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HomeMy WebLinkAboutDrainage Reports - 07/01/2002PRO -- Or'�-F Final Ap port JUN 2 o 2002 FORTIM 02 DRAINAGE AND EROSION CONTROL REPORT WERNER ELEMENTARY SCHOOL SITE REMODEL June 20, 2002 J J R ENGINEERING I 1 DRAINAGE AND EROSION CONTROL REPORT WERNER ELEMENTARY SCHOOL SITE REMODEL June 20, 2002 Prepared by JR ENGINEERING 2620 E. Prospect Rd., Suite 190 Fort Collins, Colorado 80525 (970)491-9888 Prepared for Poudre School District Previous revision date: March 22, 2002 April 26, 2002 Job Number 39342.00 C 1 tJune 20, 2002 J•R ENGINEERING ' Mr. Basil Hamdan ASubsidiary efWestrian City of Fort Collins Stormwater Utility t 700 Wood Street Fort Collins, CO 80521 RE: Drainage and Erosion Control Report for Werner Elementary School Site Remodel ' Dear Basil, We are pleased to submit to you, for your review and approval, this Drainage and Erosion Control tStudy for the Werner Elementary School Site Remodel. All computations within this report have been completed in compliance with the City of Fort Collins Storm Drainage Design Criteria. 1 1 We appreciate your time and consideration in reviewing this submittal. Please call if you have any questions. Sincerely, Mark A. West, E.I. Design Engineer John Proje ' 2620 Fast Prospect Road, Suite 190, Fort Coffins, CO 80525 970-491-9888 • Fax: 970-491-9984 • w jrengineenng.com TABLE OF CONTENTS PAGE ' LETTER OF TRANSMITTAL TABLEOF CONTENTS............................................................................................................... I 1 1. INTRODUCTION.................................................................................................................. I ' 1.1 Project Description......................................................................................................... I 1.2 Purpose and Scope of Report .........................................................................................1 1.3 Design Criteria...............................................................................................................1 ' 1.4 Master Drainage Plan and Related Drainage Reports....................................................2 2. EXISTING SITE DRAINAGE..............................................................................................2 ' 3. PROPOSED DRAINAGE PLAN ................................................ :.........................................2 3.1 Off -Site Flow Routing...................................................................................................2 3.2 On -Site Flow Routing....................................................................................................3 3.3 Storm Drainage Structure Design..................................................................................3 4. 5. WATER QUALITY...............................................................................................................4 EROSION CONTROL .......................................... :...............................................................5 ' 5.1 Erosion and Sediment Control Measures.......................................................................5 5.2 Dust Abatement.............................................................................................................5 5.3 Tracking Mud on City Streets........................................................................................5 5.4 Maintenance...................................................................................................................5 1 5.5 Permanent Stabilization.................................................................................................6 ' 6. 7. SUMMARY...........................................................................................................................6 REFERENCES......................................................................................................................7 APPENDIX A... MAPSAND FIGURES.........................................................................................................8 APPENDIXB........................................................................................................................9 HYDROLOGIC CALCULATIONS.....................................................................................9 ' APPENDIXC......................................................................................................a...............10, HYDRAULIC CALCULATIONS.......................................................................................10 ' APPENDIX D.....................................................................................................................11 EXCERPTS FROM OTHER REPORTS............................................................................ I I ' Drainage and Erosion Control Report Page i Werner Elementary School Site Remodel June 20, 2002 INTRODUCTION 1.1 Project Description ' The Werner Elementary School site remodel consists of the expansion to the south of the existing parking lot, and an addition of a soccer field. These improvements will be constructed on existing residential lots 48A, 49A, 50A and 51A of the Miramont Valley P.U.D. This project will also include the construction of a storm sewer pipe along the south side of the existing school building. This storm drain will replace an existing grass Swale. A HERCP culvert will be added under a new entrance to the school parking lot. An existing ' drainage Swale located in the southeast corner of the site will be replaced with a combination of RCP and HERCP. t 1 1 The site is located in the northeast corner of Roma Valley Drive and Mail Creek Lane in Fort Collins, Colorado, and is bounded by Miramont Valley P.U.D. on the south and east, and by the existing Werner Elementary School site on the north. More generally, the site lies in the southeast quarter of Section 1, Township 6 North, Range 69 West of the Sixth Principal Meridian, in the City of Fort Collins, Larimer County, Colorado. A vicinity map is included in Appendix A of this report. 1.2 Purpose and Scope of Report This report defines the proposed drainage and erosion control plan for the Werner Elementary School Site Remodel. The drainage plan includes consideration of all on -site and tributary off -site runoff. 1.3 Design Criteria This report and associated calculations were prepared to meet requirements established in the "City of Fort Collins Storm Drainage Design Criteria and Construction Standards" (SDDCCS), dated May 1984 and updated January 1997. The new rainfall criteria as amended by Ordinance 42.199 was used for the 10-year and 100-year design storms. Runoff computations were made using the rational method. Where applicable, the criteria established in the "Urban Storm Drainage Criteria Manual" (UDFCD), 1984, developed by the Denver Regional Council of Governments, has been utilized. Drainage and Erosion Control Report Page 1 Werner Elementary School Site Remodel June 20, 2002 1.4 Master Drainage Plan and Related Drainage Reports ' According to the City of Fort Collins Master Drainage Plan, this site lies in the Fossil Creek Master Drainage Basin. The Master Drainageway Planning Study for the Fossil Creek ' Drainage Basin was prepared by Simons, Li & Associates, Inc., dated August 1982. ' 2. EXISTING SITE DRAINAGE ' The proposed expansion lies within existing residential lots in the Miramont Valley P.U.D. The Final Drainage and Erosion Control Study for Miramont Valley, P.U.D. prepared by ' RBD Inc., dated September 30, 1996, and an Addendum to the same report, dated March 2000, was used to determine existing drainage basins and flow patterns. Wherever possible, drainage patterns and structures established in the Miramont Valley P.U.D. were used. The soils on this site are silty clay loams lying on fans, valleysides and ridges, categorized in ' Hydrologic Group C (USDA, 1980). Pertinent characteristics of these soils include rapid to medium runoff, a slight hazard of wind erosion, and a moderate to severe hazard of water ' erosion. A soils map is included in Appendix A ' 3. PROPOSED DRAINAGE PLAN 1 3.1 Off -Site Flow Routing A portion of the existing sub -basin 411 delineated in Miramont Valley P.U.D. will change ' with the proposed grading of the Werner Elementary School site remodel. Basin 411 drains to a 5' curb inlet (design point 411) on the north side of Roma Valley Drive. The area draining to this basin will increase from 1.79 to 2.14 acres, however, the runoff coefficient for this area decreases due to the elimination of 3 houses and driveways (not yet built). The proposed soccer field will replace these hardscape areas. The result is a decreased or equivalent flow value reaching design point 411; therefore, the 5' curb inlet has adequate capacity for the new condition. An increase in flows to the existing 29"x45" HERCP culvert under Roma Valley Drive will ' also occur due to the parking lot expansion. The existing culvert was checked for capacity with the increase in flow. It was determined that the culvert is adequately sized to handle the increase in flow. All hydraulic calculations are included in Appendix C. Drainage and Erosion Control Report Page 2 Werner Elementary School Site Remodel June 20, 2002 3.2 On -Site Flow Routing The site was graded so that stormwater runoff is directed away from the existing school building. A qualitative summarization of the drainage patterns within each sub -basin is provided in the following paragraphs. All hydraulic calculations are included in Appendix C. ' Subbasin 101 is the roof of the Werner School building. In the existing condition, flows from this basin enter an existing 10" roof drain on the south side of the building, and discharge into a grass swale running west. Runoff in this swale then enters an 18" RCP that connects to the