The URL can be used to link to this page

Home My WebLink AboutPD 2019-0009; 2700 ARGONAUTA RESIDENCE; LIMITED DRAINAGE STUDY; 2019-07-02C I 154.6.005" Prepared By: mENGINEERING' vx 2121 Montiel Road, San Marcos, CA 92069 DESIGN GROUP 760.839.7302 / www.designgroupca.com LIMITED DRAINAGE STUDY RECORD Copy Erin Rist RCE 65122 RECEIVED JUL 02 2019 LAND DEVELOPMENT ENGINEERING ---------- Initial Date - PROJECT DESCRIPTION The subject property is described as APN 215-460-05 and is located at Argonauta Street near the intersection with Obelisco Circle, Carlsbad, California. The property is approximately 0.75 acres and is currently undeveloped. Portions of the lot were previously graded. In general, the property slopes, descending from the south (front) to the north (rear). PROJECT SCOPE The proposed new scope of work consists of the construction of a new multi-level single family residence and associated driveways and landscape elements. BASIN DESCRIPTION AND FLOW PATTERNS The subject site has been divided into two primary Basins, as more specifically described below. Basin Hi: Basin Hi includes the area of proposed development. Basin H2: Basin H2 Includes existing unimproved sloped areas that will remain in the existing condition post development. Pre-development flow consists of sheet flow across the undeveloped site. An existing concrete brow ditch runs along a 10 ft. wide drainage easement, from east to west, along the north property line. Sheet flow runoff is captured by the existing brow ditch. In the post development condition runoff will be directed from roof downspouts to landscape areas, where possible, and new catch basin inlets. New private storm drain system will direct water to a new onsite retention basin for containment of increased flows as part of onsite development. Detention basin was sized utilizing a reservoir storage method, wherein the increase in volume of runoff due to development is calculated and compared to predevelopment flows. Increased volume is contained, and outflows are designed to be similar to pre-development condition. In this case pre-development runoff flows as sheet flow. Retention basin overflow outfall will be by pipe to a gravel subsurface disbursement trench, so as not to concentrate runoff, create similar sheet flow condition. Sizing of retention area is included in the attached hydrology and hydraulic calculations. WEBSTER RESIDENCE Argonauta Street, Carlsbad PRELIMINARY HYDROLOGY CALCULATIONS C(composite) I C=0.90 x % impervious surfaces + Cp x (1-%lmpervlous) RATIONAL METHOD FOR TRIBUTARY c 0.5 SQ MILE Q= CIA I (in/hr) - 100 YR 7.40 =7.44 P6 DA(0.645) P6 2.8 I (inlhr) - 50 YR 6.59 =7.44 P6 DA(0.645) P6 2.50 SOIL