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HomeMy WebLinkAboutDrainage Report.,. •.. i' • ....... .... ·. I .. . . _,., -.. Drainage Report FOR Christ United Methodist Church Phase III 4203 State Highway No. 6, South College Station, Texas April 24, 2006 Revision No. 1-May 24, 2006 Prepared For: Christ United Methodist Church 4203 State Highway No. 6, South College Station, TX 77845 Prepared By: Rabon Metcalf Engineering P.O. Box 9253 College Station, TX 77845 RME No. 198-0272 Drainage Report FOR Christ United Methodist Church Phase III 4203 State Highway No. 6, South College Station, Texas April 24, 2006 Revision No. 1 -May 24, 2006 Prepared For: Christ United Methodist Church 4203 State Highway No. 6, South College Station, TX 77845 Prepared By: Rabon Metcalf Engineering P.O. Box 9253 College Station, TX 77845 RME No. 198-0272 Drainage Report -Revision No. 1 Christ United Methodist Church Phase ill TABLE OF CONTENTS: 4203 State Highway No. 6, South College Station, Texas PAGE 1.0 General Information ...................................................................................•................................................... 1 I. I Scope of Report and Proposed Development ........................................................................................... I I .2 Site and General Location ........................................................................................................................ I I.3 Description of Existing Conditions .......................................................................................................... I I .4 Existing Drainage Patterns ....................................................................................................................... 2 2.0 Watersheds & Drainage Areas ...................................................................................................................... 2 2. I Pre-Development Watersheds & Drainage Areas .................................................................................... 2 2.2 Post-Development Watersheds & Drainage Areas .................................................................................. .3 3.0 Stormwater Hydrology ......................•............................................................................................................ 3 3. I Rational Formula and Methodology ........................................................................................................ .3 3.2 Stormwater RunoffQuantities .................................................................................................................. 6 4.0 Detention Facility & Routing .......................................................................................................................•. 7 4.I Detention Facility Criteria ........................................................................................................................ 7 4.2 Methodology ............................................................................................................................................ 8 4.3 Detention Facility Storage Area ............................................................................................................... 9 4.4 Detention Facility Outlet Structure ........................................................................................................... 9 4.5 Routing Results and Conclusions ............................................................................................................. 9 5.0 Certification ..................................................................................................................................... 11 ATTACHMENTS: Vicinity Map Lick Creek Drainage Basin FEMAPanel Drainage Area Map "X" Drainage Area Map "P" Hydrologic/Hydraulic Modeling Using HydroCAD 198-0272 Drainage Report-Rev I Page -i Drainage Report-Revision No.1 Christ United Methodist Church Phase ill 4203 State Highway No. 6, South College Station, Texas 1.0 GENERAL INFORMATION 1.1 Scope of Report and Proposed Development: This report addresses the drainage improvements, including associated detention facilities and structures, for the Christ United Methodist Church, Phase III development conditions. Currently, the site is developed with primarily two buildings and supporting drives, parking and sidewalks. The first is a 26,997 square-foot building that is the "Existing Sanctuary" with offices and educational classrooms. The second main structure, "Annex Building", is a 47,484 square-foot building that is used for additional educational spaces, administration, and the church's fellowship hall. The proposed Phase III is anticipated to consist of a 48,170 square-foot ''New Sanctuary" building (1,680 seats) with additional classrooms, meeting halls, and offices with associated site improvements. Associated site improvements include, but are not limited to, parking lots, drives, sidewalks, landscaping, etc ... The proposed development and drainage improvements are designed and analyzed in accordance with the criteria outlined in the "Drainage Policy and Design Standards" (DPDS) manual of the City of College Station (CoCS). 1.2 Site and General Location: The proposed development, Christ United Methodist Church, Phase III, is wholly contained on Lot 1 & 2 of the Barron Park subdivision consisting of 24.82 acres. The property is bordered by State Highway No. 6 (East Bypass) to the west. All property immediately adjacent to the site (north, east, and south) is currently undeveloped. Access to the tract can be accomplished from the west by means of the East Frontage Road of State Highway No. 6. A Vicinity Map, for this project site, is provided and located in the "Attachment" portion of this manual. This map is being provided as an aid in locating the project site. Drawings describing the work and its specific locations are contained in the Construction Drawings prepared by Rabon Metcalf Engineering, College Station, Brazos County, TX. These Construction Drawings are included as part of this Drainage Report by reference. 1.3 Description of Existing Conditions: The project site is contained within the watershed of Lick Creek and at the head-works of an unnamed tributary of the South Fork of Lick Creek. The Lick Creek Drainage Basin map is provided in the "Attachment" portion of this report. The project site does not lie 198-0272 Drainage Report-Rev 1 Page -1 Christ United Methodist Church -Phase III Drainage Report -Rev. No. 1 Rabon Metcalf Engineering May24,2006 within the 100-year floodplain as graphically depicted by the Federal Emergency Management Agency (FEMA) -Flood Insurance Rate Map (FIRM) Community/Panel number 480083 0201D, with an effective date of February 9, 2000. A portion of this FIRM Panel map is located in the "Attachment" section of the Drainage Report. The 24.82-acre tract is a moderately well sloping (approximately 2%) developed site with area inlets and underground drainage systems that convey runoff to the head-works of an unnamed tributary of the South Fork of Lick Creek. This unnamed tributary currently extends southeast into the property approximately 100 linear feet and departs the property approximately in the middle of the north property line. Improved areas, that consist of impervious cover, (i.e. buildings, parking/drives, sidewalks) constitute approximately 9.92-acres. Improved areas that are covered with landscaping and sod are approximately 4.30-acres. The remaining 10.60-acres is unimproved with land-cover general consists of open grassy areas with some thick brush, weeds, and trees at the upstream of the unnamed tributary. Elevations range on the site from approximately 282' Mean Sea Level (MSL) to approximately 298' MSL. 1.4 Existing Drainage Patterns: Drainage to and through the site is provided by surface parking and sub-surface storm drains from the existing developments. Outfalls from these drainage structures drain to the existing unnamed tributary at the north end of the property. This unnamed tributary drains in a northwesterly direction. This unnamed tributary is well defined and natural in nature. Runoff then drains into Carters Creek, thence to the Navasota River, thence to the Brazos River and ultimately to the Gulf of Mexico. 2.0 WATERSHEDS & DRAINAGE AREAS 2.1 Pre-Development Watersheds & Drainage Areas: As previously discussed, the subject 24.82-acre tract is located in the Lick Creek Drainage Basin (reference "Attachment" section of report). As shown, the project site is located near the confluence of the South Fork of Lick Creek but it is also at the upstream limit of the unnamed tributary reach and at the drainage divide of Lick Creek and Spring Creek. Since the project site is located on the before stated drainage divide no additional runoff will be received to the site. Therefore, for pre-development conditions one (1) drainage basin, contained within the "Attachment" section of the Drainage Report, was considered and analyzed and is described as follows: Drainage Area Map "X" -This drainage area consists of the 24.82-acre tract for pre- development or existing conditions. Analysis of this drainage area will provide runoff characteristics for the project site at its current developed state. This runoff data will be the "benchmark" data so that increased runoff can be measured from. 198-0272 Drainage Report-Rev 1 Page-2 Christ United Methodist Church -Phase llI Drainage Report -Rev. No. 1 Rabon Metcalf Engineering May24,2006 NOTES: A detention facility was constructed for the "Annex Building", formerly known as the Desert Hills Facility, which is wholly contained in Drainage Area "X". RME requested a copy of the Drainage Report, from the CoCS Planning & Development Services, but no copy was on file. It is assumed that this subdivision's detention pond meters runoff at pre-development rates which existed prior to this development. Therefore, the runoff coefficient, for areas encumbered by the "Annex Building" and associated facilities, will be set an estimated pre- development "C". With the construction of the "Existing Sanctuary" a drainage study was performed by Hester Engineering Company (October, 1997) and obtained from CoCS. An evaluation of this study reveals that no detention was required for this facility and its associated improvements. This was approved since reported information showed that the increase runoff did not noticeable elevate the Water Surface Elevations (WSE) of the unnamed tributary. Therefore, the runoff coefficient will be set at current conditions for existing condition runoff calculations. 