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HomeMy WebLinkAboutDrainage Report- DRAINAGE REPORT FOR THE PROPOSED AMERISUITES HOTEL DEVELOPMENT COLLEGE STATION, TEXAS Prepared for Kyle Legends I, LP 7502 Greenville Avenue Dallas, Texas 75231 Submitted to City of College Station Development Services 1101 Texas Avenue College Station, Texas 77842 Prepared by CSC Engineering & Environmental Consultants, Inc. 3407 Tabor Road Bryan, Texas 77808 June 2004 'In.~~ M. Frederick Conlin, P.E. W.R. Cullen, P.E. QA/QC Reviewer Senior Engineer CSC ENGINEERING & ENVIRONMENTAL CONSULTANTS, INC. Report of Drai nage Study fo r AmeriSuites Hotel Development TABLE OF CONTENTS Page 1.0 GENERAL DESCRIPTION OF SITE AND PROPOSED DEVELOPMENT ............................. . 2.0 PRE-DEVELOPMENT DRAJNAGE PATTERNS AND MAJOR DRAJNAGE BASINS........... 2 3.0 SCOPE OF REPORT AND DRAINAGE DESIGN CRITERIA.................................................... 2 4.0 STORM WATER RUNOFF COMPUTATIONS........................................................................... 2 4.1 USE OF THE RATIONAL FORMULA............................................................................... 2 4.2 RUNOFF COEFFICIENTS (C) ............................................................................................ 3 4.3 TIME OF CONCENTRATION (Tc)..................................................................................... 5 4.4 RAINFALL INTENSITY (I)................................................................................................. 5 4.5 AREA OF SITE (A).............................................................................................................. 6 4.6 STORM WATER RUNOFF QUANTITIES......................................................................... 6 5.0 STORM WATER DETENTION COMPUTATIONS.................................................................... 7 5.1 REQUIRED MINIMUM DETENTION STORAGE VOLUME.......................................... 7 5.2 DETENTION BASIN STORAGE AREA............................................................................ 7 5.3 DETENTION BASIN OUTLET STRUCTURE................................................................... 8 6.0 STORM WATER ROUTING COMPUTATIONS......................................................................... 9 6.1 METHODOLOGY ................................................................................................................ 9 6.2 ROUTING COMPUTATIONS AND CONCLUSIONS...................................................... 9 7 .0 EROSION CONTROL MEASURES ............................................................................................. 10 7.1 GENERAL CONSIDERATIONS ......................................................................................... 10 8.0 CERTIFICATION ........................................................................................................................... 10 9.0 REFERENCES ................................................................................................................................ 11 LIST OF TABLES Table 1. Summary of Determination of Runoff Coefficient (C) Values for Post-Development Conditions for Entire Site ............................................................................................... ,...... 4 Table 2. Computed Rainfall Intensity Values for Defined Storm Return Period ................................ 6 Table 3. Calculation of Pre-and Post-Development Storm Water Runoff Quantities Using the Rational Method . . . .. . . . .. . . . . . . . . . .. . . . . . . . .. .. .. . .. . . . . .. . . . . . . . . .. .. .. .. . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . .. . . . . 