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HomeMy WebLinkAbout00071489FLOOD INSURE STUDY - BRAZOS COUNTY, TEXAS AND INCORPORATED AREAS COMMUNITY NAME BRYAN. CITY OF COLLEGE STATION, CITY OF WIXON VALLEY, CITY OF UNINCORPORATED AREAS COMMUNITY NUMBER 480082 480083 481636 481195 REVISED: FEBRUARY 9, 2000 3 Federal EmergencyManagey ; gency~ i~ , , 4`•'-t t~ -1f ) , ns 6 ~ ~~~.7 Y~tr ! ,l~^"._F~ t i~l. ~'V{<<*.~, ,Fr„~ G,a`~ r z. u, r' 3fr Y#r"3S~s.•~ f~ir~- Y v ~ '7v ax t A h .-'g 4 s '~•4 y,.. t r r x1 .y ,r , ti 255 250 245 0 C7 Z 240 H W W U. Z zz 235 H Q W J W 230 225 220 215 0.0 i f 4 ~t$ 1 f 4 4 + 1. { + i 1 + 1 + + + + J t t1} i r I t f 4 4 + + 1 T 1 j i J 111 J 1 I i I t + . 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T ♦ } { }y i:, t . t'}} rat nail l.ty. +tt+'i + 11}- 250 to ill { W ++al ;i j t l l t f ~ L` 4 4 4 1 4 1 + + tt }yt t t + { t t - 245 + a- t + O ~ / t-4 - -4 t 4; I . 4 { t-T T t + 1 Y 1 t 'y-+--+ 1-1-i 1 I 240 j a i + y - ♦ + , . -4 t -4 4- 4 J t t.+t 4-4-14 4 i ..l t t 1 ,-Y++: y i.-+ y -}_jT_ mot' t+filt - -r-4..-4-_Y t._I i -t.-i r}a _ _ + 4_ . t + 't-? r 1- ± t-t 1 + i + ?I + - . - 235 t. I T 1 j -1 t 11 1+++ r 1 1 J a 1 i++ 1 _.i 1 ± t-+ t ♦ t t.._ i t + t t , t - 1 t + t 1 + 1 4 4 f It f + ! r t , + + + -4 +t 4 h + ? } , + 4± i + } . t t i } t t 41 1 }j #tf' 230 t i } 1{ T, } t t} t t{ t t+ r, t a, , t+ t I t J } t } v) f i~ff} i t + ; # $ Q t t{+ ,fj 4t{}1,+ t + $ } t LLJ } r 4+}} $ ittitt j} ~ {$1tI ~ + $ } i I tt t t t z t }t„t,: . t+t} I+}} itt t I ~ f t - act 22 5 - - - C + i- + ++-4 _ _4-4 + + : LLJ 100 YEAR FLOOD } V Oa + ui C04) = { + + ; ui C= t - . STREAM BED CC l i „ CROSS SECTION w m p J 41 1 1 : 4 LOCATION Z Oct ti{1 + ++++t{ w 1 0 3 .5 4 .0 4 .5 5 .0 5.5 6.0 6 .5 )VE CONFLUENCE WI TH ALUM CREEK 45P 280 27E f~ Q Z 271 W W U. Z Z 2E O H Q W J W 6.5 7.0 STREAM DISTANCE IN THOUSANDS OF FEET A TABLE 3 - SUMMARY OF ROUGHNESS COEFFICIENTS STREAM OVERBANK "n" CHANNEL "n" Wickson Creek 0.060 - 0.085 0.050 - 0.075 Little Wickson Creek 0.060 - 0.085 0.050 - 0.065 Mathis Creek 0.060 - 0.085 0.050 - 0.065 Carters Creek 0.035 - 0.095 0.014 - 0.065 Bee Creek 0.050 - 0.095 0.035 - 0.065 Bee Creek Tributary A 0.050 - 0.085 0.040 - 0.065 Bee Creek Tributary B 0.050 - 0.095 0.040 - 0.065 Wolf Pen Creek 0.050 - 0.085 0.040 - 0.065 Wolf Pen Creek Tributary A 0.060 - 0.090 0.014 - 0.065 Wolf Pen Creek Tributary B 0.060 - 0.090 0.014 - 0.065 Wolf Pen Creek Tributary C 0.060 - 0.090 0.014 - 0.065 Hudson Creek 0.060 - 0.090 0.014 - 0.065 Burton Creek 0.014 - 0.090 0.014 - 0.080 Burton Creek Tributary C 0.060 - 0.090 0.014 - 0.065 Burton Creek Tributary D 0.015 - 0.090 0.014 - 0.090 Briar Creek 0.060 - 0.090 0.041 - 0.065 Carters Creek Tributary B 0.060 - 0.090 0.041 - 0.065 Lick Creek 0.060 - 0.090 0.050 - 0.070 Alum Creek 0.085 0.060 'Stream AC-1 0.065 - 0.085 0.050 - 0.055 Cottonwood Branch 0.060 - 0.090 0.014 - 0.065 South Fork of Cottonwood Branch 0.060 - 0.090 0.014 - 0.065 Still