storm sewer system running along the west side of Mail Creek Lane, and ultimately discharges into Mail Creek. With this project, the existing 10" roof drain will connect to a new storm sewer pipe at design point 101. The pipe will replace the existing swale. The new storm sewer pipe ' connects to the storm sewer running along the west side of Mail Creek Lane, which will also be improved with this project. Runoff from Subbasin 102 is conveyed via sheet flow over the existing playground ' to the proposed storm sewer pipe running along the south side of the school building design 102. The at point new storm sewer pipe will replace the existing grass swale, and connect to the storm sewer running along the west side of Mail Creek Lane. Subbasin 103 includes the expansion of the parking lot and a portion of the soccer ' field. This basin has been graded to drain to a grass -lined swale in the northwest corner of the parking lot expansion. The proposed swale will provide water quality ' (see Section 4), and discharge into an area inlet that connects to the improved storm sewer system running along Mail Creek Lane at design point 103. ' 3.3 Storm Drainage Structure Design ' Storm drainage structures for this site include storm drainage pipes, a grass lined swale and riprap. For the storm pipe design, the computer program StormCAD, developed by Haestad Methods, Inc. was used. StorrnCAD considers whether a culvert is under inlet or outlet ' control and if the flow is uniform, varied, or pressurized and applies the appropriate equations (Manning's, Kutter's, Hazen -Williams etc). Riprap is sized for the swale section ' of the storm sewer system running along Mail Creek Lane according to the pipe size and the flow conditions at the outlet. Guidelines from the "Urban Storm Drainage Criteria Manual" (UDFCD) were used to design the proposed riprap. Drainage and Erosion Control Report Page Werner Elementary School Site Remodel June 20, 2002 ' A culvert under the new parking lot entrance from Mail Creek Lane will be constructed with this project. Flow values determined in the Final Drainage and Erosion Control Study for Miramont Valley, P.U.D. prepared by RBD Inc., dated September 30, 1996, and an ' Addendum to the same report, dated March 2000, were used to size this culvert. The new storm pipe that drains subbasins 101 and 102, and connects to the existing storm ' sewer system running along the east side of Mail Creek Lane, has been analyzed using flow quantities determined with this report, along with flow values determined in the Final Drainage and Erosion Control Study for Miramont Valley, P.U.D. prepared by RBD Inc., dated September 30, 1996, and an Addendum to the same report, dated March 2000. An ' exhibit that shows flow quantities used for storm sewer analysis is included in Appendix C, and excerpts from the Miramont Valley drainage reports are included in appendix D. J I The existing swale in the southeast corner of the site will be replaced with a combination of RCP and HECRP with this project. An exhibit that shows flow quantities used for storm sewer analysis is included in Appendix C. The location of all storm drainage structures is shown on the Drainage and Erosion Control Plan included in the back pocket of this report. 4. WATER QUALITY Water quality for the proposed parking lot expansion will be accomplished by routing Sub - Basin 103 through a grass -lined swale. Runoff from Sub -Basin 103 is conveyed through a combination of sheet flow and curb and gutter flow to a low point in the northwest area of the parking lot expansion. At this low point, a curb cut allows runoff to enter an 80' long grass -lined swale. This swale then discharges into an area inlet in the proposed storm sewer running along Mail Creek Lane, and ultimately into Mail Creek. The grass -lined swale provides water quality by filtering out small particles during low flow or minor storm conditions. The swale is sized to carry 133% of the major storm. Due to the lack of space on the site, this water quality solution is considered the best alternative. ' Drainage and Erosion Control Report Page 4 Werner Elementary School Site Remodel June 20, 2002 I 1 5. EROSION CONTROL 5.1 Erosion and Sediment Control Measures Erosion and sedimentation will be controlled during construction by inlet filters, silt fences, gravel construction entrances, and seeding and mulching. These measures are designed to ' limit the overall increase in sediment yield due to construction activities 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. The required erosion control escrow is $6,983.25. The erosion control cost estimate, effectiveness calculations and a construction schedule are included in Appendix C. 5.2 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 famish all labor, equipment, materials, and means required. The Contractor shall carry out proper efficient measures wherever and as necessary to reduce dust nuisance, ' and to prevent dust nuisance that has originated from his operations from 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. 