Loading...
HomeMy WebLinkAboutDrainage Reports - 02/04/1998PROPMTY OF- _ FORT coill''r4s�� .� r FINAL DRAINAGE AND EROSION CONTROL REPORT D)i�}. OGT 8 199? RESIDENCE INN @ OAKRIDGE PUD FILING 25 OAKRIDGE DRIVE EAST OF LEMAY AVENUE FORT COLLINS, COLORADO 1 1 1 1 1 1 1 1 1 1 1 1 1 FINAL DRAINAGE AND EROSION CONTROL REPORT RESIDENCE INN @ OAKRIDGE PUD FILING 25 OAKRIDGE DRIVE EAST OF LEMAY AVENUE FORT COLLINS, COLORADO Prepared for: Everitt Enterprises, Inc. A Colorado Corporation 3000 South College Avenue Fort Collins, Colorado 80525 Prepared by: JR Engineering, Ltd. 2620 E. Prospect Rd., Ste. 190 Fort Collins, Colorado 80525 (970)491-9888 March 17, 1997 Revised: April 30, 1997 Revised: September 9, 1997 Revised: October 24, 1997 Job Number 9097.01 9 I 1 1 J JREngineering, Ltd. 2620 East Prospect Rd. Suite 190 Fort Collins, Colorado 80525 (970) 491-9888 • FAX (970) 491-9984 www.jreng.com October 24, 1997 Mr. Basil Hamdan City of Fort Collins Stormwater Utility 235 Mathews Street Fort Collins, Colorado 80524 Re: Revised Final Drainage and Erosion Control Report ' Residence Inn @ Oakridge PUD Filing 25 Fort Collins, Colorado ' Dear Basil: JR Engineering, Ltd. is pleased to submit the attached revised Final Drainage and Erosion Control ' Report for Residence Inn @ Oakridge PUD Filing 25 for your review and approval. This report addresses Stormwater's review comments of October 15, 1997. The hydraulic and hydrologic ' evaluation of the site was performed in accordance with the specifications set forth in the City of Fort Collins' "Storm Drainage Design and Criteria Manual". ' If you have any questions regarding the procedures, methodology, or results presented herein, please do not hesitate to contact us at your convenience. ' Sincerely, JR Engineering, Ltd. 1 Do REG/ST F. Scott Waterman, P.E. o� ya0r'T'••.F9 Project Engineer vv�°�' ' =c 31765 ir 90 ' Attachment �SSl NAN-�a 1 1 4935 North 30th Street 6020 Greenwood Plaza Blvd. 704 Fortino Blvd. West Colorado Springs, Colorado 80919 Englewood, Colorado 80111 Pueblo, Colorado 81008 (719) 593-2593 • FAX (719) 528-6613 (303) 740-9393 • FAX (303) 721-9019 (719) 583-2575 • FAX (719) 583-8119 I 1 1 1 1 t FINAL DRAINAGE AND EROSION CONTROL REPORT RESIDENCE INN @ OAKRIDGE PUD FILING 25 OAKRIDGE DRIVE EAST OF LEMAY AVENUE FORT COLLINS, COLORADO Prepared for: Everitt Enterprises, Inc. A Colorado Corporation 3000 South College Avenue Fort Collins, Colorado 80525 Prepared by: JR Engineering, Ltd. 2620 E. Prospect Rd., Ste. 190 Fort Collins, Colorado 80525 (970)491-9888 March 17, 1997 Revised: April 30, 1997 Revised: September 9, 1997 Revised: October 24, 1997 Job Number 9097.01 ' CERTIFICATIONS OWNER ' Everitt Enterprises, Inc., a Colorado Corporation, hereby certifies that the drainage facilities for Residence Inn @ Oakridge PUD Filing 25, shall be constructed according to the design presented in this report. I understand that the City of Fort Collins does not and will not assume liability for ' the drainage facilities designed and/or certified by my engineer. I understand that the City of Fort Collins reviews drainage plans pursuant to Colorado Revised Statutes Title 30, Article 28; but cannot, on behalf of Everitt Enterprises, Inc., guarantee that final drainage design review will absolve ' the Residence Inn @ Oakridge PUD Filing 25 and/or their successors and/or assigns of future liability for improper design. I further understand that approval of the Final Plat and/or Final Development Plan does not imply approval of my Engineer's drainage design. ' Everitt Enterprises, Inc. [1 ' I hereby certify that this report for the Final Drainage and Erosion Control Report for Residence Inn @ Oakridge PUD Filing 25, was prepared by me or under my direct supervision in accordance with ' the provisions of the City of Fort Collins STORM DRAINAGE DESIGN CRITERIA and CONSTRUCTION STANDARDS for the owners thereof. I understand that the City of Fort Collins does not and will not assume liability for drainage facilities designed by others. ' Respectfully Submitted, ' O. •• OTT '•. Frederick Scott Waterman, P.E. Uo.,:•���,�s� �sa•;�o ' Colorado Professional Engineer No. 31765 -0 31765 For and On Behalf of JR Engineering, Ltd. 9 �:��u°Ci 0•c • •''•••.....•••' • \�. ' �SS�ONAL��� 1 I 1 1 TABLE OF CONTENTS PAGE TABLE OF CONTENTS....................................................... ii INTRODUCTION 1.1 Project Location...................................................1 1.2 Site Characteristics................................................. 1 1.3 Soils ------------------------- t 1.4 Purpose and Scope of Report .........................................2 1.5 Design Criteria....................................................2 1.6 Master Drainage Basin .............................................. 2 2. HISTORIC (EXISTING) DRAINAGE ....................................... 2 3. DEVELOPED FLOWS ................................................... 3 3.1 Method..........................................................3 3.2 Exterior Flows....................................................3 3.3 Onsite Flows......................................................3 3.4 General Flow Routing .............................................. 4 3.5 Proposed Drainage Plan .............................................4 3.6 Hydrologic Analysis of the Proposed Drainage Conditions ................. 5 3.7 Allowable Street Flow Capacities ..................................... 7 3.8 Sidewalk Culvert Design ............................................ 7 3.9 Storm Sewer Design...............................................8 3.10 Swale Design.....................................................8 4. DETENTION...........................................................8 5. EROSION CONTROL ................................................... 9 5.1 Introduction......................................................9 5.2 General Description ................................................ 9 5.3 Soil Description................................................... 9 5.4 Erosion And Sediment Control Measures ............................... 9 5.5 Dust Abatement .................................................. 11 5.6 Tracking Mud on City Streets ....................................... 11 5.7 Maintenance.....................................................11 5.8 Permanent Stabilization ............................................ 11 6. MISCELLANEOUS.................................................... 12 6.1 Variances.......................................................12 6.2 Agreements.....................................................12 ' 7. REFERENCES........................................................13 ii 1 1 1 1 APPENDIX A - MAPS AND FIGURES APPENDIX B - HYDROLOGIC CALCULATIONS APPENDIX C - DRAINAGE STRUCTURE CALCULATIONS APPENDIX D - EROSION CONTROL CALCULATIONS APPENDIX E - DETENTION POND INFORMATION - OAKRIDGE BUSINESS PARK TENTH FILING iii I INTRODUCTION ' 1.1 Project Location Residence Inn @ Oakridge PUD Filing 25 is the development of a proposed hotel adjacent ' to Oak Ridge Drive, east of Lemay Avenue. This project is located in the Northwest One - Quarter of Section 6, Township 6 North, Range 68 West, of the Sixth Principal Meridian, in the City of Fort Collins, Larimer County, Colorado. (See FIGURE 1 - VICINITY MAP.) ' This project is bounded on the northeast by Oakridge Business Park, Tenth Filing, on the southwest by Oakridge Business Park, Thirteenth Filing, on the northwest by Oakridge ' Drive, and on the southeast by unplatted property. More specifically, this site can be found on Oakridge Drive just east of the intersection of Lemay Avenue and Oakridge Drive. 1.2 Site Characteristics ' The general topography of this site consists primarily of grassed area. An existing drainage swale crosses this site from the southwesterly to north central portion. (Said swale carries ' flows from Oakridge Business Park, Thirteenth Filing under an existing sidewalk chase and into an existing detention pond designed and constructed with Oakridge Business Park, ' Tenth Filing.) The slopes for this site range from 0.5 to 4 percent. t1.3 Soils The soils for this site are comprised of the Nunn clay loams (73). (See FIGURE 2 - SOIL ' MAP.) ' The Nunn clay loams complex consists of nearly level soils on high terraces and fans. Pertinent characteristics of this soil include slow runoff and a slight hazard of wind and water ' erosion. Nunn clay loams are categorized in Hydrologic Group C. ' The source for soil data is the "Soil Survey for Larimer County Area, Colorado', prepared by the United States Department of Agriculture Soil Conservation Service. 1 ' 1.4 Purpose and Scope of Report This report defines the proposed final drainage plan for Residence Inn @ Oakridge PUD ' Filing 25, including consideration of all on -site and tributary off. -site runoff. This report provides design calculations for all drainage facilities required for this development. 