Creek 0.060 - 0.090 0.014 - 0.065 Still Creek Tributary A 0.060 - 0.090 0.014 - 0.065 West Fork Still Creek 0.060 - 0.090 0.014 - 0.065 Turkey Creek 0.060 - 0.090 0.014 - 0.065 Thompsons Creek 0.060 - 0.090 0.014 - 0.065 Thompsons Branch 0.060 - 0.090 0.014 - 0.065 Foxfire Creek 0.080 - 0.090 0.065 - 0.075 Spring Creek 0.040 - 0.100 0.015 - 0.060 For this countywide Flood Insurance Study, locations of selected cross sections used in the hydraulic analyses are shown on the Flood Profiles (Exhibit 1). For stream segments for which a floodway was computed (Section 4.2), selected cross section locations are also shown on the Flood Insurance Rate Map (Exhibit 2). Flood Profiles were drawn showing computed water-surface elevations for floods of the selected recurrence intervals. The hydraulic analyses for this study were based on unobstructed flow. The flood elevations shown on the profiles are thus considered valid only if hydraulic structures remain unobstructed, operate properly, and do no not fail. 19 TABLE 2 - SUMMARY OF DISCHARGES - continued FLOODING SOURCE DRAINAGE AREA PEAK DISCHARGES (cfs) AND LOCATION (sq. miles) 10-YEAR 50-YEAR 100-YEAR 500-YEAR ALUM CREEK At confluence with 1 Lick Creek 4.40 * * 4,500 At confluence of Stream AC-1 4.00 * * 5,300 Approximately 500 feet upstream of Stream AC-1 3.08 * * 4,000 Approximately 1.25 { miles downstream of State Route 6 2.61 * * 3,700 Approximately 2,000 feet upstream of State Route 6 1.84 * * 3,600 STREAM AC-1 At' confluence with Alum Creek 0.92 * * 1,750 Approximately 1.21 miles upstream of the con- fluence with Alum Creek 0.54 * * 1,350 Approximately 1.81 miles upstream of the con- fluence with Alum Creek 0.27 * * 850 COTTONWOOD BRANCH At confluence with Still Creek 6.58 3,700 5,500 6,300 8,300 Below confluence of South Fork of Cottonwood Branch 6.41 3,300 4,900 5,600 7,500 Above confluence of South Fork of Cottonwood Branch 3.86 2,200 3,260 3,700 4,900 At FM 2818 2.47 2,200 3,260 3,700 4,900 At Palasota Drive 0.56 980 1,340 1,500 1,900 SOUTH FORK OF COTTONWOOD BRANCH At confluence with Cottonwood Branch 2.55 1,300 1,930 2,200 2,950 At a point approximately 3.2 miles upstream of confluence with Cottonwood Branch 0.85 660 940 1,060 1,370 1Downstream discharge decrease is due to flatter weighted stream slopes and longer stream lengths, resulting in longer unit hydrograph times to peaks * and lower discharges. Data not computed 15 7.0 OTHER STUDIES The COE completed two studies of the area in December 1973 and December 1975, entitled Flood Plain Information, Carters Creek and Tributaries, Bryan and College Station, Texas, and Flood Plain Information, Thompsons Creek and Tributaries, Bryan, Texas (References 6 and 1). These reports investigated the flooding potential on portions of Carters Creek, Bee Creek, Wolf Pen Creek, Burton Creek, Briar Creek, Thompsons Creek, Thompsons Branch, Still Creek, West Fork Still Creek, Cottonwood Branch, and South Fork of Cottonwood Branch. Flood Insurance Studies have been prepared for the unincorporated areas of Madison, Grimes, and Burleson Counties (References 25, 26, and 27). Because it is based on more up-to-date and detailed analyses, this study supersedes the Flood Hazard Boundary Map for the unincorporated areas of Brazos County; and the previously printed Flood Insurance Studies for the Cities of Bryan and College Station (References 24, 22, and 23). 