HomeMy WebLinkAboutDrainage Reports - 10/27/2005Report _ WIrMu ate l �fz7l�s DRAINAGE AND EROSION CONTROL REPORT ' FOR Rigden Farm lath Filing - t Brooklyn Park Row Houses ' Prepared for: Hearne Properties, LLC 2426 Rock Creek Drive Fort Collins, Colorado 80528 Ph. 970.402.0312 Prepared by: Interwest Consulting Group 1218 W. Ash, Suite C t Windsor, Colorado 80550 Ph. 970.674.3300 Fax 970.674.3303 1 April 6, 2005 Revised June 15, 2005 t Revised September 14, 2005 Revised October 21, 2005 1 1 �S INTERWESTe C ON U LT I N G_ G.R?O;U.. P. 1 I INTERWES7 =: S 0 N S U L T I N G GROUP ' October 21, 2005 Mr. Basil Hamdan City of Fort Collins ' Stormwater Utility 700 Wood Street Fort Collins, CO 80521 ' RE: Drainage and Erosion Control Report— Rigden Farm I P Filing— Brooklyn Park Row Houses ' Dear Basil: We are pleased to submit to you for your final review and approval this Drainage and Erosion Control Report ' for Rigden Farm 11`" Filing — Brooklyn Park Row Houses. All computations within this report have been completed in compliance with the City of Fort Collins Storm Drainage Design Criteria and the approved Rigden Farm Filing Six Drainage and Erosion Control Report by JR Engineering dated July of 2001. ' We greatly appreciate your time and consideration in reviewing this submittal. Please call if you have any questions. I Sincerely, ' David Holloway Terry od gue, P.E. Project Engineer PPOO RE D/� O Sgoo V 30697 m �0�% �s`S�ONAL ENG\� 1 I I 1 I 11 TABLE OF CONTENTS PAGE 1. INTRODUCTION..................................................................................................................1 1.1 Project Description..........................................................................................................1 1.2 Existing Site Characteristics...........................................................................................1 1.3 Proposed Site Characteristics..........................................................................................1 1.4 Design Criteria................................................................................................................2 1.5 Master Drainage Basin.....................................................................................................3 2. LOCAL DEVELOPED DRAINAGE DESIGN...................................................................3 2.1 Method............................................................................................................................3 2.2 Hydrologic Analysis of the Proposed Drainage Conditions............................................3 3. EROSION CONTROL...........................................................................................................4 3.1 Erosion and Sediment Control Measures........................................................................4 3.2 Dust Abatement...............................................................................................................4 3.3 Tracking Mud on City Streets.........................................................................................5 3.4 Maintenance....................................................................................................................5 3.5 Permanent Stabilization..................................................................................................5 4. INDEMNIFICATION STATEMENT..................................................................................5 5. REFERENCES.......................................................................................................................7 Appendix A: Vicinity Map Appendix B: Hydrologic Calculations Appendix C: Erosion Control Calculations Appendix D: Calculations by Others 1. INTRODUCTION 1.1 Project Description Brooklyn Park Row Houses is a proposed multi -family condominium project located in Rigden Farm Subdivision, being the northwest quarter of Section 29, Township 7 North, Range 68 West, of the 61h Principal Meridian in the City of Fort Collins, Larimer County, Colorado. A vicinity map is provided in Appendix A. 1.2 Existing Site Characteristics The existing site is bordered on the south by Timberline Church, on the west by Iowa Drive, the east by the proposed Colony Development, and on the north by Custer Drive. 1.3 Proposed Site Characteristics This report defines the proposed drainage and erosion control plan for Rigden Farm 1 lth Filing - Brooklyn Park Row Houses. The plan includes all on -site and tributary off -site runoff and the design of all drainage facilities required with this development. The drainage report and drainage plan for this development is consistent with the design concepts and methodology of the "Final Drainage and Erosion Control Report for Rigden Farm Filing Six" dated July of 2001 as prepared by JR Engineering. The proposed development completely falls within original basins 108C and 108G as mentioned in the Rigden Farm Filing Six Report. The calculations done by JR Engineering for these two basins have been provided in Appendix D of this report. The 2-year developed flow for original Basin 108C is 2.43 cfs and 12.12 cfs for the 100-year developed flow. Original Basin 108G has a 2-year developed flow of 1.59 cfs and 6.92 cfs for the 100-year developed flow. Therefore, the combined flows from these two basins are approximately 