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HomeMy WebLinkAboutFolderDEVELOPMENT SVCS p p-v/ -1ooolf~ SITE PLAN APPLICATION MINIMUM SUBMlTI AL REQUIREMENTS /sne t'lan application completed in full. . . · . _ SI00.00 Application Fee. · _ $100.00 Development Pennit Application Fee. .,.. i N,/lt $300. 00 Public Infrastructure Inspection Fee if applicable. (This fee is payable if ronst:ruction of a public / waterline, sewerline, sidewalk, street or drainage filcilities is involved.) . . ~001 V, Ten (1 O) folded copies of site plan. ~ A copy of the attached site plan checklist with all itcmB checked off or a brief explanation a.s to why they are not Che.eked O'ff. APPLICATION DATA NAMEOFPROJECT ~\./8TT D:;"WTAL ADDRESS -·~t~ll~}-'-JZ-9~CX.,_.._· ~f~gA.--Ll__i_l~~l~G_@D~iAS)~...,;_~~~·___,,....._~~~~­ LEGAL DESCRIPTION lDT l BLOCf:.: z_ . of' 5a0Ttf~0 APPLICANT (Primary Contact for the Project): . Name · <SS-r£\/E, CA M£l~f--d ALA StreetAddress t.?411 0.61\) lf1-~ 01-#-lo°I City D~ __ _ State 11( ZipCode (!??-?:>( E-MailAddress &v-c:V-..\+~~~\yWO.\\.Vltt Phone Number ~LL(-~~-\ tl:J FaxNumba 7J':f-3\tj -\ ~] f PROPERlY OWNER'S INFORMATION: Name UJl lUvky'\;L g'"J;i(Llv~ l \ Street Address 4? \ S S . T?f)~ ·/Aj,g City 130-l f\i\J State Zip Code /("(;{Y2-E-MailAddress ---------- , 1 q l 10--11 · F<OI: Number ------------- ARCHITECT OR ENGINEER'S INFORMATION: Name ~\E:-\{£. C,. ~'\;t ES-\~ street Address m 11 GIBVJ YA-ces 0,s2.L4Ylft City Mv.t8 . state *' _ Zip~ooe 152.--3( E:-Mail~ddress (i1~'vk:£@.-ClV#O.-il . Yler Phone Number 7,l 'f= '3'9~-\\ \.] Fax Numh¢t ·Z,\\l'-sl.Q t-l ~ lJ . OTIIER CONTACTS (Please specify type of contact, i.e. project manager, potential buyer. local contact, etc.) Name N . Street Address-------------City-------- State Zip Code -----E-Mail Address ---------- . Phone Number Fax Number -~-----------sm PLAN APPUCATION I of3 SrrEAPP 04/13/99 @002 · · · Poo CURRENT ZONING B-.JSU"\.~S 5 --Vla.,\;\.v-,k~ 00-Je~~~ct Dt.>f¥t c.+ PRESENTUSEOFPROPERlY~-'f~~~...;....;..;_:__:_~---~---'--~~---~ V ARIANCE(S) REQUESTED AND REASON(S) # OF PAR.KING SPACES REQUIRED ?-0 #OF PARKING SPACES PROVIDED <2. 2= MULTI-FAMILY RESIDENTIAL .Total Acreage ___ _ Floodplain. Acreage __ Housing Units. ___ _ # of 1 Bedroom Units # of 2 Bedroom Units_ # of 3 Bedroom Units # of 4 Bedroom Units FOR Z BEDROOM UNITS ONLY . __ # Bedrooms ~ 132 sq_ ft _ __ # .Bedrooms < 132 sq. ft. COMMERCIAL Total Acreage Building Square Foet 'o/t 20 Floodplain Acreage ti/ A The appli t has pn:pared this application and certifies that the facts stated herein and exhibits attached hereto a tnut and correct Si 3of3 06 /08 /01 15:22 "li'979 764 3496 DEVELOPMENT SVCS ~004 v l. / 2. -ti 3. CJ 0 (J (J 0 0 ~ 4. ~ 5. ef 6. SlJBMII' A!'PLICATIOM AND TfllS LITT CHECKED OFF WrI'H 10 tlOLDED COPIES OF SITE rLAN FOR REVIEW SITE PLAN MINIMUM REQUIREMENI'S (ALL CI1Y ORDINANCES MUST BE MET) INCLUDING BUT NOT LIMITED TO THE FOLWWING: Sheet size -24" x 36" (minimum). A key map (not necessarily to· scale). Title block to include: Name, address. location, and le&aJ. description Name, address. and telephone number of applicant Name, a.ddreSs, and telephone number of developer/owner (if diff~ from applicant) Name, address, and telephone number of architect/engineer (if differs from applicant} Date of submittal Total site area North arrow. Scale should be largest standard engineering scale possible on sheet. Ownership and current zoning of parcel and all abutting parcels. ( €'t:c.GPr. ~'I A'l~ ~l 0. L01S) 'a/ 7. ,, E:rlsting locations of the following on or adjacent tD the subject site: r/ · Streets and sidewalks (R.0.W.). a; Driveways (opposit.e and ~per Driveway Ordinance 1961 ). 13 / Buildings. GI ,, W:Jier courses. ~' Show all casements clearly designating as existing and type (utility •. access, etc.). C3' 100 yr. floodplain and floodway (if applicable) on or adjaceot to the proposed project site, note if there is . /" none oo the site. S' Utilities (noting size and designate as existing) within or adjazent to the proposed site, including building j' transformer locati~. above ground and underground service connections to buildings, and drainage inlets. a Meter locatiom. S£Efµ>.QC NG ~~Topography: (2' max or spct elevations) and other pcrtineat drainage information. (If '4 ~Nt*trtN! plan has~ much information. show ~con arate sheet.} (J,-8. JI Proposed location. type and dimensions of the following.: ~ ~ Phasing. Each phase must be able to stand alone to meet ordinance requirements. W The gross square footage of all buildings and structures and the proposed use of each. If different uSes are to be located· in a single building. show the location and size of the uses within the building. Building / __ separation is a minimu.m of 15 feet w/o additional fire protection. . 'tsf / Setbac.lG. Show building setbacks as outlined in Ordinance 1638 Zoning Ordinance, (Section 7,·Table A). ~ Off-Street parking areas with parking spaces drawn, tabulated, and dimensioned. Minimum parking space is 9' x 20'. or on a perimeter row 9' x 18' with a 2' overhang. Designate number of parking SJl3CCS . / required by ordinance and provided by pJQP-Q.sal. l3 Handicap parking spaces. SITE PI.AN CHECKLIST I of3 ''I -06/08/01 15: 22 fi'979 764 3496 DEVELOPMENT SVCS @005 ~/~'t ~ -P~~ ~~: Raf~ed bnds~pc· isl~~~ .(6;,-~~~ -~) a minimum of l go sq. ft. arc roquircd at both .. : ______ }!_/~ _ el'l(is_qf. every_parltjn~u:Q~.