TYPE D HYDROLOGIC & HYDRAULIC DESIGN BASIN NO. TOTAL AREA TOTAL AREA (ac) IMPERV AREA(sf) AREA IMPERV % IMP AREA PERV AREA PERV c T Q100 (cfs) Drainage Device Elev 1 (ft) Elev 2 (ft) Length (ft) Slope (ft) Add-1 Q Device Size P650A'C PRE-DEVELOPMENT ONSITE HI 15,110 0.35 - 0.00 0.00 15,110 0.35 0.35 5 0.90 1,102 H2 17,445 0.40 - 0.00 0.00 17,445 0.40 0.35 5 1.04 32,555 TOTALQ 1.94 POST DEVELOPMENT ONSITE 1-1A 4,105 0.09 4,105 0.09 1.00 - 0.00 0.90 5 0.63 Impervious - Pipe to bioretention Pervlous - Sheetfiow 504.0 483.5 67.0 0.31 6in - 770 H1B 4,145 0.10 4,075 0.09 0.98 70 0.00 0.89 5 0.63 Downspouts divided to H1C, HID, HIA, Various 769 HIC 1,820 0.04 - 0.00 0.00 1,820 0.04 0.35 5 0.11 Roof Gutters to Landscape to Pipe 513.6 504.8 30.0 0.29 6in 133 HID 745 0.02 - 0.00 0.00 745 0.02 0.35 5 0.04 Roof Gutters to Landscape to Pipe 514.9 514.9 65.0 0.00 6in 54 HIE 1,460 0.03 - 0.00 0.00 1,460 0.03 0.35 5 0.09 Sheet flow 6 in 106 H1F 2,345 0.05 120 0.00 0.05 2,225 0.05 0.38 5 0.15 Downspoutr to Pipe 493.4 483.5 74.0 0.13 6in 185 14,620 Subtotal 1.64 2,017 delta Q 0.75 H2 18,035 0.41 - 0.00 0.00 18,035 0.41 0.35 5 1.07 Sheetfiow 8,300 TOTALQ 2.72 32,655 0.75 DETENTION VOLUME Area OS dP Area(sf) Depth (ft) Provided Hi 915 1,035 1.10 1,139 ProvidedArea - Area *Depthof Base *0.4 WO Aw c--- —: HYDROLOGY PRE- DEVELOPMENT Ir (489)' 1- 489 95) —(497) 499) '500) ('501 (502 DRAINAGE SUMMARY TABLE Basin Area (ac) Impervious Area (ac) Q (cfs) Hi 0.35 0 0.90 H2 0.40 0 1.04 PROJECT BOUNDARY HYDROLOGY SUB—BASIN FLOW DIRECTION DRAINAGE SUMMARY TABLE Basin Area (ac) Impervious Q (cfs) H1A 0.09 0.09 0.63 H1B 0.09 0.09 0.63 H1C 0.04 0 0.11 HiD 0.02 0 0.04 ME 0.03 0 0.09 H1F 0.05 0.01 0.15 H2 0.41 0 1.07 - - - - PROJECT BOUNDARY FLOW DIREC11ON HYDROLOGY BASIN PRP. BLDG SURFACE—IMPERV1OL1fS PRP CONC/AC PAVING (E) AC PAVING 4 HYDROLOGY POST-DEVELOPMENT I HYDROLOGY %0Wq%0qI9%1,q, 611111111 HIM 11111111111111111111111111111111111111111 INS 1111111111111111IIII 1111111 IIIIIIIIIIIIIIIIIIIIIIIuUlIUUIIIIIIIIIIIIII 1111111 EQUATION IIIIIIIIIIIIIIIIIlIIIIIIIIIIIIIIIIIIIIIIIII 1111111 IlIllIlIHhlIlI! ______________________________ IIIIIII 1111IIIIIIIII II 'q1iIj'II Ii'tIIhuIIIII DurationEZINII'lilli Ifi1q, illiql4lil 11111111 Jill 1111 1 Intensity (in/hr) IIIlIIIIIIIU•IIIIIHllIUhII 1fil Ill; 111.9111,111111.. IlLoillillillilillillilillill IIuIii:!uuIIIIII!!IIiIIIllI'!uIIIIIIIiII III! 1II11iIDI! ?i!! IlIlIllIHIl 1111111 IIIIIIIIIiiiiI!!!!1IliiiiI F!.IIIi ••UUUIIII•IIIIIIIIII!ItII IiiiiiiiiIui;11 1111111111101111111 111116"Mil Oki 101 h 14 11vil 11111 son uui•iiuuuuuiiuuiuii Ill ii IItIi!!II 11 Ill IIIIIi!IIIUhIIIIIti Own I!IhiIIti !IIi IIIIUIIIIIIIIlIlIIIIII ill II IIIIIIHIII!!IIIIJIIIIIIIIIII!!IIIIII!iIi 