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HomeMy WebLinkAboutDrainage ReportOWN loo Engineer: HARLE ENGINEERING COMPANY P.O. Box 11587 College Station, TX 77842 3002 Texas Avenue South -r College Station, Texas 77845 (979) 693 -7191 Drainage Report for Castle Rock Subdivision Phase 5 College Station, Texas February, 2010 Developer. - Greens Prairie Investors, Ltd. 4490 Castlegate Drive College Station, Texas 77845 (979) 690 -7250 Drainage Report for Castle Rock Subdivision Phase 5 College Station, Texas February, 2010 Engineer: HARLE ENGINEERING COMPANY P.O. Box 11587 College Station, TX 77842 3002 Texas Avenue South College Station, Texas 77845 (979) 693 -7191 Developer: Greens Prairie Investors, Ltd. 4490 Castlegate Drive College Station, Texas 77845 (979) 690 -7250 ENGINEER HARLE ENGINEERING COMPANY P.O. Box 11587 College Station, Texas 77842 Phone/Fax: (979) 693 -7191 OWNER/DEVELOPER Greens Prairie Investors, LLC 4490 Castlegate Drive College Station, Texas 77845 Phone: (979) 690 -7250 Description: • Area: • Proposed Land Use: • # of Lots: • Existing Land Use: • Land Description: Adjoining Land Use: Primary Drainage Facility: Flood Hazard Information: FEMA FIRM.. Floodplain: GENERAL STORMWATER PLAN Castle Rock Subdivision, Phase 5 Drainage Report — Executive Summary GENERAL DESCRIPTION AND LOCATION Location: Castle Rock Subdivision, Phase 5, is located on the north side of SH 40, William D. Fitch Parkway, near its intersection with Castle Rock Parkway. 6.513 acres PDD- Single Family Residential 29 lots Agricultural — consisting primarily of a wooded pasture used for cattle grazing Rolling terrain that falls north toward Spring Creek. The site is heavily wooded. The site is bounded on the south and west by developed sections of the Castle Rock Subdivision, on the north by the future Phase 6 of the subdivision and on the east by a greenbelt. Spring Creek # 48041CO205 D (February 9, 2000) No portion of this Phase lies within the floodplain of Spring Creek or its tributaries. HYDROLOGIC CHARACTERISTICS The existing site is predominately wooded. The elevations range from 281 to 287, sloping generally in a northly direction where the runoff enters tributaries of Spring Creek, which ultimately flow into Spring Creek on the adjacent tracts. The drainage plan for this development will involve the installation of inlets, junction boxes and storm sewer pipes for 2 separate systems, each of which will discharge into existing ditches which are located in the future Phase 6 area of Castle Rock. These ditches are a tributaries of Spring Creek. The system on the west end of the Phase connects to existing storm sewer pipes which are being constructed with Phase 4 which also collects the runoff from existing storm sewer systems constructed with Phases 1A, 2A, 2B and 3. The proposed storm sewer system on the east end of the Phase will connect to a storm sewer pipe constructed with Phase 2A which currently discharges into a existing channel. The detention pond for this proposed development is located downstream of this development, on Spring Creek, adjacent to SH 6, on the Crowley Tract, which is being developed as the Tower Pointe development. Page 1 of 3 COORDINATION & STORMWATER PERMITTING The project will require that a Notice of Intent be submitted to the Texas Commission for Environmental Quality. No other permits are anticipated for this project. DRAINAGE DESIGN General Information: Street Design: T Methodology: 71. Minimum Design Storm Event: Pipe Materials: Manning's n Value: Runoff Coefficients: Design Constraints: Stormwater runoff from Phase 5 of the subdivision will be collected by 2 separate systems which discharge into existing ditches. The system on the west end of the Phase primarily carries the runoff from previous Phases including some of Phase 4 while the system on the east end collects runoff from the east end of Phase 2A and from future development areas of the Subdivision. The location of the drainage areas for evaluation of the gutter depth check, inlet sizing and pipe evaluation are shown on Exhibit A. Also shown are the location of the inlets, junction boxes and storm sewer pipes. In order to not have to construct open channels for the storm sewer pipes in Phase 4 to drain into and then fill these channels with the future development of Phases 5 and 6, storm sewer inlets, junction boxes and pipes are being constructed with Phase 4 even though they are located in Phase 5 and Phase 6. The inlets and storm sewer piping required for the street construction on the west end of this Phase is now included with this construction. The system proposed for the east end of this Phase collects the storm runoff from the proposed street and from the existing street in Phase 2A as well as future development areas. Standard cross - section (3% cross - slope, 27' B -B residential) Lay down curb & gutter on residential streets Asphalt pavement Standard recessed curb inlets (5' and 10' in length) TR 55 10 minutes 10 -year - residential street & storm sewer Corrugated HDPE w /smooth interior, RCP, Profile Gasket in accordance with ASTM C443, ASTM C78, Class III 0.013 0.60 for developed lots Max. water depth in curb = 4.0 in. or 0.33 ft. Min. flow velocity = 2.5 fps Max. flow velocity = 15 fps 100 -yr storm runoff maintained within the ROW (4 inches above curb) Design Software: Excel spreadsheets, DODSON HydraCalc Hydraulics This software was used to compute pipe capacity, flowrate and velocity through each pipe, and determine hydraulic grade line elevations at each inlet or junction box. All of this information is shown in the summary tables in Appendix E. Page 2 of 3 Applicable Exhibits: DETENTION DESIGN General: CONCLUSION CERTIFICATION The College Station requirement for a 25% reduction in cross - sectional area of pipes less than 27" diameter is achieved by using internal pipe diameters that are less than the standard diameter. The 24" diameter pipe areas were reduced by 25% and a 20.6" diameter pipe used in the analysis and the 18' diameter pipe areas were reduced by 25% and a 15.6" diameter pipe was in the analysis. Design Results The data presented in the Appendices indicates the gutter depth, inlet sizing and pipe sizes are in accordance with the requirements of the design guidelines. Exhibit A — Drainage Area Map Appendix A — Technical Design Summary Appendix B — Drainage Area Calculations Appendix C — Depth of Flow in Gutter Summary Appendix D — Inlet Design Summary Appendix E - Pipe Design Summary Stormwater runoff from Phase 5 and all previous and subsequent phases of the Castle Rock Subdivision flow into Spring Creek upstream of the regional detention facility constructed in 2001. This facility was designed to control stormwater releases from the Castle Rock Subdivision and other adjoining properties. No additional detention facilities are provided with the development of this project. Based on the concurrence with the previous design calculations from Phases 1A, 2A, 2B, 3 and 4, the drainage system in Phase 5 of the Castle Rock Subdivision will function within the requirements and restrictions of the College Station Drainage Policy and Design Standards. I, Joseph P. Schultz, Licensed Professional Engineer No. 65889, State of Texas, certify that this report for the drainage design for Castle Rock Subdivision, Phase 5, was prepared by me in accordance with the provisions of the Unified Stormwater Design Guidelines. Jos ' • h P. r: chultz, P.E. Page 3 of 3 d JOSEPH P. SCHULTZ 4-p% 65889 tl'UG ge w� i? m / c r i'd t�5 t 2 /C 4 1 0 APPENDIX A Technical Design Summary Part 2 — Protect Administration Start (Page 2.1) ` " Engineering and Design Professionals Information Engineering Firm Name and Address: R vie r-4.1 h ee(4- Fjr'^^ do t (.58 C o l k 5`1 L - ;,,,„ I -r n ( 7 � 4 S Jurisdiction City: Bryan ✓ College Station Date of Submittal: re le r..