6 II CSC ENGINEERING & ENVIRONMENTAL CONSULTANTS, INC. Report of Drainage Study for AmeriSuites Hotel Development Figure I. Figure 2. Figure 3. Figure 4. Figure 5. Figure 6. Figure 7. Figure 8. Figure 9. Figure 10. Figure 11. LIST OF FIGURES Vicinity Map AmeriSuites Hotel Carter Creek Drainage Basin General Site Map and Currently Planned Development Scheme Pre-Development Site Surface Storm Water Runoff Flow Patterns Post-Development Site Grading Plan and Surface Storm Water Runoff Flow Patterns Post-Development Site Drainage Basin and Sub-basin Boundaries Types of Site Cover Materials AmeriSuites Hotel Pre-and Post-Development Hydrographs -100-Y ear Event AmeriSuites Hotel (for Determining Minimum Required Volume of Detention Basin) Storm Water Detention Basin Storage Depth versus Storage Volume Cumulative Outflow (Discharge) versus Depth of Storage Inflow and Outflow Hydrographs Illustrating Routing for 100-Y ear Storm Event 111 CSC ENGINEERING & ENVIRONMENTAL CONSULTANTS, INC. Report of Drainage Study for AmeriSuites Hotel Development 1.0 GENERAL DESCRIPTION OF SITE AND PROPOSED DEVELOPMENT Information concerning the project was provided by Mr. Tom Kirkland of Kyle Legends I, LP and available site development information developed by CSC in conjunction with Arkitex Studio, Inc. The site of the proposed hotel is a 2.40-acre tract that is situated on the south side of University Drive (Figure I), approximately 600 ft west of the intersection with Lincoln A venue in College Station, Texas. The site is roughly square in shape with approximate average dimensions of 280 ft by 385 ft and can be described as undeveloped improved pastureland. The site borders University Drive to the north, the existing McAlister's Deli and Quality Suites properties to the west, and undeveloped properties of the Wheeler Estate to the south and east. This development site is located in the Carter Creek drainage basin where a tributary of Burton Creek flows from south-southwest to north-northeast near the southern boundary of the subject site. The subject site is situated such that the northern portion of the tract, near University Drive, is mostly natural grasslands with some isolated trees and native shrubs. The southern portion of the tract, near the tributary creek, contains some native Post and Water Oaks mixed with smaller mid-story vegetation. The existing topography of the site is relatively steep from the higher elevations in the northwestern corner of the site to the lower elevations along the existing tributary to Burton Creek that forms the southern boundary of the site (Figure 4). Existing ground surface elevations range from approximately El. 306 near the northwestern corner of the property to approximately El. 283 near the previously referenced tributary. The average surface grade in the cleared area of the site is approximately 4.0 percent, with steeper grades being present near the creek tributary. The site does not appear to have been the subject of past development and can be considered as improved rangeland. We understand that the proposed hotel building will be a four (4) story structure that will have a total gross floor area (all four (4) floors combined) of approximately 68,000 square feet (sq ft). The hotel will have approximately 91 rooms or units. The hotel structure will also have ground floor meeting rooms with a total meeting area of approximately 1,000 to 1,200 sq ft, as well as indoor swimming pool, exercise room, etc. The building is expected to be rectangular in shape with approximate plan dimensions of 70 ft by 235 ft and a total footprint or ground floor plan area of approximately 16,000 sq ft. We anticipate that the proposed development wi ll include paved parking and drive areas surrounding the hotel. Approximately 100 parking spaces are currently planned for the development. Landscaping of the site will be conducted in the areas around the building, in between the proposed parking and University Drive, and the islands and areas bordering the parking facilities. CSC ENGINEERING & ENVIRONMENTAL CONSULTANTS, INC. Report of Drainage Study for AmeriSuites Hotel Development 2.0 PRE-DEVELOPMENT DRAINAGE PATTERNS AND MAJOR DRAINAGE BASINS As previously discussed, the subject 2.40-acre site is located in the Burton Creek sub-basin of the Carter Creek drainage basin. As illustrated on Figure 2, the subject site is situated near the upper portion of the tributary to Burton Creek. The distinct drainage channel or tributary crosses the existing site along the southern property boundary. The major portion of current storm water runoff from the site appears to be by sheet-flow in a southerly or southeasterly direction toward the previously described existing tributary of Burton Creek (Figure 4). According to a recent floodplain study provided to CSC by the City of College Station, a