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FS9903-SY 941013 FLOOD STUDY EAST AND WEST SPLIT FLOW BETWEEN SANDY LAKE ROAD AND RIVER CHASE ROAD IN COPPELL, TEXAS BY MORRISON HYDROLOGY/ENGINEERING, INC. 520 AVE. H EAST SUITE 102 ~RLINGTON, TEXAS 76011 (817) 640-4554 TABLE OF CONTENTS Introduct ion Hydraulic Analysis Summary Tables Table 1 Table 2 comparison Between Existing and Proposed Condition 100 Year Flood Levels West Split Summary of Existing Condition 100 Year Flood Levels East Split Figures Figure i Location Map Appendices 1. West Split Denton Creek and Elm Fork Trinit~ River Existing conditions HEC-2 computer Printouts, cross Sections~ and Water Surface Profiles 2. West Split Denton Creek and Elm Fork Trinity River Proposed Conditions HEC-2 Computer Printouts~ cross Sections, and Water Surface Profiles 3. East Split Denton Creek and Elm Fork Trinity River Existing Conditions HEC-2 Computer Printouts, Cross Sections, and Water Surface Profiles 4. Floodplain Delineations ~ Introduction A 10 acre tract lies east of MacArthur Boulevard and south of Sandy Lake Road as shown in Figure 1. The purpose of this study is to determine the impact of filling this site along with the other development projected for the area. It is particularly important to determine any impact that might affect flooding at the apartment complex Just north of the project. Hydraulic Analysis The current FEMA Flood Study maps show a flood elevation difference at River Chase Road of 2 feet. No study was ever completed in this area to verify this assumption. It was simply assumed because the backwater from Denton creek and the backwater from the Elm Fork of the Trinity River st this point had a difference of 2 feet. The 100 year flood level overtops River Chase according to the latest topographic maps. In addition, the culvert under River chase is underwater from ponds on either side of River Chase. These ponds are at the same elevation during static conditions~ and as the flood levels slowly rise from the Trinity backwater, this level would continue to maintain the same elevation. Because of this discussion, it is apparent that the 100 year flood levels should be approximately equal at River Chase Road. This report assumes an equal elevation of 444 feet on both sides of River Chase. Using the above starting condition, a split flow model was completed for the east and west flowpath upstream to Bandy Lake Road. A rating was completed for each of these models to determine the flow that would produce an effective elevation at Sandy Lake Road of 466 