<ey 2010 Lead Engineer's Name and Contact Info.(phone, e-mail, fax): Joseet l P- 5 -E,PC 691.7) S/ . # 6 79. 1/ fl jap5eArl+e kJ cr.zih. Other: f Supporting Engineering / Consulting Firm(s): Other contacts: Developer / Owner / Applicant Information Developer / Applicant Name and Address: Grerrs Pro. rfe ►1vr5A - trS, L - 44 q Cost k 6�e e 1 C. f. 7 7�?3f5 Phone and e-mail: �,9J -7ZS- W 61 1��,�h'1f -�s� L Property Owner(s) if iiot Developer / Applicant (& address): 50 Of /3 ' Phone and e-mail: — Project Identification n Development Name: C c f •f-) t k . 516 d• v f'e r I" k e,S e 5 Is subject property a site project, a single -phase subdivision, or part of a multi -phase subdivision? 14I w14-r — 1 11O5 e If multi - phase, subject property is phase 6 of ' . Legal description of subject property (phase) or Project Area: (see Section II, Paragraph B -3a) . S�3 s 6 , k— o� -- -e 2e b-�/ - S ry st r, 5v /v-ci, A 41 If subject property (phase) is second or later phase of a project, describe general status of all earlier phases. For most recent earlier phase Include submittal and review dates. (" h of t 4 u tr.cl-a-r CtJh a/ 'e `.. . General Location of Project Area, or subject property (phase): 14 : 1,.' per\ o. e�e- I-. PkO ft L S (tit-L,.. In City Limits? Bryan: acres. Extraterritorial Jurisdiction (acreage): Bryan: College Station: College Station: ra • SI 3 acres. Acreage Outside ETJ: — SECTION IX APPENDIX D — TECHNICAL DESIGN SUMMARY STORMWATER DESIGN GUIDELINES Page 3 of 26 APPENDIX. D: TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 Part 2 — Project Administration Continued (page 2.2) Project Identification (continued) Roadways abutting or within Project Area or subject property p� W(�►�, � ` ;*� t a, w ccfr rPAk -WI Abutting tracts, platted land, or built developments: 4 P `h o3e5 4 A--/ Z 4 Na Regulatory Watercourse(s) & Watershed(s): A) ISM i: Oct; '4- 1"trefc Tributary Basin(s): 5IV , 1 *-4 C r r -A Plat Information For Project or Subject Property (or Phase) Preliminary Plat File #: 5 D 0 b b 6 Final Plat Status and File #: — Date: Name: C ci fi, ( .k Srbd:vf VoI /Pg: Si4►n- Ile.) Z"/o -/a If two plats, second name: Status: File #: Date: Zoning Information For Project or Subject Property (or Phase) Zoning Type: J'el Ej Case Date Status: Proposed? Case Code: Zoning Type: Existing Case Date Status: or Proposed? Case Code: Stormwater Management Planning For Project or Subject Property (or Phase) Planning Conference(s) & Date(s): Participants: Preliminary Report Required? N A Submittal Date Review Date Review Comments Addressed? Yes r'% No In Writing? When? Compliance With Preliminary Drainage Report. Briefly describe (or attach documentation explaining) any deviation(s) from provisions of Preliminary Drainage Report, if any. N ;Pr SECTION IX APPENDIX D — TECHNICAL DESIGN SUMMARY STORMWATER DESIGN GUIDELINES Page 4 of 26 APPENDIX. D: TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 Part 2 — Project Administration Continued (page 2.3) Coordination For Project or Subject Property (or Phase) Note: For any Coordination of stormwater matters indicated below, attach documentation describing and substantiating any agreements, understandings, contracts, or approvals. Coordination With Other Departments of Jurisdiction City (Bryan or College Station) Dept. Contact: Date: Subject: N/� Coordination With Non jurisdiction City Needed? / Yes No �/ Summarize need(s) & actions taken (include contacts & dates): Coordination with Brazos County Needed? Yes No Summarize need(s) & actions taken (include contacts & dates): Coordination with TxDOT Needed? Yes No V Summarize need(s) & actions taken (include contacts & dates): Coordination with TAMUS Needed?/ Yes No V Summarize need(s) & actions taken (include contacts & dates): Permits For or Subject Property (or Phase) As to stormwater management, are permits required for the proposed work from any of the entities listed below? If so, summarize status of efforts toward that objective in spaces below. Entity Permitted or ? Status of Actions include dates) Actions ( include US Army Crops of Engineers ' / No Yes �/ y �o v J N F,,.4kr ffG'' .. ) Pta i e r- �-"-1 f l e t oil I E/ rte : . US Environmental Protection Agency No if Yes Texas Commission on Environmental Quali ..y No Yes ay .y G ! n r�`r' «r.-4- (Spoon MIT-- cr 1 r7c 1C Li b, / J� �� �qq (f- h fie i C evi-r r/ a/ Brazos River Authority No .✓ Yes et Psi f SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D — TECHNICAL DESIGN SUMMARY Page 5 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2009 Part 3 — Property Characteristics Start (Page 3.1) Nature and Scope of Proposed Work Existing: Land proposed for development currently used, including extent of impervious cover? N Ere - li d t Gri- f Site Development Project (select all applicable) n/ / 4. Redevelopment of one platted lot, or two or more adjoining platted, lots. Building on a single platted lot of undeveloped land. Building on two or more platted adjoining lots of undeveloped land. Building on a single lot, or adjoining lots, where proposed plat will not form a new street (but may include ROW dedication to existing streets). Other (explain): Subdivision Development Project Construction of streets and utilities to serve one or more platted lots. _Construction of streets and utilities to serve one or more proposed Tots on lands represented by pending plats. Describe Nature and Size of Pro s osed Site proiects: building use(s), approximate floor space, impervious cover ratio. Subdivisions: number of lots by general type of use, linear feet of streets and drainage easements or ROW. 