4.70 cfs for the 2-year event and 19.04 cfs for the 100-year event per the calculations completed by JR Engineering. A Drainage Exhibit has been provided in the back pocket of this report depicting the different drainage basins associated with the proposed development. On this exhibit you will find a total of (8) eight on -site basins and (4) four off-site/undetained basins, which discharge directly onto Iowa and Custer Drive. These four basins directly correlate with original Basin Drainage and Erosion Control Report Rigden Farm I Vh Filing — Brooklyn Park Row Houses Page 1 October 21, 2005 G u 1 I 11 1 108C of both the Rigden Farm Filing One and Filing Six Drainage Reports. The eight on - site basins correlate with original Basin 108G of the same reports mentioned above. Proposed Basins OS 1, OS2, OS3 and OS4 (which is Basin 108C from the Rigden Filing One Report) release flows directly onto Iowa and Custer Drive ultimately discharging into an existing triple combination inlet, on the south side of Custer Drive at the eastern property line of this development. Calculations provided in the back of this report show that Basins OS 1, OS2, OS3 and OS4 have a combined 2-year developed flow of 1.60 cfs and a 100-year developed flow of 7.60 cfs. The combined flows for these proposed basins are less than that of original Basin 108C and decrease flows by approximately 0.8 cfs in the 2-year event and 4.52 cfs in the 100-year event. Proposed on -site Basins 1 through 8 will discharge directly into the existing 43"x68" Horizontal Elliptical Reinforced Concrete Pipe (HERCP) at various locations. This pipe flows south along the easterly property line and eventually discharges into an existing water quality pond designed by JR Engineering as part of Rigden Filing One Subdivision. Calculations provided in the back of this report show a combined 2-year developed flow of 3.40 cfs and a 100-year developed flow of approximately 14.0 cfs. This is an increase from the flows of original Basin 108G. It is an increase of approximately 1.8 cfs in the 2-year event and approximately 7.0 cfs in the 100-year event. In conclusion, the proposed development is adding approximately 1.0 cfs in the 2-year event and 2.48 cfs in the 100-year event to the existing 43"x68" storm sewer system along the eastern property line. The capacity of this existing 43"x68" storm pipe is approximately 136.40 cfs. The original calculated flow as designed and approved with the "Rigden Filing Six Drainage Report" by JR Engineering is approximately 93.5 cfs, which gives the existing pipe an excess capacity of 42.9 cfs. Due to the minimal increase in flows, as mentioned above, and the excess capacity in the existing storm sewer, it appears the existing storm pipe has the capacity to handle the additional flows of 1.0 cfs in the 2-year event and 2.50 cfs in the 100-year event. 1.4 Design Criteria This report was prepared to meet or exceed the submittal requirements established in the City of Fort Collins' "Storm Drainage Design Criteria and Construction Standards" (SDDCCS), dated May 1984 and revised in January 1997 and that of the "Final Drainage and Erosion ' III Drainage and Erosion Control Report Page 2 Rigden Farm 11" Filing — Brooklyn Park Row Houses October 21, 2005 1 iJ 1 I 1 Control Report for Rigden Farm Filing Six" by JR Engineering dated July of 2001, which supersedes the Filing One drainage report. Where applicable, the criteria established in the "Urban Storm Drainage Criteria Manual" (UDFCD) dated 1984, developed by the Denver Regional Council of Governments have been utilized. The rainfall criteria used was the April 1999 amended criteria. 1.5 Master Drainage Basin Rigden Farm 11`h Filing is located within the Foothills Master Drainage Basin. 2. LOCAL DEVELOPED DRAINAGE DESIGN 2.1 Method The Rational Method was used to determine the 2-year and 100-year flows for the drainage areas indicated in this drainage report. Drainage facilities were designed to convey the 100- year peak flows. The hydrologic calculations are found in Appendix B of this report. 2.2 Hydrologic Analysis of the Proposed Drainage Conditions The Rational Method was used to determine the 2-year and 100-year peak runoff values for each sub -basin. Runoff coefficients were assigned using Table 3-2 of the SDDCCS Manual. The Rational Method is given by: Q = CfCIA (1) where Q is the maximum rate of runoff in cfs, A is the total area of the basin in acres, Cf is the storm frequency adjustment factor, C is the runoff coefficient, and I is the rainfall intensity in inches per hour for a storm duration equal to the time of concentration. The frequency adjustment factor, Cf, is 1.0 for the initial 2-year storm and 1.25 for the major 100- year storm. The runoff coefficient is dependent on land use or surface characteristics. The rainfall intensity is selected from Rainfall Intensity Duration Curves for the City of Fort Collins (Figure 3.1 of SDDCCS). In order to utilize the Rainfall Intensity Duration Curves, the time of concentration is required. The following equation is used to determine the time of concentration Drainage and Erosion Control Report Rigden Farm 11i° Filing — Brooklyn Park Row Houses Page 3 October 21, 2005 I 1 1 1 I 1 1 tc = ti + tt (2) where to is the time of concentration in minutes, ti is the initial or overland flow time in minutes, and tt is the conveyance travel time in minutes. The initial or overland flow time is calculated with the SDDCCS Manual equation: ti = [1.87(1.1 - CCf)L0.5i/(S)0.33 (3) where L is the length of overland flow in feet (limited to a maximum of 500 feet), S is the average slope of the basin in percent, and C and Cf are as defined previously. All hydrologic calculations associated with the sub -basins shown on the attached drainage plan are included in Appendix B of this report. 