1.5 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. Runoff computations were prepared for the 2-year minor and 100-year ' major storm frequency utilizing 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. ' 1.6 Master Drainage Basin ' This site falls within the McClellands Drainage Basin. More specifically, is was included in the "Master Drainage Study for Oakridge Business Park," prepared by RBD Inc. ' Engineering Consultants in September 1990 (Oakridge Master Report). The Oakridge Master Report provided a storm drainage planning analysis for this portion of Oakridge, ' including outfall locations and flow quantities. (The Oakridge Master Report included information from the "Final Drainage Report for the Oakridge Business Park Tenth Filing," prepared by RBD Inc. Engineering Consultants in October 1987, in which the downstream detention ponds were sized.) ' 2. HISTORIC (EXISTING) DRAINAGE The historic flows for this site looked at with respect to the proposed development consist of the currently existing drainage patterns. In general, the existing drainage patterns for this 2 1 ' site consist of existing flows conveyed to the detention ponds designed and constructed as ' part of the development of the Oakridge Business Park, Tenth Filing (the upper detention #3 lower detention #4, designated pond and the pond as in the aforementioned Tenth Filing Drainage Report). Off -site flows are conveyed northeasterly from the Oakridge Business Park Thirteenth Filing ' through an existing grassed swale across the Residence Inn @ Oakridge PUD Filing 25 site and are outletted into the upper detention pond within the Tenth Filing. The on -site flows ' are conveyed northeasterly to the upper and lower detention ponds within the Tenth Filing. 3. DEVELOPED FLOWS ' 3.1 Method ' The Rational Method was used to determine both the 2-year and 100-year flows for the sub - basins indicated in this drainage report. A detailed description of the hydrologic analysis is provided in Section 3.6 of this report. ' The existing detention ponds designed and constructed with Oakridge Business Park Tenth Filing were sized to accommodate the developed flows from this site. Therefore, as no on - site detention is required, calculations have been provided for developed flows only. 3.2 Exterior Flows Exterior flows enter this site from the southwest and south. These exterior basins have been ' assigned basin labels of EX1-EX5. Proposed grading and drainage facilities will redirect the existing flows across this site to the existing detention ponds. ' 3.3 Onsite Flows ' Flows within this site will take the form of overlot, Swale, and pipe flow. These onsite basins have been assigned basin labels of A -I. All grading has been designed to carry flows ' away from structures to the proposed drainage facilities. 1 3 I 1 1 1 1 1 1 3.4 General Flow Routing The final drainage pattern for this area has been developed to carry flows to the proposed drainage facilities which outfall into the existing downstream detention ponds within Oakridge Business Park Tenth Filing. 3.5 Proposed Drainage Plan A qualitative summarization of the drainage patterns within each sub -basin and at each design point is provided in the following discussion paragraphs. Runoff from Subbasin EXl flows northwesterly from a high point in the proposed access drive to curb and gutter in Oakridge Drive. This flow is conveyed northeasterly, via curb and gutter, to an existing 5' Type `R' inlet in Oakridge Drive at the northwest comer of this site: Flow is then conveyed, via storm sewer, to the upper detention pond #3, as designated in the Oakridge Business Park Tenth Filing Drainage Report. Runoff from Subbasin EX2 is conveyed via sheet and gutter flow onto Subbasin B. Runoff from Subbasin EX3 (Oakridge Business Park Thirteenth Filing) is conveyed via concrete and grassed swales to a 24" storm sewer at Design Point 1. Runoff from Subbasin EX4 is conveyed via sheet flow to Design Point 1. Runoff from Subbasin EX5 is convey via sheet flow onto Subbasin E. Runoff from Subbasin A sheet flows to curb and gutter in Oakridge Drive where it is conveyed northeasterly to the afformentioned existing 5' inlet. Runoff from Subbasin B sheet flows over landscape and asphalt,and is then conveyed via concrete curb and gutter to a 4' curb inlet at Design Point 2. Runoff from Subbasin C is conveyed via roof drains and overland flow, including 4 1 I t 1 1 1 t 1 1 1 1 a swale/subdrain system, and then to an area inlet at Design Point 3. Runoff from Subbasin D is conveyed via roof drains and overland flow, including a swale/subdrain system, to an area inlet at Design Point 5. Runoff from Subbasin E is conveyed via roof drains, overland flow over landscape and asphalt areas, a swale/subdrain system, and curb and gutter to a 4' concrete sidewalk culvert at Design Point 7. Runoff from Subbasin F is conveyed via roof drains and overland flow into Swale "C" which flows to a 15" storm sewer at Design Point 8. Runoff from Subbasin G is conveyed via roof drains and overland flow onto Oakridge Business Park Tenth Filing, where it flows overland to the afformentioned upper detention pond #3, assigned Design Point 9. Runoff from Subbasins H sheet flows overland to the lower detention pond #4. The runoff from the combination of Subbasins EX2, EX3, EX4, B, C and D is conveyed as stated above into a 24" storm sewer system which discharges into Swale "A" and then into the afformentioned upper detention pond #3 at Design Point 9. The runoff from the combination of Subbasins EX5 and E is conveyed to Design Point 7 and then transported via a 4' concrete sidewalk culvert into Swale "C" within Subbasin F. The runoff from the combination of Subbasins EX5, E, and F are conveyed as stated above into Swale "C" which enters a 15" storm sewer at Design Point 8. This flow is then discharged into Swale "B" and then into upper detention pond #3. 3.6 Hydrologic Analysis of the Proposed Drainage Conditions The Rational Method was used to determine both 2-year and 100-year peak runoff values for 5 I 1 11 each Subbasin. Runoff coefficients were assigned utilizing Table 3-2 of the SDDCCS Manual. As stated above, the Rational Method was used for all hydrologic analyses for the project site. The Rational Method utilizes the SDDCCS equation: Q = CrCIA ,O. where Q is the flow 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. The frequency adjustment factor, Cf, is 1.0 for the initial 2-year storm and 1.25 for the major 100-year storm. The appropriate rainfall intensity information was developed based on rainfall intensity duration curves in the SDDCCS Manual. In order to utilize the rainfall intensity curves, the time of concentration is required. The following equation was used to determine the time of concentration: tC=t;+tc (2) where tc is the time of concentration in minutes, t is the initial or overland flow time in minutes, and t, is the travel time in the ditch, channel, or gutter in minutes. The initial or overland flow time is calculated with the SDDCCS Manual equation: t; = [1.87(1.1 - CCf)Lo.s[/(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 are attached in the Appendix of ' this report. Table 3.1 provides a summary of the design flows for all Subbasins and Design Points (DP's) associated with this site. 31 1 1 1 1 1 TA B,E D�2ATNA1� 5UMIKARX TABLE DESIGN AREA AREA C2 C100 Tc (2) Tc (100) Q (2) Q (100) POINT DESIG. (ACRES) (MIN) (MIN) (CFS) (CFS) EX1 0.016 0.95 1.00 5.0 10.0 0.05 0.1 2 EX2 0.041 0.95 1.00 5.0 10.0 0.12d8.0 1 EX3 1.630 0.60 0.75 12.3 12.1 2.26I EX4 2.040 0.57 0.71 16.0 10.0 2.387 EX5 0.279 0.57 0.71 10.8 10.0 0.39A 0.075 0.44 0.55 8.2 10.0 0.09 2 B 0.369 0.72 0.90 6.2 10.0 0.78 2.3 3 C 0.085 0.66 0.83 5.6 10.0 0.17 0.5 5 D 0.323 0.66 0.83 6.4 10.0 0.62 1.8 7 E 0.868 0.75 0.94 8.0 10.0 1.00.77 5.7 8 F 0.183 0.59 0.74 5.1 10.0 0.34 0.9 9 G 0.288 0.56 0.70 5.0 10.0 0.51 1.4 H 0.030 0.20 0.251 5.0 10.0 0.02 0.0 1 EX3,EX4 3.670 0.58 0.73 16.0 12.1 4.38 17.61 2 EX2,13 0.411 0.74 0.93 6.2 10.0 0.90 2.7 4 IEX3,EX4,C 3.755 0.59 0.74 16.5 12.4 4.43 17.8 5 EX3,EX4,C,D 4.077 0.59 0.74 16.7 12.5 4.83 19.5 6 EX2,EX3,EX4 B,C,D 4.488 0.60 0.75 17.0 12.7 5.39 21.8 7 EX5,E 1.147 0.70 0.88 10.8 10.0 1.96 7.1 8 EX5,E,F 1.329 0.69 0.86 13.2 11.7 2.05 7.63 EX I-EX5, A-G 3.7 Allowable Street Flow Capacities The Residence Inn @ Oakridge PUD Filing 25 does not impact flows on any existing or proposed streets. Therefore, calculations for allowable street capacities for the surrounding, existing streets are not included. 3.8 Sidewalk Culvert Design There are two locations within this site which require sidewalk culverts to be installed to convey flows. A 4' concrete sidewalk culvert at Design Point 7 conveys runoff into onsite 7 Swale "C". A second 4' concrete sidewalk culvert, along the path of Swale "A", conveys flows from the exit of the 24" storm sewer, under an existing sidewalk in the loth Filing, and then to upper detention pond #3. See Appendix C for design calculations. Storm Sewer Design Historically there is an existing grass swale crossing this site from Design Point 1 to the upper detention pond #3. A 24" storm sewer pipe is proposed to convey these flows in the developed condition from Design Point 1 to Swale "A". A second storm sewer system, 15" ADS, conveys flows from Swale "C" at Design Point 8 to Swale "B", which flows to upper detention pond #3. Included in Appendix C are hydraulic grade line calculations for each of these pipes. Swale Design Three design swales, Swale "A", "B", and "C" are proposed with this site development. Swale "A" begins at the downstream end of the proposed 24" storm sewer, and conveys flows to the upper detention pond #3. Swale "B" begins at the exit of the 15" storm sewer where it also flows to the upper detention pond #3. Swale "C" conveys flows from a 4' concrete sidewalk culvert at Design Point 7 to Design Point 8, the entrance to the 15" storm sewer. Appropriate design calculations have been included in Appendix C of this report and proposed cross sections have been provided on the grading and drainage plan. DETENTION As previously stated, the existing drainage patterns for this site consist of existing flows conveyed to the detention ponds designed and constructed as part of the development of the Oakridge Business Park, Tenth Filing (the upper detention pond #3 and the lower detention pond #4, as designated in the aforementioned Tenth Filing Drainage Report). The development of this site produces a "C" value of 0.674, which is greater than the "C" value of 0.57 shown in the Tenth Filing Drainage Report. However, as this increase is on an area of 2.16 acres of the overall area of 9.95 acres contributing to the existing upper pond, the overall impact of the increase in "C" value does not create the need for additional on -site ' or off -site detention. (Calculations are provided in the Appendix.) ' 5. EROSION CONTROL ' 5.1 Introduction ' This section represents the Erosion Control Report for the Residence Inn at Oakridge P.U.D., Filing No. 25, and was prepared to meet the regulatory requirements of the City of Fort Collins, Colorado. This report was prepared following the guidelines and regulations within the SDDCCS Manual. 