1111!!!II1 i!!ii IIIIuuIIIIIIIIlIIIIIIII Ill I IllIllIllIllIll II T IIIII III IIIIIII H IIIIIIIIIIIIIISHIMITHR1111,ill IIIIIIIIIIII Hill Mill IIIlIIIIIIIIIIHill 111111 1111111111111111111111 ill 11111111111118 111111 1111111 1UtI uIIhIIIhhI...U. I.... 111111111111111111 ... U...... S••UU•UUIUUUI IllIltUull U•••U IUIUUUtIUIluuIuuIUIuIII ••h'UIUUuIIII U,.,,, — ------ -- — -- ____. C.... Iflflt lint Stills UNUUUII flU lllliiluitililllt l CC •Ub UifllI 1111111 ---------IIIIIIIIIIIICUNU .....511551111115111 uluiiiltlu....1,::: U.UIIII,151111151U1 1111,11,1111150501 ill iiuuuuutuuuI •••••U•*uuiiiiI,.uuiufl u,flhlulul...I uuIIIuuIuuhuuuIIuuIuI •uuuu ...uIIIIuIluuuII ________u.u..0 MEN sell ,Ii u,mu,IIuI.i.i .uiii,uuuiiuuuuiiiu,iIi ..u. ...uiuuiiui .iI: uuliilllillul.I sill. .ulu,IIIuuIuIulIul ...uu ...uui,u,uui hull .•......u.uuu..uuu,iiiiuuiuuiu.uuuiuiuiiiiuuiiiluuuuiulli INN •u NOUN uuuuumuisuiuiiuur ••••uu•ui•uuuuuuiuuii i,iuiuiniiuuui ,iuuiuuiiiuuuuuiuuiii INN ...... ..iu.•.•u.•• 1111111 ••••• ••• •• iuiuui liii IllIl1 1,111111111111111111 IllIlUhIll uuuuiiuuiii.. UUUU• UUUIiI UuuIuIluIlIll •••••UUUU•UIUIIiIUiHiIIII IlIllIlIHUHhl 11111 iIIlIiIIlIIiiIIIIIUUiiII 111111 HIM 1111111 ...........u.uiuu.uiuuuuii iiiiiiiiiiiiiii 11111 iiiiiiiiiiiiiiiiii.....u.. uuiniiiuuii 1111111 ••••••UUUUilllliiiiliiiiiilllilllllHiiili IIlIIIIIIIIIIIIIIIIIIlIIIUIIIIllIlIIHhIIII 1111111 I 1 I 1''I i I Imperial County . ........ . .......... ....... ..... ____ I - 1 0 k p. ...•' ,•':..--,"r' . .. ' . ( :'.: .:::::::::-. ...•. - .• . ii ...'...... i ..?i. MLLI .i•j 08 d 4,' Lon I I 4_ O o - Z + Imperial County - 1 . ¶ / ' t V ...:: . w/ .. U ( - - ad 4 V ce ) . -'H •- p LIJ A i/I 1601bIbR, all 1111111111 HIH IIIIIIIIIIIIIlHIIIIllhUI U milli IIIuIIHIM 1111111 1111111111111111111111111111111111111111111111111111111111 mIIIIIIIIIIIIIIII 1111111 ONE! kilk! 11IRS20 Q191 111111111111111111111111111111111111111111111 HIM on 111111IIIIIlJIIIIIl IllIllIllIllIll 11111111111 _______________________________ 11111111 1111111! ratioDu Ps 0 IIIIIIIII!IIIuuIIIIIIIIIIIIIIII UIII1!III!IIIi!IIIi!lI II'fli!I !;:;:'IIIIIIIIuIIIIIu iiiioiuuiiiiiii IIIIii!iIIIIIII!!IIIiiill!'!llhiiifl i!!!IIIIIIIIIII 1111111 IIIIIIIIIiiIi1O!!IIIIIlii •••••uuuu•uuiiuiuuii:!iiti iiiiiiiiiiui;i IIIIIlIIIi;'IIIIJIIiiIu !!l Monson l Nonni IIIIuIIIIlIh!IIIIIIIII 11111101111111111116:911 111 UlIul1!Ii1IIi :!II son IUIUUIUIIUIIIII1IIIIIIIIIIri!!II 11 Ill IIIIIl!!IIIIIIIIlI!IiiOHM 01111I1111IIi1 IuuIIIIuuIuuuuuuIIIIIIIIHIIIIIIIIIIIj;!! Ill IIIIIIIIIIIII!!lJI ill !uII:IIh;!!Hh;!!j IIIIIIIIIlIIIIIIIUhIIIIIII IllIllIllIllIll lIi!!!IIllhIIlIIIIIIIII!IIII!!II1j!!II !!!!I CC IIIIIIIIIIIIIIIIIIIIIIIIIII IlIllIllIllIll 