2.2 Post-Development Watersheds & Drainage Areas: For post-development conditions two (2) different drainage basins, both contained within the "Attachment" section of the Drainage Report, were considered and analyzed which are as follows: Drainage Area Map "Pl" -This drainage area consists of 2.25-acres of land located at the northeast comer of the property, which will be left undisturbed by this development. For proposed conditions runoff from this drainage area will be released from the site undetained, as it currently exists. The hydrologic data generated from this drainage area will be added to the runoff values of Drainage Area "P2" and compared to the runoff values of Drainage Area "X". Drainage Area Map "P2" -This drainage area consist of the remaining 22.57-acres of land contained wholly within the 24.82 acre property. During proposed conditions this runoff will be conveyed by means of surface features and an underground drainage system to a new detention facility. Runoff will then be metered out of the pond to the same discharge point of Drainage Area "X''. This drainage area generally is comprised of the developed area which would include the "Existing Sanctuary", the "Proposed Sanctuary", the "Annex Building", and all associated parking, drives and sidewalks. 3.0 STORMW ATER HYDROLOGY 3.1 Rational Formula and Methodology: The Rational Method and formula (Q=CIA) is one of the more frequently used methods to determine the peak runoff from a watershed and is typically reliable for small watersheds (< 50 acres). The Rational Method generates hydrologic data based on drainage area geometrics, surface conditions, and rainfall intensities. The Rational 198-0272 Drainage Report-Rev 1 Page -3 Christ United Methodist Church -Phase III Drainage Report-Rev. No. 1 Rabon Metcalf Engineering May24,2006 Method will be employed to determine both pre and post-development conditions and it is explained further as: Q=CIA where, Q = peak runoff rate (cubic feet per second); C = runoff coefficient -This represents the average runoff characteristics of the land cover within the drainage area and is a dimensionless coefficient. Runoff coefficients are interpolated from Table III-1 of the DPDS or from Table 2.1 or 2.2 of the City of Bryan (CoB) Drainage Design Guidelines; I= average rainfall intensity (in/hr); A = area of land that contributes storm water runoff to the area of study (acres); RUNOFF COEFFICIENT "C": The pre-construction runoff coefficient "C" for the 24.82-acre tract (Drainage Area "X") is approximated to be 0.55. This coefficient was estimated from CoB Drainage Design Guidelines, Table 2.2 by comparison of runoff surfaces types to percentage of land coverage and total drainage area. Calculations for this coefficient are as follows: Drainage Area "X" Runoff Coefficient "CWTo:;_ 4.77-Acres-Concrete Pavement and Rooftops 7 "C" =0.90 2.06-Acres-New Lawns Graded to Drain (2% to 7%) 7 "C" = 0.39 17.99-Acres -Undeveloped (Includes all of "Annex Building" area) 7 "C" = 0.48; (4.77/24.82) x (0.90) = 0.173 (2.06/24.82) x (0.39) = 0.032 (17.99/24.82) x (0.48) = 0.348 Weighted runoff coefficient 7 "CWTD" = 0.173+0.032+o.348= 0.55 The post-construction runoff coefficient "C" for the Drainage Area "Pl" and "P2" are approximated to be 0.48 and 0.76 respectively. These "weighted" coefficients were determined by comparison of runoff surfaces types to percentage of land coverage and total drainage area. Calculations for each coefficient are as follows: Drainage Area "P2" Runoff Coefficient "CWTD": 13.13-Acres-Concrete Pavement and Rooftops 7 "C" =0.90 5.42-Acres-New Lawns Graded to Drain (2% to 7%) 7 "C" = 0.39 4.02-Acres -Undeveloped 7 "C" = 0.48; (13.13/22.57) x (0.90) = 0.582 (5.42/22.57) x (0.39) = 0.094 ( 4.02/22.57) x (0.48) = 0.085 Weighted runoff coefficient 7 "CWTD" = 0.582+0.094+0.085= 0.76 198-0272 Drainage Report-Rev 1 Page -4 Christ United Methodist Church -Phase ill Drainage Report -Rev. No. 1 TIME OF CONCENTRATION "Tc": Rabon Metcalf Engineering May24, 2006 The Time of Concentration "Tc" at the site is used to determine the intensity of the rainfall event for the corresponding drainage basin. "Tc" is defined at the time required for the surface runoff to flow from the most remote point in a watershed to the point of analysis. The "Tc" is the summation of the flow time for shallow overland flow and/or concentrated flow to the lower reach of the watershed. Overland sheet flow is a method developed by Overton and Meadows and is typically used for flow distances of 300 feet or less. Concentrated flows are estimated by velocities determined by use of the Manning's Equations. These two types of flow time calculations are further explained as follows: Overland Sheet Flow, T = {0.007 (n L)6.s} I {Pi112 s0•4} where, T =travel time (hours); n =Manning's roughness coefficient -This represents the flow-ability of runoff across and surface and is a dimensionless coefficient. These coefficients are obtained from Table 2.3 of the CoB Drainage Design Guidelines; Pi= ith-year recurrence interval for the 24-hour rainfall depth (inches) -Rainfall depths are obtained from Table 111-3 of the DPDS or from Table 2.5 of the City of Bryan (CoB) Drainage Design Guidelines; S =land slope (feet/foot) Shallow Concentrated Flow, T = D/(60V) where, T =Travel time (minutes); D =Flow distance (feet); V = Average velocity of runoff (ft/sec) -These values are determined from interpolation velocities recorded in Table 111-2 of the DPDS; Time of Concentrations "Tc" for each drainage basin are computed and summarized below in Table #3 -Drainage Basin "Tc". The minimum "Tc" used for any drainage area will be ten (10) minutes. TABLE#l SUMMARY OF "Tc" -Overland Sheet Flow Overland Average Flow Land Travel Drainage Manning's Distance Pi Slope Time Area I.D. "n" (L) (100-year) (S) (Tc) x 0.18 220 11.0 0.0136 0.223 Pl 0.18 300 11.0 0.3670 0.077 P2 0.18 220 11.0 0.0330 0.157 198-0272 Drainage Report-Rev 1 Page -5 Christ United Methodist Church -Phase ill Drainage Report -Rev. No. 1 Rabon Metcalf Engineering May24,2006 TABLE#2 SUMMARY OF "Tc" - Shallow Concentrated Flow Flow Average Shallow Drainage Distance Velocity Concentrated Area I.D. (D) (V) Time (Tc) x 800 3.5 3.81 Pl n/a n/a n/a P2 800 3.5 3.81 TABLE#3 DRAINAGE BASIN "Tc" Shallow Drainage Drainage Overland Concentrated Basin "Tc" Area I.D. Flow Time Time (min) x 0.223 3.5 16.9 Pl 0.077 n/a 4.6 P2 0.157 3.5 12.9 1) The minimum "Tc" used will be 10 minutes; RAINFALL INTENSITY "I": Rainfall intensities "I" are the average rate of rainfall in inches per hour for a given rainfall event. The duration of "I" is assumed to be the computed Time of Concentration "Tc" for each respective drainage basin. Rainfall intensities can be determined by use of intensity-duration-frequency (IDF) curves or from intensity equations which are provide in the TxDOT Hydraulic Manual. 3.2 Stormwater Runoff Quantities: Stormwater runoff quantities were calculated using the Rational Method, the above calculated components of the Rational formula, and with the assistance of the Hydralogic/Hydraulic stormwater modeling program HydroCAD. These runoff values are summarized below in Table #4 -Drainage Basin Runoff Quantities. Hydrologic/Hydraulic Modeling Using HydroCAD and its supporting data is contained the "Attachment" section of this Drainage Report. TABLE#4 DRAINAGE BASIN RUNOFF QUANTITIES Drainage Rainfall Area Drainage Drainage DIFF Event (X) Area (P 1) Area (P2) Pl+P2 (Ptotal-Xl) (yr) (cfs) (cfs) (cfs) (cfs) (cfs) 2 58.71 6.08 95.91 101.99 43.3 5 71.83 7.45 117.36 124.81 53.0 IO 80.89 8.38 132.16 140.54 59.7 25 92.51 9.59 151.14 160.73 68.2 50 104.72 10.85 171.09 181.94 77.2 100 109.28 11.33 178.53 189.86 80.6 198-0272 Drainage Report-Rev 1 Page-6 Christ United Methodist Church -Phase ill Drainage Report -Rev. No. 1 4.0 DETENTION FACILITY & ROUTING 4.1 Detention Facility Criteria STORAGE: Rabon Metcalf Engineering May 24, 2006 1. The storage ability of the detention facility is such that it can adequately detain the receiving stormwater runoff, from upstream drainage areas, so that runoff from the project site is controlled to pre-development "existing" conditions. The storage requirements are more fully explained in the following section; 2. The maximum storage depths for design and ultimate conditions shall be as follows: Facility Location Design Hydrograph Ultimate Hydrograph Parking Areas Rooftops Landscaped Areas 0.83 ft 0.50 ft 3.0 ft 1.5 ft 1.0 ft 4.50 ft 3. All detention facilities located on natural streams or water courses that are desgined with a permanent storage component shall meet all criteria, in terms of design and construction, for Dams and Reservoirs as required by the Texas Commission on Environmental Quality (TCEQ); 4. Detention facilities shall have an additional 10% in storage to account for sedimentation, expect those located in parking areas or rooftops. OUTLET STRUCTURES: The detention facility outlet structure is designed so that the system can be drained by means of gravity. Discharge velocities shall be verified that they are below the minimum velocities receivable by the type and nature of the receiving system or attenuated so that they are below these minimums. PHYSICAL CHARACTERISTICS: 1. Side slopes shall not exceed 4:1 for vegetative cover and 2:1 for non-vegetative cover; 2. Bottom slopes must be 20:1 (5.00%) or steeper to low flow outlet; 3. A low-flow invert shall be provided for all facilities which have a vegetative cover at the facility bottom. The low-flow invert shall conform to Section VII of the DPDS; EMERGENCY OVERFLOW: 1. The geometry of the emergency overflow shall be that of an rectangular weir; 2. Surface treatment of the overflow weir shall be consistent with the expected velocities at ultimate conditions. Proper treatments shall be provided to accommodate or attenuate the discharge velocities; 3. A minimum of 0.5 feet of freeboard shall be provided around the perimeter of the detention facility as measured between the maximum water surface elevation and the pool elevation and the ultimate conditions. 