8.0 LOCATION OF DATA Information concerning the pertinent data used in the preparation of this study can be obtained by contacting FEMA, Mitigation Division, Federal Regional Center, Room 206, 800 North Loop, Denton, Texas 76201- 3698. 9.0 BIBLIOGRAPHY AND REFERENCES 1. U. S. Army Corps of Engineers, Fort Worth District, Flood Plain Information, Thompsons Creek and Tributaries, Bryan, Texas, December 1975. 2. The Handbook of Texas, Texas State Historical Association, 1952. 3. Texas Almanac, Dallas Morning News, 1986-1987. 4. U. S. Army Corps of Engineers, Fort Worth District, Problem Identification Study, Brazos River Basin, Texas, September 1987. 5. U. S. Army Corps of Engineers, Fort Worth District, Flood Problems Identification Study, Brazos River Basin, Texas, December 1987. 6. U. S. Army Corps of Engineers, Fort Worth District, Flood Plain Information, Carter s Creek and Tributaries, Bryan and College Station, Texas, December 1973. 7. U. S. Army Corps of Engineers, Fort Worth District, Hydrology Memorandum, Carters Creek Flood Plain Study, 1975. 8. U. S. Army Corps of Engineers, Fort Worth District, Special Flood Hazard Infomation, Turkey Creek, Bryan, Texas, December 1975. 35 THE WAL LACE GROUP, INC. E N G I N E E R S A R C H I T E C T S P L A N N E R S S U R V E Y O R S PEBBLE CREEK, PHASE 9-A - 19.65 ACRES FIELD NOTES FOR A 19.65 ACRE TRACT OF LAND LOCATED IN THE S.W. ROBERTSON ev A c o SURVEY, ABSTRACT NO. 202, BRAZOS COUNTY, TEXAS, AND BEING OUT OF THE T IEL"'1 P L E RESIDUE OF A CALLED 505.19 ACRE TRACT DESCRIBED AS TRACT 1 IN A DEED TO A S T I N D A A L L A S PEBBLE CREEK DEVELOPMENT COMPANY, RECORDED IN VOLUME 1671, PAGE 276 OF THE OFFICIAL DEED RECORDS OF BRAZOS COUNTY, TEXAS. SAID 19.65 ACRES BEING MORE PARTICULARLY SHOWN ON THE ATTACHED PLAT OF WHICH IS MADE A PART HEREOF AND DESCRIBED BY METES AND BOUNDS AS FOLLOWS: BEGINNING AT A'/2" DIAMETER REBAR FOUND MARKING THE EAST CORNER OF LOT 5, BLOCK 33 OF PEBBLE CREEK, PHASE 8-A, RECORDED IN VOLUME 3298, PAGE - 239 OF SAID DEED RECORDS, MARKING A CORNER OF THE ABOVE MENTIONED RESIDUE OF THE 505.19 ACRE TRACT AND THE MOST NORTHERLY CORNER OF THE HEREIN DESCRIBED TRACT; - THENCE THROUGH THE INTERIOR OF THE RESIDUE OF THE 505.19 ACRE TRACT THE - FOLLOWING THIRTY ONE (31) COURSES: Senn Flaherty, R.PL.S. Kocin He-l, R.P.L.S. 1) S 40-06'10" E - 149.50' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE Gcorge)eeck,AA.A- POINT, Mike Kc,ihcy, P.E., R.PLS. D,,, id a,.rek, PE. 2) S 10°03'26" E - 51.87' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE POINT, Brian A. M c Daeicl, PE. Thomas 1. Mireur)r., R.PL.5. 