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Big Cedar-SY 920827FLOODPLAIN ANALYSIS for a Final LOMR for a Portion of TRIBUTARY G-1 of GRAPEVINE CI~EEK City of Coppell, Dallas County, Texas Prepared For: Matthews Investments Southwest, Inc. August, 1992 Prepared by CIVE~ ~)ODWIN ~ ENGINEERS ~ PLANNERS 6001 Bridge Street, Suite 100 Fort Worth, Texas 76112 FINAL "AS BUILT~ CONDmONS FLOODPLAIN ANALYSIS for TRIBUTARY G-I of GRAPEVINE CREEK City of Coppelk Dallas County, Texas TABLE OF CONTENTS Page Number INTRODUCTION .......................................................... 1 Purpose ............................................................... 1 Project Location ........................................................ ENGINEERING METHODOLOGY ............................................ 2 General ............................................................... 2 Hydrologic Analysis ...................................................... 3 Hydraulic Analysis ....................................................... 4 Existing Conditions ................................................. 4 Proposed Improved Conditions ........................................ 4 'As Builff Improved Conditions ........................................ 4 Floodway ......................................................... 5 TABLES TABLE ONE - Peak Discharges at the Confluence of Tn"outary G-1 and Grapevine Creek .......................................... 3 TABI.F~ TWO - "As Builffand Proposed Improved Conditions 100-Year Water Surface Elevations and Velocity Calculations ................................... 6 TABI.~ OF CONTENTS (Continued) FIGURES Figure 1 ...................................................... Location Map Figures 2 through 11 .................................... Tributary G-1 Cross-Sections Figure 12 ...................... 100-Year Water Surface Profiles for Existing Watershed Plate 1 Plate 2 Plate 3 PLATES ............... Proposed Improved Conditions 100-Year Floodplain Delineation ...................... "As Built" Conditions 100-Year Floodplain Delineatiom ........................................... "As Built" Reclamation Plan APPENDIX A APPENDIX B APPENDIX C ................. APPENDICES .............................. Conditional LOMR and Fill Certification ........................ "As Built" Conditions Hydraulic Model & Results "As Built" Conditions Floodway Hydraulic Model & Results Final "As Built" Conditions Floodplain Analysis for Tributary G-1 of Grapevine Creek City of Coppell, Dallas County, Texas INTRODUCTION PURPOSE The purpose of this report is to document final "As Built" conditions for a proposed development adjacent to Trfoutary G-1 of Grapevine Creek in Coppell, Dallas County, Texas. In August of 1991, on behalf of the current owners of the property, Goodwin and Marshall, Inc. (G&M) prepared a floodplain analysis of Tributary G-1. The analysis created the initial detailed hydrologic and hydraulic models for the tributary. In addition, the analysis requested a conditional Letter of Map Revision (LOMR) for a proposed reclamation program adjacent to the tributary. A conditional LOMR was issued by FEMA on November 18, 1992 for thc proposed project. The purpose of this report is to provide sufficient documentation to obtain a final Letter of Map Revision for the project as constructed in the riel& PROJECT LOCATION The property that is the subject of this floodplain analysis is located immediately west of Bethel School Road near its intersection with Bethel Road in the City of Coppell, Dallas County, Texas (see Figure 1). The project is bounded on the north by the Coppell Village subdivision, which was constructed in the early to mid 1980's. Tributary G-1 abuts the