198-0272 Drainage Report-Rev 1 Page -7 Christ United Methodist Church -Phase ill Drainage Report -Rev. No. I 4.2 Methodology: Rabon Metcalf Engineering May24, 2006 The purpose of the detention facility is to store the increased runoff, created by the impervious and improved areas, and discharge it at a rate so that the immediate downstream structure and/or property experiences decreases or no change as compared to existing conditions. Using the peak runoff rates, generated and illustrated in Section 3.2 of this report, hydrographs for each rainfall event and respective drainage basin were created. These hydrographs were constructed by means of triangular approximation which is method is limited to smaller watershed located within the secondary drainage system of a major watershed. Other asswnptions and geometric conditions that are used to build these hydrograph are as listed below. Using this data, and inputting it into HydroCAD, approximate hydrographs were determined for each drainage basin at selected rainfall events. Hydrologic/Hydraulic Modeling Using HydroCAD section contains these hydrographs and is located under the "Attachment" portion of this docwnent. Triangular Approximation: 1. Peak Runoff (Q) occurs at "Tc"; 2. The outflow portion of the triangular hydrograph is Tc x 2; Using this information the storage volwne of the detention facility can be determined. This storage volwne shall be such that the peak discharges of the development hydrograph, or the routed hydrograph, from the detention facility be equal to or less than the ''target discharges". For the this project, at fully developed conditions, the ''target discharges" shall be such that the routed flows from Drainage Basin "P2" are equal to or less than the peak discharge rates of Drainage Basin "X" less the discharge rates of Drainage Basin "Pl". Algebraically written the "target discharges" shall be as follows. These ''target discharges" are also computed and summarized below in Table #5 -Target Discharges. "Target Discharge"= X-Pl TABLE#S TARGET DISCHARGES Rainfall Drainage Drainage Event Area Area (Pl) Target (yr) (X) (cfs) (cfs) Discharges ( cfs) 2 58.71 6.08 52.6 5 7 .83 7.45 64.4 10 80.89 8.38 72.5 25 92.51 9.59 82.9 50 104.72 10.85 93.9 100 109.28 11.33 98.0 198-0272 Drainage Report-Rev I Page -8 Christ United Methodist Church -Phase III Drainage Report -Rev. No. I 4.3 Detention Facility Storage Area: Rabon Metcalf Engineering May24, 2006 The area chosen for the detention pond is at the lowest point of the property which is also the head-works of an unnamed tributary of the South Fork of Lick Creek. The location of this pond is located in approximate middle north property line. At this location the ''target discharges", as determined and described above, in conjunction with the proposed detention facility will adequately maintain the project's pre-development runoff rates. By modify the cross-section of this existing unnamed tribuatary and installing a bermed wall and restricting orifice the required detention volume of 86,693 cubic-feet could be obtained. The minimum pond elevation, at the outlet, will be set at 279.00'. This will allow the pond to be fully draining. The maximum pond elevation is 285.60' with a maximum pool elevation of 285.06'. This will accommodate 0.50' of freeboard which meets the minimum requirement. All backslopes will be at 4:1 sideslopes with the pond embankments at a 2:1 sideslope, dependent upon location. Locations with a 2:1 sideslope will be stabilized with a soil retention blanket. The proposed Drainage Plan for this project more fully depicts these improvements and is contained under the "Attachment" portion of this report. 4.4 Detention Facility Outlet Structure: The detention facility outlet structure has been designed to accommodate and route collected stormwater runoff, from Drainage Basin "P2" so that during analyzed rainfall events the discharge rates are less that the ''target discharge" values. The discharge structure of the detention pond will service as the restricting orifice. Runoff will be conveyed downstream, from the pond, by means of a 48" diameter storm pipe. At the headwall of this storm drain there will only be a 42" diameter outlet which will meter flow out of the pond. Once conveyed through this restricting orifice runoff will continue to drain onto the rock rip-rap to the property line. The emergency overflow will consist of a rock rip-rap lined drainage swale. This swale will be set at an overflow elevation of 285 .10'. Should runoff, ponding in the detention facility, exceed the maximum pool elevation then it will drain across this protected swale and into the unnamed tributary of Lick Creek. 4.5 Routing Results and Conclusions: Once the project's detention facility and outlet structure was determined then the hydrograph for Drainage Basin "P2" could be routed through the detention facility and outlet structure. The routing of this hydrograph, for each analyzed rainfall event, was accomplished by means of the Hydrologic/Hydraulic stormwater modeling program HydroCAD. The program mathematically solves for continuity between the detention facilities storage capabilities, in respect to height versus storage and height versus discharge rate, with the inflow hydrograph. As shown below in Table #6 -Detention Facility Routing the designed detention facility can accommodate inflow runoff and adequately detain this stormwater so that the 198-0272 Drainage Report-Rev I Page-9 Christ United Methodist Church -Phase ill Drainage Report -Rev. No. l Rabon Metcalf Engineering May24, 2006 facility's discharge rates are minimally above the ''target" discharges without overtopping the detention system. . TABLE#6 DETENTION FACILITY ROUTING Actual Rainfall Storage Max. Discharge Target Difference Event Volume Pool Rate Discharge in Rates (vr) (cu.ft.) Depth (ft) (~fs) (cfs) (cfs) 2 41,853 282.44 60.5 52.6 7.9 5 52,303 283.09 70.8 64.4 6.4 10 60,024 283.55 77.5 72.5 5.0 25 70,533 284.15 85.5 82.9 2.6 50 82,196 284.81 93.3 93.9 -0.6 100 86,693 285.06 96.l 98.0 -1.9 Additionally, the stormwater modeling program, HydroCAD, will provide discharge attributes of the detention facilities outlet structure. The discharge of the detention pond outlet structure will be lined with rock rip-rap so that discharge velocities will be attenuated. This information is summarized below in Table #7 -Detention Facility Outlet Structure. Both the outlet structure and detention facility routing data is complied and provided in the Hydrologic/Hydraulic Modeling Using HydroCAD section contained in the "Attachment" section. TABLE#7 DETENTION FACILITY OUTLET STRUCTURE Atenuated Rainfall Actual Discharge Event Discharge Velocity (yr) Rates (cfs) (fps) 2 60.5 4.4 5 70.8 4.6 10 77.5 4.8 25 85 .5 4.9 50 93.3 5.0 100 96.1 5.1 198-0272 Drainage Report-Rev 1 Page -10 Christ United Methodist Church -Phase ill Drainage Report -Rev. No. I 5.0 CERTIFICATION Rabon Metcalf Engineering May24, 2006 "I hereby certify that this Drainage Report for the drainage design of the Christ Untied Methodist Church (4203 State Highway No. 6, South, College Station, TX) was prepared by me, or under by supervision, in accordance with the provisions of the City of College Station -Drainage Policy and Design Standards for the owners thereof." Rabon Metcalf, P. . Stat of Texas P.E. No. 88583 198-0272 Drainage Report-Rev I Page-11 VICINITY MAP PROJECT SITE: CHRIST UNITED METHODIST CHURCH 4201 STATE HIGHWAY 6, SOUTH COLLEGE STATION, TX 77845 VICINITY MAP NOT-TO-SCALE LICK CREEK DRAINAGE BASIN ' ' ' .ROCK --~ -- FIGURE II -3 LICK CREEK DRAINAGE BASIN 0 -. ····-·· - ,..., \ \ \ ' t ' ' ' \ \ ' ,. ' ' ' ,, ' / .. v- \ FEMAPANEL Raf a ranee Mark BM 53 Ill ,. RM78 l!levation (Paet NGVl>) 280.04 244.37 313.82 l>eecription of Location Proa State Route 6 and Green• Pwai load, appro:dute17 2.5 mil•• on G Prairie load to tba inter1action o Prairie load; wait approximatal7 O to mo11U11ent on left aide of road. Cbl.1"1..i 1qaara OD tlla 1011th aut ab-..c wall of Gr-ttairte load briclp Oftr Lick Craak. 8.M. AC.17, A lllf!dltd Colpa of Enainem monumontwtlhbronndllk~"M-171972' 2.1 !Mt Wiit of tho-ot ....-of S-HlthW Southbound tralflo ._... bridea over SWa High 507. M"'1c« It 2.7 faot Nonh of -fllHIP end !atSoulll-•f SoWlwutondof ~, 204.57 T8M aplk1, lltvlllon on IOp of R•-aplkl It centerline of foicflta Drivo·o-tho ....wnna of 1 72· culvln. 0 APPllOKIMATE SCAl.l eooeea5=i::::sea:s:::sea=i:o=========1':>°FEET I "" 11u1111L nuuu 111,U11111lit r1u111111• 1 FLOOD INSURANCE RATE MAP BRAZOS COUNTY, TEXAS AND INCORPORATED AREAS 1111 MA• INDEX ,011 •ANI ... NOT •AINTEDI l!lllHI mil. lllI!! COLLEGE STATION. CITY OF qQQ83 0201 0 UNINCOAPOAATED AllEAS 411191 0201 0 MAP HUMBER 48041C0201 D MAP REVISED: FEBRUARY 9, 2000 HYDROLOGIC/HYDRUALIC MODELING USING HYDROCAD x Drainage Area "X" P1 P2 Drainage Area "P1" rea "P2" Discharge Channel 8 [Reach[ Drainage Diagram for CUMC H&H-Rev 1 Prepared by {enter your company name here} 5/25/2006 HydroCAD® 7.10 sin 003394 © 2005 HydroCAD Software Solutions LLC CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 2-Year Duration=13 min, lnten=5.59 in/hr Prepared by {enter your company name here} Page 2 HydroCAD® 7 .10 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Time span=0.00-3.00 hrs, dt=0.01 hrs, 301 points Runoff by Rational method, Rise/Fa11=1 .0/2.0 xTc Reach routing by Stor-lnd+ Trans method -Pond routing by Stor-lnd method Subcatchment P1: Drainage Area "P1" Subcatchment P2: Drainage Area "P2" Subcatchment X: Drainage Area "X" Runoff Area=2.250 ac Runoff Depth=0.80" Tc=10.0 min C=0.48 Runoff=6.08 cfs 0.151 af Runoff Area=22.570 ac Runoff Depth=1 .38" Tc=12.9 min C=0.76 Runoff=95.91 cfs 2.589 af Runoff Area=24.820 ac Runoff Depth=0.77" Tc=16.9 min C=0.55 Runoff=58.71 cfs 1.589 af Reach 1 R: Discharge Channel Peak Depth=1.28' Max Vel=4.4 fps lnflow=60.45 cfs 2.588 af n=0.030 L=10.0' S=0.0100 '/' Capacity=157.29 cfs Outflow=60.45 cfs 2.588 af Pond 1 P: Detention Pond Peak Elev=282.44' Storage=41 ,853 cf lnflow=95.91 cfs 2.589 af Primary=60.45 cfs 2.588 af Secondary=0.00 cfs 0.000 af Outflow=60.45 cfs 2.588 af Total Runoff Area= 49.640 ac Runoff Volume= 4.328 af Average Runoff Depth= 1.05" CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 2-Year Duration=13 min, lnten=5.59 in/hr Prepared by {enter your company name here} Page 3 HydroCAD® 7 .10 sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Subcatchment P1: Drainage Area "P1" Runoff = 6.08 cfs @ 0.17 hrs, Volume= 0.151 af, Depth= 0.80" Runoff by Rational method, Rise/Fa11=1 .0/2.0 xTc, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs TX-Brazos County 2-Year Duration=13 min , lnten=5.59 in/hr Area (ac) C 2.250 0.48 Tc Length (min) (feet) 10.0 6 5 i 4 2 Description Post-Development conditions with M.D.W. Centre Slope Velocity Capacity Description (ft/ft) (ft/sec) ( cfs) Direct Entry, Proposed Conditions Subcatchment P1: Drainage Area "P1" Hydrograph TX-Brazos County 2-Year Duration=13 min, lnten=5.59 in/hr Runoff Area=2.250 ac Runoff Volume=0.151 af Runoff Depth=0.80" Tc=10.0 min C=0.48 Time (hours) I-Runoff~ 3 CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 2-Year Duration=13 min, lnten=5.59 in/hr Prepared by {enter your company name here} Page 4 HydroCAD® 7 .10 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Subcatchment P2: Drainage Area "P2" Runoff = 95.91 cfs @ 0.22 hrs, Volume= 2.589 af, Depth= 1.38" Runoff by