3. EROSION CONTROL 3.1 Erosion and Sediment Control Measures Erosion and sedimentation will be controlled on -site by use of silt fences, inlet protection and straw bales as well as seeding and mulch or sod. The measures are designed to limit the overall sediment yield increase due to construction as required by the City of Fort Collins. During overlot and final grading the soil will be roughened and furrowed perpendicular to the prevailing winds. Erosion control effectiveness, rainfall performance calculations and a construction schedule are provided in Appendix C. 3.2 Dust Abatement During the performance of the work required by these specifications or any operations appurtenant thereto, whether on right-of-way provided by the City or elsewhere, the contractor shall furnish all labor, equipment, materials, and means required. The Contractor shall carry out proper efficient measures wherever necessary to reduce dust nuisance. Efficient measures shall be taken to prevent dust nuisance that has originated from the contractor's operations from damaging crops, orchards, cultivated fields, and dwellings, or causing nuisance to persons. The Contractor will be held liable for any damage resulting from dust originating from his operations under these specifications on right-of-way or elsewhere. Drainage and Erosion Control Report Rigden Farm I I" Filing - Brooklyn Park Row Houses Page 4 October 21, 2005 11 1 1 1 1 1 3.3 Tracking Mud on City Streets It is unlawful to track or cause to be tracked mud or other debris onto city streets or rights -of - way unless so approved by the Director of Engineering in writing. Wherever construction vehicles access routes or intersect paved public roads, provisions must be made to minimize the transport of sediment (mud) by runoff or vehicles tracking onto the paved surface. Stabilized construction entrances are required per the detail shown on the detail sheet, with base material consisting of 6-inch coarse aggregate. The contractor will be responsible for clearing mud tracked onto city streets on a daily basis. 3.4 Maintenance All temporary and permanent erosion and sediment control practices must be maintained and repaired as needed to assure continued performance of their intended function. Straw bale dikes or silt fences will require periodic replacement. Maintenance is the responsibility of the developer. 3.5 Permanent Stabilization A vegetative cover shall be established within one and one-half years on disturbed areas and soil stockpiles not otherwise permanently stabilized. Vegetation shall not be considered established until a ground cover is achieved which is demonstrated to be mature enough to control soil erosion to the satisfaction of the City Inspector and to survive severe weather conditions. 4. INDEMNIFICATION STATEMENT Garages that have finish floor elevations below an elevation of 4924.70 feet (minimum emergency overflow elevation) have potential for flooding in the event of a storm exceeding a 100-year storm event, back-to-back 100-year storm events, or if the flow into the two proposed 12-inch storm outlet pipes along the east side of this development become restricted. The proposed storm drainage system for this development has been designed for a 100-year storm event. An overall emergency drainage overflow path has been designed for the entire Rigden Farm Development which includes this site. The project is designed so that if and when the water reaches an elevation of 4924.70 feet the water will flow from this development. Drainage and Erosion Control Report Rigden Farm 11 �' Filing — Brooklyn Park Row Houses Page S October 21, 2005 Ll Hearne Properties LLC agrees, to the fullest extent permitted by law, to defend, indemnify and hold harmless Interwest Consulting Group Inc, and its sub -consultants from and against all claims, damages, liabilities or costs including reasonable attorneys' fees and defense costs, arising out of or in any way connected with the potential flooding of aforementioned garages. ' III Drainage and Erosion Control Report Page 6 Rigden Farm I Vh Filing— Brooklyn Park Row Houses October 21, 2005 4. REFERENCES 1. City of Fort Collins, "Storm .Drainage Design Criteria and Construction Standards" (SDDCCS), May 1984. 2. "Final Drainage and Erosion Control Report for Rigden Farm Filing One" by JR Engineering dated September 7, 1999. 3. "Final Drainage and Erosion Control Report for Rigden Farm Filing Six" by JR Engineering dated July of 2001. 4. Urban Drainage and Flood Control District, "Urban Storm Drainage Criteria Manual", Volumes 1 and 2, dated June 2001, and Volume 3, dated September 1992. 