feet to match the FEMA flood elevations at that location. The result was that 370 cubic feet per second (cfs) flow travels the west path and 1155 cfs flow travels the east path in order to produce the flood elevation found. Using the above flow a separate model was created for the east and west split flows (appendix i and 3) and a floodplain delineated (appendix 4). This existing condition model was used as a base to compare proposed changes. The proposed condition analysis involved modeling a channel that would carry the west flow (370 cfs) without causing an increase in flood elevations. This channel was extended from the subject property downstream past Starleaf Road. It is assumed that a bridge or culvert would be sized at Starleaf that would not cause any head loss. · he resulting channel :% oJj id; j%l{rV vrZ Sr . bottom width, 3tl side slopes, and The average velocities in this channel range from 2.2 to 2.7 feet per sJcond which is well within the lacceptable range of non erosive velocities for a grass lined channel. The computer model for this channel is provided in appendix 2. Summary This report has demonstrated that a 75 feet wide~jr~es lined channel with 3~1 side slopes at a slope of 0.15% would contain the 100 year flow generated in the west split without causing an increase in flood elevations. Page -2- Naturally, the proposed channel does not correct the problems at the apartment complex at MacArthur and Sandy Lake Road. The purpose of this study is to verify that the channel does not make the situation worse. TABLE 1 COMPARISON BETWEEN EXISTING AND PROPOSED 100 YEAR FLOOD LEVELS WEST SPLIT EXISTING CONDITION SEC. FLOOD Q VEL. NO. LEVEL I 444 1525 0,85 2 444.02 1525 3.04 3 444.68 1525 0.78 4 444.87 372 1.33 5 445.51 372 1.24 6 445.74 372 0.45 7 445.87 372 0.79 ~4~46/ 372 0.3 PROPOSED CONDITION 8EC. FLOOD Q VEL. NO. LEVEL I 444 1525 0,85 2 444.02 1525 3.04 3 444,68 1525 0.78 4 444.82 372 2,22 5 445.07 372 2.42 6 445.45 372 2,65 7 445.78 372 2,65 8 372 0.3 SEC. NO. TABLE 2 EXISTING (CONDITION 100 YEAR FLOOD LEVELS EAST SPLIT FLOOD Q VEL. LEVEL I 444 1525 0.85 2 444.02 1525 3.05 3 444,68 1525 0.78 4 444.84 1155.9 0,86 5 444.99 1155.9 1.11 6 445.07 1155.9 0.9 7 445.28 1155,9 1.58 8 446 1525 1.22 r9 FIRM FLOOD INSURANCE HATE MAP STREET fHDEX CITY OF COPPELL TEXAS L)ALI,A,~ AND DF, NION COUNTIE~ ZONE X ZONE X4 ZONEX ZONE X DRiV ONE X COMMIiNITY.PANEL Ngfilil 480170 0010 E RAPREVISED: APRIL 10, 1994 , ,- WEST SPLIT DENTON CREEK ELM FORK TRINITY RIVER EXISTING CONDITIONS HEC-2 MATER SURFACE PROFILES Version 4.6,0; [ebruarv