Loading...
Drainage Report• ADT Self Storage Drainage Report 7103 Rock Prairie Road College Station, Texas October 2008 Prepared for: ADT Self Storage 5630 S. Waterbury Way Suite B-100 Murray, Utah 84121 Prepared by: Kimley-Horn and Associates , Inc. 11 1 University Drive East Su ite 105 College Station , Texas 77840 11111"'1-llrll Kimley-Horn llllli.....J-[__J and Associates, Inc. Executive Summary Report Contact Infornrntion Developer DCB Construction 909 E. 6211d A venue Denver, Colorado 802 16 (303) 287-5525 Contact: M ark Delgado Identification Engineer K imley-Horn and Associates, Inc. 111 University Drive East, Suite I 05 College Station, Texas 77840 (979) 846-840 I Contact: Chris H arris, P.E. The ADT Self Storage is a 5.005 acre tract located at 7103 Rock Prairie Road on the northern side of the road north of the Brazos Valley solid waste facility. The subject site is the first phase of a two part storage faci lity phased development. The prope1iy is an unplatted parcel of land. T he preliminary plat wi ll be submitted by Kirnl ey-Horn and Associates, Inc. with the ADT Self Storage -Phase 1, C ivil Engineering Plans. Location The subject site li es within the Lick Creek watershed and is located along the northern boundary of the Lick Creek watershed. The need for a Type l detention fac ility was to be evaluated based on the location of the prope1iy in the Lick C reek watershed. The site drains in a southeasterl y direction w ith an average slope of l % toward the Rock Prairie Road borrow ditch. Runoff then discharges into an existing 30" corrugated metal pipe that transports the runoff discharge underneath Rock Prairie Road south to an existing channel. The site is cutTently undeveloped with portions being shoti-grasslancl and wooded. The subject site is located inside the City of Coll ege Station city limits. No portion of the site is located within the 100-year floodplain based on the FIRM (Flood Insurance Rate Map) Panel Map for Brazos County, Map No. 48041 C0201D included in Appendix A. Hydrologic Characteristics The ADT Self Storage site falls wi thin the Lick Creek watershed. Information about the basin was obtained from Figure B-10 of the City of College Station Drainage Manual. The site contains a Zulch (ZuB) fine sanely loam soil with I to 3 percent slopes. Currently, the subject site is an undeveloped grassland and wooded tract that sheet flows in a southeasterly direction and empties into the northern Rock Prairie Road borrow ditch. The ditch flows southeasterly to an existing 30" corrugated metal pipe that cuts under Rock Prairie Road. The adjacent properties do not drain onto the subject site. A portion of the subject site does sheet flow onto adjacent properties in existing conditions. The fully developed site wil l have two phases of a storage unit fac ility with an impervious cover of 70.9%. The grades on the site will range from 0.5% to 2% and designed to slope toward the detention pond. Both the eastern and western portions of the site will sheet flow into the detention pond. The detention pond will then discharge into the Rock Prairie Road botTow ditch. The on-site detention faci lity was designed using HEC-HMS 3.2 and the NRCS curve number method with criteria consistent w ith the City of Coll ege Station Unified Stonnwater Design Guidelines Dated February 2008. The hydrologic analysis for the subject site, using HEC-HMS 3.2, can be found in Appendix B. The drainage areas used in the HEC-HMS 3.2 analysis can be seen in the plan sheet entitled HEC-HMS M odels Drainage Area Maps located in Appendi x B of the report. Hydraulic Criteria As designed, the runoff fr om the western porti on of th e site will fl ow in the paved drive ai sles where it will then be conveyed south into the proposed detention pond through a 20ft non-curb section. The eastern portion of the site will flow in the paved dri ve aisles where it will then be conveyed into a ten foot curb inlet. Fro m the curb inl et, the water will then travel within a 30" RCP fo r approximately 175". The proposed pond outfa ll structure has a 24" RC P, with an invert elevation of 269.30, and a 4.25ft long sharp-crested weir at an elevati on of 271.36. The orifice opening for th e 24" RCP will be restricted to an effective area of 1.23 square feet by means of a steel plate th at will be centered 0.83' above th e fl owline of the 24" RCP. The outfall has been designed to not increase fl ows entering the ex isting 30" culvert in the 2, 5, I 0, 50, and l 00 year storm events. The top of the outfall structure acts as the detention pond emergency overflow spillway. The emergency overfl ow spillway is a 26.25ft long sharp-crested weir at an elevati on of272.37. The detention pond will be located in the southwestern portion of the site and is sized to hold 0.796 acre- feet of storage fo r the l 00 year design storm. The detenti on pond was designed to store runoff for the entire site in developed conditions. The drainage areas emptying into the detention pond will inclu de developed flows from the subject prope1iy. The no1i hem and eastern edges of the site will sheet flow onto the adjacent property where it will ultimately fl ow southeasterly toward the existing culve1i. Flows from these areas will not exceed existing flows to these properties. The drain age system is designed to convey, collect, and release runoff from the ADT Self Storage -Phase 1 at fl ows that do not increase existing flows, based on each of the design storms, entering into the existing 30" roadway culve1i. Coordination and Permitting No coordination of sto rmwater with entities out side the Cit y of College Station will be required. Included by Refe1·ence T he fo llowing documents are included by reference: • 26-page drainage report dated October 20, 2008. • ADT Self Storage -Phase l , Civil Engin eeri ng Pl ans by Kimley-Horn and Associates, Inc. '"This report for the drainage design of ADT Self Storage was prepared under mv supe1vision in accordance with provisions of rh e B1yan/College Station Unified Drainage Design Guidelines for the owners of the property. All licenses and permits required by any and all state and federal regLilato1y agencies for th e proposed drainaoe improvements have been issued " State of Texas No. Appendix A FEMA FIRM Map Appendix B HEC-HMS 3.2 Hydrologic Analysis ADT Self Storage Drainage Analysis Drainage Information Sub-basin Sub-basin Percent Slope Time of Width Base Curve Name Area Impervious (ft/ft) Number Concentration (ft) (acres) (%) (m in) Al 540 6.12 0 0.011 79 29.1 Existing A2 680 17.06 0 0.018 79 31.5 JAl Total Acreage 23.18 DA-1 330 4.28 70.9 0.009 94 10.0 Proposed 0 -1 215 1.84 0 0.015 79 24.6 0 -2 680 17.06 0 0.018 79 29.l JAl Total Acreage 23.18 Detention Pond 90 0.41 100 0.008 ADT Self Storage Drainage Analysis 2-Year Hydrology Results Percent Total Rainfall Total Runoff Total Time of Maximum Sub-basin Area Infiltration Flowrate Name (acres) Impervious (in) Depth Peak {%} (in) (in) {hh :mm) (cfs) Al 6.12 0 4.50 2.38 2.12 13:22 9.8 Existing A2 17.06 0 4.50 2.38 2.12 13:20 28 .2 JAl 13:21 38.0 DA-1 4.28 70.9 4.50 3.8l 0.68 13:07 15.1 0-1 1.84 0 4.50 2.38 2.12 13:17 3.3 0-2 17.06 0 4.50 2.38 2.12 13:20 28.2 Proposed JAl 13:20 38.0 Detention Pond 0.41 100 0.00 0.00 0.00 13:23 6.6 ADT Self Storage Drainage Analysis 10-Year Hydrology Results Percent Total Rainfall Total Runoff Total Time of Maximum Sub-basin Area Name (acres) Impervious (in) Depth Infiltration Peak Flowrate (%) (in) (in) (hh:mm) (cfs) Al 6.12 0 7.40 4.95 2.45 13:21 20.3 Existing A2 17.06 0 7.40 4.9 5 2.45 13:20 58.5 JAl 13:20 78.7 DA-1 4.28 70.9 7.40 6.69 0.71 13:07 25.7 0-1 1.84 0 7.40 4.95 2.45 13:17 6.8 0-2 17.06 0 7.40 4.9 5 2.45 13:20 58.5 Proposed JAl 13:20 76.6 Detention Pond 0.41 100 7.40 0.00 0.00 13:21 11.8 ADT Self Storage Dra in age Analysis 25-Year Hydrology Results Sub-basin Area Percent Total Rainfall Total Runoff Total Tim e of Maximum Name (acres) Impervious Depth Infiltration Peak Flowrate (%) (in) (in) (in) {hh:mm) (cfs) Al 6.12 0 8.40 5.88 2.52 13:21 24.0 Existing A2 17.06 0 8.40 5.88 2.52 13:20 69.2 JAl 13:20 93 .l DA-1 4.28 70.9 8.40 7.68 0.72 13:07 29 .3 0-1 1.84 0 8.40 5.88 2.52 13 :16 8.0 Proposed 0 -2 17.06 0 8.40 5.88 2.52 13:20 69 .2 JAl 13 :20 91 .5 Detention Pond 0.41 100 8.40 0.00 0.00 13 :19 14.8 ADT Self Storage Drainage Analysis SO-Year Hydrology Results Percent Total Runoff Total Time of Maximum Sub-ba sin Area Total Rainfall Infiltration Flowrate Sub-basin Name Impervious (in) Depth Peak (acres) {%) (in) (in) {hh:mm) (cfs) Al 6.12 0 9.80 7.20 2.60 13:21 29 .1 Existing A2 17.06 0 9.80 7.20 2.60 13:19 84.1 JAl 