1 1 1 1 d APPENDIX A VICINITY MAP 0.. d �_ Z_ U .. } �; z I I 1 I i i I I I 1] 11 1 1 APPENDIX B HYDROLOGIC CALCULATIONS 1 1 1 1 1 i W K N � O C � U � W 0 N � O �- � Q N N Q r Q N Q r Q N 11 N O N_ U O O O O O O O o 0 0 0 Q o c 0 0 0 0 0 0 0 0 Oi 0 0 0 E vi vi ,ri vi vi ui vi vi r ui N vi u - e p 0 0 0 0 0 0 r r p t7 O i E y] H 1t) IN N It) N N m Yl N N o 0 o v1 p p p N 10 in a 0 0 0 0 0 0 U tq U o O o o O O G O O o O O 0 c o o 0 0 0 o 0 0 0 r 0 0 o 0 0 c r0 N M a N 0Q v1 a)r ro 0 0 0 0 N N Q N y 0 O � U � �. L, M � O Or P h � J y vl 0 O o � 0 � o Cyr Q- I I lJ I I RUNOFF COEFFICIENTS & % IMPERVIOUS LOCATION: Rigden Farm I lth Filing - Brooklyn Park Row Houses PROJECT NO: 1015-015-00 COMPUTATIONS BY: DRH DATE: 41612005 Recommended Runoff Coefficients from Table 3-3 of City of Fort Collins Design Criteria Recommended % Impervious from Urban Storm Drainage Criteria Manual Streets, parking lots (asphalt) Sidewalks (concrete) Roofs Lawns (flat <2%, sandy soil) Runoff % coefficient Impervious C 0.95 100 0.95 96 0.95 90 0.20 0 SUBBASIN DESIGNATION TOTAL AREA (ac.) TOTAL AREA (sq.fl) ROOF AREA (sq.ft) PAVED AREA (sq.ft) SIDEWALK AREA (sq.ft) LANDSCAPE AREA (sq.ft) RUNOFF COEFF. (C) % Impervious - 1 0.16 6,890 6,890 0 0 0 0.95 90 2 0.30 12,911 0 10,212 770 1,929 0.84 85 3 0.14 6,243 6,243 0 0 0 0.95 90 4 0.14 6,230 0 0 3,336 2,894 0.60 51 5 0.14 6,246 6,246 0 0 0 0.95 90 6 0.30 12,870 0 10,105 725 2,040 0.83 84 7 0.16 6,894 6,894 0 0 0 0.95 90 8 0.16 6,947 0 0 3,452 3,495 0.57 48 9S1— 1 0.79 34,274 0 21,630 2,522 10,122- 0.73 70 OS2 0.13 5,560 0 0 2,421 3,139 0.53 42 OS3 0.09 3,857 0 0 1,640 2,217 0.52 41 OS4 0.01 629 0 0 125 504 0.35 19 Equations - Calculated C coefficients & % Impervious are area weighted C=E(Ci Ai) /At Ci = runoff coefficient for specific area, Ai Ai = areas of surface with runoff coefficient of Ci n = number of different surfaces to consider At --'total area over which C is applicable; the sum of all Ai's F I } N Z O F N N ~ Z K W Z d 00 CC Q 0 o c LL = O o N W o F a T 0 0 O m W C f.% L O A C O 00 O CC�iaV II U } o] ti z o0 O F F <U m a o Oa040 ._1 a U 0 N N Y Q W w K 0000000r nocno y LL m m < VJ m 0 rn m O N O O � M a—im E� RI U y � V 2 m U 7 E N O m O) N a n r N t7 N U + � N N r N N m? ^ 0 0 0 C � N m n m N 0 0 0 O 0 G 0 O O L E t7 fV O N t7 V Ih LL J ? m V N V m« W N z z N > IC1,111 Q = U rn m m m m m m m m m�a a � L o 0 0 0 0 0 0 0 0 0 0 c a C� O 0 C C O G O 0 0 0 0 0 W O C O h 0 W) O h O N 0 O O O 7 O N O M O N O e m lw) w I Fmv�iv�ovQ'imn moon a �vv O O O n 0 0 0 (O m N t7 N E O O O O O O O O O O O O m N vi N u'i �i h N N N N O N O e N z W J O N O N O N t+J N r (h t7 N m _ m m rn m rn m N m r N N M J+ O G O G O O O G C O G C E � z_ F m 17 77 V�mc� n o0 N O O O O O o 0 0 O O O O U m N z y N th V Q N in? N m nm m 0000 m m z z N w a o N O 52 U) N J U U U) z 0 Q + m I I u n W U a N Z U U LL N � U O C _N m E .0 = -O O N j c� m E C LO N 11 + ` o E E E E U m c rr I 1 1 } CD 1 r T.. N M ~ Z cc W O Z 00 a U o LL QO N WW N ti C_ 3 rx 3 0 a O O 1 C 1 EO O °R o CG o � � Q V II U r m z o0 zz¢ € ' O U ::) i U O O V1 Y C Q i W C a 0 0 0 0 0 0 0 0 O O O a J IA N T N N� N r N to LO lc� r LL U( m Q It) Q m IU m Q N Q m C fh m 'ti o" Y N 00 J N N N m N N N N 10 N W � m U U D m m n m m m cn m A m N N (V CJ c'1 U � C N N N N m OEN O Cl 11`2 f7 N H IT LL J Q m Q m Q m Q O nl m m m w Z d N F .- N •- N N N N N N �Y Q> U m m m m m m m m m m m m m Q W C C 7 O 0 0 0 0 0 0 0 0 O O O O N O O N O m O Y1 niq O N a N O N O � O :V N N N N N O o� S N — w I M m a m m N o o o 0 0 H r Q In mm m J L N N N N N N N N N N W m r A y - J H r E 0 0 0 0 0 0 0 0 0 0 0 m N O N O Cl IA N N O O m o I(J _ O O O O m� N L.. N N N N t7 J O O O O r O O O A m (O m ZQ U o o 0 0 0 0 J U R' W N Q OMIT A N M N I[l O _ m m m In r N N N1 J O O O O 0 0 0 0 Q w U m E � 2 F Q Z N N Q m .-NmQ In tOAm OOOO cn to m co co z Z N m� Fa W 0 o a N C m - Z _ J U U LL � t O p U O m E n d = N N -E 7 o � � C q 'E C Lo a m I I a E E E C E w (U C w ll I 1 1 I 1 i 1 RATIONAL METHOD PEAK RUNOFF (City of Fort Collins, 2-Yr Storm) LOCATION: Rigden Farm l lth Filing - Brooklyn Park Row Houses PROJECT NO: 1015-015-00 COMPUTATIONS BY: DRH DATE: 4/6/2005 2 yr storm, Cf = 1.00 DIRECT RUNOFF ICARRY OVER ITOTAL REMARKS Design Point Tributary Sub -basin A (ac) C Cf tc (min) i (in/hr) Q (2) (cfs) from Design Point Q (2) (cfs) Q(2)tot (cfs) 1 0.16 0.95 5.0 2.85 0.43 0.43 0 2 0.30 0.84 5.0 2.85 0.71 0.71 0 3 0.14 0.95 5.0 2.85 0.39 0.39 0 4 0.14 0.60 5.0 2.85 0.25 0.25 0 5 0.14 0.95 5.0 2.85 0.39 0.39 - 0 6 0.30 0.83 5.0 2.85 0.70 - 0.70 0 7 0.16 0.95 5.0 2.85 0.43 0.43 0 8 0.16 0.57 5.7 ' 2.70 0.25 0.25 0 OS1 0.79 0.73 8.7 2.35 1.35 1.35 0 2S2 0.13 0.53 5.0 2.85 0.19 0.19 0 OS3 0.09 0.52 5.3 2.75 0.13 0.13 1 0 OS4 0.01 0.35 5.0 2.85 0.01 0.01 10 Q=CfCiA Q = peak discharge (cfs) C = runoff coefficient Cf = frequency adjustment factor i = rainfall intensity (in/hr) from City of Fort Collins OF curve (4/16/99) A = drainage area (acres) i = 24.221 / (10+ tcf"' 1 I 1 I 1 I i 1 RATIONAL METHOD PEAK RUNOFF (City of Fort Collins, 100-Yr Storm) LOCATION: Rigden Farm I Ith Filing - Brooklyn Park Row Houses PROJECT NO: 1015-015-00 COMPUTATIONS BY: DRH DATE: 4/6/2005 100 yr storm, Cf = 1.25 DIRECT RUNOFF ICARRY OVER ITOTAL REMARKS Des. Point Area Design. A (ac) C Cf tc (min) i (in/hr) Q (100) Ids) from Design Point Q (100) Ids) Q(100)tot (cfs) 1 0.16 1.00 5.0 9.95 1.57 1.6 2 0.30 1.00 5.0 9.95 2.95 2.9 3 0.14 1.00 5.0 9.95 1.43 1.4 4 0.14 0.75 5.0 9.95 1.07 1.1 5 0.14 1.00 5.0 9.95 1.43 1.4 6 0.30 1.00 5.0 9.95 2.94 2.9 7 0.16 1.00 5.0 9.95 1.57 1.6 8 0.16 0.72 5.0 9.95 1.14 1.1 