portion of the 2.40-acre site appears to lie within the I 00-year floodplain and flood way. 3.0 SCOPE OF REPORT AND DRAINAGE DESIGN CRITERIA This report addresses the required detention of storm water runoff from the subject site as a result of the planned hotel development. The site and proposed development were evaluated in accordance with the criteria outlined in the ''Drainage Policy and Design Standards (DPDS)" manual of the City of College Station, Texas. The DPDS manual is undated but contains a chapter on "Flood Hazard Protection" that has a revision date of October 1, 1990. This report also discusses specific drainage control structures related to the detention of storm water runoff from the new facility and general erosion control measures. 4.0 STORM WATER RUNOFF COMPUTATIONS 4.1 USE OF THE RATIONAL FORMULA The Rational Formula was used to compute the volume of storm water runoff prior to and following the planned development. Calculations based upon the Rational Formula were employed to assess the quantity of storm water that must be detained to "offset" the increased runoff associated with the new development. The general grading plan for the proposed development, the patterns of post- development storm water runoff flows, and the location and approximate area of the proposed detention basin are illustrated on the accompanying Figure 5. 2 CSC ENGINEERING & ENVIRONMENTAL CONSULTANTS, INC. Report of Drainage Study for AmeriSuites Hotel Development Use of the Rational Formula is reasonable for this project since the contributory area of runoff is less than 50 acres, an area sometimes referenced in the literature as an upper limit for use of the Rational Formula. In addition, the subject site is located within a Secondary Drainage System and not within a Primary Drainage System. The Rational Formula is not recommended for use within a Primary Drainage System. Therefore, the Rational Formula was used to determine the peak discharge for both pre-and post- development conditions. The general equation for the Rational Formula is well known: Q =CIA where Q =discharge of storm water in units of cubic feet per second (cfs) C = coefficient that represents the average runoff characteristics of the land cover within the drainage area of interest, i.e., the runoff coefficient, which is dimensionless I = rainfall intensity in units of inches per hour (in/hr), and A = area of the site that contributes to the storm water runoff in units of acres The numbers for each of the values used to compute the storm water runoff at the subject site are discussed in the following sections. 4.2 RUNOFF COEFFICIENTS (C) The runoff coefficients or "C" values were computed for both pre-and post-development conditions. Coefficients for the different types of surface covers were determined in accordance with information presented in Table ill-1 of the DPDS manual. The coefficient for the pre-development condition was determined based upon the land cover category listed in Table ill-1 as a combination of ''Natural Woodlands" and ''Natural Grasslands" for slopes in the range of3.5% to 5.5%. A range of C-values of 0.25 to 0.30 was listed in the referenced table for the ''Natural Woodlands" and a range of C-values of 0.45 to 0.55 was given for ''Natural Grasslands" for the cited topographic conditions. Given that the majority of the site can be classified as natural grassland, an average value of 0.50 was selected for use for pre-development cover of the entire 2.40-acre site. 3 CSC ENGINEERING & ENVIRONMENTAL CONSULTANTS, INC. Report of Drainage Study for AmeriSuites Hotel Development The post-development site grading plan and surface storm water runoff flow patterns are illustrated in Figure 5. As can be seen from Figure 5, the area incorporated in our analyses for post- development included the footprint of the proposed hotel building, the proposed parking and driveway pavements, and the proposed landscaped areas. As indicated by the specific site drainage basin and sub- basin boundaries associated with development (Figure 6), not all of the developed site will be draining directly to the planned detention basin. However, the final grading plan has been developed in a manner that will allow offsite storm water runoff from the Quality