southern boundary of the proposed residential development. Floodplain Analysis for Tributary G-I of Grapevine Creek - Page I ENGINEERING METHODOLOGY GENERAL The initial flood prone area identification map of this regional Flood Hazard area was dated March 8, 1974. There have been several updates of the map, with the current effective Flood Insurance Rate Map (FIRaM) dated February 15, 1984. FEMA is currently in the process of updating the effective FIRM for the City of Coppell. The City had originally requested that a portion of the subject property be shown within the boundary of the 100-year floodplain and classified as a "non- detailed" study region. In August of 1991 G&M prepared a detailed hydrologic and hydraulic model for the tributary. This analysis was established as Case No. 91-06-70R by FEMA. As approved by FEMA, the analysis established the existing 100-year floodplain and corresponding floodway for the tributary. In addition, a proposed plan of improvements was approved conditional to several stipulations as follows: Evidence of compliance with NFIP regulations regarding Paragraph 65.4(b), which states that 'all requests for changes to effective maps must be made in writing by the community's Chief Executive Officer (CEO) or an official designated by thc CEO. Should the CEO refuse to submit such a request on behalf of another party, FEMA will agree to review it only if written evidence is provided indicating the CEO or designee has been requested to do Revised hydraulic analyses and floodplain mapping, if the 'as-built" condition differs from the proposed condition. "As-Built" certification by a registered professional engineer that the fill associated with this project has been placed in compliance with Subparagraph 65.5(a)(6) of the NFIP regulations. 4) "As-Built" plans of the fill project certified by a registered professional engineer. Floodplain Analysis for Tributary G-1 of Grapevine Creek - Page 2 It is the intent of this report to provide the documentation necessary to satisfy the conditions as outlined in the FEMA letter of November 18, 1991. A copy of the conditional LOMR is contained in Appendix A for the convenience of the reader. HYDROLOGIC ANALYSIS The details of the hydrologic analysis for Tffoutary G-1 were presented in the original analysis. This information was adopted based on acceptance of the study by FEMA. No significant changes to the watershed have occurred in the interim. Therefore the original hydrologic calculations as approved are still applicable. A summary of the peak discharges for the 10-, 50-, 100-, and 500-year frequency events as calculated for Tributary G-1 is given in Table One. Peak Discharges at the Confluence of Tributary G-1 and Grapevine Creek 10-Year Discharge .................................. 1860 cfs 50-Year Discharge .................................. 2735 cfs 100-Year Discharge ................................. 3140 cfs 500-Year Discharge ................................. 4210 cfs The HEC-1 printouts for the existing conditions 10-, 50-, 100-, and 500-year rainfall event can be found in the original documentation for the tributary. Floodplain Analysis for Tributary G-1 of Grapevine Creek - Page 3 HYDRAUUC ANALYSIS Exi~tinR Conditions The original existing conditions model as approved can be found in the initial project submittal Proposed Improved Conditions The proposed plan of improvements as approved conditionally by FEMA can be found displayed on Plate One. The actual HEC-2 model for the proposed plan of improvements ia contained in Appendix B of this analysis. "As Built" Improved Conditions The proposed reclamation plan was constructed in general conformance with the reclamation plan as proposed in the original