OS1 0.79 0.91 7.9 8.47 6.07 6.1 OS2 0.13 0.66 5.0 9.95 0.84 i 0.8 OS3 0.09 0.65 5.0 9.95 1 0.6 OS4 0.01 0.44 5.0 9.95 0.06 0.1 Q=CiA Q = peak discharge (CIS) C = runoff coefficient i = rainfall intensity (in/hr) from City of Fort Collins IDF curve (4/16/99) A = drainage area (acres) I = 84.682 / (10+ tep.171 I I Worksheet for 5-foot Concrete Pan ;Project Description Flow Element: Irregular Section Friction Method: Manning Formula Solve For: Normal Depth (Input Data Channel Slope: 0.00500 ft/ft Discharge: 0.70 4— Zyr F—\ir—Wr ft3/S jfqpt�lons Current Roughness Weighted Meth( Improvedl-otters Open Channel Weighted Roughnes: Improvedl-otters Closed Channel Weighted Roughne Hortons F1 I I F I I C'. I I JR6iults, Roughness Coefficient: 0.013 Water Surface Elevation: 23.13 ft Elevation Range: 22.94 to 23.40 ft Flow Area: 0.42 ft' Wetted Perimeter: 4.48 ft Top Width: 4.47 ft Normal Depth: 0.19 ft Critical Depth: 0.18 ft Critical Slope: 0.00547 fUft Velocity: 1.67 ft/s Velocity Head: 0.04 ft Specific Energy: 0.23 ft Froude Number: 0.96 Flow Type: Subcritical (0+00, 23.40) (0+30, 23:40) 0013 0+00 23.40 7 0+ Il 3 23. 15 I i; Worksheet for 5-foot Concrete Pan Station _ Elevation. ' 0+15 22.94 i0+18 23.15 0+30 23.40 1 1 t i 1 r 1 1 I 1 1 1 i 1 1 1 1 2-year Event Cross Section for 5-foot Concrete Pan Project Description '_ _ __ Flow Element: Irregular Section Friction Method: Manning Formula Solve For: Normal Depth Section.Data Roughness Coefficient: 0.013 Channel Slope: 0.00500 ft/ft Normal Depth: 0.19 ft Elevation Range: 22.94 to 23.40 ft Discharge: 0.70 W/s 0.19 ft �-4A7 ft —{ I I C� I [i I 1 I U Worksheet for 5-foot Concrete Pan Project Description Flow Element: Irregular Section Friction Method: Manning Formula Solve For: Normal Depth tlnput Data 777 Channel Slope: 0.00500 ft/ft Discharge: 2.90 jCOyr EyEt-17— ft3/s Options Current Roughness Weighted Meth( ImprovedLotters Open Channel Weighted Roughnes: ImprovedLotters Closed Channel Weighted Roughne Hortons iResults Roughness Coefficient: 0:013 Water Surface Elevation: 23.26 ft Elevation Range: 22.94 to 23.40 ft Flow Area: 1.62 ft' Wetted Perimeter: 15.66 ft Top Width: 15.64 ft Normal Depth: 0.32 ft Critical Depth: 0.31 ft Critical Slope: 0.00526 ft/ft Velocity: 1.79 ft/s Velocity Head: 0.05 ft Specific Energy: 0.37 ft Froude Number: 0.98 Flaw Type: Subcritical (0+00, 23.40) (0+30„ 23.40) 0.013 0+00 23.40 :0+13 - 23.15 I I I I Worksheet for 5-foot Concrete Pan 'Station - Elevation 0+15 22.94 +18, _- - `23.15� 0+30 - 23.40 11 I I I .I ICI LJ I I I I I I 100-year Event 1 Cross Section for 5-foot Concrete Pan iProject Description .` ' Flow Element: Irregular Section Friction Method: Manning Formula 1 Solve For: Normal Depth Section Data Roughness Coefficient: 0.013 I Channel Slope: 0.00500 ft/ft Normal Depth: 0.32 ft Elevation Range: 22.94 to 23.40 ft Discharge: 2.90 ft'/S L 1 I ' 0.32 ft I i� 1 v:1 N, K1 C� Worksheet for Cross Section A -A Flow Element: Friction Method: Solve For: Triangular Channel Manning Formula Normal Depth Roughness Coefficient: 0.030 Channel Slope: 0.01000 ft/ft Left Side Slope: 4.00 ft/ft (H:V) Right Side Slope: 4.00 ft/ft (H:V) Discharge: 1.10 ft 3/s Results ':F Y r fry .- Normal Depth 0.41 ft Flow Area: 0.66 ft' Wetted Perimeter: 3.34 ft Top Width: 3.24 ft Critical Depth: 0.34 ft Critical Slope: 0.02459 ft/ft Velocity: 1.67 ft/s Velocity Head: 0.04 ft Specific Energy: 0.45 ft Froude Number: 0.66 Flow Type: Subcritical Downstream Depth: 0.00 ft Length: 0.00 ft Number Of Steps: 0 tGUF Output Data Upstream Depth: 0.00 ft Profile Description: N/A Profile Headloss: 0.00 ft Downstream Velocity: 0.00 ft/s Upstream Velocity: 0.00 ft/s Normal Depth: 0.41 ft Critical Depth: 0.34 ft Channel Slope: 0.01000 ft/ft Critical Slope: 0.02459 ft/ft Cross Section A -A ' Cross Section for Triangular Channel - 1 Project Descnptiori - _ '- ,.a,.. a, ' Flow Element: Triangular Channel Friction Method: Manning Formula ' Solve For: Normal Depth Data > * 1a rsaF r "4 ISechon Roughness Coefficient: 0.030 Channel Slope: 0.01000 ft/ft Normal Depth: 0.41 ft Left Side Slope: 4.00 ft/ft (H:V) Right Side Slope: 4.00 ft/ft (H:V) Discharge: 1.10 ft3/s [1 I7 T 0.41 ft � � 1 1 [1 I I [1' I I I I I I ' Proposed S1 I I I 11 I I I I Scenario: Base Ex. Inlet 8c Title: Brooklyn Park Row Houses Project Engineer: Interwest Consulting Group d:\...\drainage\design\south storm.stm Interwest Consulting Group StormCAD v5.5 [5.5005] 06/14/05 02:33:39 PM ©Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06706 USA +1-203-755-1666 Page 1 of 1 I gg"N NJ Mai 7 --------------------------------------- 02 0. 1 a i a Title: Brooklyn Park Row Houses d:\...\drainage\design\south storm.stm 06/14/05 02:36:07 PM Profile Scenario: Base Profile: Profile - 1 Scenario: Base ow S=(N 7100 Interwest Consulting Group OHaestad Methods, Inc. 37 Brookside Road Waterbury, CT06708 USA +1-203-755-1666 &-a I 4.MOD 4,92500 4=00 Beau(fo 4,91500 1" Project Engineer: Interwest Consulting Group StormCAD v5.5 [5.5005] Page 1 of 1 APPENDIX C EROSION CONTROL CALCULATIONS [1 I I �I RAINFALL PERFORMANCE) STANDARD EVALUATION PROJECT: Rigden Farm llth Filing - Brooklyn Park Row Houses STANDARD FORM A COMPLETED BY: DRH DATE: 21-Ocn05 DEVELOPED ERODIBILITY Asb Lsb Ssb Ai' Li Ai • Si Lb Sb PS SUBBASIN(s) ZONE (AC) (FT) (%) (FT) 1 MODERATE . 