~p~ce arel_comiguous to the end island maybe applied toward the I/ . ~. f ~ ~--m--required 180 sq. ft.). Addition.ally, 1&0 sq. ft. of landscaping for every 15 interior parking spaces must be provided. An required islands must be landscaped or set with decorative pavers, or stamped dyed concrete or other decorative materials as approved_ Drives_ Minimum drive aisle width is 23' with head-in parking oc 20' without parking. Curb cuts. For each proposed curb cut (including drivt=Ways, strcctB, alleys, etc.) locato cOOsting curb cuts on the same opposite side of the street to determine separation distances between existing and proposed curb cuts. Indicate driveway throat length as measured in the Driveway Ordinance_ (~Ordinance 1961 for driveway location and design ~cnts.) Security gates (show swing path and design SpeGS with colors) . Sidewalks (both public and private). Sidewalks are required at time of development if property bas frontage on a street shown on the Sidewalk Master Plan or if the review staff determines the necessity. (Refer to Section 10.2 of the Zoning Ordinance). Medians. Show any and all traffic medians to be constructed on site. Landscape Reserve. A twenty four foot setback from R.O.W. to curb of parking lot is l1:lquired. Pavement may encroach into this 24' reserve by up to 1134 square fret if street.scape requirement can still be met. In no case may the pavement be less than 6' from the property line. Common open spaces sites Loading docks Detention pends GU3!drails Retaining walls All required and other types of fences (a 6' privacy fenoe is required between industrUl/commercial and residential developments as well as between multi-fWwy and single family developments). Site:s for solid waste cootainers ·with screening. Locations of dumpsters are a.cccssible but not visible from streets or residential areas. Gates are discouraged and visual screening is required. (Minimum 12 x 12 pad / • required_) ~ Show all easements cle.l!ly desigmting as proposed and type (utility, access, etc.). If dedicated by seruatc / instrument list by volume and page. 8 Utilities (noting size and designate as proposed) within or adja.ceat to the proposed site, including building I · t:ransfonner locations, above ground and underg.ro'und service conneaions to buildings. g /' Meter I~ (must be located in public R.O.W. or public utility easement.). . . 13' ;-Proposed grading ( l' max for proposed or spOt elevations) and other pertinent drainage information. (If , ... 'r":,.. ~1 · · , / plan has too much information, show drainage on separate sheet) 6 Show propose.cl and existing'fire hydrants. Fire hydrants must be located on the same side of a major street as a project, and sh.all t>e' in a location approved by the City Enginea. Any strucrure in any rolling district other than R-1, R·lA, or R-2 must be within 300 feet ofa fire hydrant as measured along a public strect, fl/A D highway or dcsigoated fire lane_ Show fire department connections. FDC's should be within 150' of the fire hydrant_ In no case shall they be any further than 300' apart, and they shall be accessfble from the parking lot without being blocked by / · parked cars or a structure. 'a Show fire lanes. Fire laneS a minimum of20 feet in width with a minimum height clearance of 14 fret must be established if any portion of the proposed structure is more than 150 feet from the curb line or pavement NOTE: edge of a public ~or hi_ghway. ··· · Fire hydrants must be operable and accepted by the City, and drives must have an all weather surface as defined in the Zoning Ordinance Section 9 before a building permit can be issued. ~ 9. Will building be sprinkled? Yes CJ No~ If the decision to sprinkle is mM.e after the site plan has been approved, then the plan must be resubmitted. 10. Wheelstops may be required when cars overhang onto property not owned by the applicant or where there may be conflict with handicap acccssible routes or above ground utilities, signs or other contlicts_ ; .. . 06/08/01 15: 23 'Zl'979 764 3496 DEVELOPMENT SVCS 14J006 '/. t:f-11. Show curb and pavement detail. A 6" raised curb is required around all edges of all parts of all paved areas without exception. (To include island. planting areas, acc.ess ways. dumpster locations, utility pads, etc.) Curb details may be found in the Zoning Ordinance Section 9 and alternatives to those standards must be approve:d by the City Engineer. No exception will be made for areas designated as "n;scrved for future 5Eh lJ'rt.f~fln.I) parking". \if. 12. ~Cift'H~p~.as required in Section 11 of the Zoning Ordinance (See Ordinance N 1638.) The landsc3ping plan can be shown on a separate sheet if too much information is on the original site plan. Ifn:questing protected tree points, then those trees need to be iliown appropriately barricaded on the landscape plan. Attempt to m:iuce oc eliminate phu:rtings in easements. Include information on the pl.ans such as: required point calculations additional streetscape points required. Streetscape compliance is required on all streets larger than ~ residential street. calculations for # of street trees required and proposed (proposed street me points will accrue toward total landscaping points.) proposed new plantings with points earned proposed locatioos of new plantings scn:ening of parlcing lots scrocning of dumpsters, detention pends, transformers, A/C units, laadi.ng docks, propane tanks, utility demarcation point on buildings, or other areas potentially visually offensive. existing landscaping to·n:main show existing trees to be barricaded and barricade plan. Protected points will only be awan:led if barricades arc up before the first development permit is issued. ef 13. a ~galffii\:sysrem:'(Jlan'; (or provide note on how irrigation system requirement will be met prior to a::· ~.(2.-{((A"rt\'N fl~ issuance of C.0.) All plans must include irrigation systems for landscaping. Irrigation meters arc separate from the regular water systems for buildings and will be sized by city according to irrigation demands submitted by applicant and must include backf.ow prevention protection.. l{jfl. ~ 14. . '/4 ~ 15. ''I-. •I ~ 16. 17. I. I Gr'• 18. 