submittal. However, some variances in construction from the original plan did occur. The main changes were that a short section of wall was constructed near cross-section 945. In addition, the amount of fill material placed between sections 1120 and 1960 was substantially reduced. The final configuration of the reclamation as constructed can be found on Plate Two. Certified "As Built" engineering plans can be found displayed on Plate Three. This plan resulted from on the ground field surveys upon completion of construction. A comparison of original proposed improved conditions and the final "As Built" conditions can be found displayed on Figures 2 through 11 respectively. Finally, the 100-year water surface elevation as calculated for the final improved conditions can be found on Figure 12. Table Two consists of a comparison between the original proposed improved conditions and the final "As Built" conditions. It should be noted that in all instances thc "As Built" elevations arc leas than those originally approved by FEMA. This ia due to the fact that less fill has actually been placed than originally approved. The one exception is at cross-section 12+80, which is 0.01 foot greater than previously approved. It has been previously described that the conditional LOMR was contingent upon satisfaction of four items. Attached to this report ia a letter from the City Engineer for the City of Coppell requesting Floodplain Analysis for Tributary G-1 of Grapevine Creek - Page 4 approval of the final LOMR. This letter serves to satisfy item (1) as discussed previously. This report documents the revised hydraulic analysis and floodplain mapping resulting from the slight variation in "As-Built" conditions from the approved plato This satisfies item (2) as previously disom;ed. Appendix A contains certification from the project materials engineer that the Fill placed in this project was compacted to a minimum of 95 percent of Standard Proctor density as determined by ASTM D-696. In addition, it should be noted that channel velocities throughout the region are generally less than four feet per second during the design storm. The only sections which excexxl the velocity of five feet per second are 124-80 and 144-50. It should be stressed that at these cross- sections the actual fill slope is in the left overbank region. Appendix B contains a detailed printout of the results of the final "As Built" conditions. Review of the detailed printout indicates that the velocities in this region are less than two feet per second. In addition, no fill slope for this project exceeds three horizontal to one vertical. This data satisfies stipulation (3) as previously described. Finally, Plate 3 contains "As Built" plans of the project certified by a registered professional engineer. Floodway The original approved floodplain analysis for Tn'outary G-1 as prepared by G&M established a regulatory floodway for the creek. The floodway location as approved has been duplicated for the "As Built" conditions modeL The results of the floodway model can be found contained in Appendix C of this report. It should be noted that the floodway run meets or exceeds all FEMA and City of Coppell requirements. Floodplain Analysis for Tributary G-1 of Grapevine Creek - Page 5 TABLF~ TWO p:xisting Conditions and Proposed Improved Conditions lO0-year Water Surface Profiles and Velocity Calculations WAs Built' Conditions Proposed Improved Section Number Conditions Elevation VelociO Elevation Velocity (fl~sec) (fl/sec) 1 +20 484.38 7.82 484.38 7.82 2+20 484.75 10.92 484.75 10.92 2+30 483.61 16.95 483.61 16.95 2+90 487.29 11.96 487.29 11.96 3 +40 489.81 5.00 489.81 5.00 5+60 489.85 14.24 489.85 14.24 7+70 493.58 3.20 493.58 3.20 9+45 493.72 3.17 493.71 3.61 11 +20 493.88 2.84 493.94 2.81 12+80 493.78 5.74 493.77 6.29 14+50 494.31 5.76 494.44 5.66 17+60 495.10 2.76 495.27 3.78 19+60 494.56 9.64 495.20 8.44 21 +35 496.58 2.95 496.63 2.84 26 + 15 497.23 6.20 497.30 6.1 ! 