Suites to be routed to the detention facility located near the southwest comer of the AmeriSuites Hotel site. The referenced drainage area consists of approximately 0.9 acres of concrete pavement that slopes from west to east toward the subject site. Storm water runoff exists at the Quality Suites site through a series of curb cuts along the western property boundary. The post-development C-values were determined from the referenced table for the specific types of site cover associated with post-developed site conditions (Figure 7). The specific types of post- development cover materials illustrated in Figure 7 and the corresponding C-values from Table III-1 of the DPDS manual were used in the analysis listed in Table 1 to compute an average C-value for the post- developed site. In general, a C-value of 0.9 was used for the building roof and concrete-covered pavements and sidewalks, and a C-value of 0.45 was used for the landscaped or grassed areas. Table 1. Summary of Determination of Runoff Coefficient (C) Values for Post-Development Conditions for Entire Site Type of Ground Cover Pavement (sidewalks, streets, etc.) Building roof Grassed or landscaped areas Summation Area of Coverage, Square Feet 47,242 17,000 40,302 104,544 Typical C-Values 0.90 0.90 0.45 Extended Multiplication of C-Values X Area 42,518 15,300 18,136 75,954 Therefore, the average C-value across the site can be determined by dividing the summation of the product of the individual areas times the respective C-values and dividing that summation by the overall area: Average C-value = 75,954 square feet/104,544 square feet = 0.726 (Use 0.73) 4 CSC ENGINEERING & ENVIRONMENTAL CONSULTANTS, INC. Report of Drainage Study for AmeriSuites Hotel Development 4.3 TIME OF CONCENTRATION (Tc) The time of concentration at a site is used to determine the intensity of the rainfall event used for computing· storm water flows and required detention volumes. The time of concentration is defined as "the time required for the runoff to be established and flow from the most remote part of the drainage area to the point under design." For pre-development conditions the time of concentration for the subject site was calculated based upon the elevation difference and the flow distance from the higher elevations· in the northwestern portion of the property to the lower elevations where the storm water leaves the property. The referenced change in elevation is 23 ft and the referenced distance is approximately 460 ft that produces a slope of approximately 5% for pre-development conditions. The slope for post-development conditions was determined from the proposed site grading plan and drainage patterns as illustrated in Figure 5. The surface slopes or grades and the velocities presented in Table ill-2 of the DPDS manual were utilized to determine the appropriate storm water runoff velocity. For overland or sheet-flow over land with slopes in the range of 4 to 7 percent, such as at the subject site, velocities of runoff flow are listed to be in the range of 1.5 to 2.5 feet per second (fps) for natural woodlands and in the range of 2.5 to 3.5 fps for natural grasslands. Accordingly, an average velocity of 2.5 fps was conservatively selected for pre-development conditions. Thus, time of travel between the location of the higher elevations of the site and exit point from the site was calculated to be approximately 184 seconds (460 ft distance/2.5 fps velocity) or approximately 3.1 minutes for pre- development conditions. Similarly, the post-development time of concentration was calculated over the paved areas of the site without consideration of any detention and was determined to be a shorter time period. Therefore, a minimum time of concentration of 10 minutes (as specified in the DPDS manual) was used in the calculations for both pre-and post-development conditions. 4.4 RAINFALL INTENSITY (I) The rainfall intensity values were computed for the minimum 10-minute time of concentration previously discussed using the intensity-duration-frequency curves developed by the Texas Department of Transportation. The computed intensities calculated for storm events with "return periods" of 5, 10, 25, 50, and 100 years are indicated in Table 2. 