I I I I The Final Public Improvement Construction Plan contains a full-size Erosion Control Plan as well as a separate sheet dedicated to Erosion Control Details. In addition to this report and the referenced plan sheets, the Contractor shall be aware of, and adhere to, the applicable requirements outlined in any existing Development Agreement(s) of record, as well as the Development Agreement, to be recorded prior to issuance of the Development Construction Permit.. Also, the Site Contractor for this project may be required to secure a Stormwater Construction General Permit from the Colorado Department of Public Health and Environment (CDPHE), Water Quality Control Division — Stormwater Program, before commencing any earth disturbing activities. Prior to securing said permit, the Site Contractor shall develop a comprehensive StormWater Management Plan (SWMP) pursuant to CDPHE requirements and guidelines. The SWMP will further describe and document the ongoing activities, inspections, and maintenance of construction BMPs. MAP POCKET ' DR1 - OVERALL DRAINAGE EXHIBIT n Enaineerina.com // 970.221.4158 TECHNOLOGY ISTH ATRIX LABORATORIES 1ST OWNER: TFARMA (CO) QRS 16-93, INC CENTRE FOR ADVANCED TE'CHNOLOCY VTH OWNER: MONDAY CAPITAL.LLC BUM MSUMMABYTABLE DEM4X PgMI BASIM ID TOTAL AflFA R CIO C100 2ryr i[ (min) IOMT[ (min)symon TO Oi WU B3 U100 IN .o Its EDT 0.63 063 a" 5.5 1 s sU ON O.o 0,13 .V A3 005 GAT Om aW 50 50 50 a10 0.1 a65 JA M ON O.R Ol3 ON 50 50 SA O.N 0.1 0.i3 A5 A4 007 ON am OR 50 50 SO a13 0 a50 I6 to 0.13 ON am IN 50 50 50 OA1 03 1.68 AT AT Om a83 041 IN 50 50 SO SIT 0 035 IH to OW 070 O.N 087 50 50 SA ON 01 036 at 91 am 09 035 031 53 53 50 ON 00 013 8E 8T ON aq Sly am 50 50 SA 0.N 0. 016 Cf 83 at5 0.0 ITS 50 50 50 OA 0. I31 N N am U25 035 031 50 50 5o am 0. 0,11 N 05 aI0 038 0Z 08 an SO 6.3 0.N 0.1 0m c c nN ed am Im 50 50 50 am 0 ON 0 a38 a81 ae1 Im 50 50 50 ON 1.5 391 a19 a@ D.@ 50 50 ON 0.5 IP I E aN DY ON .9 33 13.3 18A 066 0 t11 0 0 a19 Ob ON 031 95 93 93 0.11 0.1 069 Ml Cal Om OM 0.." am SO SO SA ON 0.0 0.19 ma N2 D.lt 0.35 93 OA3 al ® NORTH 6 va r.H Ixrml 1 LEGEND: 5a,„6 FRCPu3Eoo6aNa AET t� SCID 00101GUR on FROPOSSIDIVOLE PR0V4alY COMMUNITY — — OE90NParD Q ao..tmo. IMF 4=E Da.n+.wE R.siNa6EE Imc OANNAGE awN 11CUNSI — — PROPa5ED9N.LLE6EC[EW u mw9MNr.balow. Calloww9rw as City of Mort Collins. Colorado UTILITY PLAN APPROVAL wHflolca city ISWII O.,n CHECKED DY: er 101y LEAL CHECKED N. utiEty CHECKS),IM D— CHECKED HIT. 11 CHECKED BY: Oele Sheet DR1 Of 17 Sheets