31 +25 499.50 7.12 499.50 7.10 35 + 15 501.33 7.35 501.33 7.35 Floodplain Analysis for Tributary G-1 of Grapevine Creek - Page 6 SUMMARY It has been shown that the reclamation project described herein has varied slightly from that originally approved for the project under FEMA Case No. 91-06-70R. All documentation has been provided to indicate that the project as constructed meets or exceeds all FEMA criteria for projects of this nature. In addition, all documentation has been supplied satisfying the criteria as established in the conditional LOMR for the project dated November 18, 1991, a copy of which is contained in Appendix A. Based on the information contained within this analysis, a final Letter of Map Revision for this project is warranted. Floodplain Analysis for Tributary G-1 of Grapevine Creek - Page 7 VICINITY MAP, RIVER RD. ~T ~ T.S. 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G, OODWIN ~ 1V~ AP, SI-IAI. I. CIVIL ENGINEERS-PLANNERS-SURVEYORS TRIBUTARY G-1 OF GRAPEVINE CREEK COPPELL, TEXAS 100-YEAR WATER SURFACE PROFILES EXISTING WATERSHED ' U. U » " 5uo ou� \ ,, � / ,' | {� ' -~ _ ,' - ~ . ^�}Q - � - SCALE NOTE: Topographic information based on interpolation of field surveyed cross-sections and City cfCoppeU two foot contour interval topographic maps. ^� -' /\<1v 0 ' ~ ' � ` ` ~ / ° 1� 0 NIIIIIIIIIIIIIIIII t l SCALE: 1" = 40' N /G 5081 , 0 828.20' N/G 5081 N 89 E ' N/6 5 07 8 , - ------------ 508 508 ___508 I \ x L0 L co 19 30 40 Irl 18 F.P. 507.5 20 29 F.P. 507.5 31 F.P. 507.0 F.P. 507.5 + F.P. 507.5 F.P. 507.5 ± F.P. 507.5 ± i - - -- - -- X `106 t, Q om, ' HAY BALE DIK PROTECTION EROSION PROTECTION 3 9 :)Ot> C F.P. 507.0 t 17 21 28 32 F.P. 506.3 F.P. 507.0 ± F.P. 507.0 F.P. 507.0 O 38 0 cc 0 16 F.P. 506.5 T_ 1 27 23 U) 502 F.P. 505.5 F.P. 506.5 ± F.P. 505.5/± 0� Y 0 506 uj w 50o-_ -, .. .\ \\ 10 1 1 23 ---26 ; �- W cc F.P. 5 0 10 M (V . F.P. 504.3 - -_F.P. 504.3 504 o z Z w 14 C"I k / � � � � i I \ - 25 I 1 F`P A + �� .� . � � 1 � I � �` • �\ - � ii F. .5oz � � \� F.P. 501.5 CONTRACTOR NOTE STRUCTURAL SLOPE 4. PROTECTION TO BE WLACE IN AREA OF 1 BALE DIKE PROTEOT16N 2:1 SLOPE LOCATION WITH ERH31 AN --EROSION PROTE_�Tehl F.P. 506.5 + Z 3 34 7 + F.P. 505.5 I FR 505.5 uj HAY BALE DIKE co EROSION PROTECTION r, 36 ul 35 __F P. 504.0 I C 50148 F.P. 504.3 ± INTERLOCKING BRICK OR A HIGH TENSILE I I I / 1 11 _ - rj - - - - - I C 4 STR1a4GTH PLASTIC WEBBING (Enkamt) WITH IVY OR HON TO SUPPLEMENT ° 0' SLOPE STABILTY. HOMEOWNER ASSOC. BROOK STREET RESPONS13LE FOR SLOPE MAINTENCE t /1 J, WITHIN BIG CEDAR EXCLUDING LOT 42- 13 � 12 F.P. 498.3_+ mum f \• F.F. 498.2 -''f CuG, \ �4(�� '�- �� 1 j �� E i JI/ 1 N \N F.F. 497.0 1 1 /--�\\\\\\ Ih FIF. 498.0 F.F. 499.0 F.F. 499.0 / / I ' / F.F. 497.0 A 3� 2 f Oi l I-A XrOF- 6 ' \ y ap •• I O A TO ......... . . 5 F.F. 498.0 w \ A �9 / . V A\ F.F. 497.0 4 C ) 4 �c 497 47 C 211�IN 6 ,c 492 L4j GRADE EAIIT��, 149.66' 84 W 490 V �\,\\241.81' \ \ S 88 W F.F. 498.0 �`` \N \ S 13 W \ \ \\\ 36-98' 10 F.F. 497.0 N 7 LA 3 AY BALE EAdH SIDE, L F E STI DIRECT/ UN- FF OV TOP, XISTING W)Z �iow �� \ v v � g � I / / �� 4" vertical Pace F.F. 497.8 F.F. 497.0 EMBEDDING DETAIL fi� stake ti \ \ \ � � � � � °e o�` y ' � / % /� � � / U'lle Ai IAL Z �/ IZ 0 FILL NOTE NO ALL FILL AREAS ARE COMPACTED TO 95 PERCENT STANDARD PROCTOR. C-1 L �2 160.70' S 84� Wire or nylon bound 1-iies 111"Ced on the � collLom 2 re-bars. steel pickets, or 2"X2'* sthkes 1 1/2' to 2' in eround ANCHORING DETAIL HAY BALE DIKE KY-13. OVERFLOW