Rational method, Rise/Fall=1.0/2.0 xTc, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs TX-Brazos County 2-Year Duration=13 min, lnten=5.59 in/hr Area (ac) C 22.570 0.76 Tc Length (min) (feet) 12.9 5~ Description Proposed drainage conditions to Detention Facility Slope Velocity Capacity Description (ft/ft) (ft/sec) (cfs) Direct Entry, Proposed conditions Subcatchment P2: Drainage Area "P2" Hydrograph TX-Brazos County 2-Year Duration=13 min, lnten=S.59 in/hr Runoff Area=22.570 ac Runoff Volume=2.589 af Runoff Depth=1.38" Tc=12.9 min C=0.76 0-"------------'-----------------------------....... --....... ------------1 0 2 3 Time (hours) I-Runoff. CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 2-Year Duration=13 min, lnten=5.59 in/hr Prepared by {enter your company name here} Page 5 HydroCAD® 7 .1 O s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Subcatchment X: Drainage Area "X" [48] Hint: Peak<CiA due to short duration Runoff = 58.71 cfs@ 0.22 hrs, Volume= 1.589 af, Depth= O. 77" Runoff by Rational method, Rise/Fall=1 .0/2.0 xTc, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs TX-Brazos County 2-Year Duration=13 min, lnten=5.59 in/hr Area (ac) C 24.820 0.55 Tc Length (min) (feet) 16.9 65 55 50 45 40 .f ~ 35- :c .2 30 LL. 25 20 15 10 5 Description Project Site Pre-Development Conditions Slope Velocity Capacity Description (ft/ft) (ft/sec) ( cfs) Direct Entry, Existing Conditions Subcatchment X: Drainage Area "X" Hydrograph TX-Brazos County 2-Year Duration=13 min, lnten=5.59 in/hr Runoff Area=24.820 ac Runoff Volume=1.589 af Runoff Depth=O. 77" Tc=16.9 min C=0.55 O-t-----...----...----.----..----._..-----------.------.-----.....-----...-----...---.-------..---------------1 0 2 3 Time (hours) I-Runoff~ CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 2-Year Duration=13 min, lnten=5.59 in/hr Prepared by {enter your company name here} Page 6 HydroCAD® 7 .10 sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Reach 1 R: Discharge Channel [79] Warning: Submerged Pond 1 P Primary device # 2 by 1.28' Inflow Area = Inflow = 22.570 ac, Inflow Depth > 1.38" 60.45 cfs @ 0.38 hrs, Volume= for 2-Year event 2.588 af Outflow = 60.45 cfs @ 0.38 hrs, Volume= 2.588 af, Atten= 0%, Lag= 0.1 min Routing by Star-Ind+ Trans method, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs Max. Velocity= 4.4 fps, Min. Travel Time= 0.0 min Avg. Velocity= 1.7 fps, Avg. Travel Time= 0.1 min Peak Depth= 1.28' @ 0.38 hrs Capacity at bank full= 157.29 cfs Inlet Invert= 279.00', Outlet Invert= 278.90' 20.00' x 2.00' deep Parabolic Channel, n= 0.030 Rubble masonry, cemented Length= 10.0' Slope= 0.0100 '/' 65 60- 55 50 45 40 -.;-~ 35 ~ 30 25 20 15 10 5 Reach 1 R: Discharge Channel Hydrograph Inflow Area=22.570 ac Peak Depth=1.28' Max Vel=4.4 fps n=0.030 L=10.0' S=0.0100 '/' Capacity=157 .29 cfs 2 Time (hours) 3 -Inflow -Outflow CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 2-Year Duration=13 min, lnten=5.59 in/hr Prepared by {enter your company name here} Page 7 HydroCAD® 7 .10 sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 .t::. Q. .. c '' 20 40 60 Reach 1 R: Discharge Channel Stage-Storage I -storage~ 80 100 120 140 160 180 200 220 240 260 Storage (cubic-feet) CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 2-Year Duration=13 min, lnten=5.59 in/hr Prepared by {enter your company name here} Page 8 HydroCAD® 7 .10 sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Pond 1 P: Detention Pond Inflow Area = 22.570 ac, Inflow Depth = 1.38" for 2-Year event 2.589 af Inflow = Outflow = Primary = Secondary= 95.91 cfs @ 0.22 hrs, Volume= 60.45 cfs @ 0.38 hrs, Volume= 60.45 cfs @ 0.38 hrs, Volume= 0.00 cfs @ 0.00 hrs, Volume= 2.588 af, Atten= 37%, Lag= 9.5 min 2.588 af 0.000 af Routing by Ster-Ind method, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs Peak Elev= 282.44' @ 0.38 hrs Surf.Area= 15, 704 sf Storage= 41 ,853 cf Plug-Flow detention time= 12.7 min calculated for 2.588 af (100% of inflow) Center-of-Mass det. time= 12.7 min ( 29.9 -17.2) Volume #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 #13 Invert 279.00' 279.25' 283.02' 279.35' 280.75' 283.43' 279.68' 280.42' 281.16' 282.27' 282.27' 282.27' 279.60' Avail.Storage Storage Description 89,769 cf Custom Stage Data -Pond (Prismatic) Listed below (Recalc) 3,394 cf 42.0"D x 352.74'L Horizontal Cylinder -System "A" S= 0.0090 '/' 1,414 cf 36.0"D x 200.05'L Horizontal Cylinder-System "A" S= 0.0090 '/' 227 cf 30.0"D x 46.33'L Horizontal Cylinder-System "B" S= 0.0195 '/' 348 cf 24.0"D x 110.86'L Horizontal Cylinder-System "B" S= 0.0195 '/' 101 cf 18.0"D x 57.18'L Horizontal Cylinder-System "B" S= 0.0050 '/' 334 cf 36.0"D x 47.19'L Horizontal Cylinder-System "C" S= 0.0050 '/' 697 cf 24.0"D x 221. 72'L Horizontal Cylinder-System "C" S= 0.0030 '/' 78 cf 18.0"D x 43.91'L Horizontal Cylinder-System "C" S= 0.0100 '/' 375 cf 18.0"D x 212.46'L Horizontal Cylinder-System "C" S= 0.0050 '/' 212 cf 18.0"D x 120.00'L Horizontal Cylinder-System "C" S= 0.0100 '/' 318 cf 18.0"D x 180.00'L Horizontal Cylinder-System "C" S= 0.0100 '/' 45 cf 18.0"D x 25.50'L Horizontal Cylinder-System "D" S= 0.0100 '/' 97,312 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet} (sg-ft} 279.00 0 279.50 10,780 280.00 11 ,261 281.00 12,375 282.00 13,482 283.00 14,742 284.00 16,047 285.10 17,463 285.60 18,057 Device Routing Invert #1 Secondary 285.1 O' #2 Primary 279.00' (cubic-feet} (cubic-feet} 0 0 2,695 2,695 5,510 8,205 11,818 20,023 12,929 32,952 14,112 47,064 15,395 62,458 18,431 80,889 8,880 89,769 Outlet Devices 6.0' long x 10.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64 42.0" Vert. Orifice/Grate C= 0.600 CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 2-Year Duration=13 min, lnten=5.59 in/hr Prepared by {enter your company name here} Page 9 HydroCAD® 7 .1 O sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Primary OutFlow Max=60.45 cfs@ 0.38 hrs HW=282.43' (Free Discharge) L2=0rifice/Grate (Orifice Controls 60.45 cfs@ 6.3 fps) t:_condary OutFlow Max=0.00 cfs @ 0.00 hrs HW=279.00' (Free Discharge) 1=Broad-Crested Rectangular Weir (Controls 0.00 cfs) 105 100 · 95 ' 90 85. 80 75 70 65 ~ 60 ~ 55 ~ 50 0 ii: 45 40 35 30 25 : 20 10~ Pond 1 P: Detention Pond Hydrograph Inflow Area=22.570 ac Peak Elev=282.44' · Storage=41,853 cf ' 2 Time (hours) -Inflow -Outflow -Primary -Secondary 3 CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 2-Year Duration=13 min, lnten=5.59 in/hr Prepared by {enter your company name here} Page 10 HydroCAD® 7 .10 sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Pond 1 P: Detention Pond Stage-Area-Storage I-Storage~ 287- 286 285- ! 284- c 0 ~ 283 > Cl> ii.i 282- 281 280 279 ' 0 10,000 20,000 30,000 40,000 50,000 60,000 70,000 80,000 90,000 Storage (cubic-feet) CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 5-Year Duration=13 min, lnten=6.84 in/hr Prepared by {enter your company name here} Page 11 HydroCAD® 7 .10 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Time span=0.00-3.00 hrs, dt=0.01 hrs, 301 points Runoff by Rational method, Rise/Fall=1.0/2.0 xTc Reach routing by Stor-lnd+ Trans method -Pond routing by Stor-lnd method Subcatchment P1: Drainage Area "P1" Subcatchment P2: Drainage Area "P2" Subcatchment X: Drainage Area "X" Runoff Area=2.250 ac Runoff Depth=0.98" Tc=10.0 min C=0.48 Runoff=7.45 cfs 0.185 af Runoff Area=22.570 ac Runoff Depth=1 .68" Tc=12.9 min C=0.76 Runoff=117.36 cfs 3.167 af Runoff Area=24.820 ac Runoff Depth=0.94" Tc=16.9 min C=0.55 Runoff=71.83 cfs 1.944 af Reach 1 R: Discharge Channel Peak Depth=1 .38' Max Vel=4.6 fps lnflow=70.84 cfs 3.167 af n=0.030 L=10.0' S=0 .0100 '/' Capacity=157.29 cfs Outflow=70.84 cfs 3.167 af Pond 1 P: Detention Pond Peak Elev=283.09' Storage=52,303 cf lnflow=117.36 cfs 3.167 af Primary=70.84 cfs 3.167 af Secondary=0.00 cfs 0.000 af Outflow=70.84 cfs 3.167 af Total Runoff Area= 49.640 ac Runoff Volume= 5.296 af Average Runoff Depth= 1.28" CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 5-Year Duration=13 min, lnten=6.84 in/hr Prepared by {enter your company name here} Page 12 HydroCAD® 7 .10 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Subcatchment P1: Drainage Area "P1" Runoff = 7.45 cfs @ 0.17 hrs, Volume= 0.185af, Depth= 0.98" Runoff by Rational method, Rise/Fall=1.0/2.0 xTc, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs TX-Brazos County 5-Year Duration=13 min, lnten=6.84 in/hr Area (ac) C 2.250 0.48 Tc Length (min) (feet) 10.0 8 7 6 5 3- 2- Description Post-Development conditions with M.D.W. Centre Slope Velocity Capacity Description (ft/ft) (ft/sec) (cfs) Direct Entry, Proposed Conditions Subcatchment P1: Drainage Area "P1" Hydrograph TX-Brazos County 5-Year Duration=13 min, lnten=6.84 in/hr Runoff Area=2.250 ac Runoff Volume=0.185 af Runoff Depth=0.98" Tc=10.0 min C=0.48 O-'------------...a...--------------------.---------.,......---..---.----.----.---------~ 0 2 3 Time (hours) I-Runoff I CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 5-Year Duration=13 min, lnten=6.84 in/hr Prepared by {enter your company name here} Page 13 Hydro CAD® 7 .10 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Subcatchment P2: Drainage Area "P2" Runoff = 117.36 cfs@ 0.22 hrs, Volume= 3.167 af, Depth= 1. 68" Runoff by Rational method, Rise/Fall=1.0/2.0 xTc, Time Span= 0.00-3 .00 hrs, dt= 0.01 hrs TX-Brazos County 5-Year Duration=13 min, lnten=6.84 in/hr Area (ac) C 22.570 0.76 Tc Length (min) (feet) 12.9 130 125 120 115 110 . 10s~ 100 951 90 as ; 80 . ~ 75 .e ~ 0 U:: 40 35 30 25 20 15 : 1 0~ s1 0 0 Description Proposed drainage conditions to Detention Facility Slope Velocity Capacity Description (tuft) (fUsec) ( cfs) Direct Entry, Proposed conditions Subcatchment P2: Drainage Area "P2" Hydrograph TX-Brazos County 5-Year Duration=13 min, lnten=6.84 in/hr Runoff Area=22.570 ac Runoff Volume=3.167 af Runoff Depth=1.68" Tc=12.9 min C=0.76 2 Time (hours) I-Runoff I 3 CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 5-Year Duration=13 min, lnten=6.84 in/hr Prepared by {enter your company name here} Page 14 HydroCAD® 7 .10 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Subcatchment X: Drainage Area "X" [48] Hint: Peak<CiA due to short duration Runoff = 71.83 cfs @ 0.22 hrs, Volume= 1.944 af, Depth= 0.94" Runoff by Rational method, Rise/Fall=1.0/2.0 xTc, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs TX-Brazos County 5-Year Duration=13 min, lnten=6.84 in/hr Area (ac) C Description 24.820 0.55 Project Site Pre-Development Conditions Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) ( cfs) 16.9 Direct Entry, Existing Conditions Subcatchment X: Drainage Area "X" Hydrograph ao---~~~~~~~~~~~~~~~~~~~~~~~~~~--, 75~ 70~ 65 so~ 55 . so : 30 . 