19. if 20. NOTE: Is there any landscaping in TxDOT R.0.W. ? Yes 0 No ~a'· If yes, then TxDOTpcrmit must be submitted . Will there be any utilities in TxDOT RO.W. ? Yes 0 No 'ts(. If yes, then TxDOTpermit must be submitted. Will there be access fr001 a TxDOT R.O.W. ? Yes CJ No v If yes, then TxDOT permit must be submitted. The total number of multi-fuinily buildings and units to be constructed on the proposed project site. The density of dwelling units per a.ere of the proposed project Provide a water and sanitary sewer legend to include water demands (minimum, maximum and average demands in gallons per minute) and sewer loadings (max.imum demands in gallons per day). Are there impact fees associated with this development? Yes CJ No V Signs arc to be permitted separately. c s c Engineering & Environmental Consultants. Inc. July 27, 200 I Mr. Spencer Thompson City of Coll ege Stati on Development Services 1 I 01 Texas Avenue Co llege Station, TX 77840 Re: Response to City of Coll ege Stati on Engineering Rev iew Comm ents No. 1 Regarding the Drai nage Report fo r the Proposed Privett Dental Development ( 1-50001 44) College Stati on (Brazos Coun ty), Texas Dear Mr. Thompson: CSC Engineering & Environmenta l Consultants, Inc. (CSC), on behalf of ArchiTex (Dallas, Texas) has prepared a response to the City of Coll ege Stati on's review comments dated Jun e 27, 200 I. The City of Co llege Station's com ments are presented in italics, imm ediately fo llowed by a res ponse that addresses the comment. • The Drainage Report for the Development Permit is being reviewed at this time. The engineer will be required to shmv calculations in order to utilize the storm sewer junction box. If you are not permilled to use the j unction box, please plan on re-grading the site in order to drain runoff in another manner. Info rmation presented in the CSC re po11 enti tl ed "Dra inage R~port for Pri vett Dental Development, College Station, Texas, January 3, 200 l" indicates that existin g fl ow to th e refe renced juncti on box during the 10-year storm event is approximately 10 .5 cfs. The pro posed developm ent will result in an incrementa l increase of 5. 7 cfs to the juncti on box fro m th e future parking area fo r the referenced storm event. As a re su It. the total fl ow to the juncti on box wi II be on the order of 16.2 cfs (see attached ca lcu lations). The capacity of the 24-inch storm drain at thi s location is approximately 26 .7 cfs. Therefore, it is our opinion that the proposed incremental flow increase fro m th e developm ent can be accommodated by the ex isting 24-inch storm drain. Please contact either of the undersigned individu als at 77 8-28 10 if yo u have any questi ons or need additional informat ion co ncern ing this matter. Respectfu lly, !/;;, R. ~ A~,~~''' ,.,~ ... -~ .. W.R. Cullen, P.E. J'" ,.• ··,~ ·~ Sen ior Engineer £• / \'"or ~ ..... iLi,W.9i. ·m:· .. -~ .. , ............ ~·:····~ WRC:mf ''°' ·~' Enc losure f1l\ ~ 65215 ~~ /~J via us Mai l ··~~i~~c\~ ~ "'u..~ 7 / J..7 / O I 3407 Tabor Road Bryan, Texas 77808 'fh.'3~~~ M. Frederick Co nlin, P.E. Seni or Engineer Phone (979) 778-2810 Fax (979) 778-0820 • c s c Ir I\ I '!.. L ' t Engineering & Environmental Consultants. Inc. ~ I i-1 .... !/\. • • l ~ ( I < ' ' I 'I. 1 J ~ ' '-' :> ('. /, l , "'! I /fl I r ' 1-. f " vi> IJ -I<.~ I " ' D II. f \ ,) fl I~ - -I 1'11 14. L I /ft ' ' r ~ ,_ I -I 't ·'1 ... \ " ! \ .J. -!'t J ~ 11\ h - ) -..!~ ~ r'\11\ ~ - ) ... I Project: 'T'R.1 VE TT Dz N TA L Created By: W R.. (, < 7 \".('I 4 -I\ t I --.... "' - ( I • 1-... ,, J -I I / I (_ I " '\ ~ \ ,.. --" ~ -'-' ' ~ ':> u J 1.l 1 ,/ ':' Ill v 11 rAT - -I\ ... I I I" ~ I J " I 7 1,,. ~ I In ..L J I J l ' --). ........ ..-le ,_ -... ,, ..... • 1u1c-IC fl -t 1..: . >_ '1 ... 1 } " -_,.A I IA I , \ --\ l I 7 n -· ... ' -_) I 1 ; ~ <. I A rr-\ (" -.. T >• ,, e ··' -; -/. ~,T - ~ f ~ ... l ,,, II"\ I ~ I f ll IC.,'- I/ \· c ~ l I\ ~ -, ;.. " "l 'I I I I ,,. /"I ,_ --. --I/ ---' - "' I 10. I I ) -:. ,, - T I /1~ \ ,., .. ' 1' ' \"1 (..) J 7 I I :: I ----' I '--1 ,, r 'i -1 ~ I --> 1 U<. T "' 7 ...... J v• _, :.+ - -'"\ ... ~ ,, ( " -,_ -~ -~ Date: _1-'--1--!-/;_;:co-1-/_o__,_/_ I I Page_/_ of_/_ - " =, h "}~ I 11 H !f \ -~ --- ' ') ' ', .. , ... ( -, ~ ' \ :r. l l ·- ' --- ~ .., ) -I .t / --; .... .. ~ l ~ -" .. c..; ·~ . ... ,jl •• . •. ,. ' ~ JI ..., .. -.... ~, " .. ,,, ., .. ... ... ·~ ... ·-• • ..i . ·~ .. It I :11 I II-~ I.I~ I. .. . . , .. " . . ... ... . ... ~ 0 II:!• .,. ' . jj,. .... ,. ~ . <.,,11 .... . . . ~ II ·-.. -. "' -.. n u" , -I!' ..... -J. ( I I to..""""""" - I 7 1 '· ({~ DEVELOPMENT PERMIT PERMIT NO. 01-044 Project: Privett Dental COLLlGl STATION FOR AREAS OUTSIDE THE SPECIAL FLOOD HAZARD AREA RE: CHAPTER 13 OF THE COLLEGE STATION CITY CODE SITE LEGAL DESCRIPTION: Lot 1, Block 2 Southwood Forest #5 DATE OF ISSUE: November 19, 2001 OWNER: Privett, William and Sharon 908 Gail Place CS, TX 77845 SITE ADDRESS: 1111 Rock Prairie Road DRAINAGE BASIN: Bee Creek Trib. "A" VALID FOR 12 MONTHS CONTRACTOR: TYPE OF DEVELOPMENT: Full Development Permit SPECIAL CONDITIONS: All construction must be in compliance with the approved construction plans All trees must be barricaded, as shown on plans, prior to any construction. Any trees not barricaded will not count towards landscaping points. Barricades must be 1' per caliper inch of the tree diameter. The Contractor shall take all necessary precautions to prevent silt and debris from leaving the immediate construction site in accordance with the approved erosion control plan as well as the City of College Station Drainage Policy and Design Criteria. If it is determined the prescribed erosion control measures are ineffective to retain all sediment onsite, it is the contractors responsibility to implement measures that will meet City, State and Federal requirements. The Owner and/or Contractor shall assure that all disturbed areas are sodden and establishment of vegetation occurs prior to removal of any silt fencing or hay bales used for temporary erosion control. The Owner and/or Contractor shall also insure that any disturbed vegetation be returned to its original condition, placement and state. The Owner and/or Contractor shall be responsible for any damage to adjacent properties, city streets or infrastructure due to heavy machinery and/or equipment as well as erosion, siltation or sedimentation resulting from the permitted work. Any trees required to be protected by ordinance or as part of the