5 CSC ENGINEERING & ENVIRONMENTAL CONSULTANTS, INC. Report of Drainage Study for AmeriSuites Hotel Development Table 2. Computed Rainfall Intensity Values for Defined Storm Return Period Storm Return Period (Years) 4.5 AREA OF SITE (A) 5 10 25 50 100 Rainfall Intensity (Inches/Hour) 7.7 8.6 9.9 11.1 12.3 The area of the site used in the computation of storm water runoff is the original site area of 2.40 acres. 4.6 STORM WATER RUNOFF QUANTITIES Storm water runoff quantities were calculated using the Rational Formula. Runoff quantities were calculated for both pre-and post-development conditions for the 2.40-acre site and are presented in Table 3. Table 3. Calculation of Pre-and Post-Development Storm Water Runoff Quantities Using the Rational Method PRE- DEVELOPMENT Storm Event Area_ Intensityc Cpre8 Qpre (year) (acres) (inches/hr) (dless") (cfs) 5 2.40 7.7 0.50 9.2 10 2.40 8.6 0.50 10.4 25 2.40 9.9 0.50 11.8 50 2.40 11.1 0.50 13.4 100 2.40 12.3 0.50 14.8 •Average values ofC were obtained from Table Ill-I of the DPDS Manual b dless = dimensionless c Values obtained from Table 2 of this report 6 POST- DEVELOPMENT DIFFERENCE Cpost Qpost Qmff (dless"} (cfs) (cfs) 0.73 13.5 4.2 0.73 15.1 4.8 0.73 17.3 5.4 0.73 19.4 6.2 0.73 21.5 6.8 CSC ENGINEERING & ENVIRONMENTAL CONSULTANTS, INC. Report of Drainage Study for AmeriSuites Hotel Development 5.0 STORM WATER DETENTION COMPUTATIONS 5.1 REQUIRED MINIMUM DETENTION STORAGE VOLUME The storage volume of the detention area was calculated such that the peak discharge of the ultimate development hydrograpbs for the 100-year design stol'm was limited to a discharge less than a defined target discharge. The defined target discharge was characterized by the DPDS manual to be the peak discharge of the pre-development hydrograph for the 100-year storm event. Since the entire 2.40- acre site is being developed at the present time, the current developed condition and the ultimate developed condition were assumed to be the same. The required detention storage volume was determined as the difference in area between the pre- and post-development hydrographs, as depicted on Figure 8. The Triangular Approximation method was used to determine the hydrographs. The hydrographs were constructed by assuming that t~e peak discharge, as calculated from the Rational Formula, occurs at a time equal to the time of concentration and that one-third of the flow volume occurs before the peak discharge is reached and two-thirds occur following the peak discharge. The Triangular Approximation method of developing hydrographs is generally considered to be acceptable for analysis of Secondary Drainage Systems with an area of less than 50 acres, which is applicable to the drainage basin addressed in this report. The difference in area between the two hydrographs, or the required minimum volume of the detention storage area, was calculated to be approximately 6, 110 ft3 for the I 00-year event. 5.2 DETENTION BASIN STORAGE AREA We propose to construct the required detention basin on the southern comer of the project site and adjacent to the existing Burton Creek tributary as depicted in Figure 5. The proposed detention basin will be an earthen structure that is created by a combination of excavation below the existing surface grades and construction of above-grade earthen berms to provide the required volume for storm water detention. The proposed detention basin will be roughly triangular in shape to conform to the space between the back of the proposed pavement and the existing tributary. The detention basin will have an approximate length of 75 ft and a base width of approximately 35 ft as indicated in Figure 5. The total depth of the basin will be approximately 5 ft from the base of the structure 7 CSC ENGINEERING & ENVIRONMENTAL CONSULTANTS, INC. Report of Drainage Study for ArneriSuites Hotel Development to the bottom of the emergency overflow structure that will be built into the perimeter levee or embankment. The embankments for the detention basin will be formed with compacted native clay soils, excavated as part of the proposed building development or brought in from an acceptable borrow source. The embankments will have side slopes with inclinations of 3: 1 (horizontal to vertical dimension) with a minimum crest or top width of 1 ft to