5.2 General Description ' The total site is comprised of approximately 2.21 acres. The general topography of this site consists primarily of existing grassy vegetation with an existing swale crossing the site. The ' existing slopes range from I to 2 percent. ' 5.3 Soil Description ' In accordance with the Soil Conservation Service's (SCS) "Soil Survey of Fort Collins Area, Colorado" (copy reproduced in Appendix), the soils on -site consist of the following: ' Rainfall Wind Hydrologic Soil Designation Erodibility Zone Erodibility Zone Soil Group ' Nunn clay loam Slight Slight C (See Section 1.3 for further discussion of soils found on this site.) ' 5.4 Erosion And Sediment Control Measures ' Erosion and Sedimentation will be controlled from leaving the site by the use of straw bale 1 9 [1 ' barriers, inlet protection, construction entrance and silt fence. (See Appendix for Cost ' Estimate and the attached "Drainage and Erosion Control Plan" for details.) The measures are designed to limit the overall sediment yield increase due to construction ' as required by the City of Fort Collins. A construction schedule is contained in the Appendix which shows the overall time frame for construction activities. ' It is imperative that silt fence be installed prior to the commencement of any grading, ' including stripping. Silt fence should be installed along three edges of this site. Along Oakridge Drive silt fence will limit sediment transport to the street. Along the north property ' line silt fence will limit sediment transport to the existing upper detention pond #3. Along the east property line silt fence will limit sediment transport to the downhill unplatted property, where storm runoff enters the lower detention pond #4. All silt fence shall remain ' in place through the construction sequence and then until vegetation has been fully established on all disturbed areas. The gravel construction entrance shall be installed immediately after grading operations commence, and will reduce sediment transport to Oakridge Drive. It shall remain in place until paving operations are complete. ' Straw bale barriers are proposed for this site to reduce sediment transport within proposed onsite and offsite swales. They shall be installed along each swale immediately following ' grading operations which develop the swale. Straw bale barriers shall remain in place through the construction sequence and then until vegetation is fully established on all ' disturbed areas. Gravel inlet filters are proposed within this site at two area inlets, one curb inlet, and one } concrete sidewalk culvert. They should be installed immediately following the construction ' of each inlet. Another filter is proposed at an existing curb inlet in Oakridge Drive just north of this site. This filter should be installed prior to any grading operations. Each filter is proposed to reduced sediment transport into proposed and existing storm sewers which flow ' into upper detention pond #3. All filters should remain in place through the construction sequence and then until vegetation is fully established on all disturbed areas. ' 10 5.5 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, and to prevent dust which has originated from his operations from damaging crops, orchards, cultivated fields, and dwellings, or causing a 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. ' 5.6 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 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. 5.7 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 will require periodic replacement. Maintenance is the responsibility of the developer. 5.8 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. ' 11 6. MISCELLANEOUS 6.1 Variances There are no variances requested with the development of the Residence Inn @ Oakridge PUD Filing 25. 6.2 Maintenance Agreements The developer will be responsible for the maintenance of all temporary and permanent drainage structures. 12 7. REFERENCES 1. City of Fort Collins, "Storm Drainage Design Criteria and Construction Standards", (SDDCCS), dated May, 1984. 2. Urban Drainage and Flood Control District, "Urban Storm Drainage Criteria Manual", Volumes I and 2, dated March, 1969, and Volume 3 dated September, 1992. 3. "Master Drainage Study for the Oakridge Business Park", prepared by RBD Engineering Consultants, Inc., dated September, 1990. 4. "Final Drainage Report for the Oakridge Business Park Tenth Filing", prepared by RBD Engineering Consultants, Inc., dated October, 1987. 5. "Oakridge Business Park Thirteenth Filing Final Drainage Report", prepared by RBD Engineering Consultants, Inc., dated May, 1990. 6. "Final Drainage and Erosion Control for Oakridge Block One Fourth Filing", prepared by RBD Engineering Consultants, Inc., dated November, 1995. 13 I APPENDIX A ' MAPS AND FIGURES 1 1 1 [l 4 I' ,1 11 1 I a� WARREN LMR GOIl GOtJCK 1 : rP RLr hb rmp r Arm" rP LIPer � rw -- 1 ' MARMONT ROAD bP < 6r Q rb SITE 4 our by — rP rp a rh by r4 r4 FIGURE I -VICINITY MAP NTS JR Engineering, Ltd. I r Cis • � �4 1 , a I 1 [1 11 I 1 1 APPENDIX B HYDROLOGIC CALCULATIONS O) 0 ro w cr 0 0 w ' w O > a O N w O C9 = 2 W ' f J Q Z O ' Q0 F K CD N CD Z J LL O Ww Z O � O r- 'Y3 O N QJ J aoo U Z z U ' w W w o U H W U 0 d z 'L li w w 0 U) W O L 0 rn N V m J Fj Z } rn N O [D `D O Z Q w ' ca O r F W o U m N = O N Y J O O O w z z z r- w w w (D co (N U rw W to (D O n n N co (o U) O) co O N O J O O (D Lq U7 V n (D ID n VD N N co d j o 0 0 0 0 0 0 0 0 0 0 0 0 0 O U LL w zU. N N N N W N N N N N N j O O O O O O O O O O O w w Q O U o 0 O O N O O 0 Z Q O O O 0 O 0 0 0 0 0 S U LL O 1n N N LO D D Z W Q1 D) D) W DI O D) O (3) W O O O O O O O O O O O Y LL J O >?Q a O O O O O v O O O Q O O O 0 O O O O O O QO U. U. OW 0) m � m Z a)LO O 0 0 0 0 0 0 0 0 0 0 W (� O Z 0 0 o a co (n n co co Q 0 O O O O N (O fp Cl) O LLI J O O O O O ` O7 O Q' O O O O O O O O O O Q (� Q (D O O Qf (D D) Cl) co m c0 O n FJ lL v m (D O n N n O (O f7 co O N M CD CO OD co (h N N Q O O N O O O O O O O N O O o (D Z O r- Q m U 0 W lL 02 Q Q (Z') W W W W W w w 0 n rn Y (i 1 0 O n w z w n w n QZ_ 7 0 2 Z LL D O Y LL t lL � N A w D O Z Z o o 'v 0 Q i i 1 Z Q N ' LL fA 2 F O W U ' c Z U o z LL y LU ■ W O N Z J LL a w w 0 d ' J � � z z O m w W U w ' o Z Z o U w It z � � Z C to W W } (If N LL ' 0 U O 0 w O A N (n O } Z } c n O m O ca � Q W �z� ow Q O a ' m O w 0 D J 0 U to N N K w w It 13 Q t- F w Z Z 2 2 Z Z w w Z_ Z_ N N O O lh O tp N N co V O O O J LL'l i0 � to O O tp N tp aD u') h h Z u v LL �- Z O O O O N O O t0 C th E m� o 2 Y N to o o to o to N o O 0 0 t0 0 Ci J N N N N N M N x Q N N U at u 7 W t0 N N tp V. O 7 N N (1 16 t") O td w to tp aD to N V E u 0 U V N N C9 N fp N N N 7 � o E t0 N to h n N N N d W O th tp to O N N O O O O O O O e a0 w H � M V � t00 QOi fOp � C C n M a0o N N J ... N H � V c0 V N r to N N N E cp O Y O O N N N to O O N N N tV N _ e N 05 to Y o n o rn t0 C� to m t0 a 0 v 0 n o v to V o S v J W > O n rn h rn o m r o n to v a N r ro m co o In n rn t0 co tp 0 N ^ o 0 0 0 00 0 0 0 0 0 0 0 Q w U in F � z F to 0 o rn to to to co o 0 r> m o y N 0 0 N 0 O G O O O O O O Q Z F- U Z CO O N r N th O n t0 O w a 0 z N Z m w w w w 0¢ 7 Q m w h O m x i O T O) 0 r I 1 Z 2 N � ' h 0 W o � Z z U o Z LL F o to W a 1C1 N (7 Z J LL O a 1 w 0 Ix Y Opp ' 0 Z Z Z W W Z O 0oZ w Q 0 ❑ >- Z '6 x O U W O !n LL 0 O W O Q1 N ci n p m a�i o O Z U Q W ca Z Dui <aag 'W 0 U w O Z) �N ❑Urn I N 0 0 0 0 0 0 0 0 0 0 0 II II w w II II II II II II II II It O O > W Z Z Z Z_ W W Z Z Z Z_ Z_ Z Z Z Z 0 0 0 0 0 0 0 0 0 0 0 0 J O O N O O O O O O O O O O Z u v LL + h V t0 YI N r O c7 .- O N O O Z pOp C m V E m ly w Y W N In o N o In o In N o O 0 0 l0 V 0 U Z J N N N N M N = In N N In u 7 V CD t7 N eD O m O O) O O. t'f N ED r t7 < Y IA V V E u 0 U V V V N N C9 N t0 L C O E t0 17N t0 17 17 770 r N N N d � t0 C) t0 t0 10 h N O O O O O O e � � v w c E wj J J Z rn eo n eo <0 17 U0 rn O _ C `E `D O O O O h O O t0 O O O N N N N N 10 O N _ N O e v or rn can m a v or v a O C c a QZ W > O O o O o In r I� n N l0 O rn N o N o M m V r O r h N O O O O O O Q U W H m i F fp a O cn O v O r 10 r m c0 IO 0� M N O co th co � m O m O O t0 O N O th O C7 N N O ym N O O N O O O O O O O O O Q Z F. (7 Z (n O N r N to h r c0 O w o. ❑ Z (A Z X X Q co U ❑ W m' F Q m W Wiwx W � N I I I I I m fIX k( - e \ >Owww \ ix } i .. $z§)§w o 0 w 0 § } ' m rn 1 2 W � N K ' W C1 O W N a y O w O ' S W = g J O Z f o ' O C N Z J LL D y a N W ' m a 0 C1 CI � a � m `o Y OJ U Z U lHf > w o W 9U U 0 'Cowl): } Z LL N { W K K b T LL N N rnd O m o Z Q W c W < a W N p W o i�ii i � i its I APPENDIX C DRAINAGE STRUCTURE CALCULATIONS 11 1 1 1 1 1 JIB, Engineering, Ltd. PROJECT Qe5�lPrre inn SUBJECT TA! e+ ffie E� CLIENT C-tl Pr-/ r, BY FSW CHECK BY JOB NO. DATE SHEET NO. % OF f j7- z ([ Li f p111 0 z , a , L iIi 1 t _.,.._.... E _. e-FS ocflp x j j V - Pp�i 4-v<1SPE-CI FTC Qn ..ear:ee j J _j..