landscape plan must be completely fenced before any operations of this permit can begin. In accordance with Chapter 13 of the Code of Ordinances of the City of College Station, measures shall be taken to insure that debris from construction, erosion , and sedimentation shall not be deposited in city streets, or existing drainage facilities. I hereby grant this permit for development of an area outside the special flood hazard area. All development shall be in accordance with the plans and specifications submitted to and approved by the City Engineer in the development permit application for the above named project and all of the codes and ordinances of the City of College Station that apply. • I Owner/ AgenUContractor Date c s c Engineering & Environmental Consultants. Inc. January 3, 2001 Mr. Spencer Thompson City of College Station Development Services 1101 Texas Avenue College Station, TX 77840 Re: Drainage Report for Proposed Privett Dental Development -College Station, Texas Dear Mr. Thompson: CSC Engineering & Environmental Consultants, Inc. (CSC) is pleased to submit the enclosed drainage reports (four copies) for the proposed Privett Dental Development. The proposed "phased" development will be constructed at a site located on the northwestern comer of the intersection of Rio Grande Boulevard and Rock Prairie Road in College Station, Texas. The owner anticipates that the development will eventually consist of approximately three separate structures over the approximately 1.94-acre site. However, at the present time only one building will be designed and constructed as part of the initial phase of the project. These reports are being submitted for review by the City of College Station in accordance with the provisions of the City of College Station Drainage Policy and Design Standards Manual. Please contact either of the undersigned individuals at 778-2810 if you have any questions or need additional information concerning this matter. Respectfully, 1J;,R.~ W.R. Cullen, P.E. Project Manager tft.Ol~~~· M. Frederick Conlin, P.E. Senior Engineer WRC:mf Via Hand Delivery cc: Basil Privett 3407 Tabor Road Bryan, Texas 77808 Phone(979)778-2810 Fax (979) 778-0820 STAFF REVIEW COMMENTS NO. 1 Project: DP-PRIVETTE DENTAL-DEVELOPMENT PERMIT (1-100044) ENGINEERING 1 . Please contact me concerning the drainage report. 2. As noted in the Site Plan review, a water line will need a plan and profile on construction documents. Sealed and signed engineer's estimates on all infrastructure are also required. Reviewed by: Spencer Thompson Date: June 27, 2001 NOTE: Any changes made to the plans, that have not been requested by the City of College Station, must be explained in your next transmittal letter and "bubbled" on your plans. Any additional changes on these plans that have not been pointed out to the City, will constitute a completely new review. Staff Review Comments J:\PZTEXT\SR1 .DOC Page 2 of 3 08/31/2001 15:51 409-778-0820 • 1111 l'I •' I 'i' (-·- I q ~ ~I I . c J I 8 ~ c CSC ENG & ENV (---··-··-··-··-··-··-~ --··__,,,,,.. ___ .... --·---_ __....-.__.-• PAGE 02 ENGINEER•s COST ESTIMATE FOR THE INSTALLATION OF FIRE LINE ASSOCIATED WITH PRIVETT DENTAL DEVELOPMENT (College Statio~. Texas) Item No. Description Estimated Quantity Unit Price Estimated Cost ~-""'="-r .&'-friR#mH'0cuH'ui~5.·?''.Y-AA~·WNB ;;.a.+;£;;~~~-"'"'~~+-to.~~,u,~:c:i;,§.-:_"~t:..~.~;'~a··-·e-j'.,· .. ·~-~: .. ,~-~~~~~J::~~~;;~'.~~~~-·:- 6" Water DIP (AWWA C150), CL S2 w/0 mii .pcly "wrap:· . . 1 io LF . •--$30.004'·--· -. $5;fo0.00 2 3 4 Excavate and backfill {structural) Tap and Saddle (16"x 6") at Connection Gate Valve Assembly (6-inch) Fire Hydrant and Valve Box Assembly 1 1 1 Page No. 1 of 1 EA EA EA $4,800.00 $4,600.00 $550.00 $550.00 $2,400.00 . $2,400.00 Subtotal: ====·-=$1=2=~8l-=5o=·=oo= Engineering and Survey@ 15% Contingency @ 5% TOTAL · ·----sf,m:SO --·· . --. ---~2~·50 S15,.t20.00 1~ CS> I lf --...J ! --...J I [I') ! I : CS> [I') I\) . CS> 0 (fl 0 [Tl z Gl Qo [Tl z < '1J D Gl [Tl ENGINEER•s COST ESTIMATE FOR THE INSTALLATION OF FIRE LINE ASSOCIATED WITH PRIVETT DENTAL DEVELOPMENT (College Statio", Texas) Item No. Description Estimated Quantity Unit Price Estimated Cost :*£~.:...:.ze=-::.:z(?: __ ._ ---i·_·_-__ , _0_c._.-_.,_ -_-_ .. __ ._-"_-_-_--_-__ .~--'_:_"_r_·_----:~-lilNE_--re ~it(~-~~ -i:_;:-:-=:t.r:-~ *· ._ .. :::_·.·_ ..-===.-• --_ •• -::r.;,.f5 -; _-_--=~~~~-:-~;J.~~t_· :...::~~:::i-.·-· ... ,.#,.~~:-~ ---~---~, -.;-:::7:-~~~-_.:~~~~~)~\:_~~ -• --<..~;;:: -~""'o:==t"' =~ ~ --~.....:C--=3f~-·:::.:·:..~---::~~::.:.i:.b_~~~~~~.;.;~:..:.~·~--- 6" Water DIP (AWWA C150), CL S2 w/0 m ii "p(;iy ~ap:-170 LF . $30.oo" -$5,100.00 Excavate and backfill (structural) 2 Tap and Saddle (18"x 6") at Connection 3 Gale Valve Assembly (6-inch) 4 Fire Hydrant and Valve Box Assembly 1 1 1 Page No. 1 of 1 EA EA EA $4,600.00 $4,600.00 $550.00 $550.00 $2,400.00 . $2,400.00 Subtotal: ====--=$=12=;uo=·=·=oo= Engineering and Survey@ 15% $1,927.50 Contingency @ s% ==·-·=· ·=· ==· --~-"'=--===2===-.-so~· . --.. . . ------··----- TOTAL S15,1t20.00 I I-' I ~ 1~ I _p. . ~ ' l1l I I • -.._J i ~ I I :~ co l'0 -~ () (./) () fTl z G> Qo fTl z < lJ ];> G> fTl sp,.; A .•. •·,, . t . . '• I W.R. Cullen, P.E. Project Engineer REVI W OR co~~ LIAN.C~ AUG 3 O 200,~ .. COLLEGE STATION ENGINEERING DRAINAGE REPORT FOR PRIVETT DENTAL DEVELOPMENT COLLEGE STATION, TEXAS Prepared for City of College Station P.O. Box 1000 College Station, Texas 77805 Prepared by CSC Engineering & Environmental Consultants, Inc. 3407 Tabor Road College Station, Texas 77808 January 3, 2001 csc Drainage Report for Proposed Privett Dental Development TABLE OF CONTENTS Page GENERAL DESCRIPTION OF SITE AND PROPOSED DEVELOPMENT ...................................... . PRE-DEVELOPMENT DRAINAGE PATTERNS AND MAJOR DRAINAGE BASINS.................... 2 SCOPE OF REPORT AND DRAINAGE DESIGN CRITERIA............................................................. 2 STORMW ATER RUNOFF COMPUTATIONS..................................................................................... 