5.3 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 ordered 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 Erosion Control Plan, with base material consisting of 6" coarse aggregate. The contractor will be responsible for clearing mud tracked onto city streets on a daily basis. ' 5.4 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. Maintenance ' of temporary erosion control devices is the responsibility of the contractor. ' Drainage and Erosion Control Report Page 5 Werner Elementary School Site Remodel June 20, 2002 d 1 5.5 Permanent Stabilization 1 All soils exposed during land disturbing activity (stripping, grading, utility installations, stockpiling, filling, etc.) shall be kept in a roughened condition by ripping or disking along 1 land contours until mulch, vegetation or other permanent erosion control is installed. No soils in areas outside project street rights of way shall remain exposed by land disturbing 1 activity for more than thirty (30) days before required temporary or permanent erosion control (e.g. seed/ mulch, landscaping, etc.) is installed, unless otherwise approved by the 1 Stormwater Utility. Vegetation shall not be considered established until a ground cover is achieved which is demonstrated to be mature and stable enough to control soil erosion as specified in paragraph 11.3.10 of the City of Fort Collins Storm Drainage Construction 1 Standards. 1 6. SUMMARY 1 The Werner Elementary School site remodel consists of the expansion to the south of the existing parking lot, and an addition of a soccer field. These improvements reduce or replace flows to design point 411 of the Miramont Valley Subdivision by replacing the hard 1 surface area of homes and driveways (not yet built) to landscape area. The addition to the parking lot results in an increased flow into the storm sewer system running along Mail Creek Lane of 0.8 cfs. Existing and proposed storm sewer structures that convey this runoff to Mail Creek have adequate capacity to handle the increase in flows. i 1 1 1 1 1 1 1 Drainage and Erosion Control Report Page 6 Werner Elementary School Site Remodel June 20, 2002 7. REFERENCES 1. City of Fort Collins, "Storm Drainage Design Criteria and Construction Standards", . (SDDCCS), dated May 1984. 2. RBD Inc. Engineering Consultants, "Final Drainage and Erosion Control Study for Miramont Valley P.U.D. Fort Collins Colorado', dated September 30, 1996. 3. RBD Inc. Engineering Consultants, "Addendum to the Final Drainage and Erosion Control Study for Miramont Valley P.U.D. Fort Collins Colorado', dated March 2000. 4. Soil Survey of Larimer County Area, Colorado. United States Department of Agriculture Soil Conservation Service and Forest Service, 1980. 5. Urban Drainage and Flood Control District, "Urban Storm Drainage Criteria Manual", Volumes 1 and 2, dated March 1969, and Volume 3, dated June 2001. Drainage and Erosion Control Report Werner Elementary School Site Remodel Page 7 June 20, 2002 11 1 1 1 1 APPENDIX A 1 MAPS AND FIGURES 1 1 1 1 1 1 1 1 1 i 1 1 1 VICINITY MAP N. T. S. Terra Mh L' __v 0 I SOILS MAP t x u u 0 t 2, 000 4000 3000 2000 1000 0 Scale 1 24000 5000 10000 Feet LARIMER COUNTY ARIA, COLORADO NO. 25 FL OW EXHIBIT ' W Q W V OPB- PROPOSED 19 X30" HERCP 'EX/SANG 24" RCP 1 -YISANG 36" RCP A EX/SNG SCALE 58.60 I EXIST/NG 29-.4! t WERIVER ELEMENTARY SCHOOL 16.3 CFS FROM CA571E RIDGE P. U.D. SITE REMODEL DRAINAGE REPORVJM/RAMONT VALLEY MARCH 22, 2002 I \ ++I ! casTt� R�OGErIJ.D , I ' 6.5 CFS FROM DESIGN POINT 5 OF ' CA571E RIDGE P.U.D (M/RAMONT VALLEY DRAINAGE REPORT) `Q I \ NOT TO SCALE I I I F � l r J � J 8 34 CFS FROM NORTH SCHOOL BASIN i (MIRAMONT VALLEY DRAINAGE REPORT) I ♦�♦ EX/SANG 24" RCP- / - / 1 I I I I 31. 141 CFS INTO PIPE' TI EX/SANG BASIN BOUNDRY (TYP.N, i i DPA n assco IGIL PVAUI SHALE ' DPC-PROPOSED 4.76 CFS (FROM I I I WMER ELEMENTARY SCHOOL I I I � I L______ @26 -- 12.35 CFS (FROM BAS/ l 101) ' ` 1 103 `-----------I- 9POSED 24" RCP FCP129 X45 WERC'P OPA- ✓N 103J PROPOSE \ 18" RCP ♦ \ �� EX/ ANC 411 ♦\v �\ 1.70Ac J ® -4-. 10.41 CFS (FROM BASIN 102) I I I I I I I I I I I I I I I I I PROPOSED BASIN SOUNDRY (TYP.)