'L i 1 S _. . I a � (5 of S�/ c 5 Project Is any work planned on land that is not platted If yes, explain: N or on Ind for which platting is not pending? No Yes P EMA Floodplains Is any part of subject property abutting a Named Regulatory Watercourse (Section II, Paragraph B1) or a tributary thereof? No t/ Yes Is any part of subject property in floodplain area of a FEMA - regulated watercourse? No V Yes Rate Map ¢u o4ILeFoS r Encroachment(s) into Floodplain areas plann ? No Encroachment purpose(s): Building site(s) Road crossing(s) Utility crossing(s) Other (explain): ,J1 Pr Yes If floodplain areas not shown on Rate Maps, has work been done toward amending the FEMA- approved Flood Study to define allowable encroachments in proposed areas? Explain. / SECTION IX APPENDIX D — TECHNICAL DESIGN SUMMARY STORMWATER DESIGN GUIDELINES Page 6 of 26 APPENDIX. D: TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 Part 3 - Property Characteristics Continued (Page 3.2) Hydrologic Attributes of Subject Property (or Phase) Has an earlier hydrologic analysis been done for larger area including subject property? Yes Reference the st (& date) here, and attach copy if not already in City files. c 1.... b r'\g — 1-J 14__ ' �1'tQ.wtGi i.. - Zoa L_0 rh t2 - w w P. o an J 4 Also c j Zoo , Is the stormwater earlier study? manage plan for the property in substantial Yes V No If not, explain how conformance with the it differs. No If subject property plan for the is not part of multi -phase project, describe stormwater management property in Part 4. If property is part of multi -phase project, provide overview of stormwater management plan for Project Area here. In Part 4 describe how plan for subject property will comply therewith. 4/ Do existing topographic features on subject property store or detain runoff? Describe them (include approximate size, volume, outfall, model, etc). 1/ No Yes Any known drainage or flooding problems in areas near subject property? Identify: No Yes Based (see Table on location of B -1 in Appendix Detention is required. study property in a watershed, is Type 1 Detention (flood c ntr9j) nee ed,? B) Ir '1 e,o�p ( Y %�✓ Need must be evaluated. t" not required. If the need for Type 1 Detention must be evaluated: What decision has been reached? By whom? How was determination made? --- SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D - TECHNICAL DESIGN SUMMARY Page 7 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2009 Part 3 — Property Characteristics Continued (Page 3.3) Hydrologic Attributes of Subject Property (or P Ja se) (continued) Does subject property straddle a Watershed or Basin divide? V No Yes If yes, describe splits below. In Part 4 describe design concept for handling this. Watershed or Basin Larger acreage Lesser acreage Above - Project Areas(Section II, Paragraph B3 -a) Does Project Area (project or phase) receive runoff from upland areas? V No Yes Size(s) of area(s) in acres: 1) 2) 3) 4) Flow Characteristics (each instance) (overland sheet, shallow concentrated, recognizable concentrated section(s), small creek (non-regulatory), regulatory Watercourse or tributary); �. se 5- / _ -s •ue PL sJts Z 19 4 �� � spec /w . c c by -V ,,,.....0 +�j4' ', e k e e Flow determination: Outline hydrologic methods and assumptions: r y�.� C -efi . , E t ek�h f J r.A, f ((V ;J -1 p 1 `Je ! I — we Ul hJ'--t ("V`n_o`- Does torm runoff drain from public easements or ROW onto or across subject property? V No Yes If yes, describe facilities in easement or ROW: Are changes in runoff characteristics subject to change in future? Explain Ai O Conveyance Pathways (Section II, Paragraph C2) Must runoff from study property drain across lower➢roperties before reaching a Regulatory Watercourse or tributary? No ii// Yes Describe length and characteristics of each conveyance pathway(s). Include ownership of property(ies). , . + l P w S a� 'I ,� �� . � jr-•:,..3t of shr 4—r e O'c % s f 4C C - of C, -e e s `-``6 "' - SECTION IX APPENDIX D — TECHNICAL DESIGN SUMMARY STORMWATER DESIGN GUIDELINES Page 8 of 26 APPENDIX. D: TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 Part 3 — Property Characteristics Continued (Page 3.4) Hydrologic Attributes of Subject Property (or Phase) (continued) Conveyance Pathways (continued) Do drainage easements exist for part of path tr any (s)? No Yes If yes, for what part of length? % Created by? plat, or instrument. If instrument(s), describe their provisions. Pathway Areas Where runoff property(ies). G .' , _ � � must cross lower properties, describe characteristics (Existing watercourses? Easement or Consent 1 owns p lee (7) �� b e USA :cf /Pavc1 111- of abutting lower aquired ?) dA 74 Ccn ''`7 S evv\ ,Sew - "i CRIr ‘ t 4. riser Sher"∎ c `T re 6e-i. S ,j,I, C.rt.lc. Nearby Drainage Facilities Describe any built or improved drainage facilities existing near the property (culverts, bridges, lined channels, buried conduit, swales, detention ponds, etc). (�% 7L , Vi) , .-1 5 <Fo r Se vv t/' S C ry `,"∎ P <<v1oN$ C c• Do any of design? these have hydrologic or hydraulic influence on No (/Yes If yes, explain: proposed stormwater ,,,;t1 c c��r.ds / -e l (-,,.,, se WV , SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D — TECHNICAL DESIGN SUMMARY Page 9 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2009 Part 4 — Drainage Concept and Design Parameters Start (Page 4.1) Stormwater Management Concept Discharge(s) From Upland Area(s) If runoff accommodate flow section, S o ,fe 5 4.1. pnt ft is to be received from upland areas, what design drainage features will be used to it and insure it is not blocked by future development? Describe for each area, discharge point if or f ,. o n j c / i s $ 1/7 J-1 e sr 4) , .. a 4..0— I _ q /J.• o u s..t, ..ph e...., Jr w.v <r fi S.k...n - Co C •.. Orct /A -$ I' ./r r. � �t I_ (' / k f Pt(- e os'� e,.d o r/ 1 D 1 • ei c wt( be eth . . �- . /4 7" 7 S • Discharge(s) To Lower Property(ies) (Section II, Paragraph El) Does project inc a drainage features (existing or future) proposed to become public via platting? V No Yes Separate Instrument? No Yes Per Guidelines reference above, how will runoff be discharged to neighboring property(ies)? Establishing Easements (Scenario 1) Pre - development Release (Scenario 2) Combination of the two Scenarios Scenario 1: If easements are proposed, describe where needed, and provide status of actions on each. (Attached Exhibit # ) � si c n er/ rl re .tits '� C . ` / "I r‘ p fOrot Scenario 2: Provide general description of how release(s) will be managed to pre - development conditions (detention, sheet flow, partially concentrated, etc.). (Attached Exhibit # ) Combination: If combination is proposed, explain how discharge will differ from pre - development conditions at the property line for each area (or point) of release. If Scenario 2, or Combination are to be used, has proposed design been coordinated with owner(s) of receiving property(ies)? No Yes Explain and provide documentation. SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D — TECHNICAL DESIGN SUMMARY Page 10 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2009 Part 4 — Drainage Concept and Design Parameters Continued (Page 4.2) Stormwater Management Concept (continued) Within Project Area Of Multi -Phase Project Will project result in shifting runoff between Basins or between Water eds? No Identify gaining Basins or Watersheds and acres shifting: What design and mitigation is used to compensate for increased runoff from gaining basin or watershed? Yes How will runoff from Project Area be mitigated to pre- development conditions? Select any or all of 1, 2, and /or 3, and explain below. 