Loading...
HomeMy WebLinkAboutSite Certifications - 05/10/2002Mr. Jay Barber City Of Fort Collins Stormwater Utility Department P.O. Box 580 Fort Collins, Co 80522-0580 Re: Willow Springs Office Building Stormwater Certification Project No. 0819-003 Dear Mr. Barber: February 7, 2002 z Please find enclosed a completed Drainage Certification Form for the Willow Springs Office Building for the as -built condition. TST, Inc. surveyed the above improvements on January 8, 2002, as the contractors constructed them. The office building had a design finished floor elevation of 4945.65 and an as -built of 4945.75. The construction of the parking area, curb cuts and grading has been completed as shown on the approved plans. At the time of the survey, minor grading and landscaping were still required, however the storm drainage facilities, unless noted below, are in place and should function as designed. Please note on the attached drawing that the owner/contractor did not build the concrete pan on the north side of the building. This area was designed to drain into the parking lot and eventually into the detention pond. The area now includes a small area of the roof drainage and landscape area that drains directly to Battiecreek Drive, which then drains east to Timberline Road and eventually to the inlets at McClelland Channel. The area described is 0.0314 acres and generates only 0.22 cfs of runoff. It is our opinion that this additional flow to the undetained off -site basin is minor and will not affect the overall drainage during a 100-year storm event. Also, the owner/contractor did not build the concrete pan from the parking areas down into the detention. They propose to replace the concrete pan with 5'x10' pad of large cobbles (Class 9) at the discharge points of the parking lot to prevent erosion along the bank of the detention pond. The large cobbles will be installed with the landscaping, which should be completed by mid -March. Again, it is our opinion that this is a minor change to the overall drainage during the 100-year event. Please refer to the attached drawing illustrating the as -built elevations of the parking lot and finished floor elevation. Also shown are the areas that changed as detailed above. Please contact me should you have any questions regarding this Drainage Certification. Sincerely, TST, INC. CONSULTING ENGINEERS riene .Ahado"wen, P.E. SAS/ Enclosures cc: Bo, Drahota Construction Byron Collins, Paragon Point Partners TST, INC. 748 Whalers Way - Building D Fort Collins, CO 80525 Consulting Engineers (970) 226-0557 Metro (303) 595-9103 Fax(970) 226-0204 Q Email info@tstinc.com www.tstinccom Willow Springs *(6 bil DRAINAGE CERTIFICATION FORM Please fill out all applicable items in this certification form for single family, multi -family and commercial properties. Write "OK" for items checked or actual number checked in field. Use "N/A" for items that are not applicable to the property that is being certified. A. Drainage facilities certification 1. Pond Certification -volume verification a. topographic records and volume b. cross -sections and spot elevations -positive fall to pan -side slopes -invert elevation -spillway elevation -placement and size of riprap -side slopes -grading -orifice plate installation and size -compaction of berm structural integrity of pond 2. Swales -location (are they within easement) -dimensions and cross-section verification -longitudinal slopes and side slopes -spot elevations NA -permanent erosion control measures Na (drop structures, riprap, etc..:.) -tie-in to pipes, pans, curbs, etc.... -weir size (elevations, size, opening, etc...) -available freeboard -landscaping infringement on swales 3. Pi-oes -size and -type NA -:slopes (as -built and comparison to minimum 0.4% slope) -pipe capacity