__Po.�rig__ aepk.. r o.s L: /FTz.W` ...a... �.... f Z D wm.... m..w e.e....u.-.^..- .. _...�.......�+«.v...._»._.w..n.mw....ma..n«m....�.............v...... < �,23 'ens ...vv...s-.-v....._..�. IL f f , A � o�P.. raj �a e �, ► . , E j __ 1 Q f .51K 5 f All t E E_ t � _ 1• g V ;ty I.0 12 5 ' 10 4 .9 II g 3 10 6 g w 0 u- 2 9 4 IL H � tL ' 7 a 3 — g w z 1.5 a c 6 7 Pot` mp�ey � t z I.0 Ei 1•L c� _ I.0 z 9 e_Parf a_ _ z J W 5.5 0 ----- 6 o ' U. w W z o .7 .4 5 z z .4 = w 6 z 4.5 z ao .3 W 2 4 v = 2 0 .5 CD z z E- c� o w '3 3.5 W w T .4 a- J ow 0 .08 0 0 ' .25 3 0 .06 3 x x 0 cD ww z w w o: .04 x .25 ' 2.5 W w 2 a- .03 a ' .02 0 2 a a 2 U � a ' .15 .01 0 .15 L U. 0 ' o — — Yo a ' „ a=2 h .10 ' .I 1.2 Figure 5-2 ' NOMOGRPAH FOR CAPACITY OF CURB OPENING INLETS IN SUMPS, DEPRESSION DEPTH 2" Adapted from Bureau of Public Roads Nomograph ' MAY 1984 5-10 DESIGN CRITERIA Ar�t� rN Ctrs U �P 3$ U P S 1 1 MAY 1984 0.8 0.7 w 0.6 w EXAMPLE Z 0.5 Cr w > 0.4 O 2 a 0.3 w 0 z 0.2 o z 0 a 0.1 0.0 1 0 1 2 3 3• 4 FLOW INTO INLET PER SO. FT. OF OPEN AREA (CFS/FT2) Figure 5-3 CAPACITY OF GRATED INLET IN SUMP (From: Wright -McLaughlin Engineers, 1969) 5-11 DESIGN CRITERIA [] 1 1 1 1 1 ------------------ Beginning Calculation Discharge: 17.68 cfs at node I-1 Discharge: 0.50 cfs at node I-4 Discharge: 17.97 cfs at node J-1 Discharge: 19.66 cfs at node I-2 Discharge: 2.74 cfs at node I-3 Discharge: 22.05 cfs at node J-2 Discharge: 21.95 cfs at node Outlet Beginning iteration 1 Discharge: 17.68 cfs at node I-1 Discharge: 0.50 cfs at node I-4 Discharge: 17.94 cfs at node J-1 Discharge: 19.60 cfs at node I-2 Discharge: 2.74 cfs at node I-3 Discharge: 21.96 cfs at node J-2 Discharge: 21.86 cfs at node Outlet Completed iteration 1 Cycle------------------- Current discharge convergence relative error Target discharge convergence relative error: Beginning iteration 2 0.41213878e-2 0.001 Discharge: 17.68 cfs at node I-1 Discharge: 0.50 cfs at node I-4 Discharge: 17.94 cfs at node J-1 Discharge: 19.60 cfs at node I-2 Discharge: 2.74 cfs at node I-3 Discharge: 21.96 cfs at node J-2 Discharge: 21.86 cfs at node Outlet Discharge Convergence Achieved in 2 iterations: relative error: 0 ** Warning: Design constraints not met. Violation: P-6 does not meet minimum velocity constraint. --------------------- Calculations Complete ---------------------- ** Analysis Options ** Friction method: Manning's Formula HGL Convergence Test: 0.001000 Maximum Network Traversals: 5 Number of Pipe Profile Steps: 5 Discharge Convergence Test: 0.001000 Maximum Design Passes: 3 66076384e-4 ' ----------------- Network Quick View ------------------------ I Hydraulic Grade I Length I Size I Discharge I Upstream I Downstream 'Label P-1 117.00 24 inch 17.68 77.01 76.30 P-2 53.00 24 inch 17.94 75.93 75.77 P-3 66.00 24 inch 19.60 75.45 75.08 'P-4 62.00 24 inch 21.96 74.51 73.80 P-5 15.00 15 inch 2.74 75.10 75.08 P-6 50.00 8 inch 0.50 76.34 76.30 ' 1----------- Elevations ---------------- Label I Discharge I Ground I Upstream HGL I Downstream HGL I I-1 17.68 77.49 77.01 77.01 J-1 17.94 78.11 76.30 75.93 I-2 19.60 76.80 75.77 75.45 J-2 21.96 77.25 75.08 74.51 21.86 74.10 73.80 73.80 'Outlet I-3 2.74 76.46 75.10 75.10 Project Title: RESIDENCE INN - OAKRIDGE BUSINESS PARK 25TH Project Engineer: JR ENGINEERING, LTD. xA911700U117st3.slm JR ENGINEERING, LTD StorrnCAD 0.0 10/24/97 04:07:11 PM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 2 ' I-4 0.50 77.30 76.34 76.34 Elapsed: 0 minute(s) 4 second(s) 11 1 [1 Project Title: RESIDENCE INN - OAKRIDGE BUSINESS PARK 25TH Project Engineer: JR ENGINEERING, LTD. x:\911700\9117st3.stm JR ENGINEERING, LTD Storm CAD v1.0 t10/24/97 04:07:11 PM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 2 of 2 `l CuQf3IE7 ' zW"F6S rH Sr1 73.9$ � a P-5 ` 1-1 P-1 J-1 P-23 �y3z y IV I-2 -3 _ J-2 zy''RCp �s WZz 7- "A 73.toO Z4"AAs 7z.8y Zoo iN= 75.41 h 7iH47 �P-4 Q P-6 Aa��sN�cr // r o - � ' 7590 1-4 <<: •5) �`^ �r j g0S Outlet _ to 7 IZ /42ER Sn�l-ET 1 Project Title: RESIDENCE INN - OAKRIDGE BUSINESS PARK 25TH Project Engineer: JR ENGINEERING, LTD. 'x:\911700\9117st3.stm JR ENGINEERING, LTD Storm CAD v1.0 09/08/97 07:09:49 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 11 ------------------ Beginning Calculation Cycle ------------------- Discharge: 7.63 cfs at node I-1 Discharge: 7.63 cfs at node J-1 Discharge: 7.63 cfs at node Outlet Beginning iteration 1 Discharge: 7.63 cfs at node I-1 Discharge: 7.63 cfs at node J-1 Discharge: 7.63 cfs at node Outlet Discharge Convergence Achieved in 1 iterations: relative error: 0.0 Warning: No Duration data exists in IDF Table Information: Outlet Known flow propogated from upstream junctions. Information: P-2 Surcharged condition Information: J-1 Known flow propogated from upstream junctions. --------------------- Calculations Complete ---------------------- ** Analysis Options ** 'Friction method: Manning's Formula HGL Convergence Test: 0.001000 Maximum Network Traversals: 5 Number of Pipe Profile Steps: 5 'Discharge Convergence Test: 0.001000 Maximum Design Passes: 3 '----------------- Network Quick View ------------------------ ' I Hydraulic Grade I Label I Length I Size I Discharge I Upstream I Downstream I 2-1 50.00 15 inch 7.63 75.09 74.51 P-2 19.00 15 inch 7.63 74.03 73.80 1 Label I I Discharge I I-1 7.63 J-1 7.63 Outlet 7.63 Elapsed: 0 minute(s) 0 Ground 75.86 75.60 73.10 second(s) Elevations ---------------- I Upstream HGL I Downstream HGL I 75.09 75.09 74.51 74.03 73.80 73.80 Project Title: RESIDENCE INN - OAKRIDGE BUSINESS PARK 25TH Project Engineer: JR ENGINEERING, LTD. x:%911700W117st4.stnn JR ENGINEERING, LTD Storm CAD v1.0 10/24/97 04:06:09 PM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 ' -7 Outlet !S FES 1 P-2 J _ 1 Nt h - sT 3 7Z �o P-1 I � ' JS" FES 1 Project Title: RESIDENCE INN - OAKRIDGE BUSINESS PARK 25TH Project Engineer: JR ENGINEERING, LTD. x:\911700\9117st4.stm JR ENGINEERING, LTD StormCAD v1.0 09/08/97 11:04:59 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 d 1 1 SIDEWALK CULVERT AT DP7 -133% Q100 Worksheet for Rectangular Channel Project Description Project File x:\911700\9117dr.fm2 Worksheet SIDEWALK CULVERT AT DP7 Flow Element Rectangular Channel Method Manning's Formula Solve For Channel Depth Input Data Mannings Coefficient 0.013 Channel Slope 1.000000 % Bottom Width 4.00 ft Discharge 9.54 ft/s ' Results Depth 0.42 ft Flow Area 1.69 ft2 ' Wetted Perimeter 4.84 ft Top Width 4.00 ft Critical Depth 0.56 ft Critical Slope 0.004152 ft/ft ' Velocity 5.66 ft/s Velocity Head 0.50 ft Specific Energy 0.92 ft ' Froude Number 1.54 Flow is supercritical. 'Sep 10, 1997 JR Engineering, Ltd. FlowMaster v4.1b 01:54:07 Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 I SWALE "A" 24" ADS TO DP9(POND) Worksheet for Irregular Channel Project Description Project File x:\911700\9117dr.fm2 Worksheet SWALE "A" TO POND -CONCRETE PAN AND COBS Flow Element Irregular Channel Method Manning's Formula Solve For Water Elevation Input Data ' Channel Slope 1.000000 % Elevation range: 100.00 ft to 101.60 ft. ' Station (ft) 0.00 Elevation (ft) 101.60 Start Station 0.00 6.00 100.10 6.00 7.00 100.10 7.00 ' 7.75 100.00 8.50 8.50 100.10 9.50 9.50 100.10 15.50 101.60 Discharge 29.00 ft'/s ' Results Wtd. Mannings Coefficient 0.026 Water Surface Elevation 101.05 ft ' Flow Area 6.97 ft2 Wetted Perimeter 11.32 ft Top Width 11.07 ft ' Depth 1.05 ft Critical Water Elev. 101.01 ft Critical Slope 0.011594 ft/ft Velocity 4.16 ft/s Velocity Head 0.27 ft Specific Energy 101.32 ft ' Froude Number 0.92 Full Flow Capacity 68.02 ft'/s Flow is subcritical. ' 11 End Station 6.00 7.00 8.50 9.50 15.50 Roughness 0.060 0.040 0.013 0.040 0.060 'Sep 10, 1997 JR Engineering, Ltd. FlowMaster v4.1b 01:37:35 Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 11 1 I 1 1 t SWALE "A" CROSS SECTION Cross Section for Irregular Channel Project Description Project File x:\911700\9117dr.fm2 Worksheet SWALE "A" TO POND -CONCRETE PAN AND COBS Flow Element Irregular Channel Method Manning's Formula Solve For Water Elevation Section Data Wtd. Mannings Coefficient 0.026 Channel Slope 1.000000 % Water Surface Elevation 101.05 ft Discharge 29.00 fN/s 1 1 1 1 1 1 1 1 1 1 1 1 I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1------- 1 1 1 1 1 1 I 1 1 1 1 1 I 1 1 1 I 1 1 1 I 1 I 1 1 101.2 1 -------I-------- --------r-------- r--------r-------1 ----------------t I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 I 1 1 1 1 1 I I I 1 1 1 1 1 I I 101.0 I I 1 --------I- 1 I = I 1 1 I I I 1 I 1 1 1 I 1 I 1 I 1 1 I I 1 I I I I I 1 I 1 I 1 I I 1 1 I 1 C I 1 I I 1 I I 1 100.p y O - I 1 ------- ---- _ -------- I_ ------- 1 --------1 --------1 - ------ I --------- I ' I 1 I I I I I I I 1 I I 1 I 1 I tV W I 1 I I I I 1 1 I 1 I I I I 1 1 100.6 --------;---------------- --------- ;-------- ;------ --;---------------- I I I I 1 I I 1 1 1 I 1 1 1 1 1 1 1 I 1 1 I 1 1 100.4 1 1 I I 1 I I 1 1 1 I I I 1 I 1 --------1----------------1----------------'---------------- '--------' 1 1 I 1 I I 1 1 I I I 1 I I I I 1 I I 1 I 1 I 1 100.2 I- I I I 1 1 I I --------'-------- ------- ---------L--------------- J,--------'-------- 1 I i I 1 I 1 1 1 I I I 1 I 1 1 I I I 1 1 1 1 1 1 1 I 1 I 1 1 100.0 ' 0.0 2.6 4.0 6.0 8.0 10.0 12.0 Station (ft) 14.0 16.0 'Sep 10, 1997 JR Engineering, Ltd. 01:37:55 Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 FlowMaster v4.1b Page 1 of 1 ' SWALE "B" 15" ADS TO DP9(POND) Worksheet for Irregular Channel ' Project Description Project File x:\911700\9117dr.fm2 Worksheet SWALE "B" TO POND -CONCRETE PAN AND COBS ' Flow Element Irregular Channel Method Manning's Formula Solve For Water Elevation ' Input Data Channel Slope 1.400000 % Elevation range: 100.00 ft to 101.60 ft. ' Station (ft) 0.00 Elevation (ft) 101.60 Start Station 0.00 End Station 6.00 Roughness 0.060 6.00 100.10 6.00 7.00 0.040 7.00 100.10 7.00 8.50 0.013 ' 7.75 100.00 8.50 9.50 0.040 8.50 100.10 9.50 15.50 0.060 9.50 100.10 ' 15.50 101.60 Discharge 10.15 fe/s ' Results Wtd. Mannings Coefficient 0.022 Water Surface Elevation 100.57 ft ' Flow Area 2.58 ftZ Wetted Perimeter 7.37 ft Top Width 7.24 ft ' Depth 0.57 ft Critical Water Elev. 100.61 ft Critical Slope 0.010525 ft/ft Velocity 3.93 ft/s Velocity Head 0.24 ft Specific Energy Froude Number 100.81 1.16 ft Full Flow Capacity 80.48 ft /s Flow is supercritical. 