RUN DATE {30CT94 TIRf 15:28:54 U.5. ARMY CORPS OE ENGINEERS HYDROLOGIC ENGINEERING CENTER 609 SECOND STREET. SUITE D DAVIS, CALIFORNIA 956)6-468) (D)6) 756-))04 X X XXXXXXX XXXXX XXXXX X X X X X X X X X X X X XXXXXXX XXXX X XXXXX XXXXX X X X X X X X X X X X X X XXXXXXX XXXXX XXXXXXX 130CT94 15:28:54 PAGE I HEC-2 WATER SURFACE PROFILES Version 4,6.0: February I993 THIS RUN EXECUTED 130CT94 15:28:54 TI T2 T3 31 J2 NEST SPLET DENTON CREEK ElN FORM TRENITY RIVER lO0 YEAR FILE: NESTEXT ICHECK ENQ NINV IDIR STRT 0 2 O 0 0 NPROF IPIOT PRFVS XSECV XSECH NETRIC HV[NS 0 WSEI 0 0 0 444 FN ALLDC tBW CNNIN FO ITRACE VARIABLE CODES FOR SUNMARY PRINTOUT 38 1 43 42 4 53 54 26 J5 LPRNT NUWSEC SECTION NUNBERS*"**"* -~0 OT I 1525 NC ,06 ,06 .06 X1 ~ ~8 935 GR 448 620 446 GD 438 980 436 GR 442 HRS 443.6 GR 446 1335 446 .1 ,3 ]185 800 444 815 442 ]OlO 435 1355 438 1220 442 1260 444 1350 448 1640 935 440 960 1170 440 1180 1310 446 1325 Xl 2 12 940 1045 400 400 400 GR 446 750 444 790 443.6 870 442 946 440 GR 438,4 3000 440 1030 442 1045 444 1110 445.1 GR 446 1290 447 1440 XI 3 14 680 1310 350 1100 1075 GR 447.1 200 446 560 444 680 442 830 440.9 GR 440 1130 440 1150 ~ ]290 444 1310 446 GR 446.5 {520 448 3775 449 2030 450 2230 Or I 372 Xl 4 9 925 1060 740 750 720 GR 448 310 446.7 510 446 725 444 GR 442 970 444 lOGO 446 1320 448,6 925 442 965 HI0 1030 1360 960 130CT94 PAGE X] 5 12 840 960 340 425 380 GR 448 510 44G 690 445 840 444 GR 445 960 444.4 1135 446 1310 448 GR 448 ]580 450 1610 875 1500 Xl 6 14 660 1365 380 420 400 GR 448 5VO 446 660 444 810 444 860 GR 444.3 1~70 446 1365 448 1410 450 1430 GR 454 1500 456 1510 458 1520 4GO 1530 7 448 448 8 530 1450 770 446, 450 1360 280 300 290 770+, .4~4 9.40. 445.1 1480 452 1500 X1 GR GR 1120 XJ 8 14 7]5 1080 850 850 850 GR 448 580 446 680 444 715 443.5 1000 GR 446 HIS 446 1160 444 I]90 444 ]355 GR 447 2130 446 2300 448 2320 450 2350 444 448 444 452 446 444 446 885 1550 970 1480 1360 1080 1465 130CT94 ]5:?8:54 PAGE HEC-2 NATER SURFACE PROFILES Version 4.6.0; February THIS RUN EXECUTED 130CT94 35:28:55 NOTE- ASTERISK (*) AT LEFT OF CROSS-SECTION NUMBER tNOICATES MESSAGE IN SUMMARY OF ERRORS LIST F' 100 YEAR FILE: SUMMARY PRINTOUT SICNO CHSEI O ELMIN TOPWID SSTA ENOST ],000 444.00 1525.00 436.00 495.00 8]5,00 13]0.00 * 2.000 444.02 ]525.00 438.40 322.12 789.43 1]]].55 * 3.000 444,88 J525.00' 440,00687:]0 ""639;69"1326.70 * 4.000 444.87 372.00 442.00 248.07 838.02 ]086.09 8.000 445,5] 372.00 444,00 494.]7 762.77 ]256,94 * 6.000 445,74 372.00 444.00 656.74 679.08 {335.82 * 7.000 445,87 372,00 444.00 546,45 