1. With facility(ies) involving other development projects. 2 Establishing features to serve overall Project Area. 3. On phase (or site) project basis within Project Area. 1. Shared facility (type & locafon of facility; design drainage area served; relationship to size of Project Area): Exhibit # ) �/ n, I /� L Q� (Attac ��OJ� hed 0'CY��:o.n 1 � ± f cocci-cc) �Oe �( O wl 1'D�r r r r� 1 or ,wl �OWr54 ( - Ccw. aT i ' D�o�Ce.� G�jlGc. s .1 2. For Overall Project Area (type & location of facilities): (Attached Exhibit # ) C to w-1 e1 l /ti C - rb uv-Ci- / �l e \ 1 /.r"�i,.� to/� ., o e/ y/ 3. By phase (or site) project: Describe planned mitigation measures for (or sites) in phases subsequent questions of this Part. 0- m N V- No aquatic echosystems proposed? V No Yes In which phase(s) or project(s)? CU o- co c rn N O 0 Are other Best Management Practices for reducing stormwater pollutants proposed? No V Yes Summarize type of BMP and extent of use: y . //� /[ 1 / _r �j sr 1-1- / � p' c e / Cf) -t l v v d- y � 7 /e e a rh .�/ co I 2 Q If design of any runoff - handling facilities deviate from provisions of B -CS Technical Specifications, check type facility(ies) and explain in later questions. Detention elements Conduit elements Channel features Swales Ditches Inlets Valley gutters Ouffalls Culvert features Bridges Other SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D — TECHNICAL DESIGN SUMMARY Page 11 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2009 Part 4 — Drainage Concept and Design Parameters Continued (Page 4.3) Stormviwater Management Concept (continued Within Project Area Of Multi -Phase Project (continued) Will Project Area include bridge(s) or culvert(s)? ✓ No Yes Identify type and general size and In which phase(s). If detention /retention serves (will serve) overall Project Area, describe how it relates to subject phase or site proje h ical location, conveyance a pathway(s), construction sequence l: -0,, r„„,' ri lOw. e LlsH de- e- r-,.-- <sfill • elf d/ C 6 rK n I l 4.- /0 2 CLW"'"1 �y c , l /y • Within Or Serving Subject Property (Phase, or Site) If property part of larger Project Area, is design in substantial conformance with earlier analysis and report for larger area? ✓Yes No, then summarize the difference(s): Identify whether each of the types of drainage features listed below are included, extent of use, and general characteristics. Typical shape? Surfaces? ditches use Yes Steepest side slopes: Usual front s opes: Usual back slopes: Flow line slopes: least Typica distance from travelway: (Attached Exhibit # ) typical greatest Are longitudinal culvert ends in compliance with B -CS Standard Specifications? Yes No, then explain: At intersections or otherwise, do valley gutters cross arterial or collector streets? V No Yes If yes explain: eets with c. 3utterused' Jo �' Are/alley gutters proposed to cross any street away from an intersection? No Yes Explain: (number of locations ?) SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D — TECHNICAL DESIGN SUMMARY Page 12 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2009 Part 4 – Drainage Concept and Design Parameters Continued (Page 4.4) Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, or Site) (continued) �. a) = D 0 Q c E t g ED. IA iu Gutter line slopes: Least O. & '7 Usual ( . O Vo Greatest 1 •9 ? Are inlets recessed on arterial and collector streets? Yes No If "no ", identify where and why. N //4 Will inlets capture 10 -year designstormflow to prevent with arterial or collector)? V Yes No If flooding of intersections (arterial no, explain where and why not. Will inlet size and placement design storm throughout site c c yi p er d prevent exceeding allowable water (or phase)? V Yes spread for 10 -year No If no, explain. ,C G Saq curves: Are inlets placed at low points? Yes No Are inlets and co t sized to prevent 100 Yes No Explain -year stormflow from ponding at greater than 24 inches? "no" answers. Will 100 -yr stormflow be containepin whole length of all streets? "11 4k Svr-�1.�,� g 's r< e1 c G tiff_ le combination of ROW V Yes No If and buried conduit on no, des ribe were and why. 1 .-4- . F loe G 1 (kr -rit -0 ( — dc^-. o + s . - e4 S444 , icy t s w" -'1 Do designs for curb, gutter, and V Yes No If 1k et re,., ∎, - �:k : Lt - 4... inlets comply with B -CS Technical Specifications? not, describe difference(s) and attach justification. a } aa) N and `L°z E ° co Are any 12 -inch laterals used? used. No Yes Identify length(s) and where Pipe runs between system access points (feet): t Typical so Longest Z S I Are junction boxes used at each why. bend? V Yes No If not, explain where Are down9('ream soffits at or below Yes V No If not, upstream soffits? explain where and why: Least amount that hydraulic grade line is below gutter line (system- wide): 11 1 SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D — TECHNICAL DESIGN SUMMARY Page 13 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2009 Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, or Site) (continued) a u v . c X 00 c E c O c c Ea) >, c_ 2 o a a E 15 i n N III 0 to c 0 .s1 3 O Describe watercourse(s), or system(s) receiving system discharge(s) below (include design discharge velocity, and angle between converging flow lines). 1) Watercourse (or system), velocity, and angle? f ( Ye ..er I SI..... 0a weJF el — e+. „o eec If p-' re 141)•1?.(.. fa ,r r-s tlrr. pf,6 4., e , e,c(f a1/.cL‘ - eet /0661fe%e %�; le 2) Watercourse (or system), velocity, and angle? 5 t ,-,_ ,f l ,,,,m,_ ,C7 fie - 0 'l w"/ 4- 1" — - vAll e,c- 's f i,� 41:1-tie‘ 3) Watercourse (or system), velocity, and angle? For each outfall above, what measures are taken to prevent erosion or scour of re and all facilities at juncture? 1) jbk. , "l o P.” Lir•'rf Or ://-4-) �4.1 r � 1 J a v 2 r e of. .e£ ^ill.?( p' '�c 2 ) / �` / 4) it. �� •- Z • ,-, (04 e S t d (ry --.5 j 1 c," .