25- 20 15 10 5 TX-Brazos County 5-Year Duration=13 min, lnten=6.84 in/hr Runoff Area=24.820 ac Runoff Volume=1.944 af Runoff Depth=0.94" Tc=16.9 min C=0.55 0-+---------------..----.---------------..----------------..--....... --...., 0 2 3 Time (hours) I-Runoff. CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 5-Year Duration=13 min, lnten=6.84 in/hr Prepared by {enter your company name here} Page 15 HydroCAD® 7 .10 sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Reach 1 R: Discharge Channel [79] Warning: Submerged Pond 1 P Primary device # 2 by 1.38' Inflow Area= Inflow = 22.570 ac, Inflow Depth > 1.68" 70.84 cfs @ 0.39 hrs, Volume= for 5-Year event 3.167 af Outflow = 70.84 cfs @ 0.39 hrs, Volume= 3.167 af, Atten= 0%, Lag= 0.1 min Routing by Ster-Ind+ Trans method, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs Max. Velocity= 4.6 fps, Min . Travel Time= 0.0 min Avg. Velocity= 1.8 fps, Avg. Travel Time= 0.1 min Peak Depth= 1.38' @ 0.39 hrs Capacity at bank full= 157.29 cfs Inlet Invert= 279.00', Outlet Invert= 278.90' 20.00' x 2.00' deep Parabolic Channel, n= 0.030 Rubble masonry, cemented Length= 10.0' Slope= 0.0100 '/' Reach 1 R: Discharge Channel Hydrograph 75 70 65 -Inflow Area=22.570 ac 60 Peak Depth=1.38' 55 _ 50 Max Vel=4.6 fps ;f' 45 n=0.030 (J ; 40 L=10.0' 0 u:: 35 _ 30 S=0.0100 '/' 25· 20 Capacity=157 .29 cfs 5 o-lL--.----------------~---......:==:=:=:;::===1111--,.... __ ------------....--.J 0 2 3 Time (hours) -Inflow -Outflow CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 5-Year Duration=13 min, lnten=6.84 in/hr Prepared by {enter your company name here} Page 16 HydroCAD® 7 .1 O sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 ! Reach 1 R: Discharge Channel Stage-Storage .r: 1- Q. Cl> c o-J-.-.,.......,..._.,.....,......,........,_... ...... .,......_...,... ....... .....,...,...........,~ ...... .,......,......,...,. ...... ....,.. ...... ,.....,....,..,....,..........,..,...,...... 0 20 40 60 80 100 120 140 160 180 200 220 240 260 Storage (cubic-feet) I-Storage~ CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 5-Year Duration=13 min, lnten=6.84 in/hr Prepared by {enter your company name here} Page 17 HydroCAD® 7 .1 O sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Pond 1 P: Detention Pond Inflow Area = 22.570 ac, Inflow Depth = 1.68" for 5-Year event 3.167 af Inflow = Outflow = Primary = Secondary= 117.36 cfs @ 0.22 hrs, Volume= 70.84 cfs @ 0.39 hrs, Volume= 70.84 cfs @ 0.39 hrs, Volume= 0.00 cfs @ 0.00 hrs, Volume= 3.167 af, Atten= 40%, Lag= 10.2 min 3.167 af 0.000 af Routing by Stor-l nd method, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs Peak Elev= 283.09'@ 0.39 hrs Surf.Area= 16,339 sf Storage= 52,303 cf Plug-Flow detention time= 12.5 min calculated for 3.156 af (100% of inflow) Center-of-Mass det. time= 12.8 min ( 30 .0 -17.2) Volume #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 #13 Elevation (feet) 279.00 279.50 280.00 281.00 282.00 283.00 284.00 285.10 285.60 Invert Avail.Storage Storage Description 279.00' 279.25' 283.02' 279.35' 280.75' 283.43' 279.68' 280.42' 281.16' 282.27' 282.27' 282.27' 279.60' Surf.Area (sq-ft) 0 10,780 11 ,261 12,375 13,482 14,742 16,047 17,463 18,057 89,769 cf Custom Stage Data -Pond (Prismatic) Listed below (Recalc) 3,394 cf 42.0"D x 352.74'L Horizontal Cylinder -System "A" S= 0.0090 '/' 1,414 cf 36.0"D x 200.05'L Horizontal Cylinder-System "A" S= 0.0090 '/' 227 cf 30.0"D x 46.33'L Horizontal Cylinder-System "B" S= 0.0195 '/' 348 cf 24.0"D x 110.86'L Horizontal Cylinder-System "B" S= 0.0195 '/' 101 cf 18.0"D x 57.18'L Horizontal Cylinder-System "B" S= 0.0050 '/' 334 cf 36.0"D x 47.19'L Horizontal Cylinder-System "C" S= 0.0050 '/' 697 cf 24.0"D x 221.72'L Horizontal Cylinder-System "C" S= 0.0030 '/' 78 cf 18.0"D x 43.91 'L Horizontal Cylinder-System "C" S= 0.0100 '/' 375 cf 18.0"D x 212.46'L Horizontal Cylinder-System "C" S= 0.0050 '/' 212 cf 18.0"D x 120.00'L Horizontal Cylinder-System "C" S= 0.0100 '/' 318 cf 18.0"D x 180.00'L Horizontal Cylinder-System "C" S= 0.0100 '/' 45 cf 18.0"D x 25.50'L Horizontal Cylinder-System "D" S= 0.0100 '/' 97,312 cf Total Available Storage Inc.Store (cubic-feet) 0 2,695 5,510 11 ,818 12,929 14,112 15,395 18,431 8,880 Cum.Store (cubic-feet) 0 2,695 8,205 20,023 32,952 47,064 62,458 80,889 89,769 Device Routing Invert Outlet Devices #1 Secondary 285.10' 6.0' long x 10.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64 #2 Primary 279.00' 42.0" Vert. Orifice/Grate C= 0.600 CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 5-Year Duration=13 min, lnten=6.84 in/hr Prepared by {enter your company name here} Page 18 HydroCAD® 7.10 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Primary OutFlow Max=70.84 cfs@ 0.39 hrs HW=283.09' (Free Discharge) L2=0rifice/Grate (Orifice Controls 70.84 cfS@ 7.4 fps) Secondary OutFlow Max=0.00 cfs@ 0.00 hrs HW=279.00' (Free Discharge) L1=Broad-Crested Rectangular Weir (Controls 0.00 cfs) . 130 125 120 115 11 0. 105 100 . 95 90 85 80- ¥!. 75 .e. 70 3:: 65 0 60 ii: 55 so: 45 40 35 30-' 25 20 15 0 , 0 Pond 1 P: Detention Pond Hydrograph Inflow Area=22.570 ac Peak Elev=283.09' Storage=52,303 cf 2 Time (hours) -Inflow -Outflow -Primary -Secondary 3 CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 5-Year Duration=13 min, lnten=6.84 in/hr Prepared by {enter your company name here} Page 19 HydroCAD® 7 .10 sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Pond 1 P: Detention Pond Stage-Area-Storage 287 I-Storage j 286 285- 282- 281- 280 279...,_, __ ' 0 10,000 20,000 30,000 40,000 50,000 60,000 70,000 80,000 90,000 Storage (cubic-feet) CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 10-Year Duration=13 min, lnten=7. 70 in/hr Prepared by {enter your company name here} Page 20 HydroCAD® 7 .10 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Time span=0.00-3.00 hrs, dt=0.01 hrs, 301 points Runoff by Rational method, Rise/Fall=1 .0/2.0 xTc Reach routing by Ster-Ind+ Trans method -Pond routing by Ster-Ind method Subcatchment P1: Drainage Area "P1" Subcatchment P2: Drainage Area "P2" Subcatchment X: Drainage Area "X" Runoff Area=2.250 ac Runoff Depth=1 .11" Tc=10.0 min C=0.48 Runoff=8.38 cfs 0.208 af Runoff Area=22.570 ac Runoff Depth=1 .90" Tc=12.9 min C=0.76 Runoff=132.16 cfs 3.567 af Runoff Area=24.820 ac Runoff Depth=1 .06" Tc=16.9 min C=0.55 Runoff=80.89 cfs 2.189 af Reach 1R: Discharge Channel Peak Depth=1.44' Max Vel=4.8 fps lnflow=77.52 cfs 3.566 af n=0 .030 L=10.0' S=0.0100 '/' Capacity=157.29 cfs Outflow=77.52 cfs 3.566 af Pond 1 P: Detention Pond Peak Elev=283.55' Storage=60,024 cf lnflow=132.16 cfs 3.567 af Primary=77.52 cfs 3.566 af Secondary=0.00 cfs 0.000 af Outflow=77.52 cfs 3.566 af Total Runoff Area= 49.640 ac Runoff Volume= 5.964 af Average Runoff Depth= 1.44" CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 10-Year Duration=13 min, lnten=l.70 in/hr Prepared by {enter your company name here} Page 21 HydroCAD® 7 .1 O sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Subcatchment P1: Drainage Area "P1" Runoff = 8.38 cfs @ 0.17 hrs, Volume= 0.208 af, Depth= 1.11" Runoff by Rational method, Rise/Fall=1 .0/2.0 xTc, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs TX-Brazos County 10-Year Duration=13 min, lnten=7.70 in/hr Area (ac) C 2.250 0.48 Tc Length (min) (feet) 10.0 9 8- 7- 6 3 2 Description Post-Development conditions with M.D.W. Centre Slope Velocity Capacity Description (ft/ft) (ft/sec) (cfs) Direct Entry, Proposed Conditions Subcatchment P1: Drainage Area "P1" Hydrograph TX-Brazos County 10-Year Duration=13 min, lnten=7.70 in/hr Runoff Area=2.250 ac Runoff Volume=0.208 af Runoff Depth=1.11" Tc=10.0 min C=0.48 0-f---...------...------"""T'"---.-------...---..-------.----------....... --~ 0 2 3 Time (hours) I-Runoff~ CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 10-Year Duration=13 min, lnten=l.70 in/hr Prepared by {enter your company name here} Page 22 HydroCAD® 7 .10 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Subcatchment P2: Drainage Area "P2" Runoff = 132.16 cfs @ 0.22 hrs, Volume= 3.567 af, Depth= 1.90" Runoff by Rational method, Rise/Fall=1.0/2.0 xTc, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs TX-Brazos County 10-Year Duration=13 min , lnten=?.70 in/hr Area (ac) C 22.570 0.76 Tc Length (min) (feet) 12.9 140 130 120 110 100 90 $. 80 .e ~ 70 0 u: 60 50 Description Proposed drainage conditions to Detention Facility Slope Velocity Capacity Description (ft/ft) (ft/sec) (cfs) Direct Entry, Proposed conditions Subcatchment P2: Drainage Area "P2" Hydrograph TX-Brazos County 10-Year Duration=13 min, lnten=7.70 in/hr Runoff Area=22.570 ac Runoff Volume=3.567 af Runoff Depth=1.90" Tc=12.9 min C=0.76 2 Time (hours) I-Runoff~ 3 CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 10-Year Duration=13 min, lnten=l.70 in/hr Prepared by {enter your company name here} Page 23 HydroCAD® 7 .10 sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Subcatchment X: Drainage Area "X" (48] Hint: Peak<CiA d_ue to short duration Runoff = 80.89 cfs @ 0.22 hrs, Volume= 2.189 at, Depth= 1.06" Runoff by Rational method, Rise/Fall=1.0/2.0 xTc, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs TX-Brazos County 10-Year Duration=13 min, lnten=?.70 in/hr Area (ac) C 24.820 0.55 Tc Length (min) (feet) 16.9 Description Project Site Pre-Development Conditions Slope Velocity Capacity Description (ft/ft) (ft/sec) ( cfs) Direct Entry, Existing Conditions Subcatchment X: Drainage Area "X" Hydrograph 90-----------------------------~ as~ 80 75 · 70 65 :f' 50: ~ . 3:: 45. 0 . ii: 40 35 30 25 ' 20 15. 10 5- TX-Brazos County 10-Year Duration=13 min, lnten=7. 70 in/hr Runoff Area=24.820 ac Runoff Volume=2.189 af Runoff Depth=1.06" Tc=16.9 min C=0.55 0-+---..----,____,_.___,, ______________________ ...-__ ,____, __ __,, __ _,.. __ ~ 0 2 3 Time (hours) I-Runoff I CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 10-Year Duration=13 min, lnten=l.70 in/hr Prepared by {enter your company name here} Page 24 HydroCAD® 7 .1 O sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Reach 1 R: Discharge Channel [79) Warning: Submerged Pond 1 P Primary device # 2 by 1.44' Inflow Area= 22.570 ac, Inflow Depth> 1.90" for 10-Year event Inflow = 77.52 cfs @ 0.40 hrs, Volume= 3.566 af Outflow = 77.52 cfs @ 0.40 hrs, Volume= 3.566 af, Atten= 0%, Lag= 0.1 min Routing by Ster-Ind+ Trans method, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs Max. Velocity= 4.8 fps, Min. Travel Time= 0.0 min Avg . Velocity = 1.9 fps, Avg. Travel Time= 0.1 min Peak Depth= 1.44' @ 0.40 hrs Capacity at bank full= 157.29 cfs Inlet Invert= 279.00', Outlet Invert= 278.90' 20.00' x 2.00' deep Parabolic Channel, n= 0.030 Rubble masonry, cemented Length= 10.0' Slope= 0.0100 '/' Reach 1 R: Discharge Channel Hydrograph 85 80~ 77.52 cfs 75 Inflow Area=22.570 ac 70 65 Peak Depth=1.44' 60 55 Max Vel=4.8 fps i' 50 n=0.030 ~ 45 ~ 40 L=10.0' LL 35 S=0.0100 '/' 30 25 . Capacity=157 .29 cfs 20 15 ' 2 Time (hours) -Inflow -Outflow 3 CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 10-Year Duration=13 min, lnten=l.70 in/hr Prepared by {enter your company name here} Page 25 HydroCAD® 7 .1 0 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 .:: Q. .. 