0.16 265 0.5 41.9 0.1 2 MODERATE 0.30 281 3.0 93.3 0.9 3 MODERATE 0.14 243 0.5 34.8 0.1 4 MODERATE 0.14 95 2.8 13.6 0.4 5 MODERATE 0.14 243 0.5 34.8 0.1 6 MODERATE 030 281 3.0 83.0 0.9 7 MODERATE 0.16 263 0.5 41.6 0.1 8 MODERATE 0.16 280 2.4 44.7 0.4 OS1 MODERATE 0.79 615 1.6 483.9 1.2 OS2 MODERATE 0.13 35 25.0 4.5 3.2 OS3 MODERATE 0.09 70 5.0 6.2 0.4 OS4 MODERATE 0.01 20 25.0 0.3 0.4 Total 2.51 1 1 872.61 8.09 347 3.2 82.1 % Ash = Sub -basin area Lsb = Sub -basin flow path length Ssb = Sub -basin slope ' Lb = Average flow path length = sum(Ai Li)/sum(Ai) Sb = Average slope = sum(Ai Si)/Sum (Ai) PS is taken from Table 8-a (Table 5.1, Erosion Control Reference Manual) by interpolation. ' An Erosion Control Plan will be developed to contain PS°/o of the rainfall sedimentation that would normally flow off a bare ground site during a 10-year, or less, precipitation event. I L EFFECTIVENESS CALCULATIONS PROJECT: Rigden Farm I Ith Filing - Brooklyn Park Row Houses STANDARD FORM B COMPLETED BY: DRH DATE: 06-Apr-05 EROSION CONTROL C-FACTOR P-FACTOR METHOD VALUE VALUE COMMENT BARE SOIL 1.00 1.00 SMOOTH CONDITION ROUGHENED GROUND 1.00 0.90 ROADS/WALKS 0.01 1.00 GRAVEL FILTERS 1.00 0.80 PLACED AT INLETS SILT FENCE 1.00 0.50 SEDIMENT TRAP 1.00 0.50 STRAW MULCH (S = 1-5%) 0.06 1.00 FROM TABLE 8B STRAW BARRIERS 1.00 0.80 EFF = (1-C*P)* 100 MAJOR SUB BASIN AREA EROSION CONTROL METHODS BASIN BASIN (Ac) 1 0.16 ROADS/WALKS 0.00 Ac. ROUGHENED GR. 0.16 Ac. STRAW/MULCH 0.00 Ac. OUTLET RIPRAP NET C-FACTOR 1.00 NET P-FACTOR 0.72 EFF = (1-C*P)*100 = 28.0% 2 0.30 ROADS/WALKS 0.25 Ac. ROUGHENED GR. 0.00 Ac. STRAWIMULCH 0.04 Ac. GRAVEL FILTER @ FES NET C-FACTOR 0.02 NET P-FACTOR 0.80 EFF = (1-C*P)*100 = 98.6% 3 0.14 ROADS/WALKS 0.00 Ac. ROUGHENED GR. 0.14 Ac. STRAW/MULCH 0.00 Ac. DISCHARGES INTO CLOSED SYSTEM NET C-FACTOR 1.00 NET P-FACTOR 0.72 EFF = (1-C*P)*100 = 28.0% 4 0.14 ROADS/WALKS 0.08 Ac. ROUGHENED GR. 0.00 Ac. STRAW/MULCH 0.07 Ac. INLET FILTER STRAW BALE NET C-FACTOR 0.03 NET P-FACTOR 0.80 EFF = (I-C*P)*100 = 97.3% I 1 I 1 1 PROJECT: Rigden Farm I Ith Filing- Brooklyn Park Row Houses STANDARD FORM B COMPLETED BY: DRH DATE: 06-Apr-05 EROSION CONTROL C-FACTOR P-FACTOR METHOD VALUE VALUE COMMENT BARE SOIL 1.00 1.00 SMOOTH CONDITION ROUGHENED GROUND 1.00 0.90 ROADS/WALKS 0.01 1.00 GRAVEL FILTERS 1.00 0.80 PLACED AT INLETS SILT FENCE 1.00 0.50 SEDIMENT TRAP 1.00 0.50 STRAW MULCH (S = 1-5%) 0.06 1.00 FROM TABLE 8B STRAW BARRIERS 1.00 0.80 EFF = (I-C*P)* 100 MAJOR SUB BASIN AREA EROSION CONTROL METHODS BASIN BASIN (Ac) 5 0.14 ROADS/WALKS 0.00 Ac. ROUGHENED GR. 0.14 Ac. STRAW/MULCH 0.00 Ac. DISCHARGES INTO CLOSED SYSTEM NET C-FACTOR 1.00 NET P-FACTOR 0.72 EFF = (I-C*P)*100 = 28 0% 6 0.30 ROADS/WALKS 0.25 Ac. ROUGHENED GR. 0.00 Ac. STRAW/MULCH 0.05 Ac. GRAVEL FILTER @ FES NET C-FACTOR 0.02 NET P-FACTOR 0.40 EFF = (1-C*P)*100 = 99.3% 7 0.16 ROADS/WALKS 0.00 Ac. ROUGHENED GR. 0.16 Ac. STRAW/MULCH 0.00 Ac. DISCHARGES INTO CLOSED SYSTEM NET C-FACTOR 1.00 NET P-FACTOR 0.72 EFF = (I-C*P)* 100 = 28.0% 8 0.16 ROADS/WALKS 0.08 Ac. ROUGHENED GR. 0.00 Ac. STRAW/MULCH 0.08 Ac. INLET FILTER STRAW BALE, SILT FENCE NET C-FACTOR 0.04 NET P-FACTOR 0.80 EFF = (1-C*P)*100 = 97.2% OS1 0.79 ROADS/WALKS 0.55 Ac. ROUGHENED GR. 0.00 Ac. STRAW/MULCH 0.23 Ac. SILT FENCE NET C-FACTOR 0.02 NET P-FACTOR 0.80 EFF = (I-C*P)* 100 = 98.0% 1 PROJECT: Rigden Farm l Ith Filing -Brooklyn Park Row Houses STANDARD FORM B COMPLETED BY: DRH DATE: 06-Apr-05 EROSION CONTROL C-FACTOR P-FACTOR METHOD VALUE ' VALUE COMMENT BARE SOIL 1.00 1.00 SMOOTH CONDITION ROUGHENED GROUND 1.00 0.90 ROADS/WALKS 0.01 1.00 GRAVEL FILTERS 1.00 0.80 PLACED AT INLETS SILT FENCE 1.00 0.50 SEDIMENT TRAP 1.00 0.50 STRAW MULCH (S = 1-5%) 0.06 1.00 FROM TABLE 8B STRAW BARRIERS 1.00 0.80 EFF = (I-C*P)* 100 MAJOR SUB BASIN AREA EROSION CONTROL METHODS BASIN BASIN (Ac) OS2 0.13 ROADS/WALKS 0.06 Ac. ROUGHENED GR. 0.00 Ac. STRAW/MULCH 0.07 Ac. SILT FENCE NET C-FACTOR 0.04 NET P-FACTOR 0.80 EFF = (I-C*P)* 100 = 96.9% OS3 0.09 ROADS/WALKS 0.04 Ac. ROUGHENED GR. 0.00 Ac. STRAW/MULCH 0.05 Ac. SILT FENCE NET C-FACTOR 0.04 NET P-FACTOR 0.80 EFF = (1-C*P)*100 = 96.9% OS4 0.01 ROADS/WALKS 0.00 Ac. ROUGHENED GR. 0.00 Ac. STRAW/MULCH 0.01 Ac. SILT FENCE NET C-FACTOR 0.05 NET P-FACTOR 0.80 EFF = (I-C*P)*100 = 96.0% TOTAL AREA = 2.51 ac TOTAL EFF = 82.3% ( E (basin area * eff) / total area REQUIRED PS = 82.1% Since 82.3% > 82.1 %, the proposed plan is o.k. PAGE 23 1 I ' 0 1 cc,ccc I 1 O I c c IC! 1n 1 LO I C C co C W I 1 1 1 I O TC. , +p, CJnCCCCCC I I , I 1 G I cc ccoc IC% W W cc u': ICl 03 co I 1 c 1 tl C C C C W tl I 1 ' qCT G. C. .G�0. .0. G. . . . I I , I I G l c c c c c c c c c c c c Ir I.n 111 , W co C Ct.7CC ccCCC co co I 1 I I rCCticr. rncrnG+a,a+rn CT 01 cr. G+rn CNO+C+ I ! I 1 1 p I c c c c c c c c c c c c c c v c c c c c I 1 1 ! C I CMCIn Ip Olp %pW WCW W • I , 1 O I co W co co tl coC CC cc C WCtlW WC~ CCW W I 1 r-1 I cc co C I 1 O I C N C 17 c I n t n 1--I a O 1 G t D W tl g T T T r T T r r r r co W CO 1 C 1 I C 1 1 W C t t W C c C O Q Q C9 C O C O c 0 C 7 c O C o c O Q Q C C [7 cc CCC I C 1 1 O t O 1 100 . . . . .to In lC. t0 `U IG 101D t.tr. t.t0 t0rrrrT . 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T T T T r r W W CO W CO W W CO W W tl tl W W W ; 1 1 CDt0MOC , N C7 M C C to In Lo In tD%C ID tO Tr tD lO Io 1 1 1 . .O . 