\ I I I I %i1/i(aA1J/�/T 1�ALL Y 11 1 i 1 1 H 1 i i 1 1 1 i i i i 1 APPENDIX B HYDROLOGIC CALCULATIONS L � § » m § dE < /�:D.. u0 o64o< .ja.u0 k )j( 0 « k §§§ f « cq / i 6 } k 2§/ { k ui ®°° J $S3 Q »S3 ! m y;Q /.0 §)) �2 2 » I LJ I 1 1 I I 1 RUNOFF COEFFICIENTS & % IMPERVIOUS LOCATION: Wemer Elementary PROJECT NO: 39342.00 COMPUTATIONS BY: M. West DATE: 2/25/2002 Recommended Runoff Coefficients from Table 3-3 of City of Fort Collins Design Criteria Recommended % Impervious from Urban Storm Drainage Criteria Manual Streets, parking lots, sidewalks Lawns (flat <2%, sandy soil) Roofs Lawns (flat 2 to 7%, heavy soil) Runoff % coefficient Impervious C 0.95 100 0.10 0 0.95 90 0.25 1 0 JR Engineering 2620 E. Prospect Rd., Ste. 190 Fort Collins, CO 8525 SUBBASIN DESIGNATION TOTAL AREA Ise.) TOTAL AREA (sq.ft) ROOF AREA (sq.ft) PAVED AREA (sq.ft) SANDY AREA (sq.ft) LANDSCAPE AREA (sq.ft) RUNOFF COEFF. (C) % Impervious 101 1.23 53,645 53,645 0 0 0 0.95 90 102 3.26 141.905 0 30,630 22,750 88.525 0.38 22 103 1.10 48.005 0 15,558 0 32,447 0.48 32 Equations Calculated C coefficients & % Impervious are area weighted C = E (Ci Ai) / At Ci = runoff coefficient for specific area, Ai Ai = areas of surface with runoff coefficient of Ci n = number of different surfaces to consider At = total area over which C is applicable; the sum of all Ai's 1 flow-fteollins.xis } 00 ' oU LL QO m CWC C F 1 E v N wo Ync O n U ' r C] z �O ' V F' ccl a O a O Q _ O. U 0 N co K Q W C o r m _ E LL uir m m.S n 2 v E L lu m C ` J N � M yUj 2 m N m N ah N N u O 0 0 LL c E o J Q N N W Q_ U o m N co c w m i f N N N i7 O o� N O N v W O O N F r' F O m Q O n d O O Ill fV O O 00 L N N J C N m Vn vG W 0 O C G O W � Z _ r N N N N o W d W N N Z Q O O O m m N 2 H Q lz N 11-1-1-11 0) R W a N O � E U 1 � e § ,) �z sv kk k§ ■ � § °_; ƒ, ff § § !!F maw s § �fE °N! :::00 }�, a \ 3 3 { / 2 k 0. 2 [ `LL k f� LU 2E ) M{ m to =$ \ k w 3� / E co \ / j / ! ( ( $ y){ [ /)�.. j8\4 §//j \ e I{{E aZ\ ~ kZ)«/ £a &; ; _{_ i LL 7 $co § c- 0: f0 ° ( © LU kE�EE z ) [. k �w R � k§ ƒk« § s � z ��k\ a�N� JR Engineering 2620 E. Prospect Rd., Ste. 190 Fort Collins, CO 80525 RATIONAL METHOD PEAK RUNOFF (City of Fort Collins, 2-Yr Storm) LOCATION: Werner Elementary PROJECT NO: 39342.00 COMPUTATIONS BY: M. West DATE: 2/25/2002 2 yr storm, Cf = 1.00 DIRECT RUNOFF CARRY OVER TOTAL 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) 1 101 1.23 0.95 5.0 2.85 3.33 3.33 2 102 3.26 0.38 13.7 1.94 2.39 2.39 3 103 1.10 0.48 11.8 2.08 1.09 1.09 Q=CfCiA Q = peak discharge (Cfs) C = runoff coefficient Cf = frequency adjustment factor i = rainfall intensity (in/hr) from City of Fort Collins IDF curve (4/16/99) A = drainage area (acres) i = 24.221 / (10+ tc)" flow-ftcollins.xls [] LOCATION: PROJECT NO: COMPUTATIONS BY: DATE: 10 yr storm, Cf = RATIONAL METHOD PEAK RUNOFF (City of Fort Collins, 10-Yr Storm) Werner Elementary 39342.00 M. West 2/25/2002 1.00 JR Engineering 2620 E. Prospect Rd., Ste. 190 Fort Collins, CO 80525 DIRECT RUNOFF CARRY OVER TOTAL Design Point Tributary Sub -basin A (ac) C Cf tc (min) i (in/hr) Q (10) (cfs) from Design Point Q (10) (cfs) Q(10)tot (cfs) 1 101 1.23 0.95 5.0 4.87 5.70 5.70 2 102 3.26 0.38 13.7 3.32 4.08 4.08 3 163 1.10 0.48 11.8 3.55 1.86 1.86 Q=CrCIA Q = peak discharge (cfs) C = runoff coefficient Cr = frequency adjustment factor i = rainfall intensity (in/hr) from City of Fort Collins IDF curve (4/16/99) A = drainage area (acres) i = 41.44 / (10+ tc)07974 flow-ftcollins.xls LOCATION: PROJECT NO: COMPUTATIONS BY: DATE: 100 yr storm, Cf = RATIONAL METHOD PEAK RUNOFF (City of Fort Collins, 100-Yr Storm) Wemer Elementary 39342.00 M. West 2/25/2002 1.25 JR Engineering 2620 E. Prospect Rd., Ste. 190 Fort Collins, CO 80525 DIRECT RUNOFF CARRY OVER ITOTAL Des. Point Area Design. A (ac) C Cf tc (min) i (in/hr) Q (100) (cfs) from Design Point Q (100) (cfs) Q(100)tot (cfs) 1 101 1.23 1.00 5.0 9.95 12.25 12.25 2 102 3.26 0.47 13.7 6.78 10.41 10.41 3 103 1.10 0.60 11.8 1 7.25 4.76 4.76 Q=CiA Q = peak discharge (cfs) 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+ tc)0.7975 flow-ftcollins.xls I [_1' d 11 1 1 11 HYDRAULIC CALCULATIONS STORM PIPES, SWALES, RIP -RAP, AND EFFECTIVENESS CALCULATIONS F LL Z_ LL J V/ N O U d � U v � N (p X M W X W o m m N 0 N N 19 O 1 11 CO N 0 N (0 O n m cD Oi 01 Oi Oi 0 Q>v E m v m m oiM N M d j^ N N N - C 0 3U 0 7 O nll� N O (m0 M ll� N m (0 to M a v M M N J o) C9 C N N N N N N N N N 0) 0) 0) W 0) O W O 0) 0 0 O M N c M CO M M (0N Co. y D 0 (0 M N N N N O C C> N N N N N N N N N m 0) m 0 0) 0) m O W O W O E - o o y J uOi (o (mO uni COmu°i co (o ao u) (ri v v m wi (� N N N N N N N N N m O 0) m 0) 0) 0) 0) 0) v v v v v v c v E 0 m p 100 N N N M N (D N 0 QU E C O r v m m o(M r m O f` n m m D Q N M m (O t` M LO N N N N `)>> ON) m m m m m m m m n m v v v v v v v v v W 0) M N O) .T. _ N m M m 0 O QO U O N M N (n Ih o N N m M o m m M Uv 4) v m 0 0 0 o m (O rn a m CO m CO m (O m N m m m N m r O O N M m m r m m v o m N ) o N O O O O N 0 U L O f` m m N N m O m c V a (mO o M a v (n r` CO J M to 0 E� z rU) n c U U U N c c U U U U U U 0 N U) 10 (0 C C C C C C C v v N m v v (O m m (O m rn N N M M M M N N H O. w U N U W N co i awa-wwn.aaw E Z i 1 1 i i 1 1 1 1 1 i i 1 1 L 1 PIPE B Outlet Project Title: Werner Elementary Project Engineer: M. West 1 x:\3930000.all\3934200\drainage\pipe b.stm JR Engineering Ltd StormCAD v1.5 ]158] 04/18/02 09:14:31 AM ® Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA (203) 755-1666 Page 1 of 1 u E From Parking Lot basin 103 ' Worksheet for Triangular Channel \NNJF-Z- QQNOT� 5WAL125 ' Project Description