� • 1/ e l oc :Li : -"N rr /k 4 •41 ( 5 L G ' Cr s. cs- a) m u) an } c m 00 4 ) y I N ¢` I 0 Are swale(s) Number situated along property lines between properties? No Yes of instances: For each instance answer the following questions. Surface treatments (including low -flow flumes if any): Flow line slopes (minimum and maximum): Outfall characteristics for each (velocity, convergent angle, & end treatment). Will 100 ROW -year design storm runoff be contained within easement(s) or platted drainage in all instances? Yes No If "no" explain: SECTION IX Part 4 — Drainage Concept and Design Parameters STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D — TECHNICAL DESIGN SUMMARY Continued (Page 4.5) Page 14 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2009 Part 4 - Drainage Concept and Design Parameters Continued (Page 4.6) Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, r Site) (continued) Roadside Ditches Are roadside ditches used? V No Yes If so, provide the following: ? Yes No Is 25 -year flow contained with 6 inches of freeboard throughout Are top of banks separated from road shoulders 2 feet or more? Are all ditch sections trapezoidal and at least 1.5 feet deep? Yes No Yes No For any "no" answers provide location(s) and explain: (on separate sheet provide same information for any additional instances) If conduit is beneath a swale, provide the following information (each instance). Instance 1 Describe general location, approximate length: Is 100 -year design flow contained in conduit/swale combination? If "no" explain: Yes No Space for 100 -year storm flow? ROW Easement Width Swale Surface type, minimum Conduit Type and size, minimum and maximum and maximum slopes: slopes, design storm: Inlets Describe how conduit is loaded (from streets /storm drains, inlets by type): Access Describe how maintenance access is provided (to swale, into conduit): Instance 2 Describe general location, approximate length: Is 100 -year design flow contained in conduit/swale combination? If "no" explain: Yes No Space for 100 -year storm flow? ROW Easement Width Swale Surface type, minimum Conduit Type and size, minimum and maximum and maximum slopes: slopes, design storm: Inlets Describe how conduit is loaded (from streets /storm drains, inlets by type): Access Describe how maintenance access is provided (to swale, into conduit): SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D - TECHNICAL DESIGN SUMMARY Page 15 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2009 Part 4 — Drainage Concept and Design Parameters Continued (Page 4.7) Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, or Site) (continued) WiII swales without buried conduit receive runoff from public ROW or easements? No Yes. Explain If "yes" provide the following information for each instance: Instance 1 Describe general location, approximate length, surfacing: Is 100 -year design flow contained in swale? Yes No Is swale wholly within drainage ROW? Yes No Explain "no" answers: Access Describe how maintenance access is provide: Instance 2 Describe general location, approximate length, surfacing: Is 100 -year design flow contained in swale? Yes No Is swale wholly within drainage ROW? Yes No Explain "no" answers: Access Describe how maintenance access is provided: Instance 3. 4, etc. If swales are used in more than two instances, attach sheet providing all above information for each instance. Chanr,irrrprovements proposed? No Yes Explain "New" channels: Will any area(s) of concentrated flow be channelized (deepened, widened, or straightened) or otherwise altered? No Yes If only slightly shaped, see "Swales" in this Part. If creating side banks, provide information below. Will design replicate natural channel? Yes No If "no ", for each instance describe section shape & area, flow line slope (min. & max.), surfaces, and 100 -year design flow, and amount of freeboard: Instance 1: Instance 2: Instance 3: SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D — TECHNICAL DESIGN SUMMARY Page 16 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2009 Part 4 — Drainage Concept and Design Parameters Continued (Page 4.8) Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, or Site) (continued) Channel Improvements (continued) Existing channels (small creeks): Are these used? No Yes If "yes" provide the information below. Will small creeks and their floodplains remain undisturbed? Yes No How many disturbance instances? Identify each planned location: For each location, describe length and general type of proposed improvement (including floodplain changes): For each location, describe section shape & area, flow line slope (min. & max.), surfaces, and 100 -year design flow. Watercourses (and tributaries): Aside fr /m fringe changes, are Regulatory Explain below. Watercourses proposed to be altered? J No Yes Submit full report describing proposed changes to Regulatory existing and proposed section size and shape, surfaces, alignment, length affected, and capacity, and provide full documentation and data. Is full report submitted? Yes No Watercourses. Address flow line changes, of analysis procedures If "no" explain: All Proposed Channel Work: For all proposed channel work, provide information requested in next three boxes. If design is to replicate natural channel, identify location and length here, and describe design in Special Design section of this Part of Report. r \P Will 100 -year flow be contained with one foot of freeboard? Yes No If not, identify location and explain: N \0 ' Are ROW / easements sized to contain channel and required Yes No If not, identify location(s) and explain: maintenance space? 0rl'e SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D - TECHNICAL DESIGN SUMMARY Page 17 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2009 Part 4 — Drainage Concept and Design Parameters Continued (Page 4.9) Stormwater Management Concept (continued) ? C trb..1" ow (-_ Within Or Serving Subject Property (Phase, or Site) (continued) ` s � ,d -4, r r e , j 1 How many facilities for subject property project? For each provide info. below. For each dry-type facilitiy: Faci ity 1 Faci ity 2 Acres served & design volume + 10% 100 -yr volume: free flow & plugged Design discharge (10 yr & 25 yr) Spillway crest at 100 -yr WSE? yes no yes no Berms 6 inches above plugged WSE? yes no yes no Explain any "no" answers: For each facility what is 25 -yr design Q, and design of outlet structure? Facility 1: Facility 2: Do outlets and spillways discharge into Facility 1: Yes No a public facility Facility 2: in easement Yes or ROW? No If "no" explain: For each, what is velocity of 25 -yr design discharge Facility 1: & Facility at outlet? & at spillway? 