0 20 40 60 Reach 1 R: Discharge Channel Stage-Storage I-Storagel 80 100 120 140 160 180 200 220 240 260 Storage (cubic-feet) CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 10-Year Duration=13 min, lnten=l. 70 in/hr Prepared by {enter your company name here} Page 26 HydroCAD® 7 .10 sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Pond 1 P: Detention Pond Inflow Area = 22.570 ac, Inflow Depth= 1.90" for 10-Year event 3.567 at Inflow = 132.16 cfs @ 0.22 hrs, Volume= Outflow = 77.52 cfs@ 0.40 hrs, Volume= Primary = 77.52 cfs @ 0.40 hrs, Volume= Secondary= 0.00 cfs @ 0.00 hrs, Volume= 3.566 af, Atten= 41%, Lag= 10.6 min 3.566 af 0.000 af Routing by Stor-lnd method, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs Peak Elev= 283.55'@ 0.40 hrs Surf.Area= 17,064 sf Storage= 60,024 cf Plug-Flow detention time= 12.7 min calculated for 3.554 af (100% of inflow) Center-of-Mass det. time= 12.9 min ( 30.2 -17.2) Volume #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 #13 Invert 279.00' 279.25' 283.02' 279.35' 280.75' 283.43' 279.68' 280.42' 281 .16' 282.27' 282.27' 282.27' 279.60' Avail.Storage Storage Description 89,769 cf Custom Stage Data -Pond (Prismatic) Listed below (Recalc) 3,394 cf 42.0"D x 352.74'L Horizontal Cylinder -System "A" S= 0.0090 '/' 1,414 cf 36.0"D x 200.05'L Horizontal Cylinder-System "A" S= 0.0090 '/' 227 cf 30.0"D x 46.33'L Horizontal Cylinder-System "B" S= 0.0195 '/' 348 cf 24.0"D x 110.86'L Horizontal Cylinder-System "B" S= 0.0195 '/' 101 cf 18.0"D x 57.18'L Horizontal Cylinder-System "B" S= 0.0050 '/' 334 cf 36.0"D x 47.19'L Horizontal Cylinder-System "C" S= 0.0050 '/' 697 cf 24.0"D x 221.72'L Horizontal Cylinder-System "C" S= 0.0030 '/' 78 cf 18.0"D x 43.91'L Horizontal Cylinder-System "C" S= 0.0100 '/' 375 cf 18.0"D x 212.46'L Horizontal Cylinder-System "C" S= 0.0050 '/' 212 cf 18.0"D x 120.00'L Horizontal Cylinder-System "C" S= 0.0100 '/' 318 cf 18.0"D x 180.00'L Horizontal Cylinder-System "C" S= 0.0100 '/' 45 cf 18.0"D x 25.50'L Horizontal Cylinder-System "D" S= 0.0100 '/' 97,312 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store {feet} {sg-ft} 279.00 0 279.50 10,780 280.00 11 ,261 281 .00 12,375 282.00 13,482 283.00 14,742 284.00 16,047 285.1 0 17,463 285.60 18,057 Device Routing Invert #1 Secondary 285.1 O' #2 Primary 279.00' {cubic-feet} {cubic-feet} 0 0 2,695 2,695 5,510 8,205 11,818 20,023 12,929 32,952 14, 112 47,064 15,395 62,458 18,431 80,889 8,880 89,769 Outlet Devices 6.0' long x 10.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64 42.0" Vert. Orifice/Grate C= 0.600 CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 10-Year Duration=13 min, lnten=l.70 in/hr Prepared by {enter your company name here} Page 27 HydroCAD® 7 .10 sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Primary OutFlow Max=77.51 cfs @ 0.40 hrs HW=283.55' (Free Discharge) L2=0rifice/Grate (Orifice Controls 77.51 cfs@ 8.1 fps) ~condary OutFlow Max=0.00 cfs@ 0.00 hrs HW=279.00' (Free Discharge) 1=Broad-Crested Rectangular Weir (Controls 0.00 cfs) Pond 1P: Detention Pond Hydrograph Inflow Area=22.570 ac Peak Elev=283.55' Storage=60,024 cf 2 Time (hours) -Inflow -Outflow -Primary -Secondary ' 3 CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 10-Year Duration=13 min, lnten=l.70 in/hr Prepared by {enter your company name here} Page 28 HydroCAD® 7 .10 sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Pond 1 P: Detention Pond Stage-Area-Storage 287 I-Storage. 286 285- + + 282- 281 280 ' ' 10,000 20,000 30,000 40,000 50,000 60,000 70,000 80,000 90,000 Storage (cubic-feet) CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 25-Year Duration=13 min, lnten=B.81 in/hr Prepared by {enter your company name here} Page 29 HydroCAD® 7 .10 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Time span=0.00-3.00 hrs, dt=0.01 hrs, 301 points Runoff by Rational method, Rise/Fall=1 .0/2.0 xTc Reach routing by Ster-Ind+ Trans method -Pond routing by Ster-Ind method Subcatchment P1: Drainage Area "P1" Subcatchment P2: Drainage Area "P2" Subcatchment X: Drainage Area "X" Runoff Area=2.250 ac Runoff Depth=1 .27" Tc=10.0 min C=0.48 Runoff=9.59 cfs 0.238 af Runoff Area=22.570 ac Runoff Depth=2.17" Tc=12.9 min C=0.76 Runoff=151 .14 cfs 4.079 af Runoff Area=24.820 ac Runoff Depth=1 .21" Tc=16.9 min C=0.55 Runoff=92.51 cfs 2.504 af Reach 1 R: Discharge Channel Peak Depth=1 .51' Max Vel=4.9 fps lnflow=85.48 cfs 4.079 af n=0.030 L=10.0' S=0.0100 'f Capacity=157.29 cfs Outflow=85.48 cfs 4.079 af Pond 1 P: Detention Pond Peak Elev=284.15' Storage=70,533 cf lnflow=151 .14 cfs 4.079 af Primary=85.48 cfs 4.079 af Secondary=0.00 cfs 0.000 at Outflow=85.48 cfs 4.079 af Total Runoff Area= 49.640 ac Runoff Volume= 6.820 af Average Runoff Depth= 1.65" CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 25-Year Duration=13 min, lnten=B.81 in/hr Prepared by {enter your company name here} Page 30 HydroCAD® 7 .1 O sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Subcatchment P1: Drainage Area "P1" Runoff = 9.59 cfs @ 0.17 hrs, Volume= 0.238 af, Depth= 1.27" Runoff by Rational method, Rise/Fall=1 .0/2.0 xTc, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs TX-Brazos County 25-Year Duration=13 min, lnten=8.81 in/hr Area (ac) C 2.250 0.48 Tc Length (min) (feet) 10.0 10 9 8 7 4 3 2 1- Description Post-Development conditions with M.D .W. Centre Slope Velocity Capacity Description (ft/ft) (ft/sec) (cfs) Direct Entry, Proposed Conditions Subcatchment P1: Drainage Area "P1" Hydrograph TX-Brazos County 25-Year Duration=13 min, lnten=8.81 in/hr Runoff Area=2.250 ac Runoff Volume=0.238 af Runoff Depth=1.27" Tc=10.0 min C=0.48 o...,_ __ ._. __ ,,__ ....... __ ....... ______________________ ._. __ ,,_......,.--.....,.---.....----1, 0 2 3 Time (hours) I-Runottt CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 25-Year Duration=13 min, lnten=B.81 in/hr Prepared by {enter your company name here} Page 31 HydroCAD® 7 .1 O s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Subcatchment P2: Drainage Area "P2" Runoff = 151 .14 cfs@ 0.22 hrs, Volume= 4.079 af, Depth= 2.17" Runoff by Rational method , Rise/Fall=1 .0/2.0 xTc, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs TX-Brazos County 25-Year Duration=13 min, lnten=8.81 in/hr Area (ac) C 22.570 0.76 Tc Length (min) (feet) 12.9 !!. ~ ~ 0 u: 160 1 50~ 140~ 130 · 120 110 70 30 20 10 Description Proposed drainage conditions to Detention Facility Slope Velocity Capacity Description (ft/ft) (ft/sec) (cfs) Direct Entry, Proposed conditions Subcatchment P2: Drainage Area "P2" Hydrograph TX-Brazos County 25-Year Duration=13 min, lnten=S.81 in/hr Runoff Area=22.570 ac Runoff Volume=4.079 af Runoff Depth=2.17" Tc=12.9 min C=0.76 0+-----....-----..-........... --------------....-----------..------------.----...... -----..---------------1 0 2 3 Time (hours) I-Runottj CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 25-Year Duration=13 min, lnten=B.81 in/hr Prepared by {enter your company name here} Page 32 HydroCAD® 7 .10 sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Subcatchment X: Drainage Area "X" [48] Hint: Peak<CiA due to short duration Runoff = 92.51 cfs @ 0.22 hrs, Volume= 2.504 af, Depth= 1.21" Runoff by Rational method , Rise/Fa11=1 .0/2.0 xTc, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs TX-Brazos County 25-Year Duration=13 min, lnten=8.81 in/hr Area (ac) C Description 24.820 0.55 Project Site Pre-Development Conditions Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) ( cfs) 16.9 Direct Entry, Existing Conditions Subcatchment X: Drainage Area "X" Hydrograph 100 95 · 92.51 cfs 90~ TX-Brazos County 25-Year 85 ao · Duration=13 min, 75- 70 lnten=8.81 in/hr 65 . Runoff Area=24.820 ac 60 .f 55 Runoff Volume=2.504 af ~ ~ 50 0 Runoff Depth=1.21" ii: 45 40 Tc=16.9 min 35 30 C=0.55 25 20 15 10 5 2 Time (hours) 1-Runoff~ 3 CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 25-Year Duration=13 min, lnten=B.81 in/hr Prepared by {enter your company name here} Page 33 HydroCAD® 7 .1 O sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Reach 1 R: Discharge Channel [79] Warning: Submerged Pond 1 P Primary device# 2 by 1.51' Inflow Area = 22.570 ac, Inflow Depth > 2.17" for 25-Year event Inflow = 85.48 cfs @ 0.41 hrs, Volume= 4.079 af Outflow = 85.48 cfs@ 0.41 hrs, Volume= 4.079 af, Atten= 0%, Lag= 0.0 min Routing by Stor-lnd+ Trans method, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs Max. Velocity= 4.9 fps, Min. Travel Time= 0.0 min Avg. Velocity = 2.0 fps , Avg. Travel Time= 0.1 min Peak Depth= 1.51'@ 0.41 hrs Capacity at bank full= 157.29 cfs Inlet Invert= 279.00', Outlet Invert= 278.90' 20.00' x 2.00' deep Parabolic Channel, n= 0.030 Rubble masonry, cemented Length= 10.0' Slope= 0.0100 '/' 60 i' 55 ~ 50 ~ 45 Li: 40 35 30 25 Reach 1 R: Discharge Channel Hydrograph Inflow Area=22.570 ac Peak Depth=1.51' Max Vel=4.9 fps n=0.030 L=10.0' S=0.0100 '/' Capacity=157 .29 cfs 2 Time (hours) 3 -Inflow -Outflow CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 25-Year Duration=13 min, lnten=B.81 in/hr Prepared by {enter your company name here} Page 34 HydroCAD® 7 .10 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 ~ a. .. c Reach 1 R: Discharge Channel Stage-Storage I-Storage~ o .......................................... ......,, ............. .,..,.....,......,......,........,..,..,........,...,........,..,..,.....,..,..,...,. ....... ....,.. ....... ......, ............. .,.......,...,.....,_ 0 20 40 60 80 100 120 140 160 180 200 220 240 260 Storage (cubic-feet) CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 25-Year Duration=13 min, lnten=B.81 in/hr Prepared by {enter your company name here} Page 35 HydroCAD® 7 .1 O sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Pond 1 P: Detention Pond Inflow Area = 22.570 ac, Inflow Depth= 2.17" for 25-Year event 4.079 af Inflow = 151 .14 cfs@ 0.22 hrs, Volume= Outflow = 85.48 cfs @ 0.41 hrs, Volume= Primary = 85.48 cfs @ 0.41 hrs, Volume= Secondary= 0.00 cfs @ 0.00 hrs, Volume= 4.079 af, Atten= 43%, Lag= 11.2 min 4.079 af 0.000 af Routing by Ster-Ind method, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs Peak Elev= 284.15' @ 0.41 hrs Surf.Area= 17 ,626 sf Storage= 70 ,533 cf Plug-Flow detention time= 13.3 min calculated for 4.079 af (100% of inflow) Center-of-Mass det. time= 13.3 min ( 30.5-17.2) Volume #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 #13 Invert 279.00' 279.25' 283.02' 279.35' 280.75' 283.43' 279.68' 280.42' 281 .16' 282.27' 282.27' 282 .27' 279.60' Avail.Storage Storage Description 89,769 cf Custom Stage Data -Pond (Prismatic) Listed below (Recalc) 3,394 cf 42.0"D x 352.74'L Horizontal Cylinder -System "A" S= 0.0090 '/' 1,414 cf 36.0"D x 200.05'L Horizontal Cylinder-System "A" S= 0.0090 '/' 227 cf 30.0"D x 46.33'L Horizontal Cylinder-System "B" S= 0.0195 '/' 348 cf 24.0"D x 110.86'L Horizontal Cylinder-System "B" S= 0.0195 '/' 101 cf 18.0"D x 57.18'L Horizontal Cylinder-System "B" S= 0.0050 '/' 334 cf 36.0"D x 47.19'L Horizontal Cylinder-System "C" S= 0.0050 '/' 697 cf 24.0"D x 221. 