1111111111 ii!LIIllhI IiI!!IIhi!!Uhi!ll IIIIIIIIIIIIIIIIIIIIIIIIIIIHIfflhIHIIIIllhIIIIUI III liii ii!!IIIIiIIII!!!IIIIiiiII IIrs,u,IsI..u., •SSUSlflhII UIE.i1 ...U.UUUP, IISISSUISIUUI UUUUUUIIuIIIIUIIS 111111 S..Uk.UIJUUflSIISH CC CC ..U.....U,UU,il ulIulIlIll URU•I UUUIUUIIIIIIIIIIIIIIIII •••USIUUiIIlUIIIIH ..u.....uluuuul,,u u.uuiuuuu ..u., psIusIII,IIIuuIiuiIuiJi•uuuu••uuuuuuuIIIuIuii CC ...U.UUUIuIuI,II IllIlIlIll UUUUU IIIUPUIIIIIIIIIIIIIIlII MMM MM ••••éUUUUIIulU IUIII uulIuIuIul I.U.. IiuuIuuuuuuIuuuuuIIuiui .... u...uuuuuu.I .II,: ........I.IuIIuIu uuululullu UUUUIJIIII uuuuuuuu,11111i111.UUUU ...iuuuuuuii hull CC ..••uu•Il•IuuuuuuHiIIuuIIIuhIuuuiiIuhuiIiuIuiuIIIIIIIIU••muumuUuiuiiuuuHiiuIuiur •••••••UUIU•UIiIIUIHIIIIIIIIIIIIiIIIi 11111 iuuiiuuIiuuuiiflhI•••U•U u••luuuuuluI 1111111 - Ui •iuiiUuuul 11111111111 liii 111111111111111111111111H11•••UUUUU I UUIII UllIllIlIlIll ..............u....uuiiiuiiiiiiiiiiii.u.0 uuiiitiiiiiiiuiiiiiiti.. ..u.u.uuuuiuuuuiii 1111111 UU••••U••UlUllillililiiliHiillliHiliiil uiiiiiiiiiiiiiiiiiiiii..uiiiiiiiiiiuiiiiiiiiiiii ••••u••uiuuuuuiuuiuuuiuuiiiiiiiiiiiiiuuiui flhillhiilliiilllillillU• UUIIIIIUIIIIIIIIIHIIIIII 4.00 I j I JIb flJI f Imperial County L 9L :_ CLP I ------------ — MOLL AP I I....::...• 2 •••••. ------------ 9II - - I .CQ.LI - 40.11 95 .01.111 - . - - - . .01.111 .... . . •. . Uj .L1I La / 1i hi'i ii 1 0 00 ll Z+,n Impenal County - 1, " LLI --------- / r San Diego County Hydrology Manual Date: June 2003 Section: 3 Page: 6of26 Table 3-1 RUNOFF COEFFICIENTS FOR URBAN AREAS Soil Type NRCS Elements Undisturbed Natural Terrain (Natural) Low Density Residential (LDR) Low Density Residential (LDR) Medium Density Residential (MDR) Medium Density Residential (MDR) Medium Density Residential (MDR) Medium Density Residential (MDR) High Density Residential (HDR) High Density Residential (HDR) Commercial/Industrial (N. Corn) CornrnerciaUlndusthal (G. Corn) Commercial/Industrial (OP. Corn) Commercial/Industrial (Limited L) Permanent Open Space Residential, 1.0 DU/A or less Residential. 2.9 DU/A or less Residential, 4.3 DU/A or less Residential. 7.3 DU/A or less Residential, 10.9 DU/A or less Residential. 14.5 DU/A or less Residential, 24.0 DU/A or less Residential, 43.0 DU/A or less Neighborhood Commercial General Commercial Office Professional/Commercial Limited Industrial 0 0.20 0.25 10 0.27 0.32 20 0.34 0.38 .25 0.38 0.41 30 0.41 0.45 40 0.48 0.51 45 0.52 0.54 50 0.55 0.58 65 0.66 0.67 80 0.76 0.77 80 0.76 0.77 85 0.80 0.80 90 0.83 0.84 90 0.83 0.84. 