2: & Are energy dissipation measures used? location: No Yes Describe type and For each, is spillway surface treatment other than concrete? Yes or no, and describe: Facility 1: Facility 2: For each, what measures are taken to prevent erosion or scour at receiving facility? Facility 1: Facility 2: If berms are used give heights, slopes and surface treatments of sides. Facility 1: Facility 2: SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D — TECHNICAL DESIGN SUMMARY Page 18 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2009 Part 4 — Drainage Concept and Design Parameters Continued (Page 4.10) S tormwater M anagement Concept (continued) Within Or Serving Subject Property (Phase, or Site) (continued) Detention Facilities (continued) Do structures comply with B -CS Specifications? Yes or no, and explain if "no ": Facility 1; N1 Facility 2: For additional facilities provide all same information on a separate sheet. Are parking areas to be used for detention? No Yes What is maximum depth due to required design storm? Are culverts used at private crossings? ■o Yes Roadside Ditches: Will culverts serve access driveways at roadside ditches? V No Yes If "yes ", provide information in next two boxes. Will 25 -yr. flow pass without flowing over driveway in all cases? Yes No Without causing flowing or standing water on public roadway? Yes No Designs & materials comply with B -CS Technical Specifications? Yes No Explain any "no" answers: Are culverts parallel to public roadway alignment? Yes No Explain: Creeks at Private Drives: Do private driveways, drives, or streets cross drainage ways that serve Above - Project areas or are in public easements/ ROW? No Yes If "yes" provide information below. How many instances? Describe location and provide information below. Location 1: Location 2: Location 3: For each location enter value for: 1 2 3 Design year passing without toping travelway? Water depth on travelway at 25 -year flow? Water depth on travelway at 100 -year flow? For more instances describe location and same information on separate sheet. SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D - TECHNICAL DESIGN SUMMARY Page 19 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2009 Part 4 — Drainage Concept and Design Parameters Continued (Page 4.11) Stormwater Management Concept, (continued) Within Or Serving Subject Property (Phase, or Site) (continued) il c Named Regulatory Watercourses (& Tributaries): Are culverts proposed on these facilities? No Yes, then provide full report documenting assumptions, criteria, analysis, computer programs, and study findings that support proposed design(s). Is report provided? Yes No If "no ", explain: Arterial or Major Collector Streets: Will culverts serve these types of roadways? No Yes How many instances? For each identify the 0 n >- a> .r N c c location and provide the information below. Instance 1: Instance 2: Instance 3: 0 0 m Yes or No for the 100 -year design flow: 1 2 3 E o . Headwater WSE 1 foot below lowest curb top? Spread of headwater within ROW or easement? cm ° •N c 0 ca o c U 0 >,15 (0 0 O o : .0 y m -0 a a) m a N c as y o w 0 m c < �, L E 2 Is velocity limited per conditions (Table C -11)? E any "no" answer(s): Minor Collector or Local Streets: Will culverts serve these types of streets? No Yes How many instances? for each identify the locat and provide the information below: Instance 1: Instance 2: Instance 3: For each instance enter value, or "yes" / "no" for: 1 2 3 Design yr. headwater WSE 1 ft. below curb top? 100 -yr. max. depth at street crown 2 feet or less? Product of velocity (fps) & depth at crown (ft) = ? Is velocity limited per conditions (Table C -11)? Limit of down stream analysis (feet)? Explain any "no" answers: SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D - TECHNICAL DESIGN SUMMARY Page 20 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2009 Part 4 — Drainage Concept and Design Parameters Continued (Page 4.12) Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, or Site) (continued) a-Ci c c 0 0 CO t d All Proposed Culverts: For all proposed culvert facilities (except driveway /roadside boxes. ditch intersects) provide information requested in next eight Do culverts and travelways intersect at 90 degrees? Yes No If not, identify location(s) and intersect angle(s), and justify the design(s): Does drainage way alignment change within or near limits of approaches thereto? No Yes If "yes" identify location(s), culvert and surfaced describe change(s), and justification: Are flumes or conduit to discharge into culvert barrel(s)? No Yes If yes, identify location(s) and provide justification: Are flumes or conduit to discharge into or near surfaced approaches No Yes If "yes" identify location(s), describe to culvert ends? outfall design treatment(s): Is scour /erosion protection provided to ensure long term stability of culvert structural components, and surfacing at culvert ends? Yes No If "no" Identify locations and provide justification(s): Will 100 -yr flow and spread of backwater be fully contained drainage easements/ ROW? Yes No if not, why in street ROW, and /or not? Do appreciable hydraulic effects of any culvert extend downstream neighboring land(s) not encompassed in subject property? "yes" describe location(s) and mitigation measures: or upstream to No Yes If Are all culvert designs and materials in compliance with B -CS Yes No If not, explain in Special Design Section Tech. Specifications? of this Part. SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D - TECHNICAL DESIGN SUMMARY Page 21 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2009 Part 4 — Drainage Concept and Design Parameters Continued (Page 4.13) Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, or Site) (continued) a) rn v m Is a bridge included in plans If "yes" provide the following for subject property project? V No Yes information. Name(s) and functional classification of the roadway(s)? What drainage way(s) is to be crossed? A full report supporting all aspects of the proposed bridge(s) hydrologic, and hydraulic factors) must accompany this summary provided? Yes No If "no" explain: (structural, geotechnical, report. Is the report . Q i Is a Stormwater Pollution Prevention P (SW3P) established for project constr io No Yes Provide a general description of planned techniques: / f reti I re"- CortSf/ti .- el-- 1 /- : � 1 e. JJ et. 4_41". i e If -0,C kJ/NA- ;FS"' 1 Special Designs — Non - Traditional Methods Are a non - traditional methods repli ation, BMPs for water quality, No Yes If "yes" list (aquatic echosystems, wetland -type detention, natural stream etc.) proposed for any aspect of subject property project? general type and location below. Provide full report about the proposed expected benefits. Report must be compromised, and that maintenance solution(s). Is report provided? special design(s) including rationale substantiate that stormwater management cost will not exceed those Yes No If "no" explain: for use and objectives will not of traditional design SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D — TECHNICAL DESIGN SUMMARY Page 22 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2009 Part 4 — Drainage Concept and Design Parameters Continued (Page 4.14) Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, or Site) (continued) Special Designs - Deviation From B -CS Technical Specifications If any design(s) or material(s) of traditional runoff - handling facilities deviate from provisions of B -CS Technical Specifications, check type facility(ies) and explain by specific detail element. Detention elements Drain system elements Channel features Culvert features Swales Ditches Inlets Outfalls Valley gutters Bridges (explain in bridge report) In table below briefly identify specific element, justification for deviation(s). Specific Detail Element Justification for Deviation (attach additional sheets if needed) 1) 2) 3) 4) 5) Have elements been coordinated with the City Engineer or her /his designee? For each item above provide "yes" or "no ", action date, and staff name: 1) 2) 3) 4) 5) Design Parameters Hydrology s t Is a map(s) showing all Design Drainage Areas provided ? Yes No Briefly summarize the ran a of appl' tions male of the Rational F�ormuI : 1 // /� � L M A � K l n top 5 1. dip 0 C � ^ ` / r r1 L J I / C �` // N � / / few f ( d -' What is the size and location of largest Design Drainage Area to which the Rational Formula has been applied? 