CHANNEL SECTION BETWEE14 LOTS 6 & 7 N. `T-S- 89 E 35.53' I 9 roc El / \ FINISHED PAD " T'.5. "P LOTS 1 THROUGH11 ( GRADE TO CREEK 1 3 13 fiWaSKIN REVISED 08/11/92 EROSION CONTROL LOCATIONS SHOWN REVISED 11/22191 TOE OF SLOPE SHOWN WITH SLOPE PROTECTION NOTE REVISED 11/27/91 REVISED F.P. ELEV, AND LOT CORNERS ELEVATIONS BIG CEDAR ADDITION COPPELL, TEXAS =0 "AS BUILT" GOO DWIN z 08/20/92 i MARSHALLuE CIVIL ENGINEERS - PLANNERS - SURVEYORS 16-FOOT DRAINAGE EASEMENT LOT 7 4 %I nnrl %/fY# APPENDIX A Conditional LOMR and Fill Certification read engineering OEOTECHNIC~/CONSULTANT~ Auqust 24, 1992 Project No. 824.1 Matthews Investments Sou~hwes=, Inc. 5220 Sprinq Valley Road, Suits 500 Dallas, Texas ?5240 ATTN= Mr. Tim House Construction Materials Testing Big'Cedar Addition Harris Road Coppell, Texas Gen=lemen: a eriodic basis to A representative of our firmwae present on P . observe and test the fill placed within =he residential bu~ldin9 pads at the referenced lite. The fill was placed in lifts by the contractor and tested by our firm in accordance with the earthwork recommendations in our geotechnical report, dated June 30, 1992. All site grading is now complete for this project. Based on the compaction test results, fills were compacted to a minimum of of Standard Proctor density (AiTM D-698). Sincerely, THE REED ENGINEERING GROUP MDS/RFR/wde copies submitted: (2) Matthews Investments Southwest, Inc./ Mr. Tim House (1) Goodwin & Marshall, In~./ Mr. D. Matthew Goodwin, P.E. 24,24b"I'1JTZORIVE "" SUI;FE400 · DAI"~TEXA~?5~35 · 214/3$0-~800 · (FAX}214/3~4)-0019 Federal Emergency Management Agency Washington, D.C. 20472 NOV I 8 1991 The Honorable Hark Wolfe Hayor of the City of Coppel! P.O. Box ~78 Coppell, Texas 75019 Dear Hayor Wolfe: Case No.: 91-06-70R ComauniCy: City of Coppell, Dallas and Denton Counties, Texas Com~mi=7 No.: 680170 This is in reference to a September 9, 1991, letter from Hs. H. Shohre Daneshmand, P.E., Acting Coppell CiTy Engineer, requesting that ~he Federal Emergency Hanagement Agency (FEHA) issue a conditional Let=er of Hap Revision (LOHR) for a proposed fill projectadjacen= to Tributary G-1 of Grapevine Creek. The proposed project involves =he placement of fill in.~he north overbank of Tributary G-1 of Grapevine Creek from approximately 685 feet upstream of Bethel School' Road to approximately 1,800 feet upstream of Bethel School Road. The fill is go be located within ~he floodway fringe, except in the area approximately 1,500 feet upstream of Bethel School Road, where =he fill w~ll encroach upon =he floodway by approximately 10 feet. In support of her request, Goodwin & Harshall, Inc., submitted an Au~ust 1991 report it prepared, entitled Floodplain Analvs~s for a portion of Tributary G-1 o~ Graoevine Creek. C~=7_ of CoDDell. Dallas Coun=7, Texas. This report contained =he following data: a written description of the proposed project and engineering methodology; HEC-lhydrologic models for the 10-, 50-, 100-, and 500-year floods for Tributary G-1 of Grapevine Creek watershed representing existing conditions, dated June 1991; HEC-2 hydraulic backwater models for =he 10-, 50-, 100-, and 500- year floods and floodway for Tributary G-1 of Grapevine Creek representing existing and proposed condtgions, dated August 1991; plo=red cross sections and water-surface profEles for Tribucary G-1 of Grapevine Creek through =he project area.; a topographic map delineating =he watershed of Tributary G-1 of Grapevine Creek; and topographic maps depicting 100- and 500-year floodplains and floodway for Tributary G-1 of Grapevine Creek,'representing existing and proposed conditions. 