3 USE OF THE RA TI ON AL FORMULA........................................................................................ 3 RUNOFF COEFFICIENTS (C) ..................................................................................................... 3 TIME OF CONCENTRATION (Tc}.............................................................................................. 5 RAINFALL INTENSITY (1).......................................................................................................... 5 AREA OF SITE (A)....................................................................................................................... 6 STORMWATER RUNOFF QUANTITIES................................................................................... 6 STORMW ATER DETENTION COMPUTATIONS .............................................................................. 7 REQUIRED MINIMUM DETENTION STORAGE VOLUME................................................... 7 DETENTION STORAGE AREA.................................................................................................. 7 STORMW ATER ROUTING COMPUTATIONS................................................................................... 8 METHODOLOGY......................................................................................................................... 8 ROUTING COMPUTATIONS AND CONCLUSIONS................................................................ 8 CERTIFICATION ............................................................................................................ :....................... 9 REFERENCES ......................................................................................................................................... 10 Table I. Table 2. Table 3. Figure 1. Figure 2. Figure 3. Figure 4. Figure 5. Figure 6. Figure 7. Figure 8. LIST OF TABLES Summary of Runoff Coefficient ("C") Values for Post-Development Conditions............... 4 Computed Rainfall Intensity Values for Referenced Storm Return Period.......................... 6 Calculation of Pre-and Post-Development Stormwater Runoff Rates Using the Rational Fonnula .................................................................................................................. 6 LIST OF FIGURES General Topography in Region of Privett Dental Development Existing Topography and Proposed Site Development Bee Creek Drainage Basin Pre-and Post-Development Hydrographs for 25-Year Storm Event Austin Colony Site Plan Cumulative Outflow (Discharge) versus Depth of Storage Inflow and Outflow Hydrographs Illustrating Routing for 25-Year Storm Event Inflow and Outflow Hydrographs Illustrating Routing for 100-Year Storm Event II csc Drainage Report for Proposed Privett Dental Development GENERAL DESCRIPTION OF SITE AND PROPOSED DEVELOPMENT The site, which is the subject of this drainage report, is located at the northwestern comer of the intersection of Rio Grande Boulevard and Rock Prairie Road in College Station, Texas. The subject property, depicted in Figure I, is situated on a 1.94-acre tract of contiguous property that can be described as undeveloped commercial property. Existing surface vegetative cover at the site consists of isolated native trees and grasses. The surface topography across the site generally slopes toward the east. Adjacent properties can be described as fully developed with residential land usage to the north and east, and recreational land use to the south. The adjoining property to the west supports an assisted living (retirement) facility with an adjacent church and associated parking. It is our understanding that a new dental clinic known as the Privett Dental Clinic is planned for development at the referenced location. We anticipate that the development will eventually consist of approximately three separate structures over the approximately 1.94-acre site. However, at the present time only one building will be designed and constructed as part of the initial phase of the project. The presently planned building will essentially be a single-story structure, although a raised central portion of the building that will be approximately two stories in height may also be constructed. The building will have plan or "footprint" dimensions of approximately 49 by 80 ft or approximately 3,920 ft2 of area. Support paving, either reinforced concrete or hot-mix asphaltic concrete (HMAC) will be installed to the west of the Privett Dental Clinic building and will include an entry drive onto Rock Prairie Road. Although the Privett Dental Clinic will be the only structure constructed during the initial phase of the development, the owner had expressed interest in the design of applicable detention facility for fully developed conditions. The following structures and respective covered areas (roof or slab, whichever is larger) are planned for the proposed development (fully developed): • Structures -dental office (3 ,765 ft2) and two future office buildings (4,025 ft2, each) • Pavement and sidewalks -dental office sidewalk (1, 113 W), dental office pavement (8,915 ft2), future office building pavement (18,926 ft2). The total impervious cover associated with the proposed development is approximately 40,770 ft2 (.93 acres). It should be noted that the grass cover and associated slopes for greenspace and landscaped areas proposed to be developed on the site are similar in character and grade to the existing "pre- development" conditions. As a result, these landscaped areas were not considered as adding to the quantity or rate of stormwater runoff associated with post-development conditions. csc Drainage Report for Proposed Privett Dental Development PRE-DEVELOPMENT DRAINAGE PATTERNS AND MAJOR DRAINAGE BASINS The 1.94-acre site is located in the Bee Creek subbasin of the Carter Creek Drainage basin as illustrated on Figure 2. Topographically, the surface elevation decreases by approximately 3 ft for a distance of 420 ft across the site, from El 317 msl