1 1 1 Sep 10, 1997 JR Engineering, Ltd. FlowMaster v4.1b 02:21:14 Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 I 1 1 1 1 L SWALE "B" CROSS SECTION Cross Section for Irregular Channel Project Description Project File x:\911700\9117dr.fm2 Worksheet SWALE "B" TO POND -CONCRETE PAN AND COBS Flow Element Irregular Channel Method Manning's Formula Solve For Water Elevation Section Data Wtd. Mannings Coefficient 0.022 Channel Slope 1.400000 % Water Surface Elevation 100.57 ft Discharge 10.15 ft/s 101.4 101.2 101.0 c 0 100.8 m N W 100.6 100.4 100.2 100.0' v ' 0.0 2.0 4.0 6.0 8.0 10.0 Station (ft) 12.0 14.0 16.0 Sep 10, 1997 JR Engineering, Ltd. FlowMaster v4.1b 02:21:27 Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 Project Description Project File x:\911700\9117dr.fm2 Worksheet T SWALE DP7 TO DP8 ' Flow Element Trapezoidal Channel Method Manning's Formula ' Solve For Channel Depth Input Data ' Mannings Coefficient 0.060 Channel Slope 1.200000 % Left Side Slope 4,00 H : V ' Right Side Slope 4.00 H : V Bottom Width 3.00 ft Discharge 10.15 fN/s Results ' Depth 0.86 ft Flow Area 5.57 ft' Wetted Perimeter 10.12 ft ' Top Width 9.91 ft Critical Depth 0.55 ft Critical Slope 0.073712 ft/ft Velocity 1.82 ft/s ' Velocity Head 0.05 ft Specific Energy 0.91 ft Froude Number 0.43 Flow is subcritical. 1 'Sep 10, 1997 01:39:59 SWALE "C" DP7 TO DP8 Works heet for Trapezoidal Channel JR Engineering, Ltd. FlowMaster v4.1b Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 JREngineering, Ltd. CLIENT e r;t3 JOB NO. S �j097. o PROJECT Uc��� ic�ye Q,P, Y -ZS BY I-W CHECK BY___ DATE /D f2y 97 SUBJECT Low caes o c lLpArCA;yj SWdIeS SHEET NO. _ OF } a f e.� rT�oo._.C,�o st � �.�._p� ..__. r (� c d.��.._ dl�j��� Et ._see}�o . �t'^Gq o��rlvOuiEn oar` lam (T s Sec�Elo..., s C40,411� C✓,i•cgL _.-up dpy 10� � 40�� i hE5 swo�C. t i ! � r F E LA D f>tAaF i3So S F C . io 4 , (6l2r��e 3u?o19i3Vt, T s so 90 o T 1 133 des U dew ! r �hOw� C to l i (oz'oo s F" C- 9 Re o, 24 ,cioo}( S)fi Zpp q � o � zoot zr.So E �tb a � z , j 'i? o i- LzI,z) i o CF s .,t-F-S ,. . .__7.0 C� F 1 SUBDRAIN SWALE "D" Worksheet for Irregular Channel Project Description Project File x:\911700\9117dr.fm2 Worksheet SUBDRAIN SWALE "D" Flow Element Irregular Channel Method Manning's Formula Solve For Water Elevation Input Data ' Channel Slope 0.500000 % Elevation range: 77.20 ft to 77.50 ft. Station (ft) Elevation (ft) Start Station ' 0.00 77.50 0.00 5.55 77.20 5.55 7.05 77.20 7.05 13.30 77.50 ' Discharge 1.20 fN/s 11 Results Wtd. Mannings Coefficient 0.047 Water Surface Elevation 77.47 ft Flow Area 1.88 ft2 Wetted Perimeter 12.26 ft Top Width 12.25 ft Depth 0.27 ft Critical Water Elev. 77.35 ft Critical Slope 0.059980 ft/ft Velocity 0.64 ft/s Velocity Head 0.01 ft Specific Energy 77.48 ft Froude Number 0.29 Full Flow Capacity 1.48 ft'/s Flow is subcritical. End Station 5.55 7.05 13.30 Roughness 0.060 0.035 0.060 Oct 24, 1997 JR Engineering, Ltd. FlowMaster v4.1b 08:51:46 Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 I SUBDRAIN SWALE "E" Worksheet for Irregular Channel Project Description Project File x:\911700\9117dr.fm2 Worksheet SUBDRAIN SWALE "E" Flow Element Irregular Channel Method Manning's Formula Solve For Water Elevation Input Data Channel Slope 0.500000 % Elevation range: 77.25 ft to 77.80 ft. Station (ft) Elevation (ft) Start Station 0.00 77.80 0.00 ' 5.25 77.25 5.25 6.75 77.25 6.75 12.00 77.80 ' Discharge 2.00 ft/s tResults Wtd. Mannings Coefficient 0.045 Water Surface Elevation Flow Area 77.66 2.23 ft ft' Wetted Perimeter 9.38 ft ' Top Width Depth 9.34 0.41 ft ft Critical Water Elev. 77.49 ft Critical Slope 0.047039 ft/ft ' Velocity 0.90 ft/s Velocity Head 0.01 ft Specific Energy 77.67 ft Froude Number 0.32 Full Flow Capacity 3.79 ft3/s Flow is subcritical. 1 End Station 5.25 6.75 12.00 Roughness 0.060 0.035 0.060 Oct 24, 1997 JR Engineering, Ltd. FlowMaster v4.1b ' 09:19:01 Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 [1 .1 APPENDIX D EROSION CONTROL CALCULATIONS [1 11 [1 1 1 RAINFALL PERFORMANCE STANDARD EVALUATION STANDARD FORM A 1] r-- iL ,I 1 I� 1 PROJECT: RESIDENCE INN AT OAKRIDGE P.U.D. FILING 25 COMPLETED BY: FSW DATE: 09/09/97 DEVELOPED ERODIBILITY Asb Lsb Ssb Lb Sb PS SUBBASIN ZONE (AC) (FT) (%) (FT) EXI 0.016 275 0.8 EX2 0.041 250 1.2 A 0.075 265 0.8 B 0.369 210 1.2 C 0.085 125 1.0 D 0.323 190 0.8 E 0.868 360 0.7 F 0.183 200 2.0 G 0.288 45 20.0 H 0.030 10 2.0 2.278 1 1 1 239.8 1 3.4 1 82.0 PS is taken from Table 8-a (Table 5.1, Erosion Control Reference Manual) by interpolation. 1 Therefore, an Erosion Control Plan will be developed to contain 82.0 % of the rainfall sedi- mentation that would normally flow off a bare ground site during a 10-year, or less, precipitation event. 1 1 1 r-. I 1 1 1 (970)491-9888 [l I JR Engineering, Ltd. 2620 E. Prospect Rd., Ste. 190, Fort Collins, Colorado 80525 EFFECTIVENESS CALCULATIONS PROJECT: RESIDENCE INN AT OAKRIDGE P.U.D. FLING 25 STANDARD FORM B COMPLETED BY: FSW DATE: 09/09/97 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 SILT FENCE 1.00 0.50 STRAW MULCH 0.06 1.00 ESTABLISHED GRASS 0.08 1.00 HOUSE/DRIVE 0.01 1.00 MAJOR PS EROSION CONTROL SUB AREA BASIN N DEVICES BASIN (Ac) CALCULATIONS AC 82.0 EXI 0.02 SILT FENCE 0.00 HOUSE/DRIVE 0.00 ROADSIWALKS 0.02 STRAWIMULCH 0.00 WEIGHTED C-FACTOR 0.01 WEIGHTED P-FACTOR 0.50 EFF 99.50 EX2 0.04 SILT FENCE 0.00 HOUSE/DRI V E 0.00 ROADS/WALKS 0.04 STRAW/MULCH 0.00 WEIGHTED C-FACTOR 0.01 WEIGHTED P-FACTOR 0.50 EFF 99.50 SILT FENCE A 0.08 SILT FENCE 100% HOUSE/DRIVE 0.00 ROADS/WALKS 0.02 STRAWIMULCH 0.05 WEIGHTED C-FACTOR 0.04 WEIGHTED P-FACTOR 0.50 EFF 97.80 GRAVEL INLET FILTER B 0.37 SILT FENCE 0.00 HOUSE/DRIVE 0.00 ROADS/WALKS 0.25 STRAW/MULCH 0.12 WEIGHTED C-FACTOR 0.03 WEIGHTED P-FACTOR 0.80 EFF 97.95 ' X:\911700\QPMEFFECT1.WB2 PAGE 1 OF 3 1 1 1 1 JR Engineering, Ltd. (970)491-9888 2620 E. Prospect Rd., Ste. 190, Fort Collins, Colorado 80525 EFFF.CfIVF.NFCC CA1.(1TF.AT1(1NC PROJECT: RESIDENCE INN AT OAKRIDGE P.U.D. FILING 25 STANDARD FORM B COMPLETED BY: FSW DATE: 09/09/97 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 SILT FENCE 1.00 0.50 STRAW MULCH 0.06 1.00 ESTABLISHED GRASS 0.08 1.00 HOUSEIDRI VE 0.01 1.00 MAJOR PS EROSION CONTROL SUB AREA BASIN N DEVICES BASIN (Ac) CALCULATIONS AC GRAVEL INLET FILTER C 0.09 SILT FENCE 0.00 HOUSE/DRIVE 0.03 ROADS/WALKS 0.03 STRAWIMULCH 0.03 WEIGHTED C-FACTOR 0.03 WEIGHTED P-FACTOR 0.80 EFF 97.60 GRAVEL INLET FILTER D 0.32 SILT FENCE 0.00 HOUSE/DRIVE 0.13 ROADSIWALKS 0.07 STRAW/MULCH 0.13 WEIGHTED C-FACTOR 0.03 WEIGHTED P-FACTOR 0.80 EFF 97.64 GRAVEL INLET FILTER E 0.87 SILT FENCE 0.00 HOUSE/DRI V E 0.17 ROADS/WALKS 0.46 STRAW/MULCH 0.24 WEIGHTED C-FACTOR 0.02 WEIGHTED P-FACTOR 0.80 EFF 98.11 STRAW BALE DIKES F 0.18 SILT FENCE 0.00 HOUSE/DRIVE 0.07 ROADS/WALKS 0.03 STRAW/MULCH 0.09 WEIGHTED C-FACTOR 0.03 WEIGHTED P-FACTOR 0.80 EFF 97.30 ' X:\911700\QPW\EFFECTI.WB2 PAGE 2 OF 3 1 1 1 1 1 1 1 JR Engineering, Ltd. 2620 E. Prospect Rd., Ste. 190, Fort Collins, Colorado 80525 EFFECTIVENESS CAI1-1 ILATIONC (970)491-9888 PROJECT: RESIDENCE INN AT OAKRIDGE P.U.D. FILING 25 STANDARD FORM B COMPLETED BY: FSW DATE: 09/09/97 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 SILT FENCE 1.00 0.50 STRAW MULCH 0.06 1.00 ESTABLISHED GRASS 0.08 1.00 HOUSE/DRIVE 0.01 1.00 MAJOR PS EROSION CONTROL SUB AREA BASIN (%) DEVICES BASIN (Ac) CALCULATIONS AC SILT FENCE G 0.29 SILT FENCE 1000/0 HOUSE/DRI V E 0.14 ROADS/WALKS 0.00 STRAW/MULCH 0.15 WEIGHTED C-FACTOR 0.01 WEIGHTED P-FACTOR 0.50 EFF 99.74 SILT FENCE H 0.03 SILT FENCE 100% HOUSE/DRIVE 0.00 ROADS/WALKS 0.00 STRAW/MULCH 0.03 WEIGHTED C-FACTOR 0.06 WEIGHTED P-FACTOR 0.50 EFF 97.00 OVERALL EFFECTIVENESS = 98.15 > 82.0, O.K. X:\911700\QPMEFFECTI.WB2 PAGE 3 OF 3 1 1 1 1 1 1 1 1 1 1 1 JR Engineering, Ltd. 2620 E. Prospect Rd., Ste. 190, Fort Collins, CO 80525 (970)491-9888 10/24/97 CONSTRUCTION SEQUENCE STANDARD FORM C PROJECT: OAKRIDGE BUSINESS PARK FILING NO. 25 - RESIDENCE INN SEQUENCE FOR 1997 ONLY COMPLETED BY: FSW DATE: 10/24/97 Indicate by use of a bar line or symbols when erosion control measures will be installed. Major modifications to an approved schedule may