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Home My WebLink About20190908 Ver 1_Haywood County - B276 - Hydro Report_20190708INFORMATION TO BE SHOWN ON PLANS WS EL. Taken @ River Station 364 500 25 2971.3 Design: Discharge c.f.s. Frequency .______.__________..yr. Elev. ______________-_------,ft. Base Flood: Discharge ---- .--- 750--- ------ c.f.s. Frequency ._______100-------- yr. Elev.,,,,,,2972:4 ft- Overtopping: Discharge---- 2050--------c.f.s. Frequency ....... >500 „yr. Elev- ------- 2976.3........ ft, *OVERTOPPING WOULD OCCUR @ STA.12+25 ADDITIONAL INFORMATION AND COMPUTATIONS USGS DISCHARGES FOR HYDROLOGIC REGION 2 - LEVEL 111 RURAL BLUE RIDGE - SIR 2009-5158 ----------------------------------------------------------------------------------------------------------------------------------------- DRAINAGE AREA = ----------------------------------------------------------------------------------------------------------------------------------------- 1.4 SQ. MI. 0.736 - a 288 DA - - - =_ 370 CFS - - - 0.724 Q25= _ _ 398 (DA) = 500 CFS ------- --------- --------- ----------------------------------------------------------- - o.ne Q�e= 479 (DA) = 600 CFS 0]13 Q100= 575 (DA) = 750 CFS ----------------------------------------------------------------------------------------------------------------------------------------- 0.704 Q5m = 794 (DA) = 1000 CFS - -- - ABUTMENT SCOUR: 100yr. (NCHRP 24-20 EQUATION) ----------------------------------------------------------------- Y�y=a(YcI=aC�1(9z�q,)�1----------------- YMm, c)=1.2[3.37(23.7334.95)�I ----- ... ......... - Y Y=2.90-2.67 = 0.23 FT. s------------------------------------------------------ Y-0--=---7=67-FT,----------------------------------------------------- -Y1--= -3-3-7 --FT --------------------------------------------------------------------------------- ql = V*H = 10.37*3.37 = 34.95 SQ.FT /S - -------------------------------------------------------------- -------------- q2c = V*H = 8.27*2.87 = 23.73 SQ. FT /S dd -------------------------------------------------------------------------------------------- Yc [1 (g2Zg1) ] - (3.37(23.7334.95) ] = 2.42 FT a = 1.2 Y.=a(Yc)= 1.2 * 2.42 = 2.90 FT HISTORICAL FLOOD INFORMATION - BOB SURRETT, LOCAL RESIDENT, HAS LIVED IN THE AREA FOR 50 YEARS. BRIDGE DOES NOT TYPICALLY OVERTOP. TYPICAL HIGHEST WSE NOTICED IS ABOUT THE LEVEL OF THE BOTTOM OF BRIDGE DURING A TYPICAL STORM. THE BRIDGE OVERTOPPED IN 2004 DURING HURRICANE FRANCES. ----------------------------------- ----- -------------- DESIGN FOLLOWS SUB REGIONAL TIER GUIDELINES ----------------------..._.-...-._.. - - ----------------------------------------------------------------------- ---------- SITE DATA Drainage Area ..... -------�•4 SQ MI Source QUAD MAP CRUSO ------------------------------------------- River Basin FRENCH BROAD MOUNTAINS /REGION 2 ---------------------------- Character - -------------------------------------- - Stream Classification (Such as Trout, High Quality Water, etc.) ----,-- , WS-III, TROUT -------------- Data on Existing Structure TIMBER FLOORS ON I -BEAMS, END BENTS: TIMBER CAPS /TIMBER POST AND SILLS AT VARYING CENTERS, SINGLE SPAN @ 25'-6" Total Waterwa Opening 79 s.f. ---- ------ - Y P 9 Waterway Opening Below 100yr. WS EL. ...... 79........ s.f. Debris Potential: Low -. X---- Moderate ....... -.High.__ _ Data on Structures Up and Down Stream _________________________________________________________________________________ US: NONE (DRIVEWAYS) ---- ---- -------------------------------------------------------------------------------------------------------- ------------------------- DS; CONFLUENCE WITH EAST FORK PIGEON RIVER (0.85 MI. DS) - - - ---------------------- - -....... -------- Design Control Elev. ._.