0.30 0.35 0.36 0.41 0.42 0.45 0.49 0.48 0.52 0.54 0.57 0.57 0.60 0.60 0.63 0.69 0.71 0.78 0.79 0.78 0.79 0.81 0.82 0.84 0.85 0.84 0.85 0.87 The values associated with 00/a impervious may be used for direct calculation of the ninoff coefficient as described in Section 3.1.2 (representing the pervious runoff coefficient, Cp, for the soil type) or for areas that will remain undisturbed in perpetuity. Justification must be given that the area will remain natural forever (e.g.. the area is located in Cleveland National Forest). DU/A = dwelling units per acre NRCS =National Resources Conservation Service 3-6 I EQUATION E (11.9L3 O.3$S T It C -- Tc rim, e?concentration(houra) L Watercourse Distance (mte.) 4000 E = Change in elevation along effective slope line (See Figure 3.5)(teet) 3000 To Hours Minutes 2020 4 240, 3 ISO 1000 000 000 2 120 —1100 ISO 00 500\ so 400 \ 70 I 60 300 so 200 40 L s MIles Feet —30 100 4000 20 18 3000 16 os 50 14 40 2000 12 1500 ... 1500 \ 10 1400 \ 1200 5 20 1000 7 900 500 6 100 600 10 4 400 300 S California AE Division of Highways (1941) and Kfrpith (1940) N Nomograph for Determination of Time of Concentration (Tc) or Travel Time (If) for Natural Watersheds L FIGURE HYDRAULICS HYDRAULIC DESIGN PIPES Label Solve For Friction Method Roughness Coefficient Channel Slope (ft/ft) Normal Depth (in) Diameter (in) Discharge (ft3/s) Flow Area lift") Wetted Perimeter (ft) Hydraulic Radius (in) Top Width (ft) Critical Depth (ft) Percent Full (%) Critical Slope (ft/ft) Velocity (ft/s) Velocity Head (ft) Specific Energy (ft) Froude Number Maximum Discharge (ft3/s) Discharge Full (ft3/s) Slope Full (ft/ft) Flow Type HiD to 1-11C Normal Depth Manning 0.01 0.02 '0.4 6.0 0.10 0.17 1.13 0.15 0.38 0.16 82 0.00 0.6 0.01 0.42 0.16 0.11 0.1 0.00 SubCritical H1C1 to H1C2 Normal Depth Manning 0.01 0.32 0.45 6 0.44 0.19 1.25 0.15 0.3 0.34 90.1 0.01 2.36 0.09 0.54 0.53 0.44 0.41 0.00 SubCritical H1C2 to 1-11A Normal Depth Manning 0.01 0.32 0.5 6.0 0.44 0.19 1.25 0.15 0.3 0.34 90.1 0.01 2.4 0.09 0.54 0.53 0.44 0.41 0.00 SubCritical H1F1 to H1F2 Full Flow Manning 0.01 0.15 0.5 6.0 0.28 0.2 1.57 0.13 0 0.27 100 0.00 1.4 0.03 0.53 0 0.3 0.28 0.00 SubCritical H1F2 to Outfall Full Flow Manning 0.01 0.13 0.5 6.0 0.26 0.2 1.57 0.13 0 0.26 100 1 0.00 1.3 0.03 1 0.53 0 1 0.28 0.26 0.00 ISubCritical Label Solve For Friction Method Pressure at 1 (psi) Pressure at 2 (psi) Elevation at 1 (ft) Elevation at 2 (ft) Length (ft) Roughness Coefficient Diameter (in) Discharge (ft3/s) Energy Grade at 1(ft) Energy Grade at 2(ft) Hydraulic Grade at 1(ft) Hydraulic Grade at 2(ft) Flow Area (ft') Wetted Perimeter (ft) Velocity (ft/s) Velocity Head (ft) Friction Slope (%) Notes Messages SuperCritical 1-11A to Outfall - Elevation at 11 Manning 1 0 0 485.0 483.5 67.00 0.01 6 1.1 485.51 483.99 485.02 1 483.50 0.2 1 1.57 F 5.6 0.49 2.27434 SuperCritical