780.53 1326.98 * 8.000 446,00 372.00 443.50 785.05 680.00 2300.00 VCH ,85 3.04 1,33 ,46 ,30 J30CT94 15:28:54 SUMMARY OF ERRORS AND SPECIAL NOTES NARNING SECNO= 2.000 PROFILE= NABRiNG SECNO: 3.000 PROFILE: NARNiNG SECNO: 4.000 PRHFZLE= NARNiNG SiCNO= 6.000 PROFILE= HARNING 5[CNO= 7.000 PROFTLE: NARNZNG SiCNO= 8.000 PROFILE= CONVEYANCE CHANGE OUTS]HE ACCEPTAHLE RANG[ CONVEYANCE CHANGE OUTSIDE ACCEPTAHLE RANGE CONVEYANCE CHANGE OUTS]DE ACCEPTABLE RANGE CONVEYANCE CHANGE OUTSTDE ACCEPTABLE RANGE CONVEYANCE CHANGE OUTS[DE ACCEPTABLE RANGE CONVEYANCE CHANGE OUTSIDE ACCEPTAHLE RANGE PAGE I I I I ) I ! ! I ) I I I I I I I 460 455 __ Z 450 __ 445 __ 440 __ 435 12~0 STATION 18~0 SECTION : 1 460 455 -- 450 -- 445 __ 440 _ 435 6C0 16~0 18~0 2010 2230 SECTION = 2 I ! 1 I 1 ) ) ! I I I I 460 7 r-1 455 __ 450 _ STATIDN 2E ~0 SECTION : 3 1 I 1 1 '! 1 I I I ! I I 460 455 -- Z 450 _ 445 __ 440 __ 435 STATIRN 14~0 1610 SECTIDN : 4 I } 1 ) I I I ) ] I 1 1 1 1 I I I I 7 460 455 __ 450 __ 445 __ 440 _ STATION 18! 0 SECTION: 5 I ! i 1 I ! I I I 1 465 [] 460 _ 455 __ 450 __ 445 __ 1010 STATIDN 18[0 SECTIDN ~ 6 I I 1 I I I 1 I I I ! ! · · "1 I 1 I I 465 460 __ Z 455 -- 450 __ 445 __ 440 2C0 4d0 STATION SECTIrlN ~ 7 I I I I I I ! } I ! I 1 I ! I ! ) 1 I 465 rn w w 460 __ 455 __ 450 __ 445 __ 440 5C0 7JO llOlO STATIDN 17~0 19~0 21~0 SECTION: 8 I 1 I 1 ! I ! I I 1 ! I I I I I I I UI WEST SPLIT DENTON CREEK ELM FORK TRINITY RIVER PROPOSED CONDITIONS * HEC-2 HATER SURFACE PROFILES * Version 4.6,0; February ]99] * RUN DATE 130CT94 TiRE * U,S. ARRY CORPS OF ENGINEERS * HYDROLOGiC ENGEREERENG CENTER * 609 SECOND STREET, SUITE O * DAVES, CALIFORNIA 95616-4687 X X XXXXXXX XXXXX XXXXX X X X X X X X X X X X X XXXXXXX XXXX X XXXXX XXXXX X X X X X X X X X X X X X XXXXXXX XXXXX XXXXXXX 130CT94 ~5:33:J6 PAGE 1 HEC-2 HATER SURFACE PROFELES Version 4,G.O: February 1991 THIS RUN EXECUTED 130CT94 )5:3R:36 TJ T2 T3 WEST SPLIT GRASSLINED CHANNEl 75' WIDE DENTON CREEK ELM FORK TRINITY RIVER ]00 YEAR FILE:WESTPROE J1 ICHECK ENO NINV ,tDIR . !T.RT 0 2 0 0 0 32 NPROF EPLOT PRFVS XSECV XSECH -] 0 0 0 0 FN ALLDC tBW WSEL FO 444 CHNIM ETRACE J3 VARIABLE CODES FOR SUHNARY PRINTOUT 38 I 43 42 4 53 54 26 J5 LPRNT NUHSEC ********REOUESTEO SECTION NUHBERS******** -10 -)0 OT ) 3525 NC .06 .06 ,06 X] ] 18 935 GR 448 620 446 GR 438 980 436 GR 442 i]85 443.6 GR 446 ]335 446 .3 .3 3385 800 444 815 442 )OJO 436 3)55 438 )220 442 3260 444 3350 448 1640 XI 2 12 940 GR 446 750 444 GR 438.4 1000 440 GR 446 ]290 447 935 ]]70 1310 X] 3 14 680 GR 447,1 200 446 GR 440 1130 440 GR 446,5 1520 448 1045 400 400 400 790 443.6 870 442 940 1030 442 )045 444 1]]0 )440 1310 350 1]00 ]075 560 444 680 442 830 1]50 442 · 1290 444 )775 449 2030 450 2230 .3 PLACE OT ) 372 NC .03 .03 .03 .] PROPOSED CONDITION WITH ALL DEVELOPMENT IN S=,00]586 3:1 SIDE SLOPES TW:75' ELMIN. 