2 [n response to several telephone conversations w£th our technical evaluation contractor, Hr. D. Hatr/~ew Goodwin, P.E., o£ Goodwtn and Harshall, Inc., submitted several additional items supportins this conditional LOHErequest. These items include the followinS data: A completed "Certification of Fill Compaction' form, dated October 10, 1991, to address the requirements of Subparagraph 65.5(a)(6) of the National Flood Insurance Ih:osram (NFIP) re~ula- tions, and an October Il, 1991, letter statin~ that stone rtprap is not warranted for the fill slopes exposed to moving floodwaters. The letter further states that the developer of this project is forming a homeowners' association, whichwillbe responsible for periodic inspection of the fill slopes and, if failures are determined, for. restoration of the fill slopes to their orisinal condition. An October 1~; 1991, letter statin~ that all elevations in the submitted technical data are referenced to the Natienal Geodetic Vertical Datum of 1929. An October la, 1991, letter statin~ that the developer of this project is the current owner of both sides of Tributmry G-i of Grapevine Creek through HEC-2 station 3125, All data necessary to complete this conditional LO~ request were received by October 1~, 1991. Fees necessary to process chis case (a total of $663.00) have been receivedl Currently, we are preparinS a preliminary revised Flood Insurance Study (FIS) andFlood Insurance Rate Map (FIRM) for the City of Coppell to reflect a comprehensive rest~tdy of all streams, prepared by Ktmley-HornAssociates, Inc., and Horrison HydroloKy/Ensineerins, Inc. As par~ of the restudy, Tributary G-1 of Grapevine Creek is shown as an approximate 100-year flood- plain. We have reviewed the HEC-1 and HEC-2 models for Tributary G-1 of Grapevine Creek representing existing conditions contained in the submitted report and found that this information accurately depicts existing conditions for Tributary G-1 of Grapevine Creek. Thus, this information (includtn~ changed floodplain boundaries and established flood elevations) will be incorporated into the preliminary revised FIS and FIRM, whichwill be sent to your community in November 1991. Your cona~unity should reasonably use the existing conditions models as best available data for floodplain management purposes in accordance with NFIP regulations Subparagraph 60.3C0)(~). We have reviewed the submitted technical information and determined that the proposed project meets the minimum floodplain management criteria of the NFIP. If ~hts project is completed as proposed, a revision to the flood hazard infozmation for Tributary G-1 of Grapevine Creek to be-shown of the pre- limtnary revised FIRM would be warranted. This revision would depict reduced 100- and 500-year floodplains on the north bAnk through the project area, as 3 well as both increases and decreases in the 100-year water-surface elevations. The increases would range from 0.01 to 0.56 foot and would be located only on the developer's property. As stated in the submitted report, no existing structures are located in the existing or proposed 100-year floodplain. This determination is based on the 100-year flood discharges computed in the submitted report, and does not consider subsequent changes in watershed characteristics that would tend to increase flood discharges. The development of this project and other projects upstream could result in increased flood discharges, which, in turn, could result in increased 100-year flood eleva-. tions. FuTure restudies of your community's flood hazards would take into account the cumulative effects of development on flood discharges and could, therefore, establish higher 100-year flood elevations in this area. This conditional LOMR is based on minimum floodplain management crItkrta established under