13:20 113.1 DA-1 4.28 70.9 9.80 9.07 0.73 13:07 34.3 0-1 1.84 0 9.80 7.20 2.60 13:16 9.7 0-2 17.06 0 9.80 7.20 2.60 13:19 84 .1 Proposed JAl 13:19 112.4 Detention Pond 0.41 100 9.80 0.00 0.00 13:18 18.8 ADT Self Storage Drainage Analysis 100-Year Hydrology Results Percent Total Rainfall Total Runoff Total Time of Maximum Su b-bas in Area Infiltration Sub-basin Name (a cre s) Impervious (in) Depth Peak Flowrate (%) (in) (in) (hh:mm) (cfs) Al 6.12 0 11.00 8.35 2.65 13:21 33.6 Existing A2 17.06 0 11.00 8.35 2.65 13:19 96.9 JAl 13:20 130.3 DA-1 4.28 70.9 11.00 10.27 0.73 13:07 38.6 0-1 1.84 0 11.00 8.35 2.65 13:16 11.2 Proposed 0 -2 17.06 0 11.00 8.35 2.65 13:19 96.9 JAl 13:19 130.3 Detention Pond 0.41 100 11.00 0.00 0.00 13:17 22 .5 ADT Self Storage Drainage Analysis 2-Year Hydraulic Junction Results Existing Proposed Node Name JAl Detention Pond JAl Max Water Time of Max Surface Elevation M ax HGL Area (ft) (hh:mm) (sq ft) 27103 13:07 13439 Max Volume (acre-feet) 0.266 Peak Outflow (cfs) 38.0 6.6 38.0 ADT Self Storage Drainage Analysis 10-Year Hydraulic Junction Results Existing Proposed Node Name JAl Detention Pond JAl Max Water Time of Max Surface Eleva t ion Max HGL Area (ft) (hh:mm) (sq ft) 271.78 13:07 15081 Max Volume (acre-fe et) 0.51 Peak Outflow (cfs) 78.7 11.8 76.6 ADT Self Storage Drainage Analysis 25-Year Hydraulic Junction Results Existing Proposed Nod e Name JAl Detention Pond JAl Max Wat er Time of Max Surface Elevation Max HGL Area (ft) (hh:mm) (sq ft) 271.97 13 :07 15501 Max Volume (a cre-feet) 0.572 Peak Outflow (cfs) 93.l 14.8 91.5 ADT Self Storage Drainage Analysis SO-Year Hydraulic Junction Results Existing Proposed Node Name JAl Detention Pond JA l M ax Water Ti me of El eva tion M ax HGL (ft) (hh:mm) 272.19 13:07 M ax Surface Area (sq ft) 15990 Max Volume (ac re-feet) 0.655 Peak Outflow (cfs) 113.1 18.8 112.4 ADT Self Storage Drainage Analysis 100-Year Hydraulic Junction Results Existing Propose d Node Name JAl Detention Po nd JAl Max Water Time of Max Surface Elevation Max HGL Area (ft) (hh:mm) (sq ft) 272.37 13:07 16392 Max Vo lume (acre-feet) 0.724 Peak Outflow (cfs) 130.3 22.5 130.3 Existing Rock Prairie Road Borrow Ditch Information Length Link Name (ft) Exist Borrow Ditch 417 Shape ADT Self Storage Drainage Analysis Roughness Trapezoid 0.045 ADT Self Storage Drainage Analysis Upstream Invert Elevation 269.3 Downstream Invert Elevation 266 Channel Height Slope (ft) (%) 0.79 2.50 Bottom Width (ft) 3 Right-Left-hand hand Side Side Slope Slope 3.5 3.5 ADT Self Stora ge Drainage Analysis 2-Year Exis ting Bo rrow Ditch Res ults Time of Max Time to Max Link Name Height Max Flow Peak Water Peak Velocity (ft) (cfs) (hr) (fps) Velocity Depth (h r) (ft) Exist Borrow Dit ch 2.50 6.63 13:26 1.77 13:26 0.69 10-Year Existing Borrow Ditch Results Time of Max Time to Max Height M ax Flow Peak Wat er Link Name Peak Velocity (ft) (cfs) (hr) (fps) Velocity Depth (hr) (ft) Exist Borrow Ditch 2.50 11.78 13:24 2.06 13:24 0.92 25-Yea r Existing Borrow Ditch Res ults Time of Max Time to Max Link Name Height Max Fl ow Peak Velocity Peak Water (ft) (cfs) (hr) (fps) Ve locity Depth (hr) (ft) Exist Borrow Ditch 2.50 14.74 13:22 2.19 13:22 1.02 SO-Year Existing Borrow Ditch Results Time of Max Heigh t Max Flow Time to Max Link Name Pea k Velocity Peak Water (ft) (cfs) (hr) (fps) Velocity Depth (hr) (ft) Exist Borrow Ditch 2.50 18.80 13:20 2.34 13:20 1.15 100-Year Existing Borrow Ditch Results Time of Max Height Max Fl ow Time to Max Link Name Peak Ve locity Peak Water (ft) (cfs) (hr) (fps) Ve locity Depth (hr) (ft) Propose d Exis t Borrow Ditch 2.50 22.44 13:19 2.45 13:19 1.25 ~ ~ QI 16 14 12 10 !:ll 8 "' ..c: u Ill c 6 4 2 0 2-Year Design Storm Detention Pond Inflow vs. O utflow Hydrographs _____________ T ___ I -· ~ I I . ·-------·---··--------·-·---------f------------------------· I I I I I I ' - I . \ I ' ' \ I I \ ----1 ' ' \ I ' j \ I \ I >-----· \ I ~ ~ -' 0:00 6:00 12:00 18:00 Time (hrs) -- --Inflow - -- -Outflow 0:00 :[ GJ 10-Year Design Storm Detention Pond Inflow vs. Outflow Hydrographs 30 ---------------T I i 25 -+------------t---------------------+----------; ~ 15 -f---------------------------------------.----------t------------i Ill .c u Ill c ,. 10 ----------------------------------'-' _,__, -------------------------' ' I \ ' ' I ' I \ I \ 5 ~----------------------+-.!--, --I----',-,------------+------------; I \ I \ \ L 0:00 6:00 ------ 12:00 Time (hrs) 18:00 0:00 --Inflow - - - -Outflow 20 -~ ..!::. Cll tlQ 15 .. RI ..c v VI cs 10 5 l 0 -,----· 25-Year Design Storm Detention Pond Inflow vs. Outflow Hydrographs ---, -----1- ---t I u I l I t I t I I t --·-·---·-·--·--------t- I ' I ' I ' I \ • ' \ I \ • I ' \ I \ ., ' \ - 0:00 6:00 12:00 18:00 Time(hrs) -- --Inflow ----Outflow 0:00 35 30 25 -Ill 20 -~ ~ llO ... "' .J: v Ill 15 c 10 5 0 SO-Vear Design Storm Detention Pond Inflow vs. Outflow Hydrographs --·----------r - I --------------·---- 1\ I l I I -------· ' I I I I I I I I ' I ' -· I I ' I \ I \ ' J \ ' \ -----------·--___J-j ~ 0:00 6:00 12:00 18:00 Time (hrs) --Inflow -- - ---Outflow 0:00 40 35 30 25 -Ill -~ Cll ~ 20 "' ..c I.I Ill l5 15 10 5 0 ·-· 100-Year Design Storm Detention Pond Inflow vs. Outflow Hydrographs ----·---·-------t I~ ·--------' I I I I I I I ' ' I I ' I ' I ' I ' -· I ' ' \ j ' \ ' • I .. ---~'/ ~ 0:00 6:00 12:00 18:00 Time (hrs) --Inflow - - - -Outflow 0:00 r-----·-----------------------------------·----------~ ~ u QI 1111 ... Ill .J::. u "' 0 40.00 r 35.00 ----- - ----- 30.00 --------- 25.00 20.00 15.00 2-Year Outfall (JAl) Hydrographs T ----------~----------------- I I ----+-----------+ I -------+----·------- -------+------~ ----+------- -------- --------------------11------------i----- ·-------·--------+----------< ' ' ' \ I 10 00 t ---- - ----+-- I I 500 I • ----+------------< I -----i---------,, 0.00 ~/ I -i---------.................... :;,;;;;;.o .... ---==----·--+--------·-----+-------·-------- 0:00 6:00 12:00 18:00 0:00 Time (hrs) --Pre-development - - - -·Post-Development L ____________________________ __, i QI ... ... ca .:: :;( iS 10-Year Outfall (JAl) Hydrographs 80.00 . ---. 70.00 --------i--·-----·-----------r- -------------~-~--~~~------~~! -~~~-~-~ 60.00 50.00 40.00 I \-----------·-------·-·-· --·-·-·------ I tl··-----------------+---------- 1 --------------------------------tt--+------------+- 1 --------------t I 30.00 I I --------------·· ----·-·------1-----------------------t----------- 20.00 ----------·-- I 10.00 ------+----~'o-----+-·- 1 0.00 .~-------~ ...... ~~----+----· 0:00 6:00 12:00 18:00 0:00 Time (hrs) --Pre-development ----Post-Development ~------------------------------------------------' I I I I I I f 25-Year Outfall (JAl) Hydrographs ::~-----~-~~~~--.~~~~~~-:-~-~~~==----~ I 80.00 r--------------------------------+-11-a----- i I 70.00 r-·--------------·- 1 I I 60.00 1-- ! I I 1---------------·-----+lt--11----·------------t--·------------ --Pre-development - - - -Post-Development ~ so.oo L-------------------------tl-ll-------------11-------------< '----------' ~ I ~ I I 40.00 I I 30.00 -r- 20.00 l-... I 10.00 --------------- -----------t-- ------- ___ ,, _____________ l _______________ --11·-t----+------------< 0.00 -~. --------...i...-.-.!~~= ------+--------------!---------- 0:00 6:00 12:00 Time {hrs) 18:00 0:00 SO-Vear Outfall (JA1) Hydrographs 120.00 r · r---_______ T _____ _ --------- I 100.00 1--· -------t------ 80.00 ----· ~ QI ~ 60.00 ftl ~ :;< 0 40.00 -l- 1 I 20.00 +----- 1 0.00 0:00 1 ---·-· t---------tt-0--------+----- ! --Pre-development - ---Post-Development ----f----------------0------------.___ _____ _, ---------_J_ __________________ ---+----- ------r---- 6:00 12:00 Time (hrs) 18:00 0:00 100-Vear Outfall (JAl) Hydrographs 140.oo 1--------------------___ T _____ _ I I I 120.00 +--------- ! 100.00 l-----·------------------------------++------------i ' I I wm ~-------------------------~-~----------~-----·-------~-P~d~~P~~ ~ i ~ I ~ I 60.00 -1---------· ----- 1 I I 40.00 ·t-- 1 ! I 20.00 t·---·----· i I ! 0.00 -1i---------~~~".:::::: 0:00 6:00 - - - -Post-Development 12:00 18:00 0:00 Time (hrs) ---------------------------------------------------------' Appendix C 18" RCP Driveway Cul verts Calculati ons 25 -Year Design Storm culvert Calculator Two 18 " culverts under driveway l calcul ator output should be ve rified prior to design use Entered Data : s hape .......................... . Number of Barrels .............. . So lving for .................... . Cha rt Number ................... . s eal e Numb e r ................... . circular 2 Headwat er 1 1 chart Description .............. . Scal e Description .............. . CO NCRETE PIPE CUL VERT; NO BEVELED RING ENTRANCE SQUARE EDGE ENTRANCE WITH HEADWAL L overtoppi ng .................... . Fl owrate ....................... . Manning 's n .................... . Roa dway El evation .............. . Inl et Elevation ................ . Outlet Elevation ............... . Diamete r ....................... . Le ngth ......................... . Entrance Loss .................. . Tai l wate r ...................... . Co mput ed Resul ts : Headwater ...................... . slope .......................... . veloci ty ....................... . Messages : Out let head > I nlet head. Com puting outlet Control headwater . Outlet not s ubmerged. Normal Depth : 18.0000 in Critical Depth : 12 .6458 in Flow i s s ubcri tical . Normal depth > critical depth . Tai lwater depth < normal depth. M2 drawdown profile . off 14.8000 cfs 0 . 0130 271 .6400 ft 269.0700 ft 268 .8200 ft 18.0000 in 66 .1600 ft 0.6000 0.8050 ft 271 .55 56 ft outlet control 0.0038 ft/ft 5.5786 fps Tailwater depth <= critical depth . Depth computed with direct step method starting at criti cal depth . Headwater: 271 .5556 ft DI S-HEAD-IN LET OUTLET CHARGE WATER CONTROL CONTROL FLOW NORMAL CRITICAL OUTLET Fl ow ELEV. DEPTH DEPTH TYPE DEPTH DEPTH VEL. DEPTH cf s ft ft ft in in fp s ft o. 50 269 .45 0.24 0.38 Ml 2.41 18.00 0.26 0 . 20 1. 00 269 .46 0.35 0. 39 Ml 3.38 18 .00 0 . 52 0. 28 1. 50 269 . 50 0.43 0 .41 NA 4.14 3 .86 2.45 0. 34 2.00 269. 58 0. 51 0 .43 NA 4.78 4 .48 2 .66 0.40 2.50 269 .64 0 . 57 0.45 NA 5.36 5.02 2 .83 0.45 3.00 269 .70 0 .63 0.48 NA 5.89 5.51 2 .98 0.49 3.50 269 .76 0.69 0. 51 NA 6 . 39 5.97 3 .11 0.53 4 .00 269 . 81 0 .74 0. 5 5 NA 6.86 6 .40 3 .23 0. 57 4 . 50 269 .86 0 .79 0.60 NA 7.32 6.80 3.33 0.61 5.00 269 .91 0 .84 0.65 NA 7.76 7.19 3.43 0.65 5.50 269 . 96 0.89 0. 71 NA 8 .19 7.55 3 .52 0.68 6.00 270. 00 0.93 0. 77 NA 8 .60 7.90 3.60 0. 72 6. 50 270 . 05 0 .98 0.85 NA 9 .02 8.24 3.67 0.75 7.00 270 .10 1. 03 0.93 NA 9 .42 8.57 3.74 0.79 7.50 270.14 1. 07 1. 02 NA 9 .83 8.88 3.80 0.82 8.00 270 .19 1.12 1.11 NA 10. 23 9.19 3.86 0.85 8 .50 270.28 1.16 1. 21 M2 10.63 9.19 4 .40 0.89 9.00 270 .27 1. 20 0 .91 NA 11.04 9. 77 3 . 96 0 .92 9 . 50 270. 50 1. 25 1. 43 M2 11. 45 9 . 77 4.68 0 .95 10 .00 270. 60 1. 29 1. 53 M2 11. 87 9 . 77 4. 77 0.99 10 . 50 270 . 71 1. 33 1. 64 M2 12.29 9. 77 4.85 1. 02 11.00 270. 84 1. 38 1. 77 M2 12.73 9 . 77 4.94 1. 06 Page 1 TAILWATER VEL. DEPTH fps ft 0.00 0 .81 0 .00 0 .81 0.00 0 .81 0.00 o. 81 0 .00 0 .81 0.00 0. 81 0.00 0.81 0.00 0.81 0 .00 0.81 0 .00 0.81 0 .00 0. 81 0 .00 0. 81 0 .00 0 .81 0.00 0 .81 0 .00 0 . 81 0 .00 0 .81 0 .00 0.81 0 .00 0.81 0 .00 0 .81 0 .00 0 .81 0 .00 0.81 0 .00 0 .81 11. 50 270. 93 1. 42 1. 86 M2 13 .19 9. 77 5.02 1.10 0.00 0.81 12.00 270.99 1.46 1. 92 M2 13. 68 9. 77 5 .11 1.14 0.00 0.81 12.50 271. 05 1. 51 1. 98 M2 14. 21 9. 77 5.19 1.18 0.00 0.81 13 .00 271. 44 1. 84 2.37 M2 18.00 9. 77 3.68 1. 50 0.00 0.81 ;I.3.50 271. 47 1. 87 2.40 M2 18.00 9. 77 3.82 1. 50 0.00 0.81 14.00 271. 50 1. 89 2.43 M2 18.00 9. 77 3. 96 1. 50 0.00 0.81 14. 50 271. 54 1. 92 2.47 M2 18.00 9. 77 4.10 1. 50 0.00 0.81 15.00 271. 57 1. 95 2.50 M2 18.00 9. 77 4.24 1. 50 0.00 0.81 15. 50 271. 60 1. 97 2.53 M2 18.00 9. 77 4.39 1. 50 0.00 0.81 16.00 271. 05 1. 98 0.00 NA 18.00 18.00 4.53 1. 50 0.00 0.81 16. 50 271. 05 1. 98 0.00 NA 18.00 18.00 4.67 1. 50 0.00 0. 81 17.00 271. 04 1. 97 0.00 NA 18.00 18.00 4.81 1. 50 0.00 0. 81 17. 50 271. 05 1. 98 0.00 NA 18.00 18.00 4.95 1. 50 0.00 0. 81 18.00 271.10 2.03 0.00 NA 18.00 18.00 5.09 1. 50 0.00 0. 81 18.50 271.16 2.09 0.00 NA 18.00 18.00 5.23 1. 50 0.00 0.81 19.00 271. 22 2.15 0.00 NA 18.00 18.00 5.38 1. 50 0.00 0.81 19. 50 271.28 2. 21 0.00 NA 18.00 18.00 5.52 1. 50 0.00 0.81 20.00 271. 35 2.28 0.00 NA 18.00 18.00 5.66 1. 50 0.00 0.81 20. 50 271. 41 2.34 0.00 NA 18.00 18.00 5.80 1. 50 0.00 0.81 21.00 271. 48 2.41 0.00 NA 18.00 18.00 5.94 1. 50 0.00 0.81 21. 50 271.54 2.47 0.00 NA 18.00 18.00 6.08 1. 50 0.00 0.81 22.00 271. 61 2.54 0.00 NA 18.00 18.00 6. 22 1. 50 0.00 0.81 Page 2 SECTION IX APPENDIX D -TECHNICAL DESIGN SUMMARY The Cities of Bryan and College Station both require storm drainage design to follow these Unified Stormwater Design Guidelines. Paragraph C2 of Section Ill (Administration) requires submittal of a drainage report in support of the drainage plan (stormwater management plan) proposed in connection with land development projects, both site projects and subdivisions. That report may be submitted as a traditional prose report, complete with appli cable maps, graphs, tables and drawings, or it may take the form of a "Technical Design Summary". The format and content for such a summary report shall be in substantial conformance with the description in this Appendix to those Guidelines. In either format the report must answer the questions (affirmative or negative) and provide, at minimum, the information prescribed in the "Technical De sign Summary" in th is Appendix. The Stormwater Management Technical Design Summary Report shall in clude several parts as listed below. The information ca lled for in each part must be provided as appli cable. In additi on to the requirem ent s for the Executive Summary, this Append ix in cludes several pages detail ing the requirements for a Technica l Des ign Summary Report as forms to be completed. These are provided so that they may be copied and completed or scanned and digitized. In addition, electronic versions of the report forms may be obtained from th e City. Requirements for the means (medium) of sub mittal are the same as for a conventional report as detailed in Section 111 of these Guidelines. Note: Part 1 -Executive Summary must accompany any drainage report requ ired to be provided in connection with any land development project, regardless of the format chosen for said report. Note: Parts 2 through 6 are to be provided via the forms provided in this Appendix. Brief statements should be included in the forms as requested , but additional inform ation should be attached as necessary. Part 1 -Executive Summary Report Part 2 -Project Administration Part 3 -Project Characteristics Part 4 -Drainage Concept and Design Parameters Part 5 -Plans and Specifications Part 6 -Conclusions and Attestation STORMWATER DESIGN GUIDELINES Effective February 2007 Page 1 of 26 APPENDIX D: TECH. DESIGN SUMMARY As Revised February 2008 SECTION IX APP ENDIX D -TECHNICAL DESI GN SUM MARY STORMWATER MANAGEMENT TECHNICAL DESIGN SUMMARY REPORT Part 1 -Executive Summary This is to be a brief prose report that must address each of the seven areas listed below. Ideally it will include one or more paragraphs about each item. 1 Name, address, and contact information of the engineer submitting the report, and of the land owner and developer (or appli cant if not the owner or developer). The date of submittal should also be included. 2 Identifi cation of th e size and general nature of the proposed project, including any proposed project phases. This paragraph should also include reference to applications that are in process with either City: plat(s), site plans, zoning requests, or clearing/grading permits, as well as reference to any application numbers or codes assigned by the City to such request. 3 The location of th e project should be describ ed . Thi s should identify the Named Regulatory Watershed(s) in which it is located, how the entire project area is situated therein, whether th e property straddles a watershed or basin divide, the approximate acreage in each basin, and whether its position in the Watershed dictates use of detention design . The approximate proportion of the property in th e city limits and wi thin th e ET J is to be identified, in cluding whether the property straddles city jurisdictiona l lines. If any portion of the property is in floodplains as describ ed in Flood Insurance Rate Maps published by FEMA that should be disclosed. 4 The hydrologic characteristics of the property are to be described in broad terms: existing land cover; how and where stormwater drains to and from neighboring properties; ponds or wetland areas th at tend to detain or store stormwater; existing creeks, channels, and swales crossing or serving the property; all existing drainage easements (or ROW) on the property, or on neighboring properties if they service runoff to or from the property. 5 The general plan for managing stormwater in th e entire project area must be outlined to include the approximate size, and extent of use, of any of the following fea tures: storm drains coupled with streets; detention I re ten tion faci lities; buried conveyance conduit independent of stre ets; swales or channels; bridges or culverts; outfalls to prin cipal watercourses or their tributaries; and treatment(s) of existing watercourses. Also, any plans for reclaiming land within floodplain areas mu st be outlined. 