442 440 440 446 440 445.1 440.9 446 960 1180 1325 965 1030 1360 ~30CT94 15:33:16 PAGE XI4 13 985 1060 740 750 720 GR448 310 446,7 510 446 725 446 GR446 985 442 997 442 1048 446 GR448.6 H90 ELMIN= 442.6 925 1060 X15 14 895 970 375 375 375 GR448 510 446 690 446 840 446 860 GR442.6 905 442.6 960 446 970 446 1135 OR448 1500 448 1550 448 1580 450 1630 [LMIN. 443.3 XI 6 ]6 845 920 390 390 390 GR 448 570 446 660 446 845 443.3 GR 446 920 446 970 446 1170 446 6R 450 1430 452 ]480 454 1500 456 GR 460 ]530 ELMIN= 443.7 XI 7 12 835 910 280 280 280 6R 448 530 446 770 446 835 443.7 GR 446 910 446 940 446 1120 446 GR 450 1480 452 1500 NC .06 .06 .06 .1 .3 I] 8 14 716 1080 850 850 850 GR 448 580 446 680 444 716 443.5 GR 446 1115 446 JJ60 444 ]t90 444 GR 447 2130 446 2300 448 2320 450 853 1365 1510 842 1360 1000 1355 2350 446 446 446 446 443.3 448 458 443.1 448 444 446 960 1120 895 1310 912 1410 1520 903 1450 1080 1465 130CT94 15:33:16 HEC-2 WATER SURFACE PROFILES Version 4,6,0: February 1993 PAG[ NOTE- ASTERISK (*) AT LEFT OF CROSS-SECTION NUNBER INDICATES NESSAGE IN SUNNARY OF ERRORS LIST lO0 YEAR FILE: THIS RUN EXECUTEO 130CT94 15:33:]7 SUMMARY PRINTOUT SECNO C~SEL 0 EININ TOPNIO SSTA ENDST VCN 1.000 444,00 1525.00 436.00 4~5.00 815.00 ]310.00 .85 * 2.000 444.02 1525,00 438,40 322,12 789,43 1111.55 3,04 * 3,000 444.68 1525.00 440,00 687.10 639.69 3326.79 .78 * 4.000 444.82 372.00 442.00 67,92 988,54 1056,48 2.22 5.000 445.07 372.00 442.60 69.55 897.73 967.27 2.42 8.000 445.45 372.00 443,30 73.71 846.64 918,36 2.65 7.000 445,78 372.00 443.70 73.69 835.66 909,34 2.65 * 8,000 446.02 372,00 443.50 799,97 679.16 2300.17 .30 130CT94 15:33:16 SUMMARY OF ERRORS AND SPECIAL NOES NARNING SECNO= HARNING SECNO= NARNING SECNO= tARRING SECNO= 2,000 PROFILE: 3.000 PROFILE: 4.000 PROFILE: 8.000 PROFILF: CONVEYANCE CHANGE OUTSIDE ACCEPTABLE RANGE I CONVEYANCE CHANGE OUTSIDE ACCEPTABLE RANGE 1 CONVEYANCE CHANGE OUTSIDE ACCEPTABLE RANGE I CONVEYANCE CHANGE OUTSIDE ACCEPTADLE RANGE PAGE 460 Z rn 455 __ 450 __ 445 440 435 SECTION , 1 1210 STATIDN 1810 20~'0 2 30 · ~ .... '1 .... ~ "1 ' ="1 ' 'l .... 1 .... 1 1 I ..... 1 ..... 1 ! "1 '1 .... ! I I I 460 '7 455 __ 450 __ 445 __ 440 __ 435 6C0 8JO SECTION:2 STATION 1610 18~0 20~0 ]0 z 460 455 __ 450 __ 445 SECTIDN=3 22 )0 ! 