require submitting a new schedule for approval by the City Engineer. MONTH SEP. OCT. NOV. DEC. JAN. FEB. MAR. APRIL MAY Demolition Grading Wind Erosion Control: Soil Roughing Perimeter Barrier Additional Barriers Vegetative Methods Soil Sealant Other Rainfall Erosion Control Structural: Sediment Trap/Basin Inlet Filters Straw Barriers Silt Fence Barriers Sand Bags Bare Soil Preparation Contour Furrows Terracing Asphalt/Concrete Paving Other Vegetative: Permanent Seed Planting Mulching/Sealant Temporary Seed Planting Sod Installation Nettings/Mats/Blankets Other BLDG. CONSTRUCTION STRUCTURES: INSTALLED BY: CONTRACTOR MAINTAINED BY: DEVELOPER VEGETATION/MULCHING CONTRACTOR: TO BE DETERMINED BY BID DATE SUBMITTED: 10/97 APPROVED BY CITY OF FORT COLLINS ON: HDI/SF-C:89 X:\911700\QPVMCONSTSEQ.WB2 PAGE 1 OF 1 ' JR Engineering, Ltd. (970) 491-9888 2620 E. Prospect Rd., Ste. 190, Fort Collins, Colorado 80525 09/09/97 1 1 1 1 1 1 RESIDENCE INN AT OAKRIDGE P.U.D. FILING 25 JOB NO. 9097.01 EROSION CONTROL COST ESTIMATE COMPLETED BY: FSW ITEM DESCRIPTION UNITS I UNIT COST I QUANTITY I TOTAL COST 1 SILT FENCE LF $2.50 840 $2,100.00 2 INLET PROTECTION EACH $250.00 5 $1,250.00 3 STRAW BALE BARRIER LF $5.00 100 $500.00 4 CONSTRUCTION ENTRANCE EACH $250.00 1 $250.00 PRELIMINARY COST $4,100.00 TOTAL COST WITH FACTOR OF 150% $6,150.00 CITY RFRFFr)rNC. rO4ZT ITEM DESCRIPTION UNITS I UNIT COST QUANTITY ITOTAL COST 1 I RESEED/MULCH ACRE $1,300.00 1 2.60 1 $3,380.00 PRELIMINARY COST $3,380.00 TOTAL COST WITH FACTOR OF 150% $5.070.00 X:\911700\QPW\EROSCOST.WB2 PAGE 1 of 1 ESCROW AMOUNT = $6,150.00 I 11 1 11 1 APPENDIX E DETENTION POND INFORMATION - OAKRIDGE BUSINESS PARK TENTH FILING 1 1 1 1 1 UPPER DETENTION POND ORIGINAL CALCULATIONS Project Name: Residence Inn - Oakridge 25th Project No.: 9097.01 By: FS W Checked By: Date: 4/24/97 SOUTHEAST DETENTION POND (BASIN A) Site Area = 9.95 ac Allowable Composite "C" 0.821 Developed Composite "C" 0.657 Developed Site Tc 10 min Allowable release 1.99 TIME (min) 1 (in/hr) DEVELOPED NET ALLOWABLE RELEASED DELTA DELTA VOLUME (co RELEASE (cfs) VOLUME (cf) VOLUME (cf) VOLUME (ac-ft 5 9.40 23043 1.99 597 22446 0.515 10 7.29 35742 1.99 1194 34548 0.793 15 6.16 45302 1.99 1791 43511 0.999 20 5.20 50990 1.99 2388 48602 1.116 25 4.60 56383 1.99 2985 53398 1.226 30 4.17 61335 1.99 3582 57753 1.326 35 3.80 65208 1.99 4179 61029 1.401 40 3.50 68640 1.99 4776 63864 1.466 45 3.25 71704 1.99 5373 66331 1.523 50 3.00 73543 1.99 5970 67573 1.551 55 2.80 75504 1.99 6567 68937 1.583 60 2.60 76485 1.99 7164 69321 1.591 70 2.30 78936 1.99 8358 70578 1.620 80 2.05 80407 1.99 9552 70855 1.627 90 1.88 82956 1.99 10746 72210 1.658 100 1.70 83349 1.99 11940 71409 1.639 110 1.56 84133 1.99 13134 70999 1.630 120 1.43 84133 1.99 14328 69805 1.603 360 1 0.63 1 110314 1.99 1 42984 1 67330 1 1.546 1440 1 0.19 1 135554 1.99 1 171936 1 -36382 1 -0.835 t I 1 1 UPPER POND CALCULATIONS WITH REVISIONS TO RESIDENCE INN SITE Project Name: Residence Inn - Oakridge 25th Project No.: 9097.01 By: FSW Checked By: Date: 4/24/97 SOUTHEAST DETENTION POND (BASIN A) Site Area = 10.06 ac Allowable Composite "C" 0.821 Developed Composite "C" 0.679 Developed Site Tc 10 min Allowable release 1.99 TIME (min) I (in/hr)l DEVELOPED INETALLOWABLEI RELEASED DELTA I DELTA VOLUME (cf) RELEASE (cfs) I VOLUME (cf)l VOLUME (cf)l VOLUME (ac-ft) 5 9.40 24078 1.99 597 23481 0.539 10 7.29 37347 1.99 1194 36153 0.830 15 6.16 47337 1.99 1791 45546 1.046 20 5.20 53280 1.99 2388 50892 1.168 25 4.60 58915 1.99 2985 55930 1.284 30 4.17 64089 1.99 3582 60507 1.389 35 3.80 68137 1.99 4179 63958 1.468 40 3.50 71723 1.99 4776 66947 1.537 45 3.25 74925 1.99 5373 69552 1.597 50 3.00 76846 1.99 5970 70876 1.627 55 2.80 78895 1.99 6567 72328 1.660 60 2.60 79920 1.99 7164 72756 1.670 70 2.30 82481 1.99 8358 74123 1.702 80 2.05 84018 1.99 9552 74466 1.710 90 1.88 86682 1.99 10746 75936 1.743 100 1.70 87092 1.99 11940 75152 1.725 110 1.56 87912 1.99 13134 74778 1.717 120 1.43 87912 1.99 14328 73584 1.689 360 0.63 115269 1.99 42984 72285 1.659 1440 0.19 141642 1.99 171936 1 -30294 -0.695 Page 1 VOLUME [1 1 Project No.: 1 9097.01 By: DWK Project Name: IRESIDENCE INNI Date: 4/30/97 Pond A - Detention Volume - Utilizing Current Equation Contour Surface Incremental Cumulative Elevation Area Volume Volume (ft.) (sq. ft.) (cu. ft.) (cu. ft.) 71.5 19211 0 0 72.0 27279 11563.71 11563.71 73.0 34735 30932.02 42495.74 74.0 40141 37405.43 79901.17 Total Volume = 1.83 ac-ft 73.0 42495.7 73.11 46236.3 73.2 49976.8 73.3 53717.4 73.4 57457.9 73.5 61198.5 73.6 64939.0 73.7 68679.5 73.8 72420.1 lukc O N p 11 73.9 76160.6 w o N v 74.0 79901.2 v Vo kkw�c rc alres Cresu. (�)a d e I n O n� i ncrcun•e e< D .1 P (� eel C0 0� toolctsl�n 1 6 N � (ai i n St'� ,vF `j 5, O. ( I , Z FCt ' Page 1 i f7 I ' RMINC Engineering Consultants ' 2900 South College Avenue Fort.Collins, Colorado 80525 303/226-4955 ' November 10, 1987 ' Ms. Susan Hayes Storm Drainage Department ' City of Fort Collins P.O. Box 580 Fort Collins, Colorado 80522 ' RE: OAKRIDGE BUSINESS PARK TENTH FILING Dear Susan: We are pleased to submit this Final Drainage Report for Oakrid e Business Park Tenth Filing. 5 ' If you have any questions or comments, please feel free to call. Respectfully, RBD, Inc. 1 d G. Mc h ' Project Man ger / C Z. Cort Ni kel Project Engineer ' Other Offices: Vail, Colorado 303/476-6340 • Colorado Springs, Colorado 303/574-3504 I 1 ' FINAL DRAINAGE REPORT FOR OAKRIDGE BUSINESS PARK ' TENTH FILING ' PREPARED FOR: ' EVERITT COMPANIES INC. 3000 S. COLLEGE AVENUE FORT COLLINS, COLORADO 80524 PREPARED BY: ' RBD, INC. ENGINEERING CONSULTANTS 2900 SOUTH COLLEGE AVENUE ' FORT COLLINS, COLORADO 80525 .1 1 1 11 INTRODUCTION ' LOCATION t oakridge Business Park Tenth Filing is located within the Oak - ridge Business Park on the southwest corner of oakridge Drive and Wheaton Drive. The legal description of the development falls within the Northwest Quarter of Section 6 of Township 6 North, ' Range 69 West of the 6th Principal Meridian. EXISTING CONDITIONS ' The site currently is being utilized as farmland and is covered with field stubble and native grasses. The property slopes to ' the south at a 2% grade and drains into an existing drainage channel. This drainage channel. runs along the south edge of the property and flows from west to east. Offsite flows enter the site in this channel through three 36 inch RCP's under oakridge ' Drive. Drainage flows leave the site through two 42 inch RCP's which lie under Wheaton Drive. Offsite Street Flows tributary to the site along Wheaton Drive and South Lemay Avenue are collected ' in an existing catch basin and enter the' site just downstream of the 3-36" RCP's through a 15" RCP. The site is roughly trian- gular in shape with improved streets along the north and east sides (ie. oakridge.Drive on the North and Wheaton Drive on the ' East.) The property south of this site is largely undeveloped at this time with the exception of two previously platted filings of the oakridge Business Park (see Exhibit. One). Construction is ' currently underway on the Eighth Filing. Storm drainage for these filings is being facilitated by a recently installed 15 inch RCP which is being relaid as a part of this project and will ' outfall into an existing catch basin on the Southeast corner of the site. Calculations for the capacity of this pipe and grated inlet are included in the Appendix. ' PROPOSED CONDITIONS When fully developed,the Filing 10 site (areas 3 & 5 of Exhibit ' One) will consist of two office buildings., a parking area and two large landscaped ponds. The storm drainage design included herein is for the entire subbasin identified as areas 3 through ' and the tributary street flow area shown on Fxh;hi design incorporates four separate facilities to nnP. The fi- dent detention volume to limit the localized flows dfrom fthe above described subbasin to .2 c ' upstream developed flows. Our modeling used an off -site flow of 68.12 cfs. The 68.12 cfs is a combination of the attenuated 100 year peak storm flow of 65 cfs at South Lemay Avenue and Harmony Drive and the addition of 3.12 cfs from the area just upstream of the site. (15.6 acres x .2 cfs/acre) This flow either needs to be routed through the designed ponds or bypassed around the ' ponds. Due to the large ponds required to route the storm through the ponds, it was decided to route the 68.12 cfs"around the site. I ' This was accomplished by providing separate inlet and outlet basins. The inlet basin receives water from the 3-36" RCP's that carry the attenuated offsite flows and is designed to pass the ' offsite flows without allowing flow passage into the uppermost pond. The outlet Junction Manhole provides for the transmission of the water offsite into the 2-42" RCP's under Wheaton Drive and also prevents water from entering the downstream pond. 1 1 11 1 1 1 6 s cts HARMONY ROAD fL- \4REA 2 \ ' �-- OAKRIDGE DRIVE FUTURE -POND j •� S 77 v AREA 1 1 ' "° rn P O�IQUc PjLOGK O z; '. rc, _� OAKRIDGE FlL,� BUSINESS _ > . EMI srI rJU DE T \ PARK. 10th FILINC POND S/ TC ARE 4' LOWER ND 2 POND 4 AREA 6 - 4th FILING 086N 8th FII,,I G 1 RULE DRIVE / _f1 EXHIBIT ONE ' DESIGN PROCEDURE The detention criteria for this site was derived from three pre-vious drainage studies. They are: Reference No. 1: ' McClelland Basin Master Plan by Greenhorn & Omara Inc., dated June 20, 1986. ' Reference No. 2: Final Drainage Report for Oakridcte Village P U D Filing ' No 2 by RBD, Inc. dated July 16, 1986. Reference