6 Coordination and permitting of stormwater matters must be addressed. This is to include any specialized coordina tion that has occurred or is planned with other entities (local, state, or federal). This may include agencies such as Brazos County government, the Brazos River Authority, th e Texas A&M University System, the Texas Department of Transportation, th e Texas Commission for Environmental Quality, th e US Army Corp s of Enginee rs , the US Environmental Protection Agency, et al. Mention must be made of any permits, agreements, or understandings th at pertain to the proj ect. 7 Reference is to be made to th e fu ll drainage report (or the Technical Design Summary Report) which th e executive summa ry represents. The principal elements of the main report (and its length), including any maps, drawings or constructi on documents, should be itemized. An example statement might be : "One 2 -page drainage report dated October 20, 2008, one set of construction drawings ( 16 sheets) dated October 20, 2008, and a 26 -page specifications document dated October 20, 2008 comprise the drainage report for thi s project." STORMWATER DES IGN GUIDELINES Effective February 2007 Page 2 of 26 APPENDIX D: TECH. DESIGN SUMMARY As Revised February 2008 SECTION IX APPENDIX D -TECHNICAL DESIGN SUMMARY Part 2 -Project Administration I Start (Page 2.1) Engineering and Design Professionals Information Eng ineeri ng Firm Name and Address: Ju risdiction City: Bryan Kimley-Horn and Associates, Inc. x College Station 111 University Drive East, Suite 105 College Station, Te xas 77840 Date of Submittal: Oct. 20, 2008 Lead Engineer's Name and Contact lnfo.(phone, e-mail, fax): Other Chris Harris, P.E. (979) 846-8401 Chris. Harris@kimley-hom com Supporti ng Engineering I Consulting Firm(s): Other contacts: Developer I Owner I Applicant Information Developer I Applica nt Name and Address : Pho ne and e-mail: DCB Construction 909 E. 62nd Ave nue Contact. Mark Delgado Denver, Colorado 80216 {303) 287-5525 Property Owner(s) if not Developer I Applica nt (&address): Phone and e-mail: Project Identification Development Name: ADT Self Storage Is subject property a site proj ect, a sin gle-phase subd ivision , or part of a multi-phase subd ivision? Part of a multi-Q.hase subdivision If multi-phase, subject property is phase 1 of 2 Legal description of subject property (phase) or Project Area: (see Section II, Paragraph B-3a) A000901 Thomas Carruthers (/CL) Tract 5.1 , Acres 5.01 VLB # 125065 If su bject 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. General Location of Project Area, or subject propert y (phase) The tract is located at 7103 Rock Prairie Road on th e northern side of the road and north of the Brazos Valley solid waste facility. In City Limits? Yes Extraterritorial Jurisdiction (acreage): Not AQ.Q.licable Brya n: acres . Bryan: College Station: 5.005 acres. College Stati on : Acreage Outside ET J: Part 2 -Project Administration I Continued (page 2.2) Project Identification (continued) STORMWATER DESIGN GUIDELINES Effective February 2007 Page 3 of 26 APPENDIX D: TECH . DESIGN SUMMARY As Revised February 2008 SECTION IX APPENDIX D -TECHNICAL DESIGN SUMMARY Roadways abutting or within Project Area or Abutting tracts, platted land, or built subject property: developments: Rock Prairie Road A00090 1 Thomas Carruthers (/CL), Tract 5, Acres 66.39, Undivided Interest A000901 Thomas Carruthers (!CL), Tract 45, Acres 1. 74 A000901 Thomas Carruthers (!CL), Tra ct 46, Acres 3.37 Named Regulatory Watercourse(s) & Watershed(s): Tributary Basin( s) Lick Creek Watershed Area Plat Information For Project or Subject Property (or Phase) Preliminary Plat File# Fin al Plat Fil e # Date: Name: Status and Vol/Pg: If two plats, second name File # Sta tu s Date: Zoning Information For Project or Subject Property (or Phase) Zoning Type: C-3 Exis ting or Proposed? Existing Case Code: Not AQQlicable Case Date Not AQQlicable Statu s Not Applicable Zoning Type: A-0 Existing or Proposed? Existing Case Code Not AQQlicable Case Date Not AQQlicable Status: Not Applicable Stormwater Management Planning For Project or Subject Property (or Phase) Pl anning Conference(s) & Date(s): Participants: Kimley-Horn and Associates, Inc. June 25, 2008 DCB Construction Jim Singleton Architects Preliminary Report Req uired? No Submittal Date Review Date Review Comments Addressed? Yes --No --In Writing? When? Compliance With Preliminary Drainage Report. Briefly describe (or attach documentation explaining) any deviation(s) from provisions of Pr eli minary Drainage Report, if any. Not Applicable Part 2 -Project Administration I Con tinued (page 2.3) Coordination For Project or Subject Property (or Phase) STORMWATER DESIGN GUIDELINES Effective February 2007 Page 4 of 26 APPENDIX D: TECH. DESIGN SUMMARY As Revised February 2008 SECTION IX APPENDIX D -TECHNICAL DESIGN SUMMARY Note: For any Coordination of stormwater matters indicated below, attach documentation describing and substantiating any agreements, understandings, contracts, or approva ls. Coordination Dept. Co ntact: Date: Subject: With Other NIA NIA NIA NIA Departments of Jurisdiction City (Bryan or College Station) Coordination With Summarize need(s) & actions taken (include contacts & dates) Non-jurisdiction City Needed? Yes No x -- Coordination with Summarize need(s) & actions taken (i nclud e contacts & dates): Brazos County Needed? Yes --No _l$___ Coordination with Summarize need(s) & actions taken (includ e contacts & dates) TxDOT Needed? Yes --No _l$___ Coordination with Summari ze need(s) & action s taken (inclu de contacts & dates): T AM US Needed? Yes --No _l$___ Permits For Project or Subject Property (or Phase) As to stormwater management, are permits required for the proposed work from any of th e entities li sted bel ow? If so, sum marize status of efforts toward that objecti ve in spaces below. Entity Permitted or Status of Actions (include dates) Approved? US Army Corps of Engineers Not Applicable No _x_ Yes -- US Environmental Protectio n Agency Not Applicable No _x_ Yes -- Texas Commission on Environmental Quali ty Not Applicable NO/ included in submittal. No --Yes _x_ Brazos River Authority Not Applicable No _x_ Yes -- Part 3 -Property Characteristics I Start (Page 3.1 ) Nature and Scope of Proposed Work STORMWATER DESIGN GUIDELINES Effective February 2007 Page 5 of 26 APPENDIX D: TECH. DESIGN SUMMARY As Revised February 2008 SECTION IX APPENDIX D -TECHNICAL DESIGN SUMMARY Existing: Land proposed for development currently used, including extent of impervious cover? Undeveloped grassland and wooded tract. Site __ Redevelopment of one pla tted lot, or two or more adjoining platted lots. Development __ Building on a sin gle platted lot of undeveloped land. Project __ Building on two or more platt ed adjoining lots of undeveloped land. (select all _X_ Building on a sin gle lot, or adjoining lots, where proposed plat will not form applicable) a new street (but may include ROW dedication to existing streets) __ Other (explain) Subdivision __ Construction of streets and utilities to serve one or more platted lots. Development __ Construction of streets and utilities to serve one or more proposed lots on Project lands represented by pending plats. Site projects: building use(s), approximate floor space, impervious cover ratio. Describe Subdivisions number of lots by general type of use, linear feet of streets and Nature and drainage easements or ROW. Size of Phase /. Storage unit facility; 54,075 GSF floor area, 62.5% impervious cover. Proposed Project Phase II. Storage unit facility; 42,800 GSF floor area, 89.4% impervious cover. Fully Developed. Storage unit facility; 96,875 GSF floor area; 70.9% impervious cover Is any work planned on land th at is not platted If yes, explain or on land for which platting is not pending? _x_ No Yes -- FEMA Floodplains Is any part of subject property abutting a Named Regulatory Watercourse I No _X_Yes __ (Section 11, Paragrap h B 1) or a tributary thereof? Is any part of subject property in floodplain I No _X_Yes __ Rate Map 48041C02010 area of a FEMA-regulated watercourse? Encroachment( s) Encroachment purpose(s): __ Building site(s) __ Road crossing(s) into Floodplain __ Utility crossing(s) __ Other (explain): areas planned? No Yes x 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 Not Applicable. Part 3 -Property Characteristics I Continued (Page 3.2) Hydrologic Attributes of Subject Property (or Phase) Has an earlier hydrologic analysis been done for larger area including subject property? STORMWATER DESIGN GUIDELINES Effective February 2007 Page 6 of 26 APPENDIX D: TECH . DESIGN SUMMARY As Revised February 2008 SECTION IX APPENDIX D -TECHNICAL DESIGN SUMMARY Reference the study (&date) here, and attach copy if not already in Ci ty files. Yes -- Is th e stormwater management plan for the property in substantial conformance with the earlier study? Yes No If not, explain how it differs. If subject property is not part of multi-phase project, describe stormwater management No plan for the property in Part 4. _x_ 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. The analysis anticipated developed conditions for both Phase I and Phase II and a single detention pond was sized to serve both phases. On-site runoff will be captured in the detention pond located on the southern portion of the site, and then discharged into the Rock Prairie Road drainage ditch. Do existing topographic features on subject property store or detain runoff? x No --Yes Describe them (include approximate size, volume, outfall, model, etc). Any known drainage or flooding problem s in areas near subject property? x No Yes --Identify: Based on location of study property in a watershed , is Type 1 Detention (flood control) needed? (see Table B-1 in Appendix B) __ Detention is required. _X __ Need must be evaluated. __ Detention not required. What decision has been reached? By whom? Detention will be provided as determined by Kimley-Horn and Associates, If the need for Type Inc. hydrologic analysis. 1 Detention must How was determination made? be evaluated: HEC-HMS hydrologic analysis Part 3 -Property Characteristics I Continued (Page 3.3) Hydrologic Attributes of Subject Property (or Phase) (continued) Does subject property straddle a Watershed or Ba sin divide? _X_ No __ Yes If yes, describe splits below. Watershed or Basin STORMWATER DESIGN GUIDELINES Effective February 2007 In Part 4 describe design concept for handling this. Page 7 of 26 I Larger acreage I Lesser acreage I I APPENDIX D: TECH. DESIGN SUMMARY As Revised February 2008 SECTION IX APPENDIX D -TECH NICAL DESIGN SU MMARY Above-Project Areas(Section II, Paragraph 83-a) Does Project Area (project or phase) receive runoff from upland areas? _x_ No --Yes Size(s) of are a(s) in acres 1) 2) 3) 4) Flow Characteristics (each instance) (overland sheet, shallow concentrated , recognizable concentrated section(s}, small creek (non-regulatory}, regul atory Watercourse or tributary); Not Applicable. Flow determination: Outline hydrologic methods and assum ptions Not Applicable. Does storm runoff drain from public easements or ROW onto or across su bject property? _x_ No __ Yes If yes, descri be facilities in easement or ROW: Are changes in runoff characteristics subject to change in future? Explain Not Applicable. Conveyance Pathways (Section 11 , Paragraph C2) Must runoff from study property drain across lower properties before reaching a Regu latory Watercourse or tributary? No x Yes Describe length and characteristics of each conveyance pathway(s). Include ownership of property( ies). The runoff from the project site collects in the North Rock Prairie Road drainage ditch and travels East for approximately 300 feet before reaching a 30" corrugated metal culvert. The culvert discharges South, under Rock Prairie Road After discharging from the culvert, th e upstream runoff is conveyed through two properties owned by Brazos Valley Solid Waste by means of an existing channel. Part 3 -Property Characteristics I Continued (Page 3.4 ) Hydrologic Attributes of Subject Property (or Phase) (continued) Conveyance Pathways (continued) Do drainage If yes, for what part of length? % Created by? __ plat, or easements --instrument. If instrument(s), describe thei r provisions. exist for any part of STORMWATER DESIGN GUIDELINES Effective February 2007 Page 8 of 26 APPENDIX 0: TECH. DESIGN SUMMARY As Revised February 2008 SECTION IX APP ENDIX D -TECHNICAL DESIGN SUMMARY pathway(s)? _X_No Pathway Areas Nearby Drainage Facilities Yes Where runoff must cross lower properties, describe characteri stics of abutting lower property(ies). (Existing wa tercou rses? Easement or Consent aq uired?) The existing watercourse is a grass channel that conveys the water through the properties. Neither an easement or consent is required. Describe any built or improved drainage facilities ex isting near th e property (cu lverts, bridges, lined channels, buried conduit, swales, detention ponds, etc). There is an existing 30" corrugated metal pipe southeast of th e property Do any of these have hydrologic or hydraulic influence on proposed stormwater design? __ No _X __ Yes If yes , explain The proposed stormwater design fo r the property does not increase the existing flow entering the 30" corrugated metal pipe under Rock Prairie Road. Part 4 -Drainage Concept and Design Parameters I Start (Page 4.1) Stormwater Management Concept Discharge(s) From Upland Area(s) If runoff is to be received from upland areas, what design drainage feature s will be used to accommodate it and insure it is not blocked by future development? Describe for each area, flow section , or discharge poin t. STORMWATER DESIG N GUIDELINES Effective February 2007 Page 9 of 26 APPENDIX D: TECH. DESIGN SUMMARY As Revised February 2008 SECTION IX APPENDIX D -TECHNICAL DESIGN SUMMARY Discharge(s) To Lower Property(ies) (Section II , Paragraph E1) Does project include drainage features (existing or future) proposed to become public via platting? x No __ Yes Separate Ins trument? x No Yes Per Guidelines reference above, how will runoff __ Establishing Easements (Scenario 1) be discharged to neighboring property(ies)? _X_ 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# ) Scenario 2: Provide general description of how release(s) will be managed to pre-development conditions (detention, sheet flow, partially concentrated, etc.). (Attached Exhibit# ) The runoff from the property will be routed to the on-site detention pond and then released to the Rock Prairie Road drainage ditch. The release ra tes will be managed to pre-development conditions through the design of an orifice and we ir outlet structure that restricts the discharge of on-site runoff in order to maintain existing flows at the existing 30" corrugated metal culvert. 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)? x No __ Yes Explain and provide documentation. Discharge is to public Right-Of-Way. Part 4 -Drainage Concept and Design Parameters I Continued (Page 4.2) Stormwater Management Concept (continued) Within Project Area Of Multi-Phase Project Will project result Identify gaining Basins or Watersheds and acres shifting: in shifting runoff between Basins or between STORMWATER DESIGN GUIDELINES Effective February 2007 Page 10 of 26 APPENDIX D: TECH. DESIGN SUMMARY As Revised February 2008 SECTION IX APPENDIX D -TECHNICAL DESIGN SUMMARY Watersheds? What design and mitigation is used to compensate for increased runoff x No -Yes from gaining basin or watershed? How will runoff from Project 1. __ With facility(ies) involving other development projects. Area be mitigated to pre-2. __ Establishing features to serve overall Project Area. development conditions? 3. _X __ On phase (or site) project basis within Project Area . Select any or all of 1, 2, and/or 3, and explain below. 1. Shared facility (type & location of facility; design drainage area served; re lationship to size of Project Area) (Attached Exhibit# ) 2. For Overall Project Area (type & location of facilities): (Attached Exhibit# ) 3. By phase (or site) project: De scribe planned mitigation measures for phases (or sites) in subsequent questions of thi s Part. The proposed detention pond was de signed for th e runoff volume generated by the 100 year design storm for both proposed phases. Runoff from both developed phases will be conveyed to the designed detention pond. Are aquatic echosystems proposed? _x_ No __ Yes In wh ich phase(s) or project(s)? C'· u Q) c Are other Best Management Practices for reducing stormwater pollutants proposed? c if) (\l Q) ->-_x_ No ii __ Yes Sum marize type of BMP and extent of use: Q) 0 oz }xi 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 elem ents Channel features Swales --------~ <( Ditches --Inlets __ Valley gutters __ Outfalls __ Cu lvert features __ Bridges Other Part 4 -Drainage Concept and Design Parameters I Continued (Page 4.3) Stormwater Management Concept (continued) Within Project Area Of Multi-Phase Project (continued) Will Project Area include bridge(s) or culvert(s)? __ No _X_ Yes Identify type and general size and In which phase(s). In Phase 1, two 18" RCP will be installed under the project's entrance and exit driveway from Rock Prairie Road. STORMWATER DESIGN GUIDELINES Effective February 2007 Page 11 of 26 APPENDIX D: TECH. DESIGN SUMMARY As Revised February 2008 SECTION IX AP PEND IX D -TECHNICAL DESIGN SUMMARY If deten tion/retention serves (will serve) overal l Project Area, describe how it relates to subject phase or site project (physical location, conveyance pathway(s), constru ction sequence): The project site is graded to flow into the detention pond that is located on th e southwest portion of the site either by sheet flowing directly into the detention pond or indirectly through a 10' curb inlet connecting to a 30" RCP storm line. The detention pond will release the runoff from the site into the roadside drainage ditch to the south of the property The detention pond will be built simultaneously with Phase /. 