Project File x:\3930000.all\3934200\drainage\new swal.fm2 ' Worksheet Flow Element Werner Elementary Triangular Channel Method Manning's Formula Solve For Channel Depth 1 Input Data ' Mannings Coefficient 0.030 Channel Slope 0.8000 % Left Side Slope 4.000000 H : V Right Side Slope 4.000000 H : V Discharge 6.33 cfs ' Results Depth 0.81 ft Flow Area 2.65 ft2 t Wetted Perimeter 6.72 ft Top Width 6.52 ft Critical Depth 0.69 ft ' Critical Slope 0.019476 ft/ft Velocity 2.39 ft/s ' Velocity Head Specific Energy 0.09 0.90 ft ft Froude Number 0.66 Flow is subcritical. IJ 1 I 1 '04/22/02 FlowMaster v5.15 04:16:14 PM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 I I � � Ak 7 tr 0 w� i2 )�k § ƒ LL ca _ o� } > o m� CL @ }7 )�� w w § D/ % / § ] § k S / 8 — J k & S _2 > Q u } � § = 0 j k / ~ u 0 0> e ° c G G > 2 2 co § cc @ a) & o 7 / 0 a), �)� k ) \/k© cow tE . _ \ �> f __ %»CL m I ! o u a = 2 CY j } / \ \ ? . & , £ t) )C �2� / / k/$ �� ) 2 7§//k )k E a \ k k} 2\k{ Z0 \�\\.} §�£ @ —)5!2a . LU U)� §)/k /ocy e @� )( ■ Q m \� �0) A� \ §k co k § 2 e « In ono§ 2© ƒ uvo Lf q co \ (L \ CL ƒ X � / § / ƒ co E @ { CL co }ƒ tME § �f— a ° o 0 ®� a k \$�fn o �S��� . = o _ LO § 2 !M(n G��� 2 c \ . 0 � 0 2 �- § - a CL _ �caG ,2��2 � q: [ƒo � 7 oo� a !aa _ G �(/� /2¥ " a ® z 7 11 , > , rx a)¥ � 0 2�LnE ® § ��/� - §0 2 §) fk 2 m# 0�= AE E )z \04 = 0 5 e E . ƒ� ¢ S B « §�®�°� o w f@%«$ � �� ' u z aaU)B �k5§�ƒ m �zz �a»w i=- )f §{{ ,, /_ \ ���K A(oa=p ° k � .m Q2 z §( gM q# B k § k ) § \§k§ k w Ei qt0$ Lƒ ° i / ) 2 ƒ & I I JR Engineering, Ltd. 2620 E. Prospect Rd., Ste. 190, Fort Collins, CO 80525 1 1 1 1 1 RAINFALL PERFORMANCE STANDARD EVALUATION PROJECT: WERNER ELEMENTARY SCHOOL SITE REMODEL STANDARD FORM A COMPLETED BY: M. WEST DATE: 26-Apr-02 DEVELOPED ERODEBILITY Asb Lsb Ssb At " Li Ai • Si Lb Sb PS SUBBASIN(s) ZONE (AC) (FT) (%) (FT) (%) (%) 101 MODERATE 1.23 270 0.5 332.5 0.6 102 3.26 670 2.0 2192.7 6.5 103 1.10 325 1.5 358.2 1.7 Total 5.59 2873.33 8.78 514 1.6 79.6% 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% of the rainfall sedimentation that would normally flow off a bare ground site during a 10-year, or less, precipitation event. 1 C 1 1 1 1 1 1 1 1 ' Erosion.xls 1 1 t 1 1 1 L 1 JR Engineering 2620 E. Prospect Rd., Ste. 190, Fort Collins, CO 80525 EFFECTIVENESS CALCULATIONS PROJECT: WERNER ELEMENTARY SCHOOL SITE REMODEL STANDARD FORM B COMPLETED BY: M. WEST DATE: 26-Apr-02 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 = I-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) 101 1.23 ROADS/WALKS 0.00 Ac. ROUGHENED GR. 1.23 Ac. STRAW/MULCH 0.00 Ac. GRAVEL FILTER NET C-FACTOR 1.00 NET P-FACTOR 0.36 EFF = (I-C*P)* l00 = 64 0% 102 3.26 ROADS/WALKS 0.70 Ac. ROUGHENED GR. 0.00 Ac. STRAW/MULCH 2.55 Ac. GRAVEL FILTER NET C-FACTOR 0.05 NET P-FACTOR 0.80 EFF = (I-C*P)* 100 = 96.1 % 103 1.10 ROADSIWALKS 0.36 Ac. ROUGHENED GR. 0.00 Ac. STRAW/MULCH 0.74 Ac. GRAVEL FILTER NET C-FACTOR 0.04 NET P-FACTOR 0.80 EFF = (1-C*P)* 100 = 96.5% TOTAL AREA = 5.59 ac ' TOTAL EFF = 89.1% ( E (basin area * eff) / total area REQUIRED PS = 79.6% Since 89. 1% > 79.6%, the proposed plan is o.k. ' EROSION.XLS EROSION CONTROL COST ESTIMATE JOB NAME: WERNER ELEMENTARY SCHOOL SITE REMODEL COMPLETED BY: JOB NO. 39342.00 DATE: EROSION CONTROL MFASTTRF.S M. WEST 4/26/2002 ITEM DESCRIPTION UNITS I UNIT COST lQUANTITY I TOTAL COST 1 TEMPORARY SEED & MULCH ACRE $ 655.00 1.3 $ 851.50 2 SILT FENCE LF $ 3.00 768 $ 2,304.00 3 GRAVEL CONSTRUCTION ENTRANCE EACH $ 500.00 2 $ 1,000.00 4 INLET PROTECTION EACH $ 250.00 2 $ 500.00 5 1 STRAW BALES LF $ 3.25 0 $ - 6 1 SEDIMENT TRAP EACH 1 $ 500.00 0 $ COST $ 4,655.50 CITY RF.SF.FDfNGCnSTFOR TOTAT RTTFARRA ITEM DESCRIPTION UNITS I UNIT COST lQUANTITY I TOTAL COST 1 RESEED/MULCH ACRE $ 615.00 5.6 1 $ 3,438.62 ' COST $ 3.438.62 SECURITY DEPOSIT $ 4,655.50 REQUIRED EROSION CONTROL SECURITY DEPOSIT WITH FACTOR OF 150% $ 6,983.25 0 099W I . W. EXCERPTS FROM OTHER REPORTS L 1 low ;;z Addenda*m to the Final Drainage and Erosion -,.,.Control Study miramont.Val.ley PX.D., Fort Collins,. Colorado THE SEAR -BROWN GROUP Standards in Excellence a Basin 412 has the biggest changes which include increased area, addition of a culvert with riprap under Roma Valley Drive, and reshaping the borrow ditch along Mail Creek Lane, and realignment of the existing 24" CMP from the school site. The area of Basin 412 increased from 1.35AC to 1.50AC which will increase flows to the borrow ditch. The flows to the north of Roma Valley Drive will sheet flow into the borrow ditch. The developed flows from Roma Valley Drive will be conveyed via the proposed curb & gutter to the 6' cross -pan along Mail Creek Drive and ultimately into the borrow ditch. The culvert under Roma Valley Drive was calculated using information from the Final Drainage and Erosion Control Study for Castle Ridge @ Miramont P.U.D., First Filing, and the Drainage Report for Poudre School District R-1, Werner