3) S 63~°70T4'22" E - 176.24' TO A E/2" DIAMETER REBAR PLACED FOR AN ANGLE Dan Nixon, R.PL-S. POI1V 1 , ).A. 7akr" P.rvlasJr., PE. S' Posey, R.P.L.S. 4) AN ARC DISTANCE OF 61.83' ALONG A CURVE TO THE RIGHT HAVING A Lynn Sims,-, R.P.LS. 1 Da,i(l P Sreith, RE. RADIUS OF 225.00' AND WHOSE CHORD BEARS S 34048'00" W - 61.64' TO A /2" Darrell v" Wa,lkeA.r, I. Jr., A.RE. E . "Jed' Walker, DIAMETER REBAR PLACED FOR AN ANGLE POINT, George R.E.'Bo6 W,11-e, RE., R.F.L.S. 5) S 47-19'37" E - 132.84' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE Ott~, E. 6%,vdcrhold, RE. POINT, )ohe F. Winkler, P.E. 6) S 49°53'50" W - 20.00' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE POINT, 7) S 42°35'32" E - 129.67' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE - POINT, - 8) AN ARC DISTANCE OF 5.19' ALONG A CURVE TO THE LEFT HAVING A RADIUS OF 475.00' AND WHOSE CHORD BEARS N 47°05'41" E - 5.19' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE POINT, - 9) S 43-13'05" E - 50.00' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE POINT, 10) S 57°04'31" E - 136.37' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE POINT, 11) S 14°28'42" E - 236.40' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE - POINT, 12) S 03°06'43" E - 55.78' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE POINT, 13) S 22-37'12" W - 110.31' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE POINT, 14) S 48°21'07" W - 55.78' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE POINT, 15) N 33-04'14" W - 137.00' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE POINT, 16) AN ARC DISTANCE OF 34.86' ALONG A CURVE TO THE RIGHT HAVING A P.O. Box 22007 RADIUS OF 50.00' AND WHOSE CHORD BEARS S 76°54' 10" W - 34.16' TO A 1/2" Waco, Texas 76702 DIAMETER REBAR PLACED FOR AN ANGLE POINT, 8225 Central Park Drive Suite 100 Waco, Texas 76712 (254)772-9272 (300)336-1683 Tax (254) 776-2924 vdw%%.Wallace-grou P.com 17) S 06°52'34" W - 137.00' TO A'/z" DIAMETER REBAR PLACED FOR AN ANGLE POINT, 18) N 73°50'09" W - 60.39' TO A 1/z" DIAMETER REBAR PLACED FOR AN ANGLE POINT, 19) N 45°57'23" W - 119.19' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE POINT, 20) N 06°32'26" W - 59.40' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE POINT, 21) S 82-20'16" W - 61.74' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE POINT, 22) S 49°53'50" W - 220.00' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE POINT, 23) S 23°35'09" W - 135.89' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE POINT, 24) N 82°01'58" W - 90.00' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE POINT, 25) S 07°58'02" W - 190.00' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE POINT, 26) N 82°01'58" W - 10.00' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE POINT, 27) S 07°58'02" W - 155.73' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE POINT, 28) S 88°53'26" W - 