provide resistance to erosion or damage from mowing equipment. The slopes of the embankment will be sodded with grass following construction to minimize erosion of the embankment soils. The approximate volume provided by the proposed detention basin is illustrated on Figure 9. As can be seen from Figure 9, the full basin depth below the emergency overflow spillway elevation would provide a potential storage volume of approximately 7,400 cu ft. As previously stated, the required minimum storage volume of the detention basin would be approximately 6, 110 cu ft in order to detain the difference between the 100-year event storm water runoff for pre-and post-development conditions. The minimum required volume of 6, 111 cu ft is within the available storage capacity of the proposed basin. 5.3 DETENTION BASIN OUTLET STRUCTURE The outlet structure for the detention basin has been designed to accommodate and route collected storm water runoff from the 100-year event. A 12-in-diameter, high-density polyethylene (HOPE) pipe will be installed through the embankment to drain the detention for "normal" discharges corresponding to a 100-year event. An 4.0-ft-wide riprap section will be cut into the top of the detention basin embankment to provide "emergency overflow" discharges for storm events in excess of the 100-year event. The discharges will be routed to the previously referenced tributary of Burton Creek tributary. The diameter and slope of the HDPE outlet pipe was established to provide discharges from the detention basin during the 100-year storm event that were less than or equal to the 14.8 cfs runoff flows that were associated with the pre-development site conditions. As indicated by the graphical presentation of detention basin discharge versus depth illustrated on Figure 10, the planned pipe size and pipe grade provides for a discharge of approximately 8.2 cfs, from the detention basin with 4.6 ft depth of storm water detention, which is a flow that is less than the 14.8 cfs pre-development flow for the predevelopment 100-year storm event. The detention basin outlet pipe will discharge through the earthen side slope of the tributary stream and not at the base of the stream where the pipe outlet might become inundated for common rainfall events. Erosion of the earthen side slopes of the "receiving" tributary creek from detention basin discharges will be minimized by providing rock-rip along the slope at the discharge point. 8 CSC ENGINEERING & ENVIRONMENTAL CONSULTANTS, INC. Report of Drainage Study for AmeriSuites Hotel Development The emergency overflow will function similar to a weir to pass the outflow from storms that are in excess of the 100-year event. 6.0 STORM WATER ROUTING COMPUTATIONS 6.1 METHODOLOGY The proposed detention basin in the southwestern portion of the project site was analyzed for flow routing through the areas under the 100-year storm event. The purpose of the routing analysis was to simulate the performance of the detention basins in the form of inflow and outflow hydrograph s. The storage-routing analysis was performed based upon the Puls Method. The Puls Method is a procedure for graphicaJly solving the continuity equation for storage reservoirs using the characteristic height-storage and height-discharge curves. As previously discussed, the depth-volume storage curve for the detention basin was developed graphically from the final grading plan and is graphically depicted on Figure 9. A height-discharge or discharge versus depth of storage curve was also developed and is illustrated in Figure 10. The routing time interval was selected to be slightly less than 10 percent of the time to peak of the inflow hydrograph to ensure that the numerical averaging procedures of the Puls Method do not diminish the impact of the peak flow . 