2.2 '1 acres Location (or identifier): 0 l4 70 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY C Gt-4 EGT' u-t 4reaL STORMWATER DESIGN GUIDELINES Page 23 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2009 Effective February 2007 e 406 - 20,76 Lref Part 4 — Drainage Concept and Design Parameters Continued (Page 4.15) Design Parameters (continued) Hydrology (continued) In making deterpinations for time of concentration, was segment analysis used? No t/ Yes In approximately what percent of Design Drainage Areas? 6 0 % As to intensity- duration - frequency and rain depth criteria for criteria other than those provided in these Guidelines used? identify type of data, source(s), and where applied: deter 'ning V No runoff flows, Yes were any If "yes" For each of the stormwater management features listed below identify the storm return frequencies (year) analyzed (or checked), and that used as the basis for design. Feature Analysis Year(s) Design Year Storm drain system for arterial and collector streets i-lip_ "44 Storm drain system for local streets Id 4' (6 o 10 Open channels /kl/ - NM Swale /buried conduit combination in lieu of channel rr `( Swales le r' Roadside ditches and culverts serving them v if Detention facilities: spillway crest and its outfall ', e Detention facilities: outlet and conveyance structure(s) v r' Detention facilities: volume when outlet plugged t ; Culverts serving private drives or streets r , `, Culverts serving public roadways ri i' Bridges: provide in bridge report. r ' 1 Hydraulics What is the range of design flow velocities as outlined below? Design flow velocities; Gutters Conduit Culverts Swales Channels Highest (feet per second) — '- '' Lowest (feet per second) Streets and Storm Drain Systems Provide the summary information outlined below: Roughness coefficients used: For street gutters: For conduit type(s) HO PC (C 0,01 b 0.014 0,013 I_ tt Coefficients: SECTION IX STORMWATER DESIGN GUIDELINES Page 24 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2009 APPENDIX D - TECHNICAL DESIGN SUMMARY Effective February 2007 Part 4 — Drainage Concept and Design Parameters Continued (Page 4.16) Design Parameters (continued) Hydraulics (continued) Street and Storm Drain Systems (continued) % 1( -Open For the following, are asSGmptions other than allowable per Guidelines? Inlet coefficients? ��// No Yes Head and friction losses No Yes Explain any "yes" answer: In conduit is velocity generally increased in the downstream direction? Are elevation drops provided at inlets, manholes, and junction boxes? Explain any "no" answers: `/ Yes No -— Yes No Are hydraulic grade lines calculated3nd shown for design storm? For 100 -year flow conditions? V Yes No Explain any /Yes No "no" answers: What tailwater conditions were assumed at outfall point(s) of the storm drain system? Identify each location and explain: bf o lSct 0T I , p'19e — ras(W e_ ATP_ l' µ Channels If a HEC analysis is utilized, does it follow Sec VI.F.5.a? Yes No Outside of straight sections, is flow regime within limits of sub - critical If "no" list locations and explain: rliA- flow? Yes No Culverts If plan sheets do not provide the following for each culvert, describe it here. For each design discharge, will operation be outlet (barrel) control or inlet control? Ni Entrance, friction and exit losses: N14 Bridges Provide all in bridge repo, NJ SECTION IX STORMWATER DESIGN GUIDELINES Page 25 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2009 APPENDIX D — TECHNICAL DESIGN SUMMARY Effective February 2007 Part 4 — Drainage Concept and Design Parameters Continued (Page 4.17) Design Parameters (continued) Computer Software What computer software has been used in the analysis and assessment of stormwater management needs and /or the development of facility designs proposed for subject property project? List them below, being sure to identify the software name and version, the date of the version, ,a any applicable patches and the publisher ' l� � C c p l 5 c oof f o >L �,r 6- 6- na / �` �ra ���C t V "( 3 0 — /47 oilr, Fl `� I s f Part 5 — Plans and Specifications Requirements for submittal of construction drawings and specifications do not differ due to use of a Technical Design Summary Report. See Section III, Paragraph C3. Part 6 — Conclusions and Attestation Conclusions Add any concluding information here: , n„eS� S � C,49 oip (le J Gt, ter' /� e y rs ► S cif/'rf v G '1 �� N Attestation Provide attestation to the accuracy and completeness of the foregoing 6 Parts of this Technical Design Summary Drainage Report by signing and sealing below. "This report (plan) for the drainage design of the development named in by me (or under my supervision) in accordance with provisions of the Unified Drainage Design Guidelines for the owners of the property. All required by any and all state and federal regulatory agencies for the improvements have been iss ed or fall under applicable general permits." i 1 Part B was prepared Bryan /College Station licenses and permits proposed drainage AC -\ (..., � 1 0 *: x Oh .. JOSEPH P. SCHULTZ 0 3 . A ie 8 ` i + • t"1. °fir: : • it 1 (Affix Seal) Licens d Professional Engineer State of Texas PE No sB SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D — TECHNICAL DESIGN SUMMARY H a,'4 6 --5. 