No. 3: ' Final Drainage Investigation for Oakrid a Business Park (Preliminary Coovl by James H. Stewart & Associates, Inc. ' dated May 17, 1987. This site is required to detain the 100 year developed storm at a release rate of 0.2 cfs/acre. This outfall rate was developed by ' the City of Fort Collins Storm Drainage Department. The outfall rate was developed during the design of the oakridge regional Pond which abuts the. Union Pacific railroad embankment. This rate represents the most reasonable figure for development deten- tion upstream of the embankment based upon the cost -benefits of improvements downstream of the railroad embankment. ' DESIGN APPROACH The approach taken for the. drainage design of the Tenth Filing centers around the landscape ponds and accompanying outlet works. However, several assumptions should be clarified from the outset: 1. Drainage from the Fourth and Eighth filings will not enter the proposed detention ponds designed in this report. The elevation of the storm drain serving these two filings is too low to outfall into the ponds. Additional detention needed for these filings will need to be provided in the proposed middle pond described in Reference No. 3. ' 2. An additional detention and or site b site detention will be designed in the future to detain flows from the area north of Oakrid a Drive Areas 1 and 2., Exhibit One). This future pond will outfall at a rate of 0 2 cfs/acre for on - site flows plus 65 cfs offsite flow. 7-/4/5 ,) N D t/r ,¢S ' DES((7nJc-D ,4ND G0NST_gJ.4G7'cp 1'q-5 T- O F7 FoU0-1- f F__( tQ6r I 11 1 1 1- 0 I 1 1 3. The ponds designed in this report provide for a detention rate of .2 cfs/acre for Areas 3 through 6 and the tributary street flows shown on Figure 1. No on site detention will be required in these areas apart from that provided by these ponds. With these design assumptions in place, a further explanation of our design approach follows. Design of the bypass line for the 68.12 cfs offsite flow was based on utilizing 42" PVC "Spirolite" pipe. The inlet basin serves two functions: First, to preclude upstream flows from en- tering the detention ponds and secondly to allow "head" to build up to pass the incoming flow.' The outlet junction manhole serves two functions: First, it precludes water from entering the lower detention pond and secondly, it serves as the headwater basin to transport the offsite flows and the reduced onsite flows through the 2-42" RCP's downstream. The ponds are designed to not only provide adequate storage for localized flows but also to serve as visual enhancements to the site. Thus, each pond is designed to maintain a volume of water below the orifice pipes which control the release rate of stormwater to .2 cfs/acre. Realizing that stagnant water may have adverse environmental affects upon the site and downstream residents, the downstream pond has a circulation pump that con- tinuously recirculates water to the head end of the upstream pond reducing the adverse environmental impacts of stagnant water in the detention ponds. Designs on these facilities have not been completed. Manufacturers literature on the 42" PVC line state that a Man- nings N of 0.009 can be use4 for this pipe. However, using an "N" valve of 0.011 the pipe will pass 68.12 cfs under the present site conditions. (Inv. out = 66.2, Inv. in = 67.21, Headwater Elev. = 73.931). Calculations for the Hydraulic Grade line are included in the Appendix along with a chemical resistance chart showing the resistance of the pipe to most substances which at- tack other materials such as metal and concrete. Sizina of the ponds was based on the Rational Method. The area in acres, was calculated for each of the 5 separate sub -basins. Impervious areas and Pervious areas were then calculated wi in each sub -basin. Based on these areas, weighted "C" factors were then calculated for the entire area tributary to its respective pond. For example; the uppermost pond was designed to detain the flow from sub -basins 3 and 4 as well as the tributary street flows along South Lemay Avenue and Oakridge Drive The street had a "C" factor of .95 and Sub -Basins 3 and 4 had "C" factors of .57. The weighted "C" factor used for the entire basin was then: 95x2 28 acres + 57x1 6 acres + 57x6 07 acres/9.95 acres .66 I These "C" factors were then applied to the rational formula (utilizing a Cf = 1.25) in conjunction with Figure 3-2 of the City of Fort Collins Storm Drainage Criteria to obtain the Peak flow rate for the given time of concentration. The maximum dif- ference between the cumulative volume plotted against time and the maximum allowable release rate of .2 cfs/acre would then be the required pond volume. This was done for the upstream pond using a maximum release rate of 1.99 cfs. The required volume of the downstream pond was calculated by ad- ding the cumulative volume corresponding to a peak outflow rate Of 1.99 cfs from the upstream pond to all of the cumulative runoff volumes calculated by the Rational Formula for areas 5 & 6• This cumulative volume plotted against the maximum release rate of 1.99 cfs from the upstream pond and 2.49 cfs from the downstream basin (4.48 cfs total) would then be the required pond volume. These calculations indicate pond ac-ft. for the upper and lower printouts of these calculations labeled as Mass Diagram Method. are approximately 1.84 ac-ft an lower ponds, respectively. volumes of 1.66 ac-ft. and 1.7 ponds, respectively. Compute are included in the Appendix, Volumes of the detention ponds t 1.81 ac-ft for the upper and The peak outfall rates of 1.99 cfs and 4.5 cfs were maintained by ' selecting an appropriately sized orifice. Tables of discharge versus head are also included in the Appendix. ' To maintain the different working water elevations between the upstream and downstream ponds a retaining wall with the orifice cast -in -place was required. A stability analysis of the retain- ing wall is included in the Appendix. In the event the orifice plate on the upstream pond should plug, the crest. of the.retain- ing wall is depressed 4" for a length of 3. This will act as a broadcrested weir and limit the flows to the downstream pond to less than 2 cfs. Given the same scenario for the downstream pond, water will overflow the ponds and enter a grated inlet on the top of the junction manhole. These emergency bypass struc- tures assure passage of storm flows through the site. 1 1] RECOMMENDATIONS & CONCLUSIONS We recommend the following: ' 1. All storm drain piping, outlet works and sidewalk chases shall be constructed as detailed in this report ' and on the accompanying grading and drainage plan. 2. All grading should conform to that shown on the grading ' and drainage plan to promote positive and safe drainage within the site. 1 1 1 I APPENDIX CALCULATIONS 1 1 ir,c Engineering Consultants 1 1 1 1 1 1 1 1 i 1 1 1 i 1 1 1 1 CLIENT F_I ..11. 01.;_c44 �\ JOB NO. PROJECT )o.kr,..A r r.i.Y-c `O CALCULATIONS FOR MADEBY CHECKED BY DATE SHEET OF �_ H 1 1 MASS DIAGRAM METHOD for DETENTION VOLUMES i,'ROJECT: OAKRIDGE ESTATES FILING 10 OMMENTS: 100 YEAR STORM MAXIMUM ALLOWABLE RELEASE (CFS) = 1.99 I:ATIONAL EQUATION: 0 = CIA f= = 0.821 A(area) = 9.95 LIME OF CONCENTRATION 17.83 1 TIME CA I INFLOW OUTFLOW STORAGE (min) ---- -(in/hr) (cu ft) ----------------------------------- (cu ft) (cu ft) (ac ft) 1 5 8.16895 9.4 23036.43 597 22439.43 0.515138 10 8.16895 7.29 35730.98 1194 34536.98 0.792860 15 8.16895 6.16 45288.65 1791 43497.65 0.998568 1 20 25 8.16895 8.16895 5.2 4.6 50974.24 56365.75 2388 48586.24 1.115386 2985 53380.75 1.225453 30 8.16895 4.17 61316.13 3582 57734.13 1.325393 35 8.16895 3.8 65188.22 4179 61009.22 1.400578 1 40 8.16895 3.5 68619.18 4776 63843.18 1.465637 45 8.16895 3.25 71682.53 5373 66309.53 1.522257 50 8.16895 3 73520.55 5970 67550.55 1.550747 1 55 8.16895 2.8 75481.09 6567 68914.09 1.58205 60 8.16895 2.6 76461.37 7164 69297.37 1.590848 70 8.16895 2.3 78912.05 8358 70554.05 1.619698 8o 90 8.16895 8.16895 2.05 1.88 80382.46 82931.18 9552 70830.46 1.626043 10746 72185.1E 1.657.143 100 8.16895 1.7 83323.29 11940 71383.29 1.638734 110 8.16895 1.56 84107.50 13134 70973.50 1.629327 1 120 8.16895 1.43 94107.50 14328 69779.50 1.601917 360 8.16895 0.625 110280.8 42984 67296.82 1.544922 1440 8.16895 0.192 135513.0 171936 -36422.9 -0.83615 1 1 1 1 ' MASS DIAGRAM METHOD for DETENTION VOLUMES IPROJECT: OAKRIDGE ESTATES FILING 10,LOWER POND ;OMMENTS: 100 YEAR STORM MAXIMUM ALLOWABLE RELEASE (CFS) _ ' 2ATIONAL EQUATION: Q = CIA `- = 0.713 A (area) _ TIME OF CONCENTRATION = 15.96 4.48 ,INCLUDES ADDITION FROM UPSTREAM POND 12.43 'TIME CA I INFLOW OUTFLOW STORAGE ---- (min) (in/hr) (cu ft) (cu ft) (cu ft) (ac ft) ---------------------------------- 5 8.86259 9.4 25589.80 ' 10 8.86259 7.29 39959.56 15 8.86259 6.16 50926.09 ' 20 25 8.86259 8.86259 5.2 4.6 57691.76 64138.37 30 8.86259 4.17 70106.40 35 8.86259 3.8 74904.56 ' 40 8.86259 3.5 79224.15 45 8.86259 3.25 83144.92 50 8.86259 3 85736.31 55 8.86259 2.8 88460.63 ' 60 B-96259 2.6 90121.44 70 8.86259 2.3 93974.81 80 90 8.86259 8.86259 2.05 1.88 96764.68 100724.4 100 8.86259 1.7 102344.4 110 8.86259 1.56 104"389.8 ' 120 8.86259 1.43 105584.4 360 8.86259 0.625 162650.5 1440 8.86259 0.192 319042.1 11 ------------------------- 1344 24245.80 0.556607 2688 37271.56 0.855637 4032 46894.09 1.076540 5376 52315.76 1.201004 672i ) 57418.37 1 . 