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 su mm arize the di fference(s): Identify whether each of the types of drainage features listed below are included , extent of use, and general characteristics . C'· Typical shape? Trapezoidal I Su rfaces? Grass -u (!) rJ) rJ) Steepest side slopes Usual front slopes: Usual back slopes: ::J (!) <fl >-3.5H.·1v jxJ Flow line slopes: least 0.003fVft Typical distance from travelway: (!) 0 typical 0.008fVft greatest (Attached Exh ibit # ) ~z rJ) I -u m 2 Are longitudinal culvert ends in compliance with B-CS Standard Specifications? (!) x Yes No, then explain: '-<( .0 rJ) At intersections or otherwise, do valley gutters cross arteria l or collector streets? ::; ('· (!) 0 -u >-No __ Yes If yes explain: _c (!) I ~ rJ) ·-::J :;;: '- <fl (!) Are valley gutters proposed to cross any street away from an intersection? Q) ~ 0 ~ oi z --No __ Yes Expl ain: (num ber of locations?) ~ -u I ~ex .._ m <( Part 4 -Drainage Concept and Design Parameters I Continued (Page 4.4) Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, or Site) (continued) '-~ ::J Gutter line slopes: Least 0.005fUft Usual 0.005ft/ft Greatest 0.011fVft Ol -u C'· c -u m w .0 rJ) ::; ::J Are inlets recessed on arterial and coll ector streets? Yes _x_ 0 identi fy where and why. £ ~ Not Applicable. STORMWATER DESIGN GUIDELINES Effective February 2007 Page 12 of 26 -- APPENDIX D: TECH. DESIGN SUMMARY As Revised February 2008 No If "no", SECTION IX APPENDIX D -TECHNICAL DESIGN SUMMARY Will inlets capture 10-year design storm flow to prevent flooding of intersections (arterial with arterial or collector)? __ Yes _X __ No If no, explain where and why not. Not Applicable. Will inlet size and placement prevent exceeding allowable water spread for 10-year design storm throughout site (or phase)? --Yes _X_ No If no, explain. Not Applicable. Sag curves Are inlets placed at low points? --Yes x No Are inlets and conduit sized to prevent 100-year stormflow from ponding at greater than 24 inches? --Yes _X __ No Explain "no" answers. Not Applicable. Wil l 100-yr stormflow be contained in combination of ROW and buried conduit on whole length of all streets? --Yes _X __ No If no, describe where and why. Not Applicable Do designs for curb, gutte r, and inlets comply with 8-CS Technical Specifications? Yes --No If not, describe difference(s) and attach justification. Not Applicable Are any 12-inch laterals used? _x_ No --Yes Identify length(s) and where used . ('· Pipe runs between system access Typical BO ft Longest 96.4ft -0 Q) en en Q) points (feet): ::J >-E xl 2 Are junction boxes used at each bend? _x_ Yes No If not, explain en -->-where and why. en c ~ 0 -0 z E I .9 Are downstream soffi ts at or below upstream soffits? Least amount th at en .!!2 Ye s x No __ If not, explain where and why: hydraulic grade line is below gutter line (system- wide): 0.42 fe et Part 4 -Drainage Concept and Design Parameters I Continued (Page 4.5) Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, or Site) (continued) Q) Q) '--Describe watercourse(s), or system(s) receiving system discharge(s) below (inclu de ~ -0 0 design discharge velocity, and angle between converging flow lin es ). ro ·-'+--.__ > o en (\) 0 '+-::::-o. Q_ .S ro 1) Watercourse (or system ), velocity, and angle? Q) '+-enQ) UJ:) Detention pond outfall structure to Rock Prairie Road drainage ditch, 3. 20fps from 24" c aJ E O 0 _c (\) RCP in 100 year design storm, 70°34 '35" en en STORMWATER OESIGN GUIDELINES Effective February 2007 Page 13 of 26 APPENDIX D: TECH. DESIGN SUMMARY As Revised February 2008 SECTION IX APPENDIX D -TECHNICAL DESIGN SUMMARY 2) Watercourse (or sys tem}, velocity, and angle? Detention pond outfall structure to Rock Prairie Road drainage ditch, 3. 01 fps from 4.25ft long sharp-crested weir in 100 year de sign storm, 70°34'35" 3) Watercourse (or sys tem), velocity, and angle? Two 18" RCP culverts under driveway along Rock Prairie Road drainage ditch, 5. 58fps in 2 5 year design storm, parallel with flow For each outfall above, what measures are taken to prevent erosion or scour of receiving and all facilities at junctu re? 1) Install established sod. 2) Install established sod. 3) Install established sod. Are swale(s) situated along property lines between properti es? _x_ No Yes -- Number of instances: For each instance answer the following questions. Surface treatments (including low-flow flumes if any): C'-· (/) (i) CJ) .;:; (/) Flow line slopes (minimum and maximum) (/) CJ) c >- ro I .__ u .9 u CJ) 0 (/)z ixl Outfall characteristics for each (velocity, convergent angle, & end treatment). (/) CJ) ~ Will 100-year design storm run off be contained within easement(s) or platted drainage ROW in all instances? __ Yes __ No If "no" explain Part 4 -Drainage Concept and Design Parameters I Continued (Page 4.6) Stormwater Management Concept (continued) W ithin Or Serving Subject Property (Phase , or Site) (continued) CJ) Are roadside ditches used? --No _X __ Yes If so, provide the following u (/) Is 25-year flow contained with 6 inches of freeboard throughout ? _X_ Yes ·-CJ) (/) _c u 0 Are top of banks separated from road shoulders 2 feet or more? _x_ Yes ro ~ 0(5 Are all ditch sections trapezoidal and at least 1.5 feet deep? x Yes 0::: STORMWATER DESIGN GUIDELINES Effective February 2007 Page 14 of 26 APPENDIX D: TECH. DESIGN SUMMARY As Revised February 2008 -- -- -- No No No SECTION IX APPENDIX D -TECHNICAL DESIGN SUMMARY For any "no" answers provide location(s) and explain If conduit is beneath a swale, provide th e following information (each instance). Instance 1 Describe general location, approximate length: Cf) Q) >- I ~ Is 100-year design flow contained in conduit/swale combination? __ Yes Cf) Q) --u No If "no" explain: c: 0 ~ z Cf) xi c: Space for 100-year storm flow? ROW Easement Width -m Swale Surface type, minimum and Conduit Type and size, minimum and c: 0 ·.;::; maximum slopes: maximum slopes, design storm: ('· u Cf) u Qj m c: >-c: m c: Inlets Describe how conduit is loaded (from streets/storm drains, inlets by type) _c m u 0 c: '+- Q) c: o_ 0 0 :;::; Access Describe how maintenance access is provided (to swale, into conduit) '+-m 0 E :J 0 Q) '+--c: c: ·- Q) u E Instance 2 Describe general location, approximate length : Q) m Cf) Cf) :J Cf) Q) c: :2 0 > Is 100-year design flow contained in conduit/swale combination? __ Yes ro 2 --c: o_ No If "no" explain : i5 Q) E Q) 0 _c u Cf) Space for 100-year storm flow? ROW Easement Width ~ 2 :J m Swale Surface type, minimum and Conduit Type and size, min imum and u '--c: m maximum slopes: maximum slopes, design storm : 0 o_ u Q) Cf) Q3 c: Inlets Describe how conduit is loaded (from streets/storm drains, inl ets by type) m 0 3 ~ Cf) Q) <'.i: Access Describe how maintenance access is provided (to swale, into conduit) Part 4 -Drainage Concept and Design Parameters I Continued (Page 4.7) Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, or Site) (continued) u Cf) Q) 0 Cf) If "yes" provide the following information for each instance .!!:? .§ -== z ~ In stance 1 m .o :J 3~u C/l:;c:x -0 0 = _c u s :'='. 3 STORMWATER DESIGN GUIDELINES Effective February 2007 Describ e general location, approximate length, surfacing: Page 15 of 26 APPENDIX D: TECH. DESIGN SUMMARY As Revised February 2008 SECTION IX APPENDIX D -TECHNI CAL DES IGN SUMMARY 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 in stance. "New" channels: Will any area(s) of concentrated flow be channelized (deepened , C'· widened , or straightened) or otherwise altered? No Yes If on ly slightly u c ----~~ shaped, see "Swales" in this Part If creating sid e banks, provide information below. 