460 455 _ rl 450 _ 445 _ 440 _ 435 8[0 4JO SECTIDN: 4 STATIDN 1410 16~0 460 455 __ Z [] 450 __ 445 _ 440 ' 435 ~[0 4~0 SECTIDN: 5 18( I ' ! "'1 I ' '1 465 [::]: ~.. > 460 _ 455 __ 450 __ 445 __ SECTtDN 1010 STATIDN I I ] I '1 'l 1 '1 ~ ~ ' '~ ..... 1 1 ' I I 1 465 460 __ 455 _ 450 __ 445 __ 440 8EO 4~0 SECTIDN: 7 18( 0 465 460 __ 455 _ 450 __ 445 __ SECTION: 8 13~0 STATIDN 1510 17~0 I I 1 1 ! '1 1 I '1 I I I ! I I I EAST SPLIT DENTON CREEK ELM FORK TRINITY RIVER EXISTING CONDITIONS DEC-~ ~ATER SURFACE P~OFILE~ Version 4,~.0: February RUN DAT~ ~3DCT~4 Tiff ~3:27:04 U.S. AR~Y COR~5 OF ~YDROIO~tC [NUNEE[(ING CENTER 609 SECOND STREET, SUIIE 0 DAVIS, CALIFORNIA 9561G-4687 (916) 755-1104 X X XXXXXXX XXXXX XXXXX X X X X X X X X X X X X XXXXXXX XXXX X XXXXX XXXXX X X X X X X X X X X X X X XXXXXXX XXXXX XXXXXXX i30CT94 13:27:04 PAGE HEC-2 WATER SURFACE PROFILES Version 4.6.6; February 19H] THIS RUN EXECUTFD J30CT94 ]3:27:04 SPLIT FLOW HEING PERFORMED SF SPLIT FLOW FOR THE WEST FLOWPATH TC HATING CURVE FOR THE WEST FLOWPATH I OF PAIRS US SECT US SECT O RET CS 9 8 8 3 SECTION ) WEST FLOWPATH RATING ~RVf CR )OO 445.16 200 445.57 400 CR |000 446.9) 1200 44).1) )400 44d.08 '~6'0 446:42 447.28 1600 447.44 446.68 130CT94 t3:27:04 PAGE 2 TI EAST SPLIT EXISTING CONDITION T2 DENTON CREEK ELN FORK TRINITY RIVER T3 100 YEAR FILE: EASTEXT Jl ICHECK INO NINV IDIR 0 2 0 0 J2 NPROF tPLOT PRFVS XSECV -1 0 -1 STRT METRIC HYTNS O 0 0 O 0 XSECH FN ALLDC ION NS[L 444 CHNIN FO ITRACE 33 VARIABLE CODES FOR SURNARY PRINTOUT 38 J 43 42 4 53 54 26 35 LPRNT NUMSEC ********REOUESTED SECTION NUMBERS******** -10 -JO OT 1 1525 NC ,06 .06 .06 XI 1 18 935 GR 448 620 446 GR 438 980 436 GR 442 1185 443.6 GR 446 1335 446 ,) .3 1185 800 444 8J5 442 JOJO 436 1J55 438 )220 442 )260 444 1350 448 J640 Jl 2 J2 940 GR 446 750 444 GR 438,4 JO00 440 GR 446 1290 447 J045 400 400 400 790 443,6 870 442 1030 442 1045 444 1440 XJ 3 14 680 6R 447.1 200 446 GR 440 1130 440 GR 446.5 1520 448 935 JJTO 1310 XJ 4 JO 790 GR 447,1 535 446 GR 442 J21B 444 940 1110 XJ 5 9 8J0 GR 448 560 446 GR 442 1200 444 1310 350 1)00 1075 560 444 680 442 830 1150 442 1290 444 1310 J775 449 2030 450 2230 X1 6 9 GR 448 600 GR 442 H95 1225 450 550 700 7J0 444 790 442 1225 446 J250 446.7 J2JO 400 350 400 780 444 810 442 J210 446 )285 448 795 J2JO 185 185 446' 755 ~4i 795 444 J2)0 446 185 442 448 8J5 1455 84O 1420 925 440 440 448 440 445.1 440.9 446 441,3 448 442.7 440.9 960 )180 1325 965 t170 1030 1360 1000 1650 lJ)5 1135 330CT94 33:27:04 PAG[ 3 Xl 7 7 760 1380 6R 448 650 446 740 GR 446 1270 448 1450 375 375 375 444 760 443.2 940 X] 8 14 7]5 