6.2 ROUTING COMPUTATIONS AND CONCLUSIONS Routing analysis was performed for the 100-year design event as required in in the DPDS. The results of the routing analyses are presented graphically on Figure 11 in the form of inflow and outflow hydrographs, the difference between the two hydrograph curves being the volume that will be stored. A review of Figure 11 for the 100-year event indicates that the basin has the capacity to store the difference between the inflow and outflow quantities without overtopping. The maximum calculated height of the stored water in the detention basin during the 100-year storm event is approximately 4.6 ft. Therefore, the detention basin has the capacity to store the excess volume of storm water associated with the planned development of the site and [to] discharge the stored water at a rate that is "equal to or less than the peak discharges of the pre-development hydrographs for the design [100-year] storm" as called for in the DPDS. 9 CSC ENGINEERING & ENVIRONMENTAL CONSULTANTS, INC. Report of Drainage Study for AmeriSuites Hotel Development Flows associated with storms that are in excess of the 100-year event will be routed via the previously discussed riprapped spillway over the embankment to the tributary to Burton Creek. The detention basin should not be damaged at the point of overtopping due to the erosion protection over the earthen berm and slope. 7.0 EROSION CONTROL MEASURES 7.1 GENERAL CONSIDERATIONS The erosion control measures proposed at the site will consist of a combination of silt fences, hay bale barriers, and sedimentation traps. The locations of the proposed erosion control measures are depicted on Sheet C 10 of the construction plans. 8.0 CERTIFICATION "I hereby certify that this report for drainage design of the storm water detention basin at the 2.40-acre site of the proposed AmeriSuites Hotel development located on the south side of the University Drive west of the Lincoln Road intersection in College Station, Texas, was prepared under my supervision in accordance with the previsions of the City of College Station "Drainage Policy and Design Standards ( 1990)" for the owners thereof." ~:ro~~· Registered Professional Engineer State of Texas P .E. Number 44481 IO CSC ENGINEERING & ENVIRONMENTAL CONSULTANTS, INC. Report of Drainage Study for AmeriSuites Hotel Development 9.0 REFERENCES Chow, Ven T., Maidment, David R., and Mays, Larry W. 1988. Applied Hydrology. McGraw-Hill Book Company. New York, NY. 1988. City of College Station, Texas. 1990. "Drainage Policy and Design Standards," part of the Storm Water Management Plan for the City of College Station. October, 1, 1990. Davis, Victor D., and Sorensen, Kenneth E. 1969. Handbook of Applied Hydraulics. McGraw-Hill Book Company. New York, NY. 1969. Hann, C. T., Barfield, B. J., and Hayes, C. J. 1994. Design Hydrology and Sedimentology for Small Catchments. Academic Press, Inc. San Diego, CA. 1994. Mason, John M. and Rhombrerg, Edward L. 1980. On-Site Detention. Prepared for Texas Engineering Extension Service, Texas A& M University. College Station, TX. 1980. Publication No. PWP: 03355-01. McCuen, Richard H. A Guide to Hydrologic Analysis Using SCS Methods. Prentice-Hall, Inc. Englewood Cliffs, NJ. 1982. United States Department of Agriculture. 1975. Urban Hydrology for Small Watersheds. Technical Release No. 55 . Engineering Division, Soils Conservation Service, U.S. Department of Agriculture. January 1975. Wanielista, Martin P. 1978. Stormwater Management Quantity and Quality. Ann Arbor Science. Ann Arbor, MI. 1978. Westaway, C.R. and Loomis, A. W. 1979. Cameron Hydraulic Data. (16th Edition). Ingersoll-Rand. Woodcliff Lake, NJ. 1979. 11 FIGURES I c s c Eurl Rudder Gol f Course £11si11c,·ri1tR & £111'irm1111,·111al C.mwlram.<. lne. Prepared For: KYLE LEGENDS I, LP VICINITY MAP AMERISUITES HOTEL PROJECT: AMERISUITES HOTEL LOCATION: COLLEGE STATION, TEXAS APPR: MFC REV. DATE: '-····-.... DRAWN BY: JBF SCALE: AS SHOWN DATE: 06/07/04 FIGURE NO.: 1 ' ' NIVEASITY / ' \ I I " \ \ ' / \ I c s c Prepared For: KYLE LEGENDS I, LP r-- ' ------.J ------ CARTER CREEK DRAINAGE AREA AMERISUITES HOTEL PROJECT: AMERISUITES HOTEL LOCATION: COLLEGE STATION , TEXAS APPR: MFG REV. DATE: DRAWN BY: TM SCALE: AS SHOWN DATE: 06/07/04 FIGURE NO.: 2 .·.·.;.; ..... •.! \ c s c \ ' ' \ fn,:mreritt;: & E11wr,mmt11tal %t-'4:n:;, (.,{m.m/1.mu~. ltw. UNIVERSITY DRIVE ' ' \ GENERAL SITE MAP AND CURRENTLY PLANNED DEVELOPMENT SCHEME ..---..----_..---- reps or: KYLE LEGENDS I, LP __ ..---- -No~~ j I INFORMATION PRESENTED IN THIS DRAWING IS FOR INFORMATIONAL PURPOSES ONLY AND NOT INTENDED TO BE USED IN CONSTRUCTION. PROJECT: AMERISUITES HOTEL LOCATION: COLLEGE STATION TEXAS APPR: MFC REV. DATE: DRAWN BY; JBF SCALE: AS SHOWN DATE: 06/07/04 FIGURE NO.: 3 \ ,.