1 ..I I C'tGTTTr CO q wW q co tl CO Go co CO co Go co co co co co co W I 1 , T T T n T r T r T T T T T T T T T T T T T T r T 1 , r! O1 IO 1 1 W 1 OIO C1.0rgtlrTT%O IO aO InCC1'nMNNCJI tOC 1 1 , t CD I O N N N N N N N N N N N N N N N N N N N .-1 ^ '"1 rl CD CD 1 r r r T T T T r r r T T T l` r r T r r T r I CD C_ O O co O C 0 0 0 0 0 C O CD O C 0 0 0 0 0 0 0 0 0 1 t CJ Zt+- / �NC•7c �aO �tl CTOONOv1['J aO�C^.�CTGOO 7C tnO I 1 Cl)Cl) 1� W �..• 1 .-1 e--1 r-1 r• r'1 r'1 •+ ^� r'1 r1 cmN 1 J 1 TABLE 5.1 Rigden Farm 11th Filing - Brooklyn Park Row Houses Erosion Control Cost Estimate JOB NO. 1015-015-00 -. • nT I I n COMPLETED BY: DRH ITEM vDESCRIPTION UNITS I UNIT COST QUANTITY TOTAL COST 1 TEMPORARY SEED & MULCH ACRE $ 775.00 1.0 $ 775.00 2 SILT FENCE LF $ 3.00 741 $ 2,223.00 3 INLET PROTECTION EACH $ 250.00 5 $ 1,250.00 4 GRAVEL CONSTRUCTIOTT ENTRANCE EACH $ 500.00 2 $ 1,000.00 COST $ 5,248.00 l /1111 111 TIIT A T OTT V A D V A vy ITEM DESCRIPTION UNITS UNIT COST QUANTITY TOTAL COST 1 RESEED/MULCH ACRE $ 775.00 1 1.0 $ 775.00 COST $ 775.00 SECURITY DEPOSIT $ 5,248.00 REQUIRED EROSION CONTROL SECURITY DEPOSIT WITH FACTOR OF 150% $ 7,872.00 I CONSTRUCTION SEQUENCE Project: Riqden Farm 11 th Filing - Brooklyn Park Row Houses Date: October 21, 2005 ..a --.: ------- ---- —01 �nH ... h.n PRAP'c .All hp inqtn1lprI1rpnnnvp.r1 in relation to the construction Dhase CONSTRUCTION PHASE (2005-2006) JAN FEB MAR I APR MAY JUN JUL AUG SEPT I OCT NOV DEC 1 Grading (include Offsite) mr, Overlot DetentionfWQ Ponds Swales, Drainageways, Streams Ditches Pipeline Installation (include Offsite) Water APATTIM Sanitary Sewer A�Wpftloo Stormwater Iwo Concrete Installation (include Offsite) olwai Area Inlets Curb Inlets Pond Outlet Structures Curb and Gutter Box Culverts, Bridges Street Installation (Include Offsite) Gradiing/Base Pavemernt Miscellaneous (include Offsite) Drop Structures Other (List) BEST MANAGEMENT PRACTICES Structural Silt Fence Barriers *491SW P low Contour Furrows (Ripping/Disking) Sediment Trap/Filter IW-,Iqk SIM Vehicle Tracking Pads Flow Barriers (Bales, Wattles, Etc) WIN Inlet Filter A Wxl`� Sand Bags Bare Soil Preparation Terracing Stream Flow Diversion Rip Rap Other (List) Vegetative Temporary Seed Planting Mulching/Sealant Permanent Seed Planting Sod Installation Nettings/Blankets/Mats Other (List) APPENDIX D CALCULATIONS BY OTHERS 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 JR Engineering, Ud. 2620 E. Prospect RC., Ste. 190, Fort Collins, CO 80525 RATIONAL METHOD PEAK RUNOFF Minor Storm for Residential Areas (2-YEAR) LOCATION: RIGDEN FARM FILING ONE, P.D.P. PROTECT NO: 9164.03 COMPUTATIONS BY: A. REED SUBMITTED BY: JR ENGINEERING, LTD. DATE: 8/11/99 2 yr storm, CI = 1.00 DIRECT RUNOFF ICARRY OVER ITOTAL REMARKS Design Tributary A C CI tc I O (2) from O (2) O(2)tot Sub -basin Design Point (ac) (mn) (in/hr) I Ids) Pant (cis) ids) 1 101 10.52 0.77 14.0 1.92 15.69 5.69 1a late 3.14 0.87 8.4 2-38 6.51 .51 6.51 lb 101 b 1.37 0.93 5.0. 285 3.63 3 3 63 1c 101C 324 0.69 8.1 241 5.39 5.39 1d 101d 3.40 0.91 7.0 254 7.B4 7.84 2 102 4.16 0.77 10.7 2-16 6.96 6.9fi 2a 102a 3.95 0.73 13.1 1.98 5.70 5.70 2b 102b 257 0.71 9.7 225 4.09 4.09 3 103 271 0.75 8.5 236 4.81 4.81 4 104 1.35 0.76 5.0 285 291 2-91 42 104a 1.37 0.79 5.4 2.74 2.99 299 105 4.43 0.45 11.5 210 4.22 422 5 105+104+104a+ 18.67 0.67 19.2 1.65 20.75 20.75 103+102b+111+112 6 106 247 0.10 10.4 219 0.54 0.54 7 107 5.33 0.91 7.5 247 12.03 1203 7a 107a 264 0.87 8.6 2-36 5.43 7b 107b 1.81 0.87 7.2 2-52 3.99 3.99 .9 7c 107c 2.16 0.79 9.1 2.31 3.92 PZ.59 3.92 7d 107d 3.42 0.75 14.8 1.88 4.4 4.81 Ire 107e 216 0.75 11.0 214 3.44 3.44 8 108 1.01 0.95 9.2 2-30 219 219 Ba 108a a.88 0.79 6.7 257 1.79 Bal 4.38 C/O to OP Bbt 108al 0.71 0.73 8.9 2-33 1.21 Sd 1.38 259 C/O to DP 8a Sb 108b 0.68 0.88 5.8 2.89 1.61 Bbl 1.53 3.15 C/O to DP. 8c 108bl 0.62 0.76 5 0 285 1.34 Ba 0.19 1.53 C/O to DP Bb Bc -..1:30>-- 0.79;..., 87.:_y �,_;.235 •: :243' 9 8b 0.05 248 8d 108d 0.51 0.95 5.0 285 1.38 1.38 C/O to DP Bal Be 108e- _ 2.24 - 0.65 14.0 1.92 2-80 2-80 at 108f 1.44 0.67 127 202 1.95 1.95 gr'josg�' :••_•33: -1.18-- -0.68^: -.•123 _. 204 -159:.8 1.59 lose-108g 4_86 0.88 17.8 1.71 5.49 5.49 109 5,46 0.65 14.0 1.92 6.83 - 6.83 9 107d+107e+108+109 12D4 0.72 18.3 1.69 14.63 14.63 109a 0.65 14.5 1.89 15.47 15.47 9a 107a-107c+lase-108g+109a 0.69 21.2 1.56 30.89 30.89 10a 110a 0.95 5.0 285 0.68 9.68 lob 110b 0.95 5.0 285 0.68 0.68 11 111 N2.69 0.72 13.8 1.94 7.81 7.81 12 112 0.95 5.0 2.85 1.70 1.70 13 113 0.84 6.1 2.64 5.95 5.95 114 0.77 8.7 2.35 5.04 5.04 C/O to Basin 115 14 lqa 114a 0.65 10.7 2.18 2.15 2.15 pdpFLC)W.XLS 1 1 i 1 1 1 1 1 1 1 1 1 1 1 1 JR Englneering. Ltd. 2620 E. Prospect Rd., Ste. 190. Fort Collins, CO 80525 RATIONAL METHOD PEAK RUNOFF (100-YEAR) LOCATION: RIGDEN FARM FILING ONE, P.D.P. PROJECT NO: 9164.03 COMPUTATIONS BY: A. REED SUBMTMD BY: 1R ENGINEERING, LTD. DATE: 5/30/99 100 yr storm, Cf = 1.25 DIRECT RUNOFF ICARRYOVER ITOTAL REMARKS - Des. Point Area - Design. A (ac) C Cf tc (rnin) i (in/hr) O (100) (CIS) from Design Pant O (100) (CIS) O(1 OO)tot (CIS) 1 101 10.52 0.97 12.3 - 7.12 -72-56 - 72.6 - la Iola - - 3.14 1.00 6.5 9.06 28.43 -28.4 lb 10lb 1.37 1.00 5.0 9.95 13.63 13.6 - tc 101c 3.24 0.86 5.0 9.95 27.79 27.8 ld 101d 3.40 1.00 5.8 9.37 31.88 31.9 102 4.16 0.97 7.1 8.78 35.32 35.3 22 102a 3.95 0.91 10.6 7.59 27.25 272 2b 3 102b 103 2.57 2.71 0.86 0.94 7.3 6.1 8.70 921 19.74 23.43 2b 5.16 19.7 28.6 C/O to OP 3 ern. overflow to DP 4 4 104 1.35 0.95 5.0 9.95 12-72 4a 2.70 15.4 44a 1042 1.37 0.99 5.4 9.58 13.04 13.0 C/O to DP 4 105 - 4.43 0.57 11.5 7.33 18.40 18.4 5 105+104+104a+ 103+102b+111+112 18.67 0.84 192 5.75 90.48 . 