Elementary School (see appendix pg 17). It was determined that the expected 100 year flow through the borrow ditch and culvert would be 57.8 cfs. The sum of the following individual flows equals the expected 100-year flow. Flows expected from the detention pond in Castle Ridge are 16.3 cfs (see appendix pg 18). A flow offL5-cfs is expected from the design point 5 in Castle Ridge P.U.D. (see appendix pg 17). A flow of 31.0 cfs is expected from the Werner Elementary School site (see appendix pg 19). Finally, 4.0 cfs is expected from Basin 412 of the Miramont Valley P.U.D. The size of pipe required to carry this flow is a 36" RCP (see appendix pg 16) with flared end sections on each end. An equivalent 29"x45" elliptical RCP (Class III) will be used so that the pipe is sufficiently below the curb and gutter. The riprap required on the downstream side of the culvert is to be Type VL (Class 6) riprap at 17 ft long, 9 ft wide, and 1 ft deep (see appendix pg 22). The same riprap configuration will be used downstream of the realigned 24" CMP. The borrow ditch will be regraded such that the longitudinal slope upstream of the culvert is 1.5 % for 100 feet and downstream is 1.5 % for 125 feet. Using the freeboard adjusting factor for flow it was determined that the maximum depth upstream is 2.30 ft which is below the 3 ft depth as provided by the regrading as shown in the plans (see appendix pg 27). The maximum depth downstream is 2.30 ft which is below the 4 ft depth as provided by the regrading as shown in the plans (see appendix pg 26). Significant erosion has occurred where the borrow ditch enters Mail Creek. To remedy the situation a new 36" ADS-N12.pipe will be installed with headwalls at each end. There will be riprap placed downstream to prevent erosion of Mail Creeks banks. D. Conclusion The proposed drainage concepts presented in this study and shown on the revised final utility plans adequately provide for the conveyance of developed runoff from Miramont Valley P.U.D. The concepts shown here will also allow for the development to occur and be in compliance with the Fossil Creek Basin Master Plan, and the Mail Creek Master Plan. This site will also be in compliance with the Overall Drainage plan for the Oak/Cottonwood Farm. No Text I i 191 N__ `s I ENsnxc pIT I I I / II p H---ex / I \\ ° III— j i Is vI — I COSTING zA RCP-,j I i I I I M KN GTF N NACE JICIXN BDL M115E _.. _ / zEF RTK Ma MFEr � :.. LVMY4- RP IONIC , e v IQ z Foor AID : - vuzEr �� -- N TO INA ICT DEAN i (sLE OCTAL SHEET) "� °"aP°tm EWME - ScE mmrx YCMII A -A MD EXI]P�G .16-AD CP roAexWo IEIIa•E RS Ab CW[Cl E •. r I� OCTAL SHEET CIi SEE SHEET C7 FOR CONTINUATION I 4�111' l F\ \ I I y /,1 `\I EwSnxT. yC RCOF ORu IT _ -4929493 _ 928 T492( \ --- ----- _ -- -_--77 928- i" VALLEY tit,i /- k90 q' 11 AtWAYMr YALLEY \ 00 // IIII /' / / >/ oy It I a m Ell 492 / I 1.50AC / \ DRAINAGE SUMMARY ABLE DxxlBn Polnl THWt>7 sut-BmM AnN (ao) C (10) C (1m) tc (z lO t ) (mN) 0(2)W (M) 10)NE (cM1) a(1W)19t (eN) 1 101 1 1.23 1 Dw 1.W 5.0 1u sM IzzS z 102 1 0.20 1 0.]9 a47 117 2 4.m 10.41 ] 10] 1.10 O.AB 0.fi0 11.0 1.OP 1.00 4." LEGEND — — EYJSTMG BASIN BOUNDRY vy- \,1^Y SET FORCE — — PROPOSED BASIN BOWERY PROPOSED 1' WNTWR ® CONSTRUCTIIXI ENTRANCE PROPOSED 5' CONTOUR EXISTING 1' CONTOUR RIPRAP EXISTING 5' CONTOUR e EOMBASIN / AREA EXISTING STORM SEWER PROPOSED STORM SENER Q DESIGN POINT © INIFT PROTECTION --- EXISTING EDGE CE ASPHALT FES PLANED END SECTION / 30 15 0 30 60 SCALE: 1"- 30' CONSTRUCTION SEQUENCE km O.gt Lv= Tim 9 �� AAAaNN wNm :uuo rr Z1.1EJOOOMED4� Orrcxma Nrt sumamum 4mm AXFxmlc N ON a FmT o SON. _ IN PLACE BOX DEi IOw N. ,M Ate= 4] 1 (3y of Fart WHO& Colorado 1-I UALITY PLAN APPROVAL RENEN£D BY: FpyEp ypq M vYiF VGLO.M T APPR014D: my NOTES LARNEIi Cg Y EHMFENIO DATE CHECKED BY: L YE DETAIL BEET FOR BEST MARA1a1ENT PxAVII¢S ROADS) FOR law At vcwmwm m WARY We ME IARIYER COUNTY RENEW CCN iI11E5 CgIPWNCE KITH THESEFR�ON STANDARDS. RENEW By THE COUR DOES NOT CONSTITUTE APPROVAL OF z ILL NMx ME PROPERTY MUST BE CHECKED BY: ME PLAN DESIGN. ACCORDANCE N ACMWANS MPI PdARE SWIXA DSTECL TECHNICAL OHOC UONCTT Slmmm MIRY De SCECi1GTMi "M LOyEN3 N1NN ME FMNL-6-WAY YIISi BE �T gxIFpNN1L£ LWASS. -R EL�Gi)vE NG CHECI(ED BY: MIS RENEW DOES NOT C ICH MA I NHICH MA REMEW/APPROVALIMEK OF ANY PRIVATE BE SH MESE PLANS 1 YE DxyM¢ 91EEL CT FOR WOOL ) CITY OF Pvxa k xsFaolkn Oob TO BE F ENTS INTFNGED i0 BE FOR COUNTY REN INTEON-NDED ARE W OF PUBIIC IMPROVEMENTS PUBLIC M ADJACENT E1103M IND SEdYENi gNW0. CIXISIRUCTLN PVN XDIFS A901iyalINWN AL coca PI -Am HOME, TO PROPERTYIONFEE CONSUNIX ON -SITE PRIVATE IMPROVEMENTS I IMPROVEMENTS CHECKED BY: NO CANNOT COMMENCE UNIX ALL RE OMMERC ALL IRED NAND OR $NDT(5). 20 W REOW � BIE ED,Fl4 CAlfa EI0i TmNN D,~ � DEPLETE, ENT SON EVENS AL REM AND BOIL PERMIT(S) p1EG1(ED BY: MEFINA ROVED A). ME COMPLETE, gPP120YID AND ql COUNTY. LOU NM LARIMER COUNTY. LOR. 9q-19FB®FFdC $1B-I9F-0YA�am °oI' ON Bexvs of n DwxmexD I _ M* LO c co Ea .3 ca — 0 •EO o C ®.0 too U. MO., 39342.00 WR BY, MW ORAL% PNO I EROSION CONTROL PLAN CV i �✓j ` \ ' �\• ��1 ^ `IJ'l '_�'..