the NFIP. Your community is responsible for approving all proposed floodplain development, including the project upon which this request is based, and for ensuring that permits required by Federal or State law have been received. State and community officials, based on knowledge of local conditions and in the interest of safety, may set higher standards for construction or may limit development in floodplain areas. If the State of Texas or the CiTy of Coppellhas adopted more restrictive or comprehensive floodplain management criteria, those criteria take .precedence over the minimum NFIP requirements. Once this project is complete, your community should request a revision to the FIS and FIRM. This revision request must include the following data: Evidence of compliance with NFIP regulations Paragraph 65.~(b), which states that =all requests for changes to effective maps must be made in writing by the community's Chief Executive Officer (CEO) or an official designated by the CEO. Should the CEO refuse to submit such a request on behalf of another party, FEHA will agree to review it only if written evidence is provided indicating the CEO or designee has been requested to do so." Revised hydraulic analyses and floodplain mapping,'if the built' condition differs from the proposed condition. "As-bull=" certification by a registered professional engineer that the fill associated with this project has been placed in compliance with Subparagraph 65.5(a)(6) of =he NFIP regulations. "As-built" plans of the fill project certified by a registered professional engineer. Upon receipt of items I through ~ above, a revision to the City of Coppell FIS and FIRM will be initiated. If we are still processing the preliminary revised FIS and FIRM as discussed previously, we may be able =o incorporate The aforementioned changes into chac revision. If our processing of The current revision is complete, a separate revision will be initiated ~o reflec= The completed project. %/e have enclosed a copy of Par= 65 of =he NFIP regulations, which further describes =he netware and ex=enO of =he material needed =o support & request co revise =he FIS and FIRH. Compliance wiTh =he criteria oucltnec[ in =his documen= will exped/te FEHA's review process, Thus allowing =he effective FIS and FIPJ( for your community to be revised as appropriate, in a timely manner. Should you have any ques=tons regard/ng =his mac=er, please do no= hesi=a=e =o contac= =he Chief, Natural and Technological Hazards Division of FEHA in Den=on, Texas, a= (817) 898-5127 or Hacchew B. Miller o£ our Headquar=ers s=aff in ~ashing=on, D.C., a= (202) 646-3~61. Sincerely, ~illiamR. Locke Chief, Risk Studies Division Federal Insurance Administration Enclosure Hs. H. Shohre. Daneshmand, P.E. Hr. D. ~at-Thew Goodwin, P.E. Hr. Ronald ~. Morrtson, P.E., Morrison Hydrology/Engineering, Inc. APPENDIX B TRIBUTARY G-1 FINAL "AS BUILT" CONDITIONS HYDRAULIC MODEL AND RESULTS 0~0 0 ~00 00000 000~0 0 0~0 ~0~ ~ ~0 ~0~ ~0~ ~ ~ ~ ,00 ~ ,00 ~ o00 ~ ,00 ~00 ~00 ~00 ~00 0 .00 0 .00 0 .00 · 0 · · 8 ~ c; CI ?..) O~ 0 ,00 '9.099 ffi *00 ~ *00 0 ,00 ~ ,fflo ~ 0 ,0~ ~ 9o~ ~0 *~ · ~ ' .~ ~ 9°9~ ~ 0 00~ ~,~ ~0 ~ O~ ..o.~. 909o. 0 ,00 ~ *00 0 ,00 ,~0 ,~0 ,~0 ~ ~ ~ ,~0 ~ ~ o~o ~ ~ ~o~ ~ ~0~o ~ ~ .o. ~ .~. ~ .o. ~ ~ooo ~oo0 ~ o ~ o ~ ~ o ~.~ ~ oooo oooo ~ n ~ -~- oooo oooo eeee eeee 0 ~ ~o ~ oooo o0oo ~ ~ ~ 0000 0000 ~ ~ ............ ~ oooo oooo oooo ~ oooo oooo oooo eeee eeee eeee eeee ~00 ~0o 0000 0000 0000 0000 0000 ~ 0000 0000 0000 0000 0000 0000 0000 ~ 0~00 0~00 0~00 0~00 0~00 0~00 0~00 ~ ~ 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 ~ ~ ~ oooo oooo oooo oooo oooo oooo oooo E~ I ~ 0000 0000 0~ 0000 0000 ~m~ 0000 0000 0000 O~m 0000 0000 ~m 0000 0000 0000 0000 0000 0000 0000 0000 ~ ~ 0000 0000 0000 0000 0000 0000 0000 ~ ~ ........ 