318144 8064 62042.40 1.424297 9408 65496.56 1.503594 10752 68472.15 1.571904 12096 71048.92 1.631058 13440 72296.31 1.659694 14784 73676.63 1.691382 16128 73993.44 1.698655 18816 75158.81 1.725409 21504 75260.68 1.727747 24192 76532.41 1.756942 E 26880 75464.41 1.732424 29568 74821.82 1.717672 32256 73328.42 1.683389 96768 65882.56 1.512455 387072-68029.8-1.56175 I 1 1 1 1 1 1 1 i 1 1 i i 1 1 1 1 CLIENT (, {� JOB NO. U3= PROJECT �l c, t�i.{ PAL` `O CALCULATIONS FOR 1� •..�i \Jy' MADE BY V•'` GATE ""CHECKED BY DATE BNEET _.L_ OF __ 1 1 1 1 1 .. 1 1 LOWER POND DISCHARGE CONTROL Discharge is controlled by a 10.75" 6 Orifice Plate with bottom set @ 69.5. Elev. cfs 69.5 0 Q= Cpp 2 h A 71 3.165 cfs — . 61 { q� 1 D2/4 72 4.42 cfs Use 12" Schedule 120 Steel Pipe I.D. = 10.75" UPPER POND DISCHARGE CONTROL Discharge is controlled by a orifice plate with bottom set at 71.5. Plate is 7" Elev. cfs 71.5 0 71.79 .579 72.08 .71 72.5 1.1 73 1.439 73.5 1.711 74 1.944 Use 8" Schedule 140 Steel Pipe I.D. = 7.001" « OvdHLt LALUULATIONS CLIENT /f� i 'C_z ' JTT RINC n1 13 JOB N0. PROJECTSJ CALCUUTIONSFOR $rp Engineering Consultants "''" ` MADE BY -DATE CHECKED BY -DATE ',At OF Z i 1 WESTt�N SIDECIUA�K C'/✓,lSt AxC,ac.� c cA b A R-6 PAVE'A . Cart PoSIre C 1 o.�z cJvosePo� Oda/ o.�s O.O_, 1 TorhL AREA A Da o.�z o.as ._. 1 /• 3S /3 0.0-70(1�.a4i = �3MIAJ U3t S.O M/IV p C/00 - CCU = 0.85 x g.JSe�s Lx) _ .2p j -----� n = o•a�r 3 ,Q� �, 3Qts T�ROP pR .2 OROP L`TSTCeAI f'N/�ic : A kt7t�ej PJWt^p ARt � I nel') eA (2c3m rrc C I.58 OAS /.Sp ' �sev n2cx o.72 -ror. Ak goo �eC'-PC'A = o .73 6,�S> 8.o 1 CLIENT _\ ' Joe No. U 3S O l y RMINC PROJECT �.2 ��-l.�y J----�__CALCULATIONS FOR to �-U•, ��.-�;�-� Engineering Consultants MAOE13YDATE Ib CHECKED DY DATE SHEET L- OF L I ' e A . z- - P. I IO'� I I h u L 1 ly I 1-+7r 1 —_ I * L r; r 1-I------ F'— t i , 1 LA J I tit 1 I ; :. ,. T - 4 ~I� L { { 1 I_ It 1. I I I 41 �. .. I --1 is i I 1 1 1 1 1 I 1 1 1 1 1 1 1 11 1 1 CLIENT �nl JOBNO. OAS _nyy PROJECT I „ CALCULATIONS FOR lwA.� T�t. •,,,�� MADEBY�DATE ,O CHECKED BY_DATC SHEET OF I A Yam' www?�r NCUWNc/[ — OAKRIOGE CENTER "`'/'i 'I / G�/F —, RETAIL P.U.D. a 4TH FILING 18. /NW 27}9] i4.F q9 A 32 942 OAKRIDGE \ _ a. RIP PIP Ga FIGHT Of .016 .95 T ta3 .w 1 wcr cMLWC,£ INRMMFt .,� , < A " Wn.,4-sos 4 F ZIA W I Y _ a I 1 1 � i DEFINITE SSWI�VIIJ •A- 111e1 •e• D L 5CONCRETE PAN SWAL a 0100 = 21.80 CFS AT DESIGN POINT 6 oDESIGN = 29.00 GEE = 133E OF 0100 SLOPE = 1.0E DEPTH = 1.05 FT 0100 = 763 CFS AT DESIGN POINT 8 OOESIGN = 10,15 CFS = 133E LP 0100 SLOPE = 1.4E DEPTH 0,57 FT / s / - OAKRKHE 1111.11119111198 PARK IOTH FILING �i LOT 8 i , SW LE 1'\- sTE sEHON THIS sI \ OWIDS!B JS / TEMPORARY I A\ cY SLOAR W EOCC INT r \ BY SEPgpdi[pOMIEhr `,` \\� 1 N xsv / i JF \ / IF I I� BOOK 1689, PAGE 99E � eli! eWYl T P `GRASS LINED 3 01M = 2.63 CFS AT DESIGN POINT 8 ODESIGN = 10.15 CFS = 133E OF 01 DO SLOPE = 1.2E DEPTH = 0.86 FT N = DICK UPPER NN. POND BOOK 1689, PAGE 99E � eli! eWYl T P `GRASS LINED 3 01M = 2.63 CFS AT DESIGN POINT 8 ODESIGN = 10.15 CFS = 133E OF 01 DO SLOPE = 1.2E DEPTH = 0.86 FT N = DICK UPPER NN. POND /r. 3 i r rya �!\0' so E ? F SEE sEc / 4F// s� NIS SNEE 16 =0 -% EASEYMEN AGE LOWER POND a 4PNIN "M9Pa[FI MWISW665 / / / nAKRIDGE BUSINESS PARK / tlTH FILING P.U.U. eecnoe 6D / —555'— 15SIDEWALK 775 )T DODVO\ GRASS LINED ` SUBDRMN SWALE fQN 0100 0.90 GIES COESIGN IF 1.20 CPS AA 133E OF 0100 SLOPE = 0.5E DEPTH = 0.27 FT N = 0,047 IMN off _E ME �1 INSTALL 24" STORM SEWER PER PLAN AND PROFILE SHEET 9. © INSTALL PRIVATE 8- ADS STORM SEWER AND AREA INLET PER PLAN AND PROFILE SHEET 9. �} INSTALL 15- ADS STORM SEWER PER PER PLAN AND PROFILE SHEET. ® INSTALL 4' CONCRETE SIDEWALK CULVERT PER CITY OF FORT COLLINS STANDARD D 12 OS RECONSTRUCT 6 SIDEWALK AS SHOWN IN OAKRIDGE BUSINESS PARK, IOTH FILING © REMOVE EXIS71NG 4 SIDEWALK CULVERT. INSTALL 2' METAL SIDEWALK CULVERT PER CITY OF FORT COLLINS STANDARD D-10. ® INSTALL 6- PERFORATED ADS SUBORAIN PER DETAIL SHEET t 50 25 C 50 SCALE: 1' = 50 LEGEND EXISTMC PIPES PROPOSED STORM SEWER 0 SIDEwuK CULPRIT PROPOSED MIST LOCATION QDESIGN POINT F DAS'N CRITERIA f� » RUNOFF COURICIENT AREA IN ACRES �y FLOW DIRECTOR oNED EARN BOUNDARY `SUBDRAIN too MRE FENCE ----. -„—_ BOARD FENCE - EXISTING D.S CONTOUR 'Q `- - EXISTING 1' CONTOUR - PRCPCED 0.5' CONTOUR 4/00 — PROPOSED 1' CONTOUR LIGHT PONT STORM MANHOLE 8 a R b M m kk� �m�sa z w 6 y a , w ? € 3 m �ODy Fig 4T W�gS¢ 0 F 0=S z NAotia r e M II n vI a n FINAL PREPARED UNDER NE DIRECT SLAWERMSKIN 6 m A In ED FOR L'OWSFR(.C'/eJW' OCTOBER 24. 1997 LINED 0100 = 150 CFS ODESIGN - 2.DO CFS = 133E OF 0100 SLOPE - 0.5E DEPTH - 0.41 FT N = 0,045 N N U O ? Z 0z LILL Z 0 Kc N FRELOEOt 90017 WATERMAN. PE DAIS J Z J CQgADO PC N0. 31755 <a Q• FLOP ANDON 9 OF A ENOMFFANO. LM :CL D_ � � Z < a!City of Fort Collins, Colors Co UTILITY PLAN APPROVAL < Z D] < W APPROVED: U CC Dlrciu of Emg0w1nq DIO, W (� H CHECKED BY: Wplm ! WortoaW, DC IY Dele CHECKED BY Y Q ILL. UHRY Dole 0 CHECKED BY Rohe IF Rgeetm Daie CHECKED By. SHEET 4 OF 12 Oa1a .UB NO. REV. CHECKED BY: 9097,01 DI, 0 Rim half d Ism ur aa.. /YILIL We Sa+.,J MillPLAN NEW had M We sa+mlm.t SECTION Al oW a emw CURB INLET FILTER `0 set eqW ur e.M GRAVEL ':s RMr NWe mx nre r t •w the ee- poer rllw N an Aw thol to a rn- CITY OF FORT COWNS. COLORADO i M NO ebx ntw meow STORMlif UTILITY isdawe rx.e..e rmm a /tw W say If rwea, D-25 with 2 Stakes NA, Dal -P�t A All SECTION A -A PLAN NEW AIR F- PROFILE NEW GiMa' an Monte t ermd.. d NAN... STRAW BALE DIKE �(,n rY) Be If anx mM CIIANEL APPLICATKIN mm21 OR anal phyphy par muer pr..e a panlw by OTY tS FORT DOWNS COLOR m. cnx..wR oewm rx em4x .rI R1F(%81WATER UTILITY 1. Excawte Trentll. 2. Place and stake 4' Minimum Depth Stra Slog la nvkN 3. Bo EABII and Compact Excowte0 Soil T I�1 mew Bean ewes Ilui Isle CRUYS-SECTION NEW N r 1. NOW IT 0x are ANe an,An.M m .tx nmero t ma As 0.25 me Ipx W M e( tmlx e 2 ANpf rgeu, mH'4MI (A s ) the nlxa enx rn ill Inawl 3 aAll sals, pat In rWg onxt2a npo.n A,r AM En&w g 0iwv, As STRAW BALE DIRE GENERAL !INSTALLATION SECTION NEW .a= �E CONSTRUCTION ENTRANCE . ,aNSIMr9wAatri TR M STORM rLTESap£ LENNMMtEMEACH f HAB« FILLED VEESEDIENTSN evoalED IN IN ARE. viRU,ARIO a 5[DI4EX! BARN « OMER FILTERING uEeIDPE 2. MOsoN RNma NAmRXANW IS THE REEDONv9uTr OF ME I EIEEWER. DRAINAGE SUMMARY TABLE C«6T1I11C11aN8fWFHCE W TA DrawC aevcva rm rw+ ,, cur,c,ED atYm utrt ro,ii v�,piwawxa^+r+w�r.w,aa,+ww s roves, rrw ♦�. m aex+x4rcx[� w� Mesa A sal AM Ma, i AM. way al MINE � cl A. I wited Ali km �MUCTI� prM 5 Mt AueoOF "FTArp a, Ef8ffiB r A,arasoeraanMNAdTm 11sxTe,c ym DESIGN PONT AREA DENG. E%I AREA (ACRES) 0.016 C2 0.95 C100 LW TO (2) MIN 5.0 PC 100) MIN) 1D.0 0 (2) DES 0.05 0 (100) CFS 0.12 2 E%2 0.041 0.95 LW 50 10.0 0.12 0.29 I I It Of E%4 E%5 1630 2.Be 0.279 0.60 0.57 0.57 0.75 0.71 OJt 12.11 IFS It One 12.1 10.0 100 226 2.38 39 605 TO 35 141 A 0.075 0,44 055 8.2 10.0 0.09 0.30 2 3 5 7 B C 0 E 0.369 0.085 0.323 0.868 0)2 0.66 0.66 0.75 090 a.83 0.83 0.94 62 5.6 64 60 10.0 10.0 100 160 078 0,17 52 J7 236 0.50 1.89 5.76 8 F 0.183 0.59 0.74 5.1 _ 10.0 34 09. 9 G 0.288 0.56 0.70 5.0 10.0 _0,51 1.43 0. Ol Ak n 19.0 AL 38 R .90 0.06 71- b 2.70 2 E%2,0 0.411 4 E%3.E%4.0 D. O59 OJ4 16.5 HC4 443 17.88 5 E%3.E%4 4.0]7 Q59 0]4 167 12.5 4.83 19.54 C,D 6 E%2E%3.E%s ♦.486 0.60 0.75 20 t2J 5.39 2L85 B.C.0 E%5.E L0 1 _0JO 0.88 t0.8 t0.0 T96 717 1.329 6.1970.62 0.69 086 OJB 13.2 A.2 11 7 12.9 205 ).SB 7.63 30.69 8 9 E%S,E.F DLL Weese4n CaraebTANA (eerrk'%1a1r) IIIII na1.4 [A Grle I A L Cned E,Wr NIM VIEW o..Nteer� ca••w 5�p,mh RadF-Gael fM.r we Wdx.� - SECTION A# Gal roles. rpm AREA INLET FILTER w.l mw. u new lately nx nmm r Mparep y dGRAVEL depth FAAceva Fl od som e ve dBI I CITY OF FORT COLLINS, COLORADO to a t eox.nwtw jHMAMSTORMWATER UTILITY tll�IIFVneuurep 3.('7 2 seautehl we wave .... ce m.wduleer IsewR moves rrmm Ii way a rows. D'24 e Judy. 1996 Judy.6 The S+i U swal m.tl AM ne40eo at xt C Iw,e 2: If pnx I'mrxm,..1.aa an OF ,.te. Ad aM wMew aAt Imo n e e tur0inq e (O AInm4. ping. Oro 9t+).offAll al Haiti mi cal aeal al ,e m me be was pi ;M.a.heT Mapenithey be pia �. W. ram Fa mn .rN..sa. owWe or tee ate d..a damn eme ch,1.rony HDARR, bwp�u Final ay eNodpamYp, s,% All shad MT1 w9HmN Ism w � rating ou dill" mN ,fibin, AT land m1 ANOSIF CROPS Dena ff tha an Ro�i e"Far ART rn m.wray, ear wet x 4aly (e 9m+^d]'mA,li.+la^yeapF9. 0") la "Nepal. ant WANIM epmeed by e larm n U111ty. The w tyMw be +maw m4 mowtnu met w .1 ,s ry 'tr.l,�hee 1 +md-,mwd x 6 d u2" llt'71'w ,dWct% mmaialpy elxmTrvM +Nm N n iv east m p t$ apt nl Wmx , as aptiont by the City of FINE Cale, E.Rna,r g OWx Mm 1. n twnpwy(etmpt�) Ww eMbe moief FW M ar ,a.tw o ralt..wr ,men .,.� ecma Abdul Ad n x o^ ppowE a Mary the a pM dgw Oe o manna and f lean fro oa lot In mace ythY aN,M AIR my 600og y No eA d M1IspA.�mt Mandu hmawrt( r)el 0 xdNpe rwanmRhmoayl Isle na, a,e Mal be NET tMM My " etadpw rmtannR enw w idea M d. em.d and mu enee. City 6dYmu pc04 Ue tmA g. a4 be 0 alma of M" er m� they m mmexW ant, City aneete by orfrom r Mae. by xa .xe.l rowlt mn a Cleww mIsSatiny by Ind em4 tx FINAL FLYP OL' OCTOBER 24,, 24, 199 1997 {lama« =n VAIW M. v.L of mg P.E NJ. 312k5 �r« .AND ON q 6 A DIPEAWAa L1aM0 CN 1 OF A EIIPEAN4 LA. City of Fort Coiling. Colorado UTILITY PLAN APPROVAL APPROVED Dnedw It G9Aeeea9 Dare CHECKED BY warn a woaeemx utility Data CHECKED BY: stamwmx utetr Data CHECKED BY Diana a Re,remsin Dote Ar �IAt M as a€w S I d € N x ANa by 0 I € An o FS CO .0 z#Nra�WiR cl all �$OM at 0 00LO Of W ` V X, z 0 z z O VI S n U O-D W z al (n J JH oo W Of a a-D W w Of z n QZ W W zO � d Of 0 LOT Q W SHEET 6 OF 12 CHECKED By 0