------ 2973:6 ft. (EXIST, 100-YR WSE @ RS-364) Gage Station No. „ -,NONE Max. DischargeWAc.f.s. Historical Flood Information: Period of Records ------...... - - WA,,,-,- „ __-,-, , --------- yrs. Date ........... wA--------- Frequency --- --- WA Period of Date- 2004 Elev-._2973 ft.Est. Freq..100-__yr.Source ,,,,,,_„-,--BOB SURRET_T------------- -Knowledge__50----- yrs. Period of Date --- ----- Elev ------ --- ft. Est. Freq. - -- _---yr.Source ------------------ --------------------- Knowledge ----- _------ yrs. Period of Date___ ----- Elev.....-.....ft. Est. Freq. __ ____yr.Source --------------------------------------- ----- Knowledge _.__ .-.-Yrs. Historical Scour Info. : General ---- ------- ..ft. Contraction ------- 7-- .... ft. Local ------ - ------ ft. 0.049 FIELD SURVEY 2967... Manning's n: Left O.B----- 0.05 Channel ---- 0.04 Right O.B..... 0.05 Source FIELD SURVEY Flood Study/Status _____________NOT IN A - -------------------------------- STUDY (04,032012) Floodway Established$...._WA.._..- With With Without Flood Study 100yr. Discharge --- w?`-----c.f.s. WS Elev.: wp----- ft. Floodway ______wp...... ft. DESIGN DATA Hydrological Method SIR 2009 - 5158 & USGS RURAL REGRESSION ------------------------------------------------------------------------------------------- Hydraulic Design Method ___, HEC RAS V4.1.0 /BurnettCreek11-;prj Floods Evaluated: Freq. Q Elev. Backwater Bridge Opening Velocity (yr.) (af.$) (ft.) (ft.) (f.p.S.) @ RiverStation Q10 370 2970.7 0 8.2 364 Q25 500-------- 9713 ----2--- I—----- -- � 8=�----------- ----- - ------ ------- 600 --------- ----- - -- ----- - - -------9.. ---- Q7 - ----- ------- 750 --------- 2972.4------ -----0----- --------- 9------ 0500 ........... --2973.4----.- ------- 9I------------- Waterway Opening Provided Below:Design W.S. Elev----- 69--_.s.f.,100yr W.S. Elev.._-95__-__s.f.Total__._147, s.f., Average Channel Velocity (Design) ...... .9:0--- ,f.p.s. Average Overbank Velocity (Design) ------------ :0----- f.p.s. Computed Scour : Total ,,,,_-0.23,,,,,,__ft. Contraction ..__..-.__----------- Local _______________________ ft. Is a Floodway Revision Required? ....... --__ NO ------------------------------------------- BRIDGE SURVEY & HYDRAULIC DESIGN REPORT IV N. C. DEPARTMENT OF TRANSPORTATION �J DIVISION OF HIGHWAYS HYDRAULICS UNIT 11� RALEIGH, N. C. I.D. No.SF-430276 Project 17BP'14.R-176 11+98.67 -L- ------- Pro ---------- ------- -------------- Proj. Station --------------------- ----------- County -- -_B HAYWOOD Bridge Over ______WHY ___ WORRY Bridge CREEK g 276 __LVD _ __________________ MASSIF RD a Inv. No. RD __------ --- -BURNETTE COVE On Highway.--.- (SR 1104) SR 1103 SR 1130) 9 Y - Between - - - - and . ( ------------------------------- Recommended Structure SINGLE SPAN 45',21" CORED SLABS WITH 4'0" ABUTMENT CAP -- ------------------------------------------------------------------------------------ - - - - - - - 24-10 CLEAR WIDTH Recommended Width of Roadway-....-_32'-O" OUT TO OUT BRIDGE WIDTH _ Skew ____.__-__. 60 Recommended Location is ( Up, At Down Stream from Existing Crossing ------ 24 FT_ DOWNSTREAM - ----------------------- Statewide Tier ❑ Regional Tier ❑ Sub -Regional Tier ZI Bench Mark is BM_1:_RR SPIKE 32" SET IN CHINESE CHESTNUT" @_ N637053 E 859158 STA, 10+10.77 -L- OFFSET 83 Elev. 2984.08' ft. Datum: NAVD 88 Temporary Crossing STAGED CONSTRUCTION o: V; zDesigned by: VIDYA_MOHANDAS,_PE----- -.................. 71 Assistedby: ------------ ---------- ----_--------------------- E Project Engineer : _RANA-STANSELL, PE, CFM � Reviewed by: ;;?a Date WSP 1PAIWOM 434 Fayetteville Street Suite 1500 Raleigh, NC 27601 - 919.636.4040 w .wspgroup.wm LICENSE NO. F-o891