72'L Horizontal Cylinder-System "C" S= 0.0030 '/' 78 cf 18.0"D x 43.91'L Horizontal Cylinder-System "C" S= 0.0100 '/' 375 cf 18.0"D x 212.46'L Horizontal Cylinder-System "C" S= 0.0050 '/' 212 cf 18.0"D x 120.00'L Horizontal Cylinder-System "C" S= 0.0100 '/' 318 cf 18.0"D x 180.00'L Horizontal Cylinder-System "C" S= 0.0100 '/' 45 cf 18.0"D x 25.50'L Horizontal Cylinder-System "D" S= 0.0100 '/' 97 ,312 cf Total Available Storage Elevation Surf.Area Inc.Store Cum .Store {feet} {sg-ft} 279.00 0 279.50 10,780 280.00 11,261 281.00 12,375 282.00 13,482 283.00 14,742 284.00 16,047 285.10 17,463 285.60 18,057 Device Routing Invert #1 Secondary 285 .1 O' #2 Primary 279.00' {cubic-feet} {cubic-feet} 0 0 2,695 2,695 5,510 8,205 11 ,818 20 ,023 12,929 32 ,952 14,112 47 ,064 15,395 62,458 18,431 80 ,889 8,880 89 ,769 Outlet Devices 6.0' long x 10.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64 42.0" Vert. Orifice/Grate C= 0.600 CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 25-Year Duration=13 min, lnten=B.81 in/hr Prepared by {enter your company name here} Page 36 HydroCAD® 7 .10 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Primary OutFlow Max=85.47 cfs@0.41 hrs HW=284.15' (Free Discharge) L2=0rifice/Grate (Orifice Controls 85.47 cfs @ 8.9 fps) t:_condary OutFlow Max=0.00 cfs@ 0.00 hrs HW=279.00' (Free Discharge) 1=Broad-Crested Rectangular Weir (Controls 0.00 cfs) 160- 140 120 110 100 ~ 90 .!:!.. ~ 80 . 0 ii: 70 60- 50- 40- 30 Pond 1 P: Detention Pond Hydrograph Inflow Area=22.570 ac Peak Elev=284.15' Storage=70,533 cf 2 Time (hours) -·Inflow -Outflow -Primary -Secondary ' 3 CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 25-Year Duration=13 min, lnten=B.81 in/hr Prepared by {enter your company name here} Page 37 HydroCAD® 7 .10 sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Pond 1 P: Detention Pond Stage-Area-Storage 287 I -storage~ 286 285 I 284 c: 0 :; 283 > .. iii 282- 281 280 10,000 20,000 40,000 50,000 60,000 70,000 80,000 90,000 Storage (cubic-feet) CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 50-Year Duration=13 min, lnten=9.97 in/hr Prepared by {enter your company name here} Page 38 HydroCAD® 7 .10 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Time span=0.00-3.00 hrs, dt=0.01 hrs, 301 points Runoff by Rational method, Rise/Fall=1 .0/2.0 xTc Reach routing by Star-Ind+ Trans method -Pond routing by Star-Ind method Subcatchment P1: Drainage Area "P1" Subcatchment P2: Drainage Area "P2" Subcatchment X: Drainage Area "X" Runoff Area=2.250 ac Runoff Depth=1.43" Tc=10.0 min C=0.48 Runoff=10.85 cfs 0.269 af Runoff Area=22.570 ac Runoff Depth=2.46" Tc=12.9 min C=0 .76 Runoff=171 .09 cfs 4.618 af Runoff Area=24.820 ac Runoff Depth=1 .37" Tc=16.9 min C=0 .55 Runoff=104.72 cfs 2.834 af Reach 1R: Discharge Channel Peak Depth=1 .57' Max Vel=5.0 fps lnflow=93.34 cfs 4.617 af n=0.030 L=10.0' S=0.0100 'f Capacity=157.29 cfs Outflow=93.33 cfs 4.617 af Pond 1P: Detention Pond Peak Elev=284.81' Storage=82,196 cf lnflow=171 .09 cfs 4.618 af Primary=93.34 cfs 4.617 af Secondary=0.00 cfs 0.000 af Outflow=93.34 cfs 4.617 af Total Runoff Area= 49.640 ac Runoff Volume= 7.720 af Average Runoff Depth= 1.87" CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 50-Year Duration=13 min, lnten=9.97 in/hr Prepared by {enter your company name here} Page 39 HydroCAD® 7 .10 sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Subcatchment P1 : Drainage Area "P1" Runoff = 10.85 cfs @ 0.17 hrs, Volume= 0.269 af, Depth= 1.43" Runoff by Rational method, Rise/Fall=1.0/2.0 xTc, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs TX-Brazos County 50-Year Duration=13 min, lnten=9.97 in/hr Area (ac) C 2.250 0.48 Tc Length (min) (feet) 10.0 12 11 10- 9 8- 5 4- 3 2 Description Post-Development conditions with M.D.W . Centre Slope Velocity Capacity Description (ft/ft) (ft/sec) ( cfs) Direct Entry, Proposed Conditions Subcatchment P1: Drainage Area "P1" Hydrograph TX-Brazos County 50-Year Duration=13 min, lnten=9.97 in/hr Runoff Area=2.250 ac Runoff Volume=0.269 af Runoff Depth=1.43" Tc=10.0 min C=0.48 0+-----.....-----.--......... ----__,. __ ...,.. ___________________ ,,__ ____ __, __ __,. __ _,.. __ -1 0 2 3 Time (hours) I-Runoff! CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 50-Year Duration=13 min, lnten=9.97 in/hr Prepared by {enter your company name here} Page 40 HydroCAD® 7 .10 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Subcatchment P2: Drainage Area "P2" Runoff = 171.09 cfs @ 0.22 hrs, Volume= 4.618 af, Depth= 2.46" Runoff by Rational method, Rise/Fall=1 .0/2.0 xTc, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs TX-Brazos County 50-Year Duration=13 min, lnten=9.97 in/hr Area (ac) C 22.570 0.76 Tc Length (min) (feet) 12.9 190 180 170 160~ 150 140 130 120 :f' 110 ~ 100 ~ 90 u: 80 70 60 50 40 30 20 10 Description Proposed drainage conditions to Detention Facility Slope Velocity Capacity Description (ft/ft) (ft/sec) ( cfs) Direct Entry, Proposed conditions Subcatchment P2: Drainage Area "P2" Hydrograph TX-Brazos County 50-Year Duration=13 min, lnten=9.97 in/hr Runoff Area=22.570 ac Runoff Volume=4.618 af Runoff Depth=2.46" Tc=12.9 min C=0.76 o~------------....... ---------------------------------------.-----.----------1 0 2 3 Time (hours) I-Runottj CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 50-Year Ouration=13 min, lnten=9.97 in/hr Prepared by {enter your company name here} Page 41 HydroCAD® 7 .10 sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Subcatchment X: Drainage Area "X" (48] Hint: Peak<CiA due to short duration Runoff = 104. 72 cfs @ 0.22 hrs, Volume= 2.834 af, Depth= 1.37" Runoff by Rational method, Rise/Fall=1.0/2.0 xTc, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs TX-Brazos County 50-Year Duration=13 min , lnten=9.97 in/hr Area (ac) C Description 24.820 0.55 Project Site Pre-Development Conditions Tc Length (min) (feet) 16.9 115 110 105 100 95 90 70 ~ 65 60 ~ 55 u:: 50 45 20 15 Slope Velocity Capacity Description (ft/ft) (ft/sec) (cfs) Direct Entry, Existing Conditions Subcatchment X: Drainage Area "X" Hydrograph TX-Brazos County 50-Year Duration=13 min, lnten=9.97 in/hr Runoff Area=24.820 ac Runoff Volume=2.834 af Runoff Depth=1.37" Tc=16.9 min C=0.55 2 Time (hours) I-Runottl ' 3 CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 50-Year Duration=13 min, lnten=9.97 in/hr Prepared by {enter your company name here} Page 42 HydroCAD® 7 .10 s/n 003394 ©, 2005 HydroCAD Software Solutions LLC 5/25/2006 Reach 1 R: Discharge Channel [79] Warning: Submerged Pond 1 P Primary device # 2 by 1.57' Inflow Area= 22.570 ac, Inflow Depth > 2.45" for 50-Year event Inflow = 93.34 cfs@ 0.41 hrs, Volume= 4.617 af Outflow = 93.33 cfs @ 0.42 hrs, Volume= 4.617 af, Atten= 0%, Lag= 0.1 min Routing by Ster-Ind+ Trans method, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs Max. Velocity= 5.0 fps, Min. Travel Time= 0.0 min Avg. Velocity = 2.1 fps , Avg. Travel Time= 0.1 min Peak Depth= 1.57' @ 0.41 hrs Capacity at bank full= 157 .29 cfs Inlet Invert= 279.00', Outlet Invert= 278.90' 20.00' x 2.00' deep Parabolic Channel, n= 0.030 Rubble masonry, cemented Length= 10.0' Slope= 0.0100 '/' Reach 1 R: Discharge Channel Hydrograph 100 95 93.33 cfs 90 Inflow Area=22.570 ac 85 80 Peak Depth=1.57' 75 70 Max Vel=S.O fps 65 ~ 60 n=0.030 55 ~ 50 L=10.0' 0 ii: 45 · 40 ' S=0.0100 '/' 35 30 Capacity=157.29 cfs 25~ 20 5 2 Time (hours) 3 -Inflow -Outflow CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 50-Year Duration=13 min, lnten=9.97 in/hr Prepared by {enter your company name here} Page 43 HydroCAD® 7 .1 O sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 .t: Q. .. c 20 40 60 Reach 1 R: Discharge Channel Stage-Storage 1-storagel 80 100 120 140 160 180 200 220 240 260 Storage (cubic-feet) CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 50-Year Duration=13 min, lnten=9.97 in/hr Prepared by {enter your company name here} Page 44 HydroCAD® 7 .10 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Pond 1 P: Detention Pond Inflow Area= 22.570 ac, Inflow Depth = 2.46" 171 .09 cfs @ 0.22 hrs, Volume= 93.34 cfs @ 0.41 hrs, Volume= 93.34 cfs @ 0.41 hrs, Volume= 0.00 cfs @ 0.00 hrs, Volume= for 50-Year event 4.618 af Inflow = Outflow = Primary = Secondary= 4.617 af, Atten= 45%, Lag= 11 .7 min 4.617 af 0.000 at Routing by Ster-Ind method, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs Peak Elev= 284.81' @ 0.41 hrs Surf.Area= 18,039 sf Storage= 82, 196 cf Plug-Flow detention time= 13.8 min calculated for 4.617 af (100% of inflow) Center-of-Mass det. time= 13.7 min ( 31 .0-17.2) Volume #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 #13 Invert 279.00' 279.25' 283.02' 279.35' 280.75' 283.43' 279.68' 280.42' 281.16' 282.27' 282.27' 282.27' 279.60' Avail.Storage Storage Description 89, 769 cf Custom Stage Data -Pond (Prismatic) Listed below (Recalc) 3,394 cf 42.0"D x 352.74'L Horizontal Cylinder -System "A" S= 0.0090 '/' 1,414 cf 36.0"D x 200.05'L Horizontal Cylinder-System "A" S= 0.0090 '/' 227 cf 30.0"D x 46.33'L Horizontal Cylinder-System "B" S= 0.0195 '/' 348 cf 24.0"D x 110.86'L Horizontal Cylinder-System "B" S= 0.0195 '/' 101 cf 18.0"D x 57.18'L Horizontal Cylinder-System "B" S= 0.0050 '/' 334 cf 36.0"D x 47.19'L Horizontal Cylinder-System "C" S= 0.0050 '/' 697 cf 24.0"D x 221. 72'L Horizontal Cylinder-System "C" S= 0.0030 '/' 78 cf 18.0"D x 43.91'L Horizontal Cylinder-System "C" S= 0.0100 '/' 375 cf 18.0"D x 212.46'L Horizontal Cylinder-System "C" S= 0.0050 '/' 212 cf 18.0"D x 120.00'L Horizontal Cylinder-System "C" S= 0.0100 '/' 318 cf 18.0"D x 180.00'L Horizontal Cylinder-System "C" S= 0.0100 '/' 45 cf 18.0"D x 25.50'L Horizontal Cylinder-System "D" S= 0.0100 '/' 97 ,312 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store {feet} {sg-ft} 279.00 0 279.50 10,780 280.00 11 ,261 281 .00 12,375 282.00 13,482 283.00 14,742 284.00 16,047 285.10 17,463 285.60 18,057 Device Routing Invert #1 Secondary 285.1 O' #2 Primary 279.00' {cubic-feet} {cubic-feet} 0 0 2,695 2,695 5,510 8,205 11,818 20 ,023 12,929 32,952 14,112 47,064 15,395 62 ,458 18,431 80 ,889 8,880 89,769 Outlet Devices 6.0' long x 10.