0 0.. 0.. x Will design replicate natural channel? Yes No If "no", for each e w ---- 0.. instance describe section shape & area, flow line slope (min. & max.), surfaces, en en and 100-year design flow, and amount of free boa rd : ~ Q) c >-I I Instance 1: 0.. E o ·-z Instance 2: 1 xi Instance 3: u Part 4 -Drainage Concept and Design Parameters j Continued (Page 4.8) Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, or Site) (co ntinued) Existing channels (small creeks): Are these used? _x_ No --Yes If en c:~ "yes" provide the information below. Q) Q) u Will small creeks and th eir floodplains remain undisturbed ? _lli6_ Yes c E ~ --c Q) c How many disturbance instances? Identify each planned location ro >~ ..c 0 c u ...._ 0 0.. u E-- STO RMWATER DESIGN GUIDELINES Effective February 2007 Page 16 of 26 APPENDIX D: TECH. DESIGN SUMMARY As Revised February 2008 No SECTION IX APP END IX D -TE CHNI CAL DESIGN SUMMARY For each location, describ e length and general type of proposed improvement (including floodplain changes): For each location, describ e section shape & area, flow line slope (min. & max.), surfaces, and 100-year design flow. W atercourses (and tributaries): Aside from fringe changes, are Regulatory Watercourses proposed to be altered? _X __ No __ Yes Explain below. Submit full report describing proposed changes to Regulatory Watercourses Address existing and proposed section size and shape , surfaces, alignment, fl ow line changes, length affected, and capacity, and provide full documentation of analysis procedures and data. Is fu ll report submitted? Yes --No 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. Will 100-year flow be contained with one foot of freeboard? --Yes --No If not, identify location and explain: Are ROW I easements sized to contain channel and required maintenance space? --Yes --No If not , identify location(s) and explain: Part 4 -Drainage Concept and Design Parameters I Continued (Page 4.9) Stormwater Management Concept (continued) Within Or Serving Subject Property {Phase, or Site) (continued) c:--. 0 How many facilities for subject property project? 1 For each provide info. uz below. c Q) I 0 C/) For each dry-type facility Facility 1 Facility 2 ·-0 ~ 0. c 0 Acres served & design volum e + 10% Q) '-4.3ac 0.80 ac-ft Q) Q_ C/) 0 C/) Q) 100-yr volume: free flow & plugged 0.72 ac-ft 0.85 ac-ft m.~rl ~ '= Design discharge (10 yr & 25 yr) 11.8 cfs 14.8 cfs gx LL Spillway crest at 100-yr WSE? _lL yes --no _yes -- Berms 6 inches above plu gged WSE? _X_ yes no __ yes STORMWATER DESIGN GUIDELINES Effective February 2007 Page 17 of 26 APPENDIX D: TECH . DESIGN SUMMARY As Revised February 2008 no no SECTION IX APPENDIX D -TECHNICAL DESIGN SU MMARY Explain any "no" answers: For each facility what is 25-yr design 0 , and design of outlet structure? Facility 1: The 25-yr design flow is 14.8 cfs. The outlet structure has a 1. 23 sq. ft orifice inlet opening, with an invert elevation of 269.30 a 24 " RCP, and a 4.25ft long sharp-crested weir at an elevation of 271. 36. Faci lity 2 Do outlets and spillways discharge into a public facility in easement or ROW? Facility 1: _X_ Yes --No Facility 2 --Yes --No If "no " explain : For each, what is velocity of 25-yr design discharge at outlet? & at spillway? Facility 1: 2.79fQS & 2.32fQS Facility 2: & Are energy dissipation measures used? _x_ No --Yes Describe type and location: For each, is spi llway surface treatment other th an concrete? Yes or no, and descri be: Facility 1: Yes, the spillway is a 4.25ft long concrete sharp-crested weir, with a 26 ft long concrete sharp-crested weir emergency spillway. The surface treatment will be established sod. Facility 2: For each, what measures are taken to prevent erosion or scour at receiving facility? Facility 1: Installation of established sod on detention pond side slopes and spillway Facility 2: If berms are used give heights, slopes and surface treatments of sid es. Facility 1: Facility 2: Part 4 -Drainage Concept and Design Parameters I Continued (Page 4.10) Stormwater Management Concept (continued) Within Or Serving Subject Property (Ph ase, or Site) (continued) ~ Do structures comply with B-CS Specifications? _x_ Yes or _no, and explain if "no": u QJ ::J Facility 1: c -~ o~ ·-c ~ 0 c u QJ -~ (/) Facility 2: QJ QJ 0:;::; -u cu LL For additional facilities provide all same information on a separate sheet. STORMWATER DESIGN GUIDELINES Effective February 2007 Page 18 of 26 APPENDIX D: TECH. DESIGN SUMMARY As Revised February 2008 SECTION IX APP ENDIX D -TECHNI CAL DES IGN SU MMARY Are parking areas to be used for detention? x No --Yes What is maximum depth due to required design storm? Roadside Ditches : Will culverts serve access driveways at roadside ditches? --No _x_ Yes If "yes", provide information in next two boxes. Will 25-yr flow pass without flowing over driveway in all cases? x Yes --No Without causing flowing or standing water on public roadway? x Yes --No Designs & materials comply with B-CS Technical Specifications? x Yes --No Explain any "no" answers ('-· Cf) Ol c Cf) Are culverts parallel to public roadway alignment? _x_ Yes No Explain: Cf) --0 ,__ Cf) () (j) 2 >-.~ I o._x Creeks at Private Drives: Do private driveways, drives, or streets cross drainage co ways that serve Above-Project areas or are in public easements/ ROW? __ X_ No -0 0 Yes If "yes" provide information below. (j) z -- Cf) I :::i How many instances? Describe loca tion and provide information be low. 2 Location 1: Qi -2: :::i () (j) Location 2: ~ Location 3: For each location enter value for: 1 2 3 Design yea r passing without toping travelway? Water depth on travelway at 25-year fl ow? Water depth on travelway at 100-year fl ow? For more instances describe location and same information on separate sheet. Part 4 -Drainage Concept and Design Parameters I Continu ed (Page 4.11 ) Stormwater Management Concept (continued) Within Or Serving Subject Property (Ph ase, or Site) (continued) () Named Regulatory Watercourses (&Tributaries): Are culverts proposed on the se Cf)= facilities? _x_ No __ Yes, then provide full report documenting assumptions, t .D ~ (j) :::i co criteria, analysis, computer programs, and study findings that support proposed -2: Q_ ~ :::i ~ -0 design(s). Is report provided? __ Yes No If "no", explain () co co -- (j) -0 0 ,__ (j) ,__ <( Cf) :::i STORMWATER DESIGN GUIDELINES Effective February 2007 Page 19 of 26 APPENDIX D: TECH . DESIG N SUMMARY As Revised February 2008 SECTION IX APPENDIX D -TECHNICAL DESIGN SUMMARY Arterial or Major Collector Streets: Will culverts serve these types of roadways? _x_ No --Yes How many instances? For each identify the location and provide th e.information below. Instance 1: Instance 2: In stance 3: Yes or No for the 100-year design flow 1 2 3 Headwater WSE 1 foot below lowest curb top? Spread of headwater wi thin ROW or easement? Is velocity limited per cond itions (Table C-11 )? Explain any "no" an swer(s) Minor Collector or Local Streets: W ill culverts serve these types of streets? _x_ No __ Yes How many instances? for each identify the location and provide the information below Instance 1: Instance 2: Instance 3: For each instance enter value, or "yes" I "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 cond itions (Table C-11 )? Limit of downstream analysis (feet)? Explain any "no" an swers: Part 4 -Drainage Concept and Design Parameters I Continued (Page 4.12 ) Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, or Site) (continued) All Proposed Culverts: For all proposed culvert facilities (except driveway/roadside ~ ditch intersects) provide information requested in next eight boxes. (/) "D ~Cl) '-:J Do culverts and travelways intersect at 90 degrees? Yes No Cl) c ----..2::.;::; identify location(s) and intersect angle(s), and justify the design(s): :J c u 0 0 STORMWATER DESIGN GUIDELINES Effective February 2007 Page 20 of 26 APPENDIX D: TECH. DESIGN SUMMARY As Revised Februar 2008 If not, SECTION IX APPE NDIX D -TECHNICAL DESIGN SUMMARY Does drainage way alignment change within or near limits of cu lvert and surfaced approaches thereto? __ No __ Yes If "yes" identify location(s), describe change(s), and justification: Are flumes or conduit to discharge into culvert barrel(s)? id entify location(s) and provide justification No __ Yes If yes , Are flumes or conduit to discharge into or near surfaced approaches to culvert ends? __ No __ Yes If "yes" id entify location(s), describe 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 