near the northwest comer to El 314 msl on the southeast comer of the property. This easterly drainage pattern is consistent with a slope of approximately 0.7%. There are no distinct drainage channels across the site. Stormwater runoff from the site is predominantly by sheet flow to Tributary "A" of Bee Creek. The 100-year floodplain is not present within the site boundaries. SCOPE OF REPORT AND DRAINAGE DESIGN CRITERIA This report addresses the need for detention of drainage from the subject site following the construction of the planned Privett Dental Development. The site and proposed development were evaluated in accordance with the criteria outlined in the Drainage Policy and Design Standards Manual (DPDSM) of the City of College Station, Texas. The DPDSM is part of the Stormwater Management Plan for the City of College Station. It should be noted that detention requirements for the planned development were evaluated based on runoff characteristics for the larger drainage subbasin in which the subject site is located. This approach was deemed appropriate due to the current drainage patterns in the area of the subject site as depicted on Figure 2. As can be seen from a review of Figure 2, there is an existing drainage feature that currently crosses a portion of the proposed project site. The drainage feature consists of an existing curb inlet, a reinforced concrete pipe (RCP) outlet from the curb inlet, and an open ditch along Rio Grande Boulevard into which the RCP outlet pipe flows. The curb inlet is situated on the northern side of Rock Prairie Road adjacent to the site and services the northern portion of Rock Prairie Road to approximately Westchester Avenue to the west and a strip of developed land adjacent to the northern side of Rock Prairie Road. The RCP is 24 inches in diameter and flows northeastward from the curb inlet box before making a 90° turn to the northwest to discharge into the open ditch along Rio Grande Boulevard. The open ditch is grass lined along the boundary of the subject site but becomes concrete lined to the north of the site. The flow in the ditch is to the northwest and Tributary "A" of Bee Creek. As a result, the "site area" for the analysis discussed herein was considered to be the entire contributory drainage based on the previously described drainage feature that traverses the site. The contributory drainage consists of both off-site and on-site areas that total approximately 5.93 acres. This 2 csc Drainage Report for Proposed Privett Dental Development report also discusses specific drainage control structures related to the detention of stormwater runoff from the proposed development. STORMWATERRUNOFFCOMPUTATIONS USE OF THE RATIONAL FORMULA The Rational Formula was used to compute the total volume of stormwater runoff generated from the fully developed site and to assess the quantity of stormwater which was required to be detained to "offset" the increased runoff associated with the new 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 stormwater 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 values for each of these components used to compute the stormwater runoff at the subject site are discussed in the following sections. RUNOFF COEFFICIENTS (C) The runoff coefficients or "C" values were computed for both pre-and post-development conditions for the entire 5.93-acre drainage basin area. Pre-development conditions were assumed to represent the entire drainage basin area including the 1.94-acre subject site in its present condition, i.e., as an undeveloped grass and tree covered area. The post development conditions were assumed to be the same for the drainage basin with the exception that the 1.94-acre lot was developed by the addition of buildings, paved parking and drive areas, and landscaped areas. The values of the runoff coefficients used 3 csc Drainage Report for Proposed Privett Dental Development for the pre-and post-development conditions were the values presented in Table III-1 of the DPDSM for different types of surface covers and land uses. Pre-Development "C". The coefficient for the pre-development condition for the entire 5.93- acre drainage basin was a constant value based upon existing and proposed land use. A land use description corresponding to "Medium Density Residential (Average Slope 0-1 % )" as presented in the previously referenced Table lll-1 was used in the analysis. The range in C values for the described land use was listed as 0.55 to 0.65 in Table III-I. Therefore, an average C value of .55 was used as being representative of the entire drainage basin for pre-development conditions. Post-Development "C". The post-development "C" values were also determined from the referenced table. Values of runoff coefficients for the areas of the drainage basin outside of the subject site area were determined based upon the land use category described as "Medium Density Residential" in Table III-I as previously described. Values of runoff coefficients representative of post-development conditions for the subject site were based upon specific types of land cover associated with the development. Two types of land cover were used to represent the proposed development. One type of cover was intended to represent the planned buildings and paved areas, which are areas referenced as "Impervious Areas (Pavements, Rooftops, etc.)" in Table III-I and have a recommended C value of 0.90. The second type of cover was assumed to be landscaped areas with finished slopes in the range of 1 to 3.5%. Table III-1 recommends a range in C values of 0.40 to .070 for landscaped areas with comparable slopes. A value of 0.55 was chosen for the analysis since the finished grade slopes will be closer to 1 % than to 3 .5%. An average or weighted C value was then computed for the entire drainage basin, considering the changed surface covers produced by development of the subject site. The calculations for the average or weighted C value are presented in Table 1. Table I. Summary of Runoff Coefficient ("C") Values for Post-Development Conditions Type of Ground Cover Off-site Area, Medium Residential Area On-site Area, Concrete sidewalks, buildings & pavement for Privett site On-site Area, Landscaped Areas Summation 4 Area of Coverage, (square feet) 175,982 40,769 43,560 260,311 Extended Typical "C" Multiplication of "C" Values Values x Area 0.55 96,790 0.90 36,692 0.55 23,958 157,440 csc Drainage Report for Proposed Privett Dental Development Therefore, the average "C" value associated with the post-development conditions can be determined by dividing the overall basin area (260,311 W) into the summation of extended multiplication of the individual areas times the respective "C" values (157 ,4400 ft2): Average "C" value= 157,440 ft2 I 260,311ft2 =0.60 Thus, the weighted "C" value across the site for post-development conditions was determined to be approximately 0.60. TIME OF CONCENTRATION (tc) The time of concentration at a site is used to determine the intensity of the rainfall event used for computing stormwater 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." The time of concentration for the subject site was calculated based upon the elevation difference and the flow distance from near the northwest portion of the subbasin, to the recessed inlet on Rock Prairie Road, to a point of discharge in the existing open ditch on the northeast corner of the subject property as illustrated in Figure 3. The slope or grade of the site for pre-development conditions was determined from the general topographic maps of the City and the topographic survey of the site. The slope for post-development conditions was determined from the proposed site grading plan, which will be consistent with the existing site topography with the exception of localized grading near the proposed structures. Using the surface travel distance of approximately 1 ,600 ft and a weighted flow velocity computed from the various methods of conveyance along the flow path (Figure 3), a time of concentration of 10 minutes was determined for pre-development flow. The post-development time of concentration was computed in a similar manner to using a flow distance of 1,600 ft. The time of concentration for post- development conditions was also computed to be 10 minutes using a weighted flow velocity of 2.7 ft/sec (Figure 3). Based on DPDSM criteria, a minimum time of concentration of 10 minutes is required for the design of drainage system components, including detention facilities. RAINFALL INTENSITY (I) The rainfall intensity values were computed for the 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 I 00 years are indicated in Table 2. 5 csc Drainage Report for Proposed Privett Dental Development Table 2. Computed Rainfall Intensity Values for Referenced Storm Return Period Storm Return Period (years) AREA OF SITE (A) 5 10 25 50 100 Rainfall Intensity (inches/hour) 7.7 8.6 9.9 11.l 12.3 As previously discussed, the site proposed for development encompasses approximately 1.94 acres. However, due to the previously discussed pre-existing drainage conditions, detention requirements were evaluated based on a subbasin area of 5.93 acres. Accordingly, computations associated with the evaluation of stormwater runoff were developed using an area of 5.93 acres. STORMW ATER RUNOFF QUANTITIES Stormwater runoff rates were calculated using the Rational Formula. Runoff rates were calculated for both pre-and post-development conditions for the 5 .93-acre site and are presented in Table 3. Table 3. Calculation of Pre-and Post-Development Stormwater Runoff Rates Using the Rational Formula Storm Site Area0re Site Area00•1 Intensity pre lntensity00•1 Q 1pre Qpost Q 2 difT Event (acres) (acres) Cpre Cpost (in/hr) (in/hr} (cfs) (cfs) (cfs) 5 5.93 5.93 .55 .60 7.7 7.7 25.3 27.8 2.5 JO 5.93 5.93 .55 .60 8.6 8.6 28.4 31.2 2.8 25 5.93 5.93 .55 .60 9.9 9.9 32.4 35.6 3.2 50 5.93 5.93 .55 .60 I 1.1 11.1 36.7 40.3 3.6 JOO 5.93 5.93 .55 .60 12.3 12.3 40.5 44.5 4.0 Notes: I. Permitted rate of outflow from detention basin. 2. Difference in flows that will require detention. The calculated pre-development flows presented in Table 3 for the 25-year storm event represent the maximum permissible discharge flow rates from the detention facility. The difference in the pre-and post development flows for the 25-year storm event listed in Table 3 (Qdiff = 3.2 cfs) represents the increase in flow rate from the development that must be detained. 6 csc Drainage Report for Proposed Privett Dental Development STORMWATER DETENTION COMPUTATIONS REQUIRED MINIMUM DETENTION STORAGE VOLUME The required storage volume of the detention basin was calculated such that the peak discharge of the ultimate development hydrographs for the 25-year design storm was limited to a discharge less than a defined target discharge. The target discharge was defined by the DPDSM to be the peak discharge of the pre-development hydrograph for the 25-year storm event. As previously mentioned, detention requirements have been computed for "fully developed" conditions even though the site development will occur in a phased approach. The required detention storage volume was determined as the difference in area between the pre- and post-development hydrographs, which are depicted on Figure 4. The Triangular Approximation Method was used to determine the hydrographs. The hydrographs were constructed by assuming that the 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. By comparing the two hydrographs in Figure 4, it is apparent that the differenc~ m areas attributable to increased flows from the proposed development is relatively small. As previously discussed, both the pre-and post-development flows were developed for the entire 5.93 acres of contributory drainage area. The difference in area between the two hydrographs, or the required minimum volume of the detention storage area for the 25-year storm event; was calculated to be approximately 2,900 ft3. A 10% increase in the required volume as specified in the DPDSM resulted in a design