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.49 2.56 2. 70 2.69 2.68 2.69 2.67 2.64 42.0" Vert. Orifice/Grate C= 0.600 CUMC -Drainage Report -Rev No . 1 CUMC H&H-Rev 1 TX-Brazos County 50-Year Duration=13 min, lnten=9.97 in/hr Prepared by {enter your company name here} Page 45 HydroCAD® 7 .1 O s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Primary OutFlow Max=93.32 cfs@ 0.41 hrs HW=284.81' (Free Discharge) L2=0rifice/Grate (Orifice Controls 93.32 cfs@ 9.7 fps) ~condary OutFlow Max=0.00 cfs@ 0.00 hrs HW=279.00' (Free Discharge) 1=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Pond 1 P: Detention Pond Hydrograph 190-.r-~~~~~~~~~~~~~~~~~~~~~~~~~~----. 180 . 171.09cfs 170 160 . 150 140 130 . 120~ i' 110- ~ 100- ~ 90 ~ ii: 80~ 70 · 60- 50 . 40 : 30- 20 0.00 cfs 0 0 Inflow Area=22.570 ac Peak Elev=284.81' Storage=82, 196 cf 2 Time (hours) 3 -Inflow -Outflow -Primary -Secondary CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 50-Year Duration=13 min, lnten=9.97 in/hr Prepared by {enter your company name here} Page 46 HydroCAD® 7 .10 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 287- 286- 285- i 284~ c 0 ~ 283 ijj 282 281 - 280 10,000 20,000 Pond 1 P: Detention Pond Stage-Area-Storage I-Storage I + + 40,000 50,000 60,000 70,000 80,000 90,000 Storage (cubic-feet) CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 100-Year Duration=13 min, lnten=10.40 in/hr Prepared by {enter your company name here} Page 47 HydroCAD® 7 .10 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Time span=0.00-3.00 hrs, dt=0.01 hrs, 301 points Runoff by Rational method, Rise/Fall=1 .0/2.0 xTc Reach routing by Ster-Ind+ Trans method -Pond routing by Ster-Ind method Subcatchment P1: Drainage Area "P1" Subcatchment P2: Drainage Area "P2" Subcatchment X: Drainage Area "X" Runoff Area=2.250 ac Runoff Depth=1 .50" Tc=10.0 min C=0.48 Runoff=11.33 cfs 0.281 af Runoff Area=22.570 ac Runoff Depth=2.56" Tc=12.9 min C=0 .76 Runoff=178.53 cfs 4.818 af Runoff Area=24.820 ac Runoff Depth=1.43" Tc=16.9 min C=0 .55 Runoff=109.28 cfs 2.957 af Reach 1 R: Discharge Channel Peak Depth= 1.59' Max Vel=5.1 fps lnflow=96.14 cfs 4.818 af n=0.030 L=10 .0' S=0.0100 'f Capacity=157.29 cfs Outflow=96.14 cfs 4.818 af Pond 1P: Detention Pond Peak Elev=285.06' Storage=86,693 cf lnflow=178.53 cfs 4.818 af Primary=96.14 cfs 4.818 af Secondary=0.00 cfs 0.000 at Outflow=96.14 cfs 4.818 af Total Runoff Area= 49.640 ac Runoff Volume= 8.056 af Average Runoff Depth= 1.95" CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 100-Year Duration=13 min, lnten=10.40 in/hr Prepared by {enter your company name here} Page 48 HydroCAD® 7 .10 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Subcatchment P1: Drainage Area "P1" Runoff = 11.33 cfs @ 0.17 hrs, Volume= 0.281 at, Depth= 1.50" Runoff by Rational method, Rise/Fa11=1 .0/2.0 xTc, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs TX-Brazos County 100-Year Duration=13 min, lnten=10.40 in/hr Area (ac) C Description 2.250 0.48 Post-Development conditions with M.D.W. Centre Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.0 Direct Entry, Proposed Conditions Subcatchment P1 : Drainage Area "P1" Hydrograph 12 11 TX-Brazos County 100-Year 10 Duration=13 min, 9 lnten=10.40 in/hr 8 Runoff Area=2.250 ac ~ 7 Runoff Volume=0.281 af ~ ~ 6 Runoff Depth=1.50" 0 u: 5 Tc=10.0 min 4 C=0.48 3 2 Time (hours) I-Runoff~ ' 3 CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 100-Year Duration=13 min, lnten=10.40 in/hr Prepared by {enter your company name here} Page 49 HydroCAO® 7 .10 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Subcatchment P2: Drainage Area "P2" Runoff = 178.53 cfs @ 0.22 hrs, Volume= 4.818 af, Depth= 2.56" Runoff by Rational method, Rise/Fall=1 .0/2.0 xTc, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs TX-Brazos County 100-Year Duration=13 min , lnten=10.40 in/hr Area (ac) C Description 22.570 0.76 Proposed drainage conditions to Detention Facility Tc Length (min) (feet) 12.9 190 180 110· 160 150 140 . 130 120 . ~ 110: ; 100 £ 90 80 Slope Velocity Capacity Description (ft/ft) (ft/sec) ( cfs) Direct Entry, Proposed conditions Subcatchment P2: Drainage Area "P2" Hydrograph TX-Brazos County 100-Year Duration=13 min, lnten=10.40 in/hr Runoff Area=22.570 ac Runoff Volume=4.818 af Runoff Depth=2.56" Tc=12.9 min C=0.76 o-+,---.-------..,.------r----.--...... -------.---~.--...... ------------~ 0 2 3 Time (hours) I-Runoff I CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 100-Year Duration=13 min, lnten=10.40 in/hr Prepared by {enter your company name here} Page 50 HydroCAD® 7 .10 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Subcatchment X: Drainage Area "X" [48] Hint: Peak<CiA due to short duration Runoff = 109.28 cfs @ 0.22 hrs, Volume= 2.957 af, Depth= 1.43" Runoff by Rational method, Rise/Fall=1.0/2.0 xTc, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs TX-Brazos County 100-Year Duration=13 min, lnten=10.40 in/hr Area (ac) C 24.820 0.55 Tc Length (min) (feet) 16.9 120~ 115 110 105 . 100 95 90 85 80 75 -70 ~ 65 :r: 60 0 55 u: 50 45 40 35 30 25 20 15- 10 5 0 0 Description Project Site Pre-Development Conditions Slope Velocity Capacity Description (ft/ft) (ft/sec) ( cfs) Direct Entry, Existing Conditions Subcatchment X: Drainage Area "X" Hydrograph TX-Brazos County 100-Year Duration=13 min, lnten=10.40 in/hr Runoff Area=24.820 ac Runoff Volume=2.957 af Runoff Depth=1.43" Tc=16.9 min C=0.55 2 Time (hours) I -Runoff~ 3 CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 100-Year Duration=13 min, lnten=10.40 in/hr Prepared by {enter your company name here} Page 51 HydroCAD® 7.10 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Reach 1 R: Discharge Channel [79] Warning: Submerged Pond 1 P Primary device # 2 by 1.59' Inflow Area= 22.570 ac, Inflow Depth > 2.56" for 100-Year event Inflow = 96.14 cfs@ 0.42 hrs, Volume= 4.818 at Outflow = 96.14 cfs @ 0.42 hrs, Volume= 4.818 at, Atten= 0%, Lag= 0.1 min Routing by Star-Ind+ Trans method, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs Max. Velocity= 5.1 fps, Min. Travel Time= 0.0 min Avg. Velocity= 2.1 fps, Avg . Travel Time= 0.1 min Peak Depth= 1.59' @ 0.42 hrs Capacity at bank full= 157 .29 cfs Inlet Invert= 279.00', Outlet Invert= 278.90' 20.00' x 2.00' deep Parabolic Channel, n= 0.030 Rubble masonry, cemented Length= 10.0' Slope= 0.0100 '/' ~ ~ ~ u:: 105 ~ 100~ 95~ 90 85~ 65 60 55 50 45 40 35 30 25 20 15 10 5 Reach 1 R: Discharge Channel Hydrograph Inflow Area=22.570 ac Peak Depth=1.59' Max Vel=S.1 fps n=0.030 L=10.0' S=0.0100 '/' Capacity=157 .29 cfs 2 Time (hours) 3 . -Inflow -Outflow CUMC -Drainage Report -Rev No. 1 CUMC H&H~Rev 1 TX-Brazos County 100-Year Duration=13 min, lnten=10.40 in/hr Prepared by {enter your company name here} Page 52 HydroCAD® 7 .1 O s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 ' 20 40 60 80 Reach 1 R: Discharge Channel Stage-Storage 100 120 140 160 180 200 220 240 Storage (cubic-feet) 1-storagej 260 CUMC -Drainage Report -Rev No . 1 CUMC H&H-Rev 1 TX-Brazos County 100-Year Duration=13 min, lnten=10.40 in/hr Prepared by {enter your company name here} Page 53 HydroCAD® 7.10 sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Pond 1 P: Detention Pond Inflow Area= 22 .570 ac, Inflow Depth = 2.56" for 100-Year event 4.818 af Inflow = Outflow = Primary = Secondary= 178.53 cfs @ 0.22 hrs, Volume= 96.14 cfs@ 0.42 hrs, Volume= 96.14 cfs@ 0.42 hrs, Volume= 0.00 cfs @ 0.00 hrs, Volume= 4.818 af, Atten= 46%, Lag= 11.9 min 4.818 af 0.000 at Routing by Star-Ind method, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs Peak Elev= 285.06' @ 0.42 hrs Surf.Area= 18,227 sf Storage= 86 ,693 cf Plug-Flow detention time= 13.9 min calculated for 4.818 af (100% of inflow) Center-of-Mass det. time= 13.9 min ( 31.1 -17.2) Volume #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 #13 Elevation (feet) 279.00 279.50 280.00 281 .00 282.00 283.00 284.00 285.10 285.60 Invert Avail.Storage Storage Description 279.00' 279.25' 283.02' 279.35' 280.75' 283.43' 279.68' 280.42' 281.16' 282.27' 282.27' 282.27' 279.60' Surf.Area (sq-ft) 0 10,780 11,261 12,375 13,482 14,742 16,047 17,463 18,057 89,769 cf Custom Stage Data -Pond (Prismatic) Listed below (Recalc) 3,394 cf 42.0"D x 352.74'L Horizontal Cylinder -System "A" S= 0.0090 '/' 1,414 cf 36.0"D x 200.05'L Horizontal Cylinder-System "A" S= 0.0090 '/' 227 cf 30.0"D x 46.33'L Horizontal Cylinder-System "B" S= 0.0195 '/' 348 cf 24.0"D x 110.86'L Horizontal Cylinder-System "B" S= 0.0195 '/' 101 cf 18.0"D x 57.18'L Horizontal Cylinder-System "B" S= 0.0050 '/' 334 cf 36.0"D x 47.19'L Horizontal Cylinder-System "C" S= 0.0050 '/' 697 cf 24.0"D x 221.72'L Horizontal Cylinder-System "C" S= 0.0030 '/' 78 cf 18.0"D x 43.91'L Horizontal Cylinder-System "C" S= 0.0100 '/' 375 cf 18.0"D x 212.46'L Horizontal Cylinder-System "C" S= 0.0050 '/' 212 cf 18.0"D x 120.00'L Horizontal Cylinder-System "C" S= 0.0100 '/' 318 cf 18.0"D x 180.00'L Horizontal Cylinder-System "C" S= 0.0100 '/' 45 cf 18.0"D x 25.50'L Horizontal Cylinder-System "D" S= 0.0100 '/' 97 ,312 cf Total Available Storage Inc.Store (cubic-feet) 0 2,695 5,510 11 ,818 12,929 14,112 15,395 18,431 8,880 Cum .Store (cubic-feet) 0 2,695 8,205 20,023 32 ,952 47,064 62 ,458 80,889 89 ,769 Device Routing Invert Outlet Devices #1 Secondary 285.1 O' 6.0' long x 10.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64 #2 Primary 279.00' 42.0" Vert. Orifice/Grate C= 0.600 CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 100-Year Duration=13 min, lnten=10.40 in/hr Prepared by {enter your company name here} Page 54 HydroCAD® 7 .10 sin 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Primary OutFlow Max=96.13 cfs@ 0.42 hrs HW=285.06' (Free Discharge) "t__2=0rifice/Grate (Orifice Controls 96.13 cfs@ 10.0 fps) t:_condary OutFlow Max=0.00 cfs@ 0.00 hrs HW=279.00' (Free Discharge) 1=Broad-Crested Rectangular Weir (Controls 0.00 cfs) 190 180 170 160 150 140 130- 120 i' 110-u ; 100 ~ 90 80 70 . 60 50 40 . 30 20-; 0.00 cfs 0 0 Pond 1 P: Detention Pond Hydrograph Inflow Area=22.570 ac Peak Elev=285.06' Storage=86,693 cf 2 Time (hours) -Inflow -Outflow -Primary -Secondary 3 CUMC -Drainage Report -Rev No. 1 CUMC H&H-Rev 1 TX-Brazos County 100-Year Duration=13 min, lnten=10.40 in/hr Prepared by {enter your company name here} Page 55 HydroCAD® 7 .10 s/n 003394 © 2005 HydroCAD Software Solutions LLC 5/25/2006 Pond 1 P: Detention Pond Stage-Area-Storage 287 I-Storage I 286 285- ! 284 c: 0 :; 283 > .. iii 282 281 280- 279 . ' 0 10,000 20,000 30,000 40,000 50,000 60,000 70,000 80,000 90,000 Storage (cubic-feet)