calculations if slopes are significantly altered -invert elevations -installation and backfill material -cover -encasement and clearance from other utility lines close by -joints 4. Concrete Pan Channels -size NA -slope -super elevation -cross-section -thickness -elevations S� A'ft13t�I�D I6-ffER 5. Inlets -size and type NA -size of opening (or name of standard used) -grate elevation -invert elevation -box size S. Cross vans -sizes OK -type -grade -elevation -cross-sectional depth -tie-in to curb and gutter 7. Culverts -size NA -type -invert elevation -headwalls S. Underdrains -size Iy Qt -type -cover -backfill -geotextiles -cleanouts NA 9. Curb cuts -size -tie in to swale, pipe, etc.... OK B. Certification of Grade Elevations Adjacent to Drainage Facilities: -minimum opening elevations OK -top of foundation elevations OK -comparison to 100 year WSEL's OK (Freeboard requirements and floodplain issues) C. Certification of Erosion Control Measures: 1. Permanent Measures: -Permanent vegetation (6" bare spots and weeds under control ) �QhGQlP�11� II -riprap will W Com�Cil tnhG � -riprap bedding IGn(pinQ./ JJ -drop sections —fj _ o0 -sediment basins/water quality ponds NA_ -netting mats/blankets NA -mulching OA 2. Temnorary Measures: -mulching Na -inlet filter installation -check bale dams -seeding and temporary vegetation -silt fence D. Site Cleanup After Construction -construction clean up V -smoothing of ruts NR -reseeding E. Statement of Compliance This certification is signed and stamped and by signing this form the engineer(s) attests that to the best=of his knowledge the as' -built conditions of the drainage facilities are'as'" described in the above form and in the;redlined.plans:enclosedj Gtrnd +H G q:*OtGhui Itite r. Failure to properly disclose.all known information could result in the rejection of this certification and prevent the release of any Stormwater Utility holds on Building Permits and/or Certificates of.Occupancy. Fa Signature and S Engineer. Istered Professional TST, INC. Consulting Engineers CLIENT - I /� �(/�1/7JOB NO. �I I q �lDD��(/'j PROJECT WIj[0W /Vr Lh Q7 1/111 C-L CALCULATIONSFOR 1/1 M/YI L(.U1G/ �1I 1w"I1 MADE BY DATE CHECKED BY_ DATE SHEET OF 1. �,,und�f-•wn d -t iMhes- - you �1!tnmlac ( jn -- �a►1C�C�pin9 - - --- - - = (oZ4-s� - c_- a Lo__._ - -- -- - - T -- I 3 11269 r - - r L -.`r 16I - .' �r - - r �Y I I I- 1 � I� - I _w-- I ' 1 I l i I I� i t � ��I I ��- I�T � I I I I I +-1---•-. - _- DFF. ,-,c 2�- L)�.Cr K:\819\003\survey\field\draincert.asc 12003, 12047.789321, 9702.699974, 4942.449655,FL PC 12004, 12045.031208, 9693.199815, 4942.588123,FL 12005, 12037.997573, 9685.291932, 4942.960354,FL 12006, 12023.749867, 9684.800341, 4943.328686,FL PT 12007, 12004.449163, 9691.073586, 4943.664705,FL PC 12008, 12000.137307, 9693.921554, 4943.558706,FL 12009, 12001.161098, 9700.192387, 4943.482857,FL 12010, 12004.007920, 9708.952968, 4943.308002,FL 12011, 11936.511742, 9731.048499, 4942.654794,END FL 12012, 11934.987404,, 9732.152955, 4942.644214,BEG FL 12013, 11930.201652, 9718.171628, 4943.027286,FL PC 12014, 11928.697297, 9716.287348, 4943.089505,FL 12015, 11926.634604, 9716.360656, 4943.070504,FL PC 12016, 11922.488211, 9717.946844, 4943.131133,FL PC 12017, 11920.931921, 9719.356177, 4943.128015,FL 12018, 11920.773706, 9721.290995, 4943.156623,FL PC 12019, 11925.073723, 9734.724345, 4942.918673,FL 12020, 11858.539517, 9756.559189, 4941.840660,END FL 12021, 11856.788976, 9757.543479, 4941.824912,BEG FL 12022, 11850.983075, 9739.398140, 4942.354169,FL 12023, 11849.306337, 9736.827157, 4942.323117,FL 12024, 11840.545984, 9732.602969, 4942.140587,FL 12025, 11837.657326, 9732.340816, 4942.123317,FL 12026, 11822.192357, 9737.231653, 4941.649858,END FL 12027, 11822.157266, 9735.196599, 4941.683360,BEG FL 12028, 11803.353710, 