-"'" .... 1 DENOTES GENERAL DIRECTION OF SURFACE STORMWATER RUNOFF c s c Enxilfcerii:.'1' A: £m1rtJ11menttd l'fm~11/u11m. /Ji(". UNIVERSITY DRIVE PRE-DEVELOPMENT SITE SURFACE STORM WATER RUNOFF FLOW PATTERNS re pare or: KYLE LEGENDS I, LP PROJECT: AMERSUITES HOTEL LOCATION: COLLEGE STATION TEXAS APPR: MFC REV. DATE: 60 I DRAWN BY: JBF SCALE: AS SHOWN DATE: 06/07/04 FIGURE NO.: 4 FEET ( / /' ---·---f\"" ·, \/ , ...... , \ \ NOTE INFORMATION PRESENTED IN THIS DRAWING IS FOR INFORMATIONAL PURPOSES ONLY AND NOT INTENDED TO BE USED IN CONSTRUCTION. I c s c £tt-xmcering & lrm1rtPtm1:mn.I C•'l1tsJ1flullts, hw PROPOSED DETENTION BASIN AND OUTLET STRUCTURE POST-DEVELOPMENT SITE GRADING PLAN AND SURFACE STORM WATER RUNOFF FLOW PATTERNS UNIVERSITY DRIVE re pa or: KYLE LEGEND I, LP ---DENOTES GENERAL DIRECTION OF SURFACE STORMWATER RUNOFF PROJECT: AMERISUITES HOTEL LOCATION: COLLEGE STATION TEXAS APPR: MFC REV. DATE: DRAWN BY: JBF SCALE: AS SHOWN DATE: 06/07/04 FIGURE NO.: 5 ~ - c KEY AREA DRAINING DIRECTLY TO CREEK -0.62 ac. AREA DRAINING TO DETENTION BASIN -1 .78 ac. DENOTES GENERAL DIRECTION OF SURFACE STORMWATER RUNOFF UNIVERSITY DRIVE DETENTION BASIN reps re or: I s c £nxim·e111t.t: & Em1rumtzcmf11 Consul!ttm'i. bu· POST-DEVELOPMENT SITE DRAINAGE BASIN AND SUB-BASIN BOUNDARIES KYLE LEGENDS I, LP PROJECT: AMERISUITES HOT L LOCATION: COLLEGE STATION TEXAS APPR: MFC REV. DATE: DRAWN BY: JBF SCALE: AS SHOWN DATE: 06/07/04 FIGURE NO.: 6 c s c ' ' ~· .... :-7, •.• ~ \ ·:::: ....... . ,' : ...... <:; j I KEY PROP. BUILDINGS -0.39 ac. PROP. PAVEMENT-1.08 ac. PROP. GRASS AREAS -0.93 ac. UNIVERSITY DRIVE ~~~~\\~\\\\l\~r~=/·::~~w::·-· :~rt· - ::~~\~;:"} ::: ~~~r~11~1~~111111~~l1~l'~~~N~O!T!E~~~~~~ ! INFORMATION PRESENTED IN THIS DRAIMNG IS or: FOR INFORMATIONAL PURPOSES ONLY AND NOT INTENDED TO BE USED IN CONSTRUCTION. 60 0 bf=?..---E4 PROJECT: AMERISUITES HOTEL 60 I FEET I llJ:tn1·1·r111g ,\:I ff'tro!llll( 11t<1f ( (111\llliiJfll\bl< TYPES OF SITE COVER MATERIAL AMERISUITES HOTEL KYLE LEGENDS I, LP LOCATION: COLLEGE STATION TEXAS APPR: MFC REV. DATE: DRAWN BY: JBF SCALE: AS SHOWN ATE: 06/07.Q4 FIGURE NO: 7 c s c VI -<J 0 w (.!) ~ < :r: u (/) i5 tn/ltitle~ri'JZ & Em·mJm:tJ:mal Comu!tm'tls, /Ju:. 45 40 35 30 25 20 15 10 5 0 0 POST • 21.5 cf1 0 PRE • 14.8. cts 0 II .!I 10 (600 sec.) PRE AND POST DEVELOPMENT HYDROGRAPHS FOR 100-YEAR STORM EVENT AMERISUITES HOTEL COLLEGE STATION TEXAS Minumum Volume of Oelentton St0toqe Bosin • Difference In At'eos Between Pre ond Pott Oevetopment Hydr09roph1 15 TIME 20 ( 1200 sec.) re pare or: KYLE LEGENDS I, LP 25 30 min. (1800 sec.) PROJECT: AMERISUITES HOTEL LOCATION: COLLEGE STATION TEXAS -CD CD ~ () :c ::::J () ..... :::E => _J 0 > ..... (.!) 4 0::: 0 I- (/) ..... > ~ ~ => :::E => u I 9,000 B,000 Eme~~ Spill wall eve I Volume • 7,400 cu ft.- 7,000 6,000 5,000 4,000 3,000 2,000 1,000 0 (£1..•2117.00) 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 (£1..•2117J50) (El..•2811.00) (El..-2llllJ50) (£1..•2111.00) (£1..•28tJ50) (£1..-290.00) (£1..•290.80) (£1..•291.00) (£1..•291J50) (n.-292.00) c s c l.11gi11~e1 ing & l.nvilo11mentol Co11r11/1011t5,/11c or: KYLE LEGENDS I, LP Depth, feet (Elevation, mis) STORM WATER DETENTION BASIN DEPTH VS. STORAGE VOLUME AMERISUITES HOTEL PROJECT: AMERISUITES HOTEL LOCATION: COLLEGE STATION, TEXAS APPR: MFC REV. DATE: DRAWN BY: JBF SCALE: AS SHOWN DATE: 06/07/04 FIGURE NO.: 9 z 0 I-z w I-w 0 2 0 0:::: LL (/) . (j) '+-; s u 0 _J .. LL GJ _J WI- l? :J 0:::: 0 <{ I Z u-(j) (j) _<{ om 10 8 6 4 2 0 / 11g11u•trJ1tg ,\ f 11'/lmmu fllal ( <}ff\ld/11'/h ''" 0.5 1.0 1.5 2.0 2.5 3.0 STORED RUNOFF HEIGHT IN DETENTION BASIN, FT. or. CUMULATIVE OUTFLOWS VS. DEPTH OF STORAGE AMERISUITES HOTEL KYLE LEGENDS I, LP 3.5 4.0 4.5 RISING STAGE --- RECEDING STAGE -- -- PEAK o PROJECT: AMERISUITES HOTEL LOCATION: COLLEGE STATION TEXAS APPR: MFC REV. DATE: DRAWN BY: JBF SCALE: AS SHOWN DATE: 06/07/04 FIGURE NO.: 10 5.0 , ~ ...J LL 0 5 l.11g111een11s & 1:11vi101m1e11tnl Co11s11lwms, fur KYLE LEGENDS I, LP 15 3) TIME (min) Inflow and Outflow Hydrographs Illustrating Routing of 100-Year Storm Event PROJECT: AMERISUITES HOTEL LOCATION: COLLEGE STATION, TEXAS APPR: MFC REV. DATE: DRAWN BY: JBF SCALE: AS SHOWN DATE: 06/07/04 FIGURE NO.: 11