\ \.\\ CASTLC A2/pGEP.&I j 494r V\�ll-�� Ani \ G� 1 I 1 DRAINAGE SUMMARY TABLE Ocay� PWnI TrEu,wy SPO-bmF ALm (ac) C ,a ( G ,N ( ) tc 2 10 &Y00 ( . i min (min) 2 , a is left) ch 1D ,uL a ) cls ( ) ,CO ,uL a > cM1 ( ) i 101 1.2J 0.95 too SO 3.33 5.70 12.24 2 1W 12! 0. M47 IS] 239 4.OB 10.41 J t03 Lt0 ` 0.4p too 11.e 1.09 1 AS 4.76 Wit,, \ \ (� It II A 1It I \ \ t 1 11 Ir I A It 11 11 \ I I I I I I I I I I I �I I I t. LEGEND THE CITY OF FORT COLORS SriRMWAIER DEPAR ANT ENRON CONTROL INSPECTOR MUST BE NOBFISD AT LEAST 24 HOURS PRIOR TO MY CONSTRUCTOR P1 THIS SITE. ALL REWIRED PREMIUMS METFUNDING SHALL BE INSTALLED PRIOR TO ANY "NO MILBERG ACTNTY (STOCXRUNG 51MITTRI DEMAND, ETC), ALL OTMR REWIRED EROSIGN CONTROL MEASURES SHALL BE INSTALLED AT ME APPRgWAGE TIME W ME CONSTRUCTION SEQUENCE AS INDCATED IN ME MPAOYED PHHO.ECi SCXEOVHF. Cp151MICng1 PLANS AND EROSION CONTROL REPORT. PRE -DISTURBANCE VEGETATION SHALL BE PROTECTED AND RETAINED yMEREYFA POSSUM. REMOVAL OR DISTURBANCE OF EASTING VEGETATION SHALL BE LIMITED TO ME AREA RECLINED FOR IMMEDIATE CONSTRUCTOR OPERATIONS AND FOR ME S HLWT UST PRACTICAL PERIOD or TIME. ALL SOLS EXPRUBM WRONG µY DISTURBING ACnNn (STRIPPING. CARDING. JIMTY INSTALunGNS. STOCKPILES PILLING. ETC.) SHALL BE KEPT IN A ROUGHENED CONDITION BY RIPPING OR SOWS ALONG AND CONTOURS UNTIL MULCH, VEGETATION. SW, SEEDING AND MULCHING. W OTHER PERMANENT EROSION CONI IS INSTALLED. NO CUTS IN AREAS OUTSIDE PROTECT STREET RIGHTS OF WAY SHALL BEHAN EXPOSED BY LAND DISTURBING ACRNTY FOR MORE MAN THIRTY (,W) DAYS BEFORE REWIRED TEMPORARY CR PERMANENT EROSION CONWO (EG. SEED/MULCH, LANDSCAPING, ETC.) IS INSTALLED. UNLESS OMFRM3 APPROVED BY ME STOHMWAIER DEPARTMENT WE LANDSCAPE PUN FDA SEEDING/XCONG LIMITS AND INUNDATOR RUN FOR SPRINKLER SYSTEM BLOCK ME PROPERTY SHAI BE WATERED AND UNFUNDED AT ALL ITEMS DURING CWSITUCTON ACIRM S SO TO PREVENT MNB-CAUSI D EROSI ALL TANG DISTURBING ACnMnES SHALL BE IMMEDIATELY ORCGHTMUEG MEN FUO PIE DUST IMPACTS ADJACENT PROPERTIES, AS DETERMINED BY ME OTY Of FORT COLONS ENGINEERING DEPARTMENT. ALL TEMPORARY (STRUCTURAL) EROSION COAMS, MEASURES WALL BE INSPECTED AND REPAIRED OR RECONSTRUCTED AS NECESSARY AFTER EACH RIMOF EVENT IN ORDER TO ASSURE CONRYO D PERFORMANCE of THEIR INTEI FUNCTION. ALL RETAINED SEMI PARTICULARLY THOSE ON ARA S ROADWAY SURFACES. SHALL BE RUMORED AND LVSPOSEO BY IN A MANNER AND LOI SO As NOT RI CAUSE THEIR RELEASE INTO ANY DRAINACFWAY. No ME STOCKPILE SHALL EXCEED HER (1O) EMT IN HEII ALL SOL STOCKPILES sHKL SE PROTECTED FROM SEDIMENT TRANSPORT BY SURFACE ROUGHENING, WATERING AND PERIMETER SALT PENDING. ANY SM STOCKPILE REMAINING AFTER W DAYS SHALL BE SEEOEG AND MULCHED. DTY ORDINANCE PRCHMUS ME TRAGMNG, ONWARD. UP DEPOSITED OF SOL5 M ANY OTHER NATIONAL ONTO CITY STREETS BY OR FROM ANY VEHICLE. ANY INADVERTENT DEPOSITED NATURAL SHALL BE ClEA1FD IMMEDIATELY BY THE CONTRACTOR. _1_-- — — — _ _ \ a R—II\\L---4935 �'_ \\\ .I\ �\\ \\ \ \\� M 15 0 B0 80 ----------'MINT_ --_ _� _ —_ \ \+yu� \ \` \ `ay24 REP v ----------------a _ Kip5_ SAID, - - _ ..__ _ -- _.. .. POIADRE I D/57R/CTR—YIII \\ ' III J� \---1 ` -� 1-__`r_______________ �I\ ��I i t T Itll Tall—� T\ � \I'_ ­7`I I I iiilillil ° I� I I I11 1_ \ = Ij II Ih0 �\ _IL It I 1 \ I \ r I VALLEY GUTTER SEATO DRUM TO SMAME I' (SEE METAL sPE7 I vUP 1 c'� It III I I I i-1 T • EXISTING BASIN BOUNDRY © INUEJ PROTECTION PROPOSED BASIN BOUNDRY SHUT FENCE PROPOSED 1' CONTOUR PROPOSED 5' CONTOUR ® coNSMucnoN ENTRANCE - - EMSIENG 1' CONTOUR RIPRAP EXISTING 5' CONTOUR EXISTING STORM SEWER Is SUOBASHN / AREA PROPOSED STORM SEWER Q DESIGN POINT - - - - -- - E%IS11NG EDGE OF ASPHALT ` 1 1 , 1 , 1 1 1 1 1 I \Yy. Ir 1 vYl , 1 NOTES H SUE DETARL S EEF FOR BEST MANAGEMENT PRACTICES RM PAS) FM U09ON CMMOL, 2, ALL HMFPOYSRHrs MORN ME RNOO DLSTMcr PRMUIY MOST ME IN ACCORDANCE MM PWOE swan USRXCT TECHMCLL SPEORCAnwS. wPROVaRHT$ WITHIN ME RIGHT-OF-WAY MUST BE IN CONFORMANCE MM LWASS. 1 SE UNMADE SHEET CS FM STANDARD OW OF FONT COLONS WASnNCnM SEQUENCE GRANT, lIII I \\ II 11111111 \ \` I I I IIII II II I n 1 II,I III III \ I I � I III III 11 \ I WERNER ELEMENTARY I• >10OL p I \ Ilk f ill '�. � Y� I L101 City of Fort Collins, Colorado UTILITY PLAN APPROVAL RENEN£0 BY: �NI Wy EnpFw CHECKED BY: _ Wm. t WMHH..ols uaxy CHECKED BY: Slwmw,a V\Mly CHECKED BY: _ Paha M Rgwllm CHECLB=O BY: _ TOM, E gns CRECHYD BY: DATE COMPLIANCE MYTH THESE NOT CONSTITUTE APPROVAL Or THIS RENEW ODES NOT CONSTITUTE R1"M W/APPR ON-STE IMPROKMENTS WNIw MAY HOWN. T INTENDED TO BE FOfl COLONY RENEW PUBLIC TO ME PROPERTY. CONSTRUCTION OE -SITE PI CANNOT COMMENCE UNTIL ALL REWITRAFFIC FINAL CEMELOPMENi PLANS(S). SPECKEVIEWS ARE COMPLETE APPROVED ANO ON Fl UM A DULANEY architecture &SIB Santa FM OHM UTILITY PLANS IJOB NO, 39342.00 I DRAWN BY, MW CHECKED BY. JET