9677.316884, 4942.062428,FL 12029, 11817.157447, 9672.800523, 4942.715495,FL PC 12030, 11818.947865, 9671.461144, 4942.777689,FL 12031, 11818.665008, 9669.839687, 4942.831398,FL PC 12032, 11814.995775, 9665.069639, 4942.896263,FL 12033, 11809.806450, 9661.395264, 4942.971048,END FL 12034, 11801.333559, 9657.894229, 4943.113422,BEG FL 12035, 11782.724686, 9646.555437, 4943.845045,FL 12036, 11772.454201, 9632.294617, 4944.843930,FL PC 12037, 11764.778966, 9625.075018, 4945.222547,FL PC 12038, 11747.228735, 9627.617686, 4945.649174,FL 12039, 11808.536378, 9601.350775, 4944.887216,FL PC 12040, 11795.672342, 9609.947966, 4944.942306,FL 12041, 11793.416854, 9621.916847, 4944.829930,FL PC 12042, 11796.234888, 9626.492351, 4944.357109,FL 12043, 11799.821306, 9629.973236, 4944.037966,FL 12044, 11810.261820, 9635.828150, 4943.640929,FL 12045, 11813.033252, 9635.779589, 4943.681937,FL 12046, 11815.320820, 9633.740272, 4943.764690,FL PC 12047, 11819.634967, 9620.917610, 4944.041913,FL PC 12048, 11834.777058, 9627.613917, 4943.942805,FL 12049, 11839.808841, 9630.592970, 4943.947940,END FL 12050, 11848.643589, 9638.276923, 4943.960586,BEG FL 12051, 11852.136992, 9642.991513, 4943.975638,FL . 12052, 11855.588933, 9649.519874, 4943.923710,FL 12053, 11844.631795, 9654.727066, 4943.782263,FL PC 12054, 11841.884307, 9657.735828, 4943.717837,FL 12055, 11842.302614, 9663.008449, 4943.676258,FL PC K.c. 12056, 11853.860257, 9698.811968, 4943.327967,FL PC 12057, 11861.829050, 9707.996212, 4943.528137,FL 12058, 11873.404575, 9708.670454, 4943.568322,FL PC 12059, 11874.928836, 9708.032879, 4943.624358,END FL 12060, 11880.822088, 9706.153547, 4943.847748,BEG FL 12061, 11882.287236, 9705.661145, 4943.944127,FL PC 12062, 11885.294089, 9703.946467, 4944.019605,FL 12063, 11885.583066, 9700.226014, 4944.094982,FL PC 12064, 11881.686131, 9688.235529, 4944.292098,FL 12065, 11922.975436, 9674.564469, 4944.484897,END FL 12066, 11928.549856, 9672.755383, 4944.384585,BEG FL 12067, 11935.469438, 9670.400576, 4944.277545,FL 12068, 11939.594665, 9681.720548, 4943.908347,FL PC 12069, 11942.067924, 9684.706945, 4943.799592,FL 12070, 11946.458039, 9684.638459, 4943.778523,FL PC 12071, 11947.932433, 9684.279847, 4943.770194,END FL 12072, 11954.337972, 9682.299329, 4943.793915,BEG FL 12073, 11955.188757, 9681.814127, 4943.835415,FL PC 12074, 11958.508621,' 9679.505772, 4943.944531,FL 12075, 11958.295327, 9674.808768, 4944.173475,FL PC 12076, 11955.072375, 9664.155071, 4944.735926,FL 12077, 11997.545966, 9650.225659, 4944.728614,FL 12078, 12001.217870, 9661.338433, 4944.410388,FL PC 12079, 12003.537819, 9664.596129, 4944.326259,FL 12080, 12007.481338, 9664.559959, 4944.284881,FL PC 12081, 12016.341780, 9661.919010, 4944.041051,END FL 12082, 12023.465273, 9659.659139, 4943.834959,BEG FL 12083, 12028.662353, 9655.577345, 4943.588666,FL 12084, 12032.927213, 9642.057538, 4943.278975,FL PC 12085, 11969.966865, 9645.993454, 4945.754511,FFE r.a,E�rTks se.oea.��,e.�ue�w roseoxmwcSTAowurw.e sma� radio ewurtoeY.w wtE. hnn.IM w�et Ow. tIONT OEM of MONSWIMM Ofte tvOK ASP /A f e. EgVfV MV S1 Or If (ISO on Off as OS2 A too rvAv *n w. 04 n naonnpSL e-IlrR 9LYa1(N pNfL(.'( S CC�K~ to alYG `;I to �- AhGnK. OP. r ); Lu U " ),ENflp a m r'„ w F"f4q pas 6 RbP �>.S'r f0' ✓W %f f f JCdCVC.F aAv V J. 61� A � PN Au F. —4 BU/LO/YC F. egwT*c'fs 4}15.T5 low &4Gv5 n -Ioft/ i 052 `I 5 W� PN Ae PY4^ O,1- 4 A f7Zoom— I - i f I OP _-c_ WHITE WILL WO DRIVE 110 l n - Vi to lit of to i to It of If i I, GirFP Murs,, Ox of Or �r AOREXPAN 0 �P,1µPr ci0 N�p9 �.. I'cVW WE II LN,';• ' CWCAFz RAN OP IA PtI np.0 4301 f .^ I all PI)Ac o v 9wb 1•�% Il PwL �101 to \ \\ Cdble rlprA�. .A 1\ w-igall \ %vkle� �a1RB car a he (Ton) AWN,.", \ J' LMYeFIP PAN (FACT B .