in street ROW, and/or drainage easements/ ROW? __ Yes __ No if not, why not? Do appreciable hydraulic effects of any culvert extend downstream or upstream to neighboring land(s) not encompassed in subject property? __ No __ Yes If "yes " describe location(s) and mitigation measures: Are all culvert designs and materials in compliance with B-CS Tech. Specifications? __ Yes __ No If not, explain in Special Design Section of th is Part. Part 4 -Drainage Concept and Design Parameters I Continued (Page 4.13) Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, or Site) (continued) Is a bridge included in plans for subject property project? _X_ No __ Yes If "yes provide the foll owing information. ~ Name(s) and functional classification of the roadway(s)? !fl Q) Ol u '--0) What drainage way(s) is to be crossed? STORMWATER DESIGN GUIDELINES Effective February 2007 Page 21 of 26 APPENDIX D: TECH. DESIGN SUMMARY As Revised February 2008 " SECTION IX APPE NDIX D -TECH NICAL DESI GN SUM MARY A full report supporting all aspects of the proposed bridge(s) (structural, geotechnical, hydrologic, and hydraulic factors) must accompany this su mmary report. Is the report provided? --Yes --No If "no" explain Is a Stormwater Provide a general description of planned techniques: .?: Pollution Prevention -Plan (SW3P) Tot al disturbed area will be less than 5. 0 acre s (lj ::J a establi shed for Storm water pollution control measures during construction ~ project construction? will include silt fence, rock check dams, construction (lj x No Yes entrances, and other best management practice s as required. s -- Special Designs -Non-Traditional Methods Are any non-traditional methods (aquatic echosystems, wetland-type detention, natural str eam replication, BMPs for water quality, etc.) proposed for any aspect of subject property project? x No --Yes If "yes " list general type and loca tion below. Provide full report about th e proposed special design(s) including rationale for use and expected benefits. Report must substantiate that storm water management objectives will not be compromised, and that maintenance cost will not exceed those of traditional design solution(s) Is report provided? --Yes --No If "no" explain: Not Applicable. Part 4 -Drainage Concept and Design Parameters I 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 materi al(s) of traditional ru noff-handling facilities deviate fr om provisions of 8-CS Technical Specifications, check type facility(ies) and explain by specific detail element. --Detention elements __ Drain system elements --Channel features Culve rt 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 STORMWATER DESIGN GUIDELINES Effective February 2007 I Ju stification for Deviation (attach additional sheets if needed) Page 22 of 26 APPENDIX D: TECH. DESIGN SUMMARY As Revised February 2008 SECTION IX APPENDIX D -TECHNICAL DESIGN SUM MARY 1) 2) 3) 4) 5) Have elements been coord inated 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 Is a map(s) showing all Design Drainage Areas provided? x Yes --No Briefly summarize the range of applications made of the Rational Formula: Utilized for all on-site drainage areas, intensities and "C" factors per Bryan/College Station design guidelines with a minimum time of concentration of 10 minutes. What is the size and location of largest Design Drainage Area to which the Rational Formula has been applied? 1.18 acre s Location (or identifier) Part 4 -Drainage Concept and Design Parameters I Continued (Page 4.15) Design Parameters (continued} Hydrology (continued) In making determinations for time of concentration, was segment analysis used?~ No Yes In approximately what percent of Design Drainage Areas? % As to intensity-duration-frequency and rain depth criteria for determining runoff fl ows, were any criteria other than those provided in these Guidelines used? _X __ No --Yes identify type of data, source(s), and where applied: STORMWATER DES IGN GUIDELINES Effective February 2007 Page 23 of 26 APPE NDIX D: TECH. DESIGN SUMMARY As Revised February 2008 If "yes" SECTION IX APPEND IX D -T ECHNICAL DESIGN S UMMARY For each of the storm water management features listed below identify the storm return frequencies (year) analyzed (or checked), and th at used as th e basis for design. Feature Analysis Yea r(s) Design Year Storm drain system for arterial and collector streets Storm drain system fo r local streets Open channels Swale/buried conduit combination in lieu of channel Swales Roadside ditches and culverts serving them Detention facilities: sp illway crest and its outfall 2, 10, 25 , 50 , 100 100 Detention facil ities: ou tlet and conveyance structure(s) 2,10, 25, 50, 100 100 Detention facil ities: volume when ou tl et plugged 2, 10, 25 , 50, 100 100 Cu lverts serving private drives or streets 2, 10, 25 25 Cul verts serving public roadways Bridges: provide in bridge report. Hydraulics What is the range of design flow velocities as outlined below? Des ign flow velocities; Gutters Conduit Culverts Swales Channels Hi ghest (feet per second) 4.14 cfs 5.58 cfs Lowest (feet per second) 3.04 cfs 5.58 cfs Streets and Storm Drai n Systems Provide th e summary informati on outlined below: Roughness coefficients used : For street gutters: For conduit type(s) RCP Coefficients: 0.013 Part 4 -Drainage Concept and Design Parameters I Continu ed (Page 4.16) Des ign Parameters (contin ued) Hydraulics (continued) Street and Storm Drain Systems (continued) For the following, are assumptions other than allowable per Guidelines? Inlet coefficients? _x_ No --Yes Head and friction losses _x_ No --Yes Explain any "yes" answer: In conduit is velocity generally increased in the downstream direction? --Yes _x_ Are elevation drops provided at inlets, manholes, and junction boxes? x Yes --Explain any "no" answers: The velocity in the in the storm sewer pipe sections do not increase; they are equal because their flows and diameters remain constant. STORMWATER DESIGN GUIDELINES Effective February 2007 Page 24 of 26 APPENDIX D: TECH. DESIGN SUMMARY As Revised February 2008 No No SECTION IX APPEND IX D -TECH NICAL DESIGN SUMMARY Are hyd rauli c grade lines calcu lated and shown for design storm? _x_ Yes --No For 100-year flow cond iti ons? _X_ Yes __ No Explain any "no" answers: What tailwater condi tions were assumed at outfall point(s) of the storm drain system? Identify each location and explain: In the location where the detention pond discharges into the Rock Prairie Road drainage ditch, it is assumed that negligible tailwater conditions exist. Open Channels If a HEC analysis is utilized, does it follow Sec Vl.F.5.a? --Yes --No Outside of straight sections, is flow regime within limits of sub-critical flow? --Yes --No If "no" list locations and expl ain Culverts If pl an 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? Entrance, fri ction and exit losses: Bridges Provide all in bridge report Part 4 -Drainage Concept and Design Parameters J Co ntinued (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 faci lity designs proposed for subject property project? List them below, being sure to identify the software name and version, the date of the version , any applicable patches and the publisher HEC-HMS; Version 3.2; April 21 , 2008; U.S. Army Corps of Engineers Office Excel® 2007, (12.0.6214.1000) SP1 MSO (12.0.6213.1000); ©2006 Microsoft Corporation Part 5 -Plans and Specifications STORMWATER DESIGN GUIDELINES Effective February 2007 Page 25 of 26 APPENDIX D: TECH. DESIGN SUMMARY As Revised February 2008 SECTION IX APPENDIX D -TECHNICAL DESIGN SUMMARY Requirements for submittal of construction drawings and specifications do not differ due to use of a Technical Design Summary Report. See Section Ill, Paragraph C3. Part 6 -Conclusions and Attestation Conclusions Add any concluding information here Attestation Provide attestation to the accuracy and completeness of the foregoing 6 Parts of thi s Technical Design Summary Drainage Report by signing and sealing below. "This report (plan) for the drainage design of the development named in Part B was prepared by me (or under my supervision) in accordance with provisions of the Bryan/College Station Unified Drainage Design Guidelines for th e owners of the property. All licenses and permits required by any and all state and federal regulatory agencies for the proposed drainage improvements have been is sued or fall under applicable general permits." State of Texas PE No._,f,___,tfis'7~_,__ __ _ STORMWATER DESIGN GUIDELINES Effective February 2007 Page 26 of 26 APPENDIX D: TECH. DESIGN SUMMARY As Revised February 2008