53 ' � AL 11r 2 i'o - / o Page 26 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2009 APPENDIX B Drainage Area Calculations Area # Area, A (acres) C 10 year storm 100 year storm t (min) 1 (in /hr) Q10 (cfs) 1 100 (in /hr) Q1oo (cfs) 501 1.220 0.60 10.0 8.635 6.32 11.639 8.52 502 0.960 0.60 26.0 5.367 3.09 7.316 4.21 502A 0.520 0.60 10.0 8.635 2.69 11.639 3.63 503 0.350 0.60 10.0 8.635 1.81 11.639 2.44 503A 0.340 0.60 10.0 8.635 1.76 11.639 2.37 504 0.520 0.60 11.5 8.136 2.54 10.979 3.43 505 0.160 0.60 10.0 8.635 0.83 11.639 1.12 505A 0.140 0.60 10.0 8.635 0.73 11.639 0.98 506 0.410 0.60 10.0 8.635 2.12 11.639 2.86 507 1.100 0.60 27.8 5.163 3.41 7.046 4.65 508 1.760 0.60 33.3 4.636 4.90 6.348 6.70 509 0.240 0.60 10.0 8.635 1.24 11.639 1.68 510 0.800 0.60 10.0 8.635 4.14 11.639 5.59 511 0.100 0.60 10.0 8.635 0.52 11.639 0.70 601 0.050 0.60 10.0 8.635 0.26 11.639 0.35 602 0.940 0.60 10.0 8.635 4.87 11.639 6.56 701 2.290 0.60 10.0 8.635 11.86 11.639 15.99 702 0.930 0.60 10.0 8.635 4.82 11.639 6.49 703 0.990 0.60 10.0 8.635 5.13 11.639 6.91 704 0.520 0.60 10.0 8.635 2.69 11.639 3.63 801 1.880 0.60 10.0 8.635 9.74 11.639 13.13 802 1.570 0.60 23.1 5.739 5.41 7.808 7.36 803 1.860 0.60 10.0 8.635 9.64 11.639 12.99 Castle Rock Subdivision - Phase 5 Drainage Area Summary The Rational Method: Q = CIA Q = Flow (cfs) A = Area (acres) C = Runoff Coeff. I = Rainfall Intensity (in /hr) Brazos County: I = b / (t +d) t = Time of concentration (min) 10 year storm b = 80 d = 8.5 e = 0.763 100 year storm b = 96 d = 8.0 e = 0.730 t, = L /(V *60) L = Length (ft V = Velocity (ft/sec) APPENDIX C Depth of Flow in Gutter Calculations 100 -year storm Freeboard I ft. I L4'0 I 8£'0 I 84'0 1 E9'0 I 64 0 1 44 0 I 0£'0 I 6 Z' 0 1 Z£' 1 o£o I £90 1 4Z0 I ' 11 8 13 MOLT I £0'LBZ £0'L8Z CO' L8Z CO' LBZ 19£' 282.35 J 19£'ZBZ 9£ZSZ 9Z L9Z 9Z 19Z I 9Z'L9Z 9Z 1.8Z Gutter Runoff, Elev. 280.62 I 280.65 I 1 09'09Z 99'09Z r 99 L9 L61BZ 90Z9Z 90Z8Z 46'09Z 96'093 CL 08Z ZO'L93 ld Jeun5 L£'093 280.37 L£'09Z L£' 093 169' L83 69' L93 69'L83 69' 1.93 280.60 280.60 09'08Z 280.60 Top of Curb OL'09Z I 280.70 I OL'09Z I OL' 08Z I ZO'Z8Z I I Z0 'Z93 I 30393 ZO'Z83 I £6'093 I 1 280.93 £6'08Z I 1 280.93 N 0 0) 0 0 -J ✓ w c ▪ W in O o tn to 15. 4 .c d N CL. o > a S N a g t > O a . s 2 . E 0 0 A m o L' jp 1 N rn N V N O N (V co 0 N N co co N 0 N O 0 0) N 0 0 co V 0 0 M Cl 0)) N O 0) N W ((0 N N O) O o (V 0 0 0 0 0) 0 sr co 0 W O N co O 0 O O m C) m 0 O r O O 0 0 0 co 0 0 V C 40 CO O C O m C-- CO sr O N O m co 0 0 O 0 m co 0 CO O rn 8 0 O O N O r 0) O co O ai 0 0 0 0 O co 0 O O 0 N N N m N N O (0 0) N- 6 N n m O N co 0) O 0 0 0 0 O V N 0 0 co O Y7 OD N M 0) O CO N C) O 0) co co 0 co 0 0 W 0 0 N N O 4- O 0 N 01 CO m 0 0 0 co n o co 0 tV N O 0- M O co co O r N N O 0 Ci O l O N co 0 O O 0 N N CO O co O N LO ui O CA O C O 0 0 0 a, O 0) m 0 0 C) LO N CA O C) O O 0- M co O 0 co 0 O 0 N O O C) C O N N 0 0 0 0 0 N N m c U N Laydown Curb - 10-yr storm max design depth - 4" Castle Rock Subdivision Solved to find actual de 7' street = 0.0330 506, 505A, 503A ht Crown Flow 100-year storm 10-year storm th of flow In APPENDIX D Storm Sewer Inlet Design Summary Castle Rock Subdivision - Phase 5 Storm Sewer Inlets in Sump - Design Analysis Inlet Length Q10 D10 D10 Q100 D100 D100 No. ft. cfs ft. in. cfs ft. in. 407* 5 4.57 0.486 5.83 6.35 0.605 7.26 408 5 0.98 0.174 2.09 1.33 0.213 2.56 501 5 1.76 0.257 3.09 2.37 0.314 3.77 502 10 9.04 0.482 5.79 12.29 0.592 7.10 503 10 7.49 0.425 5.10 10.17 0.521 6.26 504 10 6.58 0.390 4.68 8.87 0.476 5.71 * Includes bypass flow from upstream inlets on grade Assume 10% clogging for design APPENDIX E Storm Sewer Pipe Design Summary !Time (min) • Z9'0 I 9Z'0 OL'0 I 14'0 I 0 1'0 I 140 I 91'0 1 900 1 CVO 1 Lz 1 410 I 900 I L£ 9l op ISM I Sz co ZL I op c•P V (fps) I 6'L I 0'9 I 0 '9 I 0' 9 I 0 0'OL I (OL 1 1 £ OL 1 L8 L9 L9 8'9 (no) OLo 90'99 16'4 84'6 00'91 00'£1 90'94 49 Z4 1 1 91'64 49'99 L VE9 I Z6'Z9 L8'44 taus!) 0LI I 691'9 I 9E9'9 I 9E9'9 I 9£9'8 I 9E9'9 I 559'5 I 009'9 I 0959 £L9'9 999'4 I OE9'9 £L9'9 (uPu) 3 .1. 1 OL'Ez 01:10 0'0 L I oo'ot 1 00'01 I UTZ I £L'4Z I 6Z•4Z 4E'4Z L4'4Z 89'42 L9'4Z I 0 1 09'0 1 09'0 1 09'0 1 09'0 I 09'0 I 09'0 I 0 9 ' 0 09'0 090 090 09'0 09'0 Contributing Pipes 8 - Zd I 8 'L Existing P2 -6, Existing P2 -7, I Existing P -8 P503, P504, P2 -6, P2 -7, P2 -8 P505, P503, P504, P2 -6, P2 -7, P2- 8 IP506, P505, P503, P504, P2 -6, P2 7, P2 -8 I P507, P506, P505, P503, P504, P2 -6, P2 -7, P2 -8 P508, P507, P506, P505, P503, P504, P2 -6, P2 -7, P2 -8 I P609, P508, P507, P506, P505, P503, P504, P2-6, P2 -7, P2-8 1 P610, P609, P508, P507, P506, P505, P503, P504, P2 -6, P2 -7, P2 8 Contributing Area (Acres) I 08L'OL I 096'0 I 0£8' L I OLSZ I OLSZ I 069'ZL I 069'ZL 099'41 096'9L 096'91 096'91 I 068'91 Contributing Drainage Areas Future Phases ZO9 503, 502A, 502 505, 504, 503, 502A, 502 505, 504, 503, 502A, 502 Future Phases, 505, 504, 503, 502A, 502 Future Phases, 505, 504, 503, 502A, 502 507, 506, 505A, 503A, Future Phases, 505, 504, 503, 502A, 502 I 501, 601, 507, 506, 505A, 503A, Future Phases, 505, 504, 503, 502A, 502 I 501, 601, 507, 506, 505A, 503A, Future Phases, 505, 504, 503, 502A, 502 I 501, 601, 507, 506, 505A, 503A, Future Phases, 505, 504, 503, 502A, 502 602, 501, 601, 507, 506, 505A, 503A, Future Phases, 505, 504, 503, 502A, 502 a. N 0 0 e l ' 09,0 I L9'0 I 04'0 1 04' I 09'0 1 00'1 100 1 00'l 09'0 1 09'0 I 09'0 I 09'0 I L 0 -J 06'L6Z 0£'61 00'19 100'4Z L 109'8Z 1 06'94Z 1 09'£6 1 00'19 1 0449 1 09'101 I OL'OL I 00'9Z I 0 N C G. a'vo '-- I 9E I 4Z I 4Z 1 9£ I 9£ 9£ Z4 Z4 Z4 1 Z4 I a s z ° OD a r- a f0 a 1 409 1 909 1 909 1 L09 809 609 OL9 I 149 I Storm Sewer Pipe Summary (10-yr Storm) Castle Rock-Phase 5 31 Time I (min) I L6'0 1 9Z0 1 I 01.'0 I 1.4'0 I 01.'0 I £8'0 I 9E 0 I L 1.'0 I 91 0 I 90'0 ZZ'0 80'0 1 as 1 91. 1 to 9Z m 09 CZ n 1.1. ZZ 1 E1 a (sd;) A 00'S 00'9 00'S 00'9 00'9 009 01.'4 09'4 00'9 00'S 04'9 OZ'S (sly) 001.0 1 69'14 OL9 8C71. £51.1. 09'11 09'89 S0'99 Z6'99 Z9'ZL L4'ZL L0'ZL 1 01'91 (i4/ui) 0011 1 8081 6£9'1.1 6E9'1.1. 609'14 6E9'1.1. L69'L 909 L L69'L 689'1 999'1 LESL 6091 (uiw) of 1 oyez 00'01. 00'01 00'01. 00'01 ZL'£Z £1. 6Z'4Z 4E'4Z L4'4Z 99'4Z 1.9 0 090 09'0 09'0 09'0 09'0 09'0 09'0 09'0 09'0 09'0 09'0 09'0 Contributing Pipes 9 - Zd P2 -7, P2 -8 Existing P2-6, Existing P2 -7, Existing P -8 P503, P504, P2 -6, P2 -7, P2 -8 P505, P503, P504, P2 -6, P2 -7, P21 8 P506, P505, P503, P504, P2 -6, P2 7, P2 -8 P507, P506, P505, P503, P504, P2 -6, P2 -7, P2 -8 P508, P507, P506, P505, P503, P504, P2 -6, P2 -7, P2 -8 P609, P508, P507, P506, P505, P503, P504, P2 -6, P2 -7, P2 -8 P610, P609, P508, P507, P506, P505, P503, P504, P2 -6, P2 -7, P2 Contributing Area (Acres) 10.180 096'0 OE8'1. 01,52 1 01.52 I 069'21 069 Z1. 099'41. -1 046'41. 0S6'91. OS6'91. 069'91. Contributing Drainage Areas Future Phases ZOS 503, 502A, 502 I Z0S 'VZO9 '009 '409 'SOS 505, 504, 503, 502A, 502 Future Phases, 505, 504, 503, 502A, 502 Future Phases, 505, 504, 503, 502A, 502 507, 506, 505A, 503A, Future Phases, 505, 504, 503, 502A, 5n2 501, 601, 507, 506, 505A, 503A, Future Phases, 505, 504 5n3 502A 5n2 .___. 501, 601, 507, 506, 505A, 503A, Future Phases, 505, 504 5n3 502A 51 501, 601, 507, 506, 505A, 503A, Future Phases, 505, 602, 501, 601, 507, 506, 505A, 503A, Future Phases, o 6 O V N 0901 190 1 1 040 1 1 040 1 0901 001 1 °°1. I ° °t 050 1 1 0 t c r J 1.06' 1.62 1 00'61 1 0010 1 00'421. 1 o9 9Z 1 06'84Z 09'06 00 LE 1 01.'49 1 107.60 I 01'01 S. P, v !L N 9E 1 81. 1 4Z 1 4Z I 4Z 1 9C 1 1 9E 1 I Z4 1 Z4 1 1 Z4 1 1 Z4 1 a Z E COS 8 L 9 - Zd 409 909 909 LOS 909 609 1 01.9 0 co 0 °. 0) CO 11 11 11 d V N CO 0 In n m co 0 11 11 11 .0 0 d Storm Sewer Pipe Summary (100-yr Storm) Note: 100-Yr TCs set to same values as 10-Yr TCs. The Rational Method: Brazos County: 100 year storm 10year storm e g!!« 0� l;« m m m m E) e g!!« 0� l;« m QZ e g!!« 0� l;« VIM )/ k 00 �� kk CISM )/ k 00 �� kk CISM EXHIBIT A Drainage Area Map