90.5 Spill 6 106 2.47 0.13 10.4 7.63 236 24 7 7a 107 107a 5.33 2.64 1.00 1.00 5.9 7.5 9.34 8.62 49.77 22-76 49.8 22-8 CIO to OP 7b 7b 107b 1.81 1.00 5.8 9.37 16.99 7a 7.42 24.4 C/O to DP 7c 7c 107c 2.16 T99 7.1 8.78 18.67 7b 8.21 26.9 C/O to DP 7d 7d 107d 3.42 0.94 10.3 7.69 24.61 7c 9.53 34.1 CIO to DP 7e 7e 107e 2.16 0.93 8.0 8.46 17.01 7d 12.77 29.8 C/O to DP B 8 108 1.01 1.00 9.2 8.02 8.06 7e+8c 11.02 19.1 Be 108a 108al . 0.88 0.71 0.98 0.91 5.0 6.0 9.95 9.30 8.66 6.05 921 1 Bd 11.10 5.07 19.8 11.1 C/O to DP 8bl CJO to DP Be fib 108b 0.68 1.00 5.0 9.95 6.76 8bl 11.54 18.3 C/O to DP Sc 108bl 0.62 0.95 5.0 9A5__. -..5.87 9a 5.67 11.5 C/O to DP 8b Bo 8d _ --- hloscgw.�� 108d ', 1 30 -- r. 0.51- 0.99 1.00 '-5.8 5.0 ' 9.37 _ 9.95 _ 1212- 5.07 f 8b 4.98 17.1 5.1 C/O to DP 8 C/O to OF Bat Be 108e 224 0.81 14.0 6.71 - 12.23 12-2 at loaf _ 1.44- 0.94 .127 7.03 8.48 Be 12.23 20.7 ---�108e-108g =.=0.83- _' %123 _ ... 7.11 �.,, - 6.92'a^r 6.9 4.86 0.82 1-78 5.98 23.92 23-9 109 5.46 0.81 13.9 6.73 29.87 29.9 9 107d+107e+108+109 12.04 0.90 18.3 5.88 63.80 63.8 109a 12.58 0.81 14.5 6.60 67.46 67.5 9a 107a-107c+108a-108g+109a 28.76 0.86 27.2 5.44 134.66 134.7 loa 110a 025 1.00 5.0 9.95 250 2.5 10b 110b 0.25 1.00 5.0 9.95 250 25 11 12 111 112 5.61 0.63 0.90 1.00 8.6 5.0 8.24 9.95 41.45 6.26 41.5 6.3VC/OP 16b13 14 113 114 269 279 1.00 0.96 5.0 5.7 9.95 9.40 26.81 25.19 14C 4.01 26-8 29.2P 15 iqa 114a 1.53 0.81 It.7 8.21 10.20 10.2 pdpFLOW.XLS C vo f LL OD Q N cM cM r- i 7. r 5 U u U > w m� d M d w w w w w w n o w n o N o C J Q U� � w- N N N N N N N O) = O) O W O) Ol O) W 0 v a v v v v v v c M d d o d d o 0 0 O M 0) O M Ol O O N Q 0W OO Ni m W m'm m m a Ni d d d d d d d d d co n M w o o CO iv w r d N 0) O N O) n d N ❑ > � O m Ol T O) to O 0) O) C Y d V V V V d V V J n d N N w d w O � C) � m ONE ONi � � ONi ONE O1 m = d d d d d d d d d O M O O O M 01 N O a> of (o of v of (o vi m v N N N N N N N N N � 0 V v<< O O d V 'R � > = N N N N N N O) 01 tr O O O O) O O) d d d d, O w w N N M O O) d N W O w O d d O) w CIL m� w w w N O) d w w m D' Cl) o0i �n o a n n N (O r t7 m m m r r Q N m N O O m awD N O Of O) O O O) O) O O 0 0 0 0 U) 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 C �p m m m -m Cm m U U U U U UCU n w w (D OMLU V77 NLdU MOLU OW CD (D m O m �FNMdMdwLNUC-0 Q 0 F-c o mMMMdOLdUCm aNwldwdLNUCUC lNOLdU 'fH0O°td'wLOW U(MwwMMULNUCC !i 0 a nPQ-j 3 Cl n Q'QIIQ; U 0N 0.eJLC�NUmm OOOU 0 pibF ;¢ `=I ¢ m U (D ¢ m, UI= n aaaaalal'aiF�; n n w w m w� m �Un 1� N \±, +.n Olcl - -_ - - - - All- f i' 1C • - A I 411 la li 1 I 1 I 01er 3.24 1 lOJ• DRAINAGE EAYVENi J I 3.33« -�I � 2T - 4✓ II II 010• I. 1 I ! 3.14 as I I I I I Is Olb* is IF / ;I�+ II •\ 070 1 I I O + TO LL CCMBINATQI �11E I. .. _ryvliEAsguI.. I A IP mom- t 1 � I �I 1SE1 (YCgrIEB 1 TRACT AONE OBe• ' / 221 «/. o v ,1 /(RTjICkBE Mtl - D ___/ / IF 1 m1nE careM�nox s �� 7dalla�� m ©1. � 01111 1� E t I v: m v 100 100 200 SCALE: 1' - too' TRACT C I CWBLE TWE 0 MFA HAFT (YCOINED) R - I' I' - I I � 1090 TRACT D 17.50 I II �I + I "iEV#R}tM" WATER WAIIEYON I -' 1511N NR(BEF OF AN SHEET II / �. �. I_1 / I yam/ `,\,� IF* , i Li It I / N.., 1 I KE?'MAP \ 102r nil I \) 1 � -'- E EN rsE MPC; Oro o7r�� ctill II DO Ry D DESIGN PDIHT N y" 1 1030 IV 1�1 BASIN CRIiF in-SU3� zn « �APEA cpEjP� I W. Af,NEs Is a r T1Tr F � BASIN BOUNDARY � 16' iliE R MLE \ W - __ __ E%ISiING, DEFT _ o If PROPOSED INLET AND I' RE a 24 R FLARED ENO SECTION Ell d � �__ •.• _._ _ • SIDEWALK CULVERT q y s _ ET I f { ______ ➢PERMLEi-CC i ! _ se �� O EROSION BALES {y HI y 1� A - -v,. 1 IS TYPE RII 109 % 1[ _ Y r r IL—B TWEL_ MATCHLWE - SEE SHEET 27 III PROPOSED INLET LOCATION q W q "'UUUId , — E%ISnNC 5' CONTOUR 'T / wow ---- EXISTING I' CONTOUR " PROPOSED 5' CONTOUR TRACT F /� PROPOSED 1' CONTOUR `• I •• ® SET FENCE V V INLET PROTECTION. ♦`/ O CONSTRUCTION ENTRANCE ST SEDIMENT TRAP APPEAR APPROVED 10p YR. FLOOD - u PIAIN LIMIT$ (2.89- RAINFALL) AI' • BASIN DELINEATIONS ARE BASED ON FUTURE \ DEVELOPMENT AND ,.MATCH CONTOURS BOUNDARIES MAY NOl' SHOWN. 3 RPRAP (BNREO � RBO REYEO TERSVLLm OUTED LET C 1F tt4E DETAIL IN L +W'INPRAP W OURI (BURIED" AND II . AND asHEDEL) MI 27 / PREPMEO UNDER 1XF pRFCi 9lPFAN9CN Cf P J TER (GR1Y WT£T / UCFURE (SHE DEAL ON SHEET )/ Z Z J O Lf C) J Z Z J A ' goy UI i'� 7� L �:vR B TYPE BUFFER Z'I. EC fVT NO PEgEOEOM City: of Fort Collins, Colorado.' UI li i` Elf 'Z -=zr_ AND Y MPRAP UTILIN P-n < Q a .(BURIED AND RFYED[OP r r C ��'�9L Lill. w APPIR). Ad p y EngNee, -:. Oa1a Ur w CHECKED II AIA C) W Of %aL s , 0 Q CHECKED BY: Al /O 9Y Y- LC Z W WINE f 'k CHECKED BY: C //0-'F 7Y _ C? �or�a R R.v,,tNw Dolt - CHECKED BY: —_ _ SHtt: 2� OF FIND, Engineer IolyJJ CHECKED BI to all RP - Dd � 41 I • I I ---------------- -------------- II \ II \ Ex aB,W.4rr MfeT I I \ BIM EYEv M-4m].l 1 BEM nEv n4 _ _ _ i� lee II Lee II i I �ng26� EX MAWAX MET u fws49%E E . ON REV NC0122 �l 11 /ll 111 111 'I I I I \ 1 1 I 1 I I �I I 1 II I ]ff- t,92 a W ff- -�xm 4a9) p ao (/yt taro x 5.0% ].OF y, 2.6S 3� NNffi 2500 2yW k 24b5 6 0 0 -490JIM Be cf- aww N-49IRStl G!-N/R.W Gp., i 755 © F.Y. w fIi Q:"w PF. 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