1080 580 600 600 GR 448 580 446 680 444 7]5 443.5 1000 GR 446 ]]]5 446 3360 444 3]90 444 3355 GR 447 H30 446 2300 448 2320 450 2350 444 444 446 1180 1080 1465 HEC-2 WATER SURFACE PROFILES Vernon 4,6.0: February THIS RUN EXECUTED 330CT94 13:27:07 NOTE- ASTERISK (*) AT LEFT OF CROSS-SECTION NUNBER INDICATES NESSAGE IN SUNNARY OF ERRORS LIST 300 YEAR FILE: SUMMARY PRINTOUT 9ECNO 6~SEL ].000 444.00 * 2.000 444.02 t 3.000 444.68 * 4.000 444,84 * 5,000 444.99 6.000 445,07 * 7.000 445,28 * 8,000 446.00 0 ELMIN TOPWID SSTA ENDST 1525.00 436.00 495.00 815.00 1310.00 1525.00 438.40 321.56 789,58 ]]11.14 ]525.00 ' 440.00 "687.75""639.2'4"1326.98 1155.90 441.30 478.76 756.66 1239.42 1155.90 442.00 451.76 795.21 1246.97 1155.90 440.90 471.~4 773.61 1244.75 ]155.90 443,20 490.59 747,]7 ]237.76 ]525,00 443,50 739,6] 680.07 ]454.80 VCH .85 3.05 ,86 ,90 1.58 1.22 I30CT94 33:27:04 PAGf 5 SUMMARY OF ERRORS AND SPECIAL NOTES NARNINO SECNO, 2.000 PROFILE: ! WARNING SECNO: 3.000 PROFILE: WARNING SECNO: 4,000 PROFilE: WARNING SECNO: 5,000 PROFFIE: ""' WARNtWO SECNO: 1.000 PROFELE: NARNING SECNO, 8.000 PROF[LE= CONVEYANCE CHANGE OUTSFOE ACCEPTABLE RANGE CONVEYANCE CHANGE OUTSiOE ACCEPTABLE RANGE CONVEYANCE CHANGE OUTSFOE ACCEPTABLE RANG[ CONVEYANCE CHANGE OUTSIDE ACCEPTABLE RANGE CONVEYANCE CHANGE OUTSIDE ACCEPTABLE RANGE CONVEYANCE CHANGE OUTSIDE ACCEPTABLE RANGE ELEVATION 600 8OO 1000 460 445 450 455 460 1200' 1400 1600 1800 2000' 2200 I BECTION: 1 F,~BT BPLIT EXIBTING CONDITION ELEVATION 435 600 440 445 I 450 455 460 8O0 1000 1200 1400 1600--- 1800--- 2000 2200 BECTION: 2 EABT BPLIT EXIBTING CONDITION ELEVATION 435 440 445 600 J 800~- . . 1000 . 1200 . . 1400 1600 1800 200O-- 2200 450 455 460 BECTION ~ 3 EABT BPLIT EXIBTINO CONDITION ELEVATION 435 400 440 445 450 I 455 & 460 600 800 1000 1200--- 1400-- 1600 1800 2000 SECTION I 4 F~BT BPLIT EXISTING CONDITION ELEVATION 435 400 440 445 I 450 455 460 600 800--- 1000 ZSQO X400 1600 ' 1800--- 2000 i SECTION I 5 F~ST SPLIT EXISTING CONDITION ELEVATION 435 440 445 450 455 400 I I J I 460 600 800--.- 1000 1200 1400--- 1600 1800- 2000 BBCTION ~ 6 EABT 8PLIT EXIHT~G~0ND'ITION ELEVATION 435 400 440 445 450 455 460 6OQ 8OO--- 1000--- 1200 1400 1600 1800 2000 BECTION I 7 EAST BPLIT EXISTING CONDITION ELEVATION 435 600 440 445 450 455 460 800 1000 1200 1400 1600 1800--- 2000--- BBCTION ~ I / 8 F&BT BPLIT BXIBTING CONDITION 430 0 500 1000--- 1500 2000' 2500 3000 3500 435 I \ 440 \ 4 \ \ k 7 ' 8 445 450 I 455 4000 EABT B~LIT BXIBTIHO CONDITION WEST SPLIT DENTON CREEK ELM FORK TRINITY RIVER FLOODPLAIN DELINEATIONS