•WK%FIF PAN v J.aal WI 0E7EN77ON POND MO m N G✓ on. >.Y5 Ac-4.. ACl/K GPAPPY- /N At,-4 IP>r as a. AEURN f. -lwaaW cLwH ILVr NIM - Me an e' WIAe )(pot An[AY ll eh FMIDg4W � G> R. AMOK rounte pelt WrRR a A$9Y lI ewsleucr No ciAn anhot a AvrW T A5 9mxN 4&44 MR. aT Nv un 1 ______________________-________ City of Pt. Collins, Colorado UTILITY PLAN APPROVALQy/,, PoolPool/, PP.ow mW,..fw P.1. g1ECxE0 BY: Ba If �-s Psl. >ECBED BY: �.L >trmwler uvy DW WEMD BY: Prtb a PsuWlm Pit. WECxm BY PP. ataEo Or. m LEGEND w7 xis-eaw kzy AREA( (N .SI.B-BLSM WE IXS/GV ANr 5XV MACY y ass AxPo,r 601Ya MIEW ,ng y y, SME, MLE BWMLR a66.10 PRWJYD aFM1wr4W NOTE&FM1MSWD aaaw C(EVAr SIEVE BC A AMMMUM AS Shmel Shot nor UAPP/B P4N S. MYEr of ICRS SNP FF , A' Sr SEERAE 5 S j BE AWN)AM9 so' n( DfWZOMYI AT AIMUUR NaRMS PO CNSUFC P ART hbr Af2BT0. > , Al" ao RTMVN 1N PEACE UNIN Mt RT✓RZAI ASS CSPABLSNCO 17MT F ON A45 MM LANOSLIPCD. S A([ SPOWI MUR FA011W ARC m M 4140'r"a By PROPERTY met IWSl0N Mllr ( AtlTCb 1. The City of Fort CONhs bformroto UNity erosion control inspxror must he narifrod Or /east 24 hours pear to any canslackan on the Site 2 Al/ fep✓irod perimeter sift ISAMIng shot/ be bstuned pn'or to any sort diefurbiog ocriviy (stxkppng, sldppa , gatebg, etc) Alf other fequbvY erosion central meosures Shelf be jaeloate at the appro an ISE time in the construction sSQYence as Indicated in he OpprOMC pra/ect Mheduh, construction plans OnG, erosion control wood J Pro -disturbance veyerof/on shell be profxfed one attuned whenever passlae. Removal. Of disrurbame of VAishng vegefofion Shan be Fnmihe to rhr area AQYired / immediate cWshKtbn Opllafidls, Ond /W the shortest partkat pen'od of time. s. An ease erpoeee dung .halt A)rurbbg ecri,+ry (f poing, g(Oeing, ufik'ty iastonabOr,, elackpi6V, E2rq, ere.) Allolf be kept / a roughened condition by rWng Or ehcing obng land caMOSOT until mach, vegNE't on, or Other permanent erasion contra/ is Anslahee fro soh in ovens Outside 0OMPArct street rights of ray shall rsmmn a Dose✓ by bad C'sfOahV Oc6vdy fa move than thirty (M) days before afeaved hnobot or permanent ero5ran coma (e.g. seed/ inch, bnesceping, etc.) is ,Mslonee, anhee orherwhe ogaro.wd by the Slormrorer Malzol. 5. The propo(y shall be watered and mamtoinel at ON times airing constuction actlobas so as to prevent woad-coueee erosion. AR land ShOurovV averwMes shot/ be havroa ofey C}cantinuee when 41NIAR dust yEpOche adjacent proprrth5 as determined by the City of Fort Col/ins Eglneerirg bbpaldnoto 6. AM tefnaarory (srruclurv/) eroson central meosuns shall be inipecfM One aeonon rrconslrvcfed as necessary after each runaff event IN order to flnuee prl moxe or Mein infeMM function. As relolnM safimMrs, (M16Coof MOM M p0✓ed rWe y surfaces. 400// be larnOMd Ord asposee of in o morvrx orM location M as to court their release into ory n llageway z No sod srockph s/rolf e:ceee ten (10) feet m height AR sml sMckahs shall be pro(ecred from soloolato tronsporr be sun a roughenlrV. woMing, R ! m M sal sbc rb mmaim fs JO do shun oM meters lop rq ye per; 9 y be seeded orM mulched R. Ci/y Ordmonce probWBs the tracking, dropping p ✓eposiling of soils of any other motena/ onto CT, streets by o 1 any veMcb. My everoaent deposited morerie/ shelf be throve immed'orey by the contactor. 9 Instal/ grow/ kiet Men, On 0# MMS 10. 5,11 fence shelf be Mnf, 7nvirofence ICOy' or oplaraved equal. II. straw bah bamers we to be Nvb/hd Immadarey fo/bw hg the goading 12 Al/ areas drsfudIef by conslrvetmn she/be rood to Occaadmg Po the AcAnsrope plan thoseITthose, o dNay in hurting ronsfrucfan, the pod is 10 be rele5em one rrwkhee IS rho denott o she// be responsibh far mamfommy elf Sort contra forilrhes, inching neMeRM areas. Sono a hearty state of vegetarian Ives ban esroaished. V z _1 LL F X fee U z EE d V! U J J i z n z0 0 J_ z D W O U LLI Z UU 00 v% Ir IL Z 06 ^ li LL Q 0 z a cc c V e 1 3