101.27' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE POINT, 29) N 82°01'58" W - 60.00' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE POINT, 30) N 07°58'02" E - 61.70' TO A 1/2" DIAMETER REBAR PLACED FOR AN ANGLE POINT, 31) AND N 82°01'58" W - 136.35' TO A 1/2 DIAMETER PLACED IN THE SOUTHEASTERLY LINE OF LOT 86, BLOCK 25 OF PEBBLE CREEK, PHASE 8-C, RECORDED IN VOLUME 4113, PAGE 64 OF SAID DEED RECORDS, MARKING A SOUTHWEST C ORNER OF THE HEREIN DESCRIBED TRACT; THENCE ALONG THE EAST LINE OF PEBBLE CREEK, PHASE 8-C AND PHASE 8-A THE FOLLOWING ELEVEN (11) COURSES: 1) N 45°16'58" E - 13.25' TO A 1/2" DIAMETER REBAR IN CONCRETE FOUND FOR AN ANGLE POINT, 2) N 07°58'02" E - 304.66' TO A 1/2" DIAMETER REBAR IN CONCRETE FOUND FOR AN ANGLE POINT, 3) N 25°33'31" E - 104.30' TO A 1/2" DIAMETER REBAR IN CONCRETE FOUND FOR AN ANGLE POINT, 4) N 40-06'10" W - 180.00' TO A 1/2" DIAMETER REBAR IN CONCRETE FOUND FOR AN ANGLE POINT, 5) N 49°53'50" E - 180.00' TO A 1/2" DIAMETER REBAR IN CONCRETE FOUND FOR AN ANGLE POINT, 6) AN ARC DISTANCE OF 89.45' ALONG A CURVE TO THE LEFT HAVING A RADIUS OF 225.00' AND WHOSE CHORD BEARS N 51°29'32" W - 88.87' TO A 1/2" DIAMETER REBAR IN CONCRETE FOUND FOR AN ANGLE POINT, 7) N 27°50'06" E - 159.21' TO A 1/2" DIAMETER REBAR IN CONCRETE FOUND FOR AN ANGLE POINT, 8) N 40-06'10" W - 80.81' TO A 1/2" DIAMETER REBAR IN CONCRETE FOUND FOR AN ANGLE POINT, 9) N 17-13'04" E - 368.30' TO A 1/2" DIAMETER REBAR IN CONCRETE FOUND FOR AN ANGLE POINT, 10) S 40-06'10" E - 73.88' TO A'/z" DIAMETER REBAR IN CONCRETE FOUND FOR AN ANGLE POINT, 11) AND N 49°53'50" E - 310.00' (BASE BEARING -PLATTED CALL) TO THE POINT OF BEGINNING. co: 4k 1 SURV *141, , 2 1 VIN . .P. .S. NO. 53 4 WO# 12671 PLAT D-1438 12671-FN- l O.DOC MAP CHK'D BY SRJ 36 < 33 ~ OV G^q I ~N Scale = 1: 366 (Feet) S 40° 06' 10" E 149.50 S 10° 03' 26" E 51.87 S 63° 04'22" E 176.24 S 34° 48'W, ch 61.64, r 225.00 R S 47° 19'37" E 132.84 S 49° 53'50" W 20.00 S 42° 35'32" E 129.67 N 47° 05'41 " E, ch 5.19, r 475.00 L S 43° 13'05" E 50.00 S 57° 04' 31" E 136.37 S 14° 28'42" E 236.40 S 03° 06'43" E 55.78 S22°37'12"W 110.31 S 48° 21'07" W 55.78 N 33° 04' 14" W 137.00 S 76° 54' 10" W, ch 34.16, r 50.00 R S 06° 52'34" W 137.00 N 73° 50'09" W 60.39 N 45° 57'23" W 119.19 N 06° 32'26" W 59.40 S 82° 20' 16" W 61.74 S 49° 53'50" W 220.00 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 S 23° 35'09" W 135.89 24 N 82° 01'58" W 90.00 25 S 07° 58'02" W 190.00 26 N 82°01'58" W 15.00 27 S 07° 58'02" W 156.53 28 S 88° 53'23" W 101.27 29 N 82° 01'58" W 50.00 30 N 07° 58'02" E 62.50 31 N 82° 01'58" W 141.35 32 N 45° 16'58" E 13.25 33 N 07° 58'02" E 304.66 34 N 25° 33'31" E 104.30 35 N 40° 06' 10" W 180.00 36 N 49° 53'50" E 180.00 37 N 51 ° 29' 32" W, ch 88.87, r 225.00 L 38 N 27° 50'06" E 159.21 39 N 40° 06' 10" W 80.81 40 N 17° 13'04" E 368.30 41 S 40° 06' 10" E 73.88 42 N 49° 53'50" E 310.00 woo le4op 2."r VRoV 411~ 400, C~ 3A Z a N / 9 lop 1 t~r~c~rn o~ •3oz d s X, I/