detention volume of 3, 190 ft3. DETENTION STORAGE AREA Given the relatively low storage volume required for detention and existing site conditions, the owner has elected to take advantage of the natural topographic features and construct a detention area within the existing drainage area at the site. The location of the proposed stormwater detention is presented in Figure 5. The average depth of the drainage basin is approximately 2.0 ft from El 310 to El 312 ms!. The volume available for detention is approximately 3235 ft3, which is approximately 2.0 % 7 csc Drainage Report for Proposed Privett Dental Development larger than the required volume of 3, 190 ft3. An outlet structure will be constructed on the north end of the drainage basin to control discharge from the detention facility. STORMWATERROUTINGCOMPUTATIONS METHODOLOGY The detention basin was analyzed for flow routing through the areas under different storm events. The purpose of the routing analysis was to simulate the performance of the detention basin in the form of inflow and outflow hydrographs. The storage-routing analysis was performed based upon the Puls Method. The Puls Method is a procedure for graphically solving the continuity equation for storage reservoirs using the characteristic height-storage and height-discharge curves. As previously discussed, the equivalent of the height-storage curve was developed graphically from the grading plan and the invert elevation of the outlet structure. A height-discharge or discharge versus depth of storage curve was also developed for the outlet structure. The curve for the area of interest is illustrated in Figure 6 -Cumulative Outflow (Discharge) versus Depth of Storage. ROUTING COMPUTATIONS AND CONCLUSIONS Routing analysis was performed for two storm events: the 25-year event, which represents the design storm; and the 100-year event as specified in the DPDSM. Inflow and outflow hydrographs illustrating routing for 25-year and 100-year storm events are presented graphically on Figures 7 and 8, respectively. As can be seen from Figure 7, the maximum outflow from the detention basin is approximately 14 % of the maximum pre-development rate of 32.4 cfs. Therefore, the detention basin has the capacity to store the excess volume of storm water associated with the planned development of the site and 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 [25-year] storm" as specified in the DPDSM. In addition, the results of the routing analysis for the 100-year event as illustrated in Figure 8 indicate that the higher flows associated with this event will flow over the top of the spillway and not adversely impact the integrity of the basin. 8 csc Drainage Report for Proposed Privett Dental Development CERTIFICATION "I hereby certify that this report for drainage design of the stormwater detention basin at the 1.94-acre Privett Dental Development located at the intersection of Rock Prairie Road and Rio Grande Drive in College Station, Texas, was prepared under my supervision in accordance with the provisions of the City of College Station DPDSM for the owners thereof." W. R. Cullen, P.E. Registered Professional Engineer State of Texas P.E. Number 65215 9 csc Drainage Report for Proposed Privett Dental Development REFERENCES Chow, Ven T., Maidment, David R. and Mays, Larry W. 1988. Applied Hydrology. McGraw-Hill Book Company. New York, NY. City of College Station, Texas. October 1992. Drainage Design Guideline Manual. Davis, Victor D., and Sorensen, Kenneth E. 1969. Handbook of Applied Hydraulics. McGraw-Hill Book Company. New York, NY. Mason, John M. and Rhombrerg, Edward L. 1980. On-Site Detention. Prepared for Texas Engineering Extension Service, Texas A&M University. College Station, TX. Publication No. PWP: 03355-01. McCuen, Richard H. 1982. A Guide to Hydrologic Analysis Using SCS Methods. Prentice-Hall, Inc. Englewood Cliffs, NJ. United States Department of Agriculture. January 1975. Urban Hydrology for Small Watersheds. Technical Release No. 55. Engineering Division, Soils Conservation Service, U.S. Department of Agriculture. Wanielista, Martin P. 1978. Stormwater Management Quantity and Quality. Ann Arbor Science. Ann Arbor, MI. Westaway, C.R. and Loomis, A.W. 1979. Cameron Hydraulic Data. (161h Edition). Ingersoll-Rand. Woodcliff Lake, NJ. 10 FIGURES 35 30 25 i a 20 u.i ~ 15 0 en c 10 5 0 Opost = 35.6 cfs Opre = 32.4 cfs 5 c s c 10 VOLUME OF DETENTION STORAGE (EQUALS DIFFERENCE IN AREA BENEATH EACH HYDROGRAPH) /POST-DEVELOPMENT / HYDROGRAPH PRE -DEVELOPMENT HYDROGRAPH 15 20 TIME, (minutes) 25 30 Engineering & Environmental Consultants, Inc. PRE-AND POST-DEVELOPMENT HYDROGRAPHS FOR 25-YEAR STORM EVENT PROJECT: LOCATION: COLLEGE STATION PRIVETT DENTAL APPR: REV.DATE: DRAWN BY: BWD SCALE: NOT TO SCALE DATE: 12121/00 FIGURE NO.: 4 7.0 8.0 5.0 i a 4.o ui ~ % 3.0 0 UJ 0 2.0 1.0 0 0 0.5 OVERTOPPING OF DETENTION POND 1.0 1.5 2.0 2.5 3.0 3.5 DEPTH OF WATER IN DETENTION POND, (ft) c s c Engineering & Environmental Consultants, Inc. CUMULATIVE OUTFLOW (DISCHARGE) VERSUS DEPTH OF STORAG E r========"J'n--~FOl:;=========]~P~R~OJ====-ECT:=..:-:~~~~~~~~~~~~~~~~---1• LOCATION: COLLEGE STATION PRIVETT DENTAL APPR: REV.DATE: DRAWN BY: BWD SCALE: NOT TO SCALE DATE: 12/21IOO FIGURE NO.: 8 35 30 25 -~ -a 20 u.i ~ 15 (.) en c 10 5 0 5 ~INFLOW OUTFLOW 10 15 20 25 35 TIME, (minutes) c s c Engineering & Environmental Consultants, Inc. INFLOW AND OUTFLOW HYDROGRAPHS ILLUSTRATING ROUTING FOR 25-YEAR STORM EVENT I MWE~: LOCATION: COLLEGE STATION PRIVETT DENTAL APPR: REV.DATE: DRAWN BY: BWD SCALE: NOT TO SCALE FIGURE NO.: 7 DATE: 12121/00 40 35 -~ 30 -a w 25 ~ 20 :::c: 0 "' c 15 10 5 0 0 5 DETENTION POND AT CAPACITY EMERGENCY SPILLOVER OCCURS INFLOW = OUTFLOW OUTFLOW 10 15 20 25 30 35 TIME, (minutes) c s c I Engineering & Environmental Consultants, Inc. PRIVETT DENTAL INFLOW AND OUTFLOW HYDROGRAPHS ILLUSTRATING ROUTING FOR 100-YEAR STORM EVENT PROJECT: LOCATION: COLLEGE STATION APPR: REV.DATE: DRAWN BY: BWD SCALE: NOT TO SCALE DATE: 12121/00 FIGURE NO.: 8