4444 ................ ~ ~ 0000 0000 0000 0000 ~ 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 Ieee 0000 0000 0000 0000 0000 0000 0000 0000 ieee ieee ieee Ieee oooo oooo 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 oooo o000 0000 o000 0000 oooo Ieee Ieee ieee 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 Ieee ee~e eee~ eee~ ieee Ieee 0000 0000 0000 0000 0000 0000 0000 0000 ~00 0000 ~ .... 444~ J44J .... 4~J .... 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 ~0~ ~0~ eeee ~o ~o oooo oo0o oo0o oooo 00oo ieee ~o~ ~o00 o0o0 o000 o0oo oooo ooo0 ~ II II II II II II II II II II ~ II II ~ II II II II fl II II II II II II # II II II # II II II ~ II II II # # II II II II ~ 0000000 000000 000 000000000000 0000 0000 0000 0 O0 ~ 0000000 000000 000 000000000000 0000 0000 0000 0 O0 0000000 000000 000 000000000000 0000 0000 0000 0 O0 eee eeeeeeeeeeee eele · go g ooo O0 0000 0000 000 0 0 O0 0000 0000 000 0 0 O0 0000 0000 000 0 0 ~ ~ ......... APPENDIX C TRIBUTARY G-1 FINAL "AS BUILT" CONDITIONS HYDRAULIC MODEL AND RESULTS ~ 0 O~m 00~0 Om~O 0 ~00 00000 ~ 0~ ~0~ ~ ~0 ~0~ O~ ~0~ ~0~ 0~ ~ 000~0 ~0~ ~0~ ~000~0 ~000~0 0 0 00~00 ~ ~0 *0 ~0000 O00~ C¢ * I~ 0 0 * ~ * ~t 0 ,-I * ~ .00 0 .00 ~0 .00 ~4~ .00 II ~ ~P'~ 0 0 II ,-I ¢'¢ 0 0 ~"~ O0 0 0 *~0 · *~1'0 · ,,~1'0 · ,~'l,O · 0 · 0 ,-I · ¢~1 · ,-I * I.-I I.-I ~ *00 O~ .00 ~1' .~0 0 .00 e-¢ ~' ~ ~00 i' i'° o. . I~ O0 *.cF * * ~.l~l~ n o .o,~ ,~o.~o .~ ~ qo~ ~ ~o~ ~ ~_ -;'°° 0 ,00 ~ ,00 0 .00 qo~ ~oo II ~ ,00 ~ ~ ,00 ~ ,0~ .oo .oo m ~ ~ ~m°°o~mo'm · ~~o~ .o. , ~ .~ · , ~ .~ . ~ .~ . ~ ~0~0 ~~0 ~0~0 o ooo~ ~..oom'~ I-I I eeleeeeeeeeeeeeeeeee®leeeeeelee®eeeleel®eee®®®eeeee eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee®eeeeeeeeeee~ eleeeeeeeeeeeeeeeeeeeeeeeee~eeeeeeeeeeeeeeeeeeeeeee eeeeee®e®~eee®eeeeeeeeeeeeeeeeee~eeeee®eeee®eeeeee~ eleee®eeee®eleeeeeeeeeeeeeeeeeeeaeeeeeeeeeeeeeeeeee eeeeeeeeeeeeeeeeeeeeeeeeeee~eeeeeeeeeeeeeeeeeeeeeee eeeeeeeeeee~eeeeeeeee~~~~~e®eeeeeeeee~ ~0~0~0~0~0~0~0~0 O0 0 0 ~ 0 O0 u 0 0 0 0 0 0 0 0 j j ~ c; leeeeeeeeeeeeleeeeeeel®eeeeee®eeeee®®leeeeleeee®lele®ee®ee®e"ee eeeeeeeeeee~eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee le®eee®leeeee~eee®ee®eeeeeeeeeeeeeeeeeeeeeeeeeeeee~ee®®ee®e®eee eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee eeeeeee®eeeeeeeeee®ee®eeeeeeee®eee~eeeeeeeeeeeeeeeee®e®eeeeeeee eeeeleeeeeeeeeeeeeeea®eeeee~eeee~e~e~eeeeeeeeeeeeee®®eeeee®eeee eeeeeeeee~eeeeeeee~eeeeeeeeeeeeeeeeeaeeeeeeee~eeeeeeeeeeeeeeeee eee eeeeeeeeeeeeeeeeeeeee~eeeeeeeeeeeeeeeeeeee ~~00000~~~ 0 0 0 0 0 0 0 0 0 0 eeleeeleeeeeeeeeeeeeeeaeeeeeeeeeeeeeeeeeeeeeeee~eeeeeeeee eleeeeeeeeleee®l®ee®eeeeee®e~eae~ee®eeeee~eeeeeeeeeaeeeee eeeleeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee®ee®ee leeeeeeeeeseeeeeeeeeeeeeee~eeeeeeeeeeeeeeeeeseeeeeeeeeeee HHHHHHHHH HHHHHHHHHHHHHHH 0~0~0~0~0~0~0~0~0~0 0 0 0 0 0 0 ~,~ r,~ O0 O0 O0 ~0 ~0 O0 r,~O 000 ~0 ~00 ~ 0000 000~ O0 O0 ~0 ,~1% ~0 ¢~0 ~'-0 0~0 ~'~0 ~" ...... 4c; ~:c; o~, ,-I ,-I ,-I ,-I ,-I ,-t ,-I ,-I ,-I ,'4 ,--I ~-I ,-I ,--I ,-¢ ,-I ,-I ,--I ,-I ,-I ,-I ,-I ~ ~ O0 O0 ~0 ~0 ~0 O0 ~0 ~0 ~0 ~ ~ O0 O0 O0 ~ ~0 O0 ~0 ~0 ~0 ~ ~ oo oo oo oo ~ oo ~ ~ ~ ~ M O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 ee ee ee ee ee oe O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 ~ ~ O0 O0 O0 O0 ~ O0 ~ ~ ~ ~ O0 O0 ~ O0 O0 ~0 O0 O0 O0 O0 O0 ~ O0 O0 ~ O0 O0 ~ O0 O0 O0 O0 O0 ~ .... ~ .... ~j .......... O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 ~0 ~0 ~0 ~0 ~0 ~0 ~0 ~0 ~0 ~0 ~0 ~0 ~0 ~0 ~0 ~0 ~0 ~0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 ~ ~ 0000 0000 O0 000000 O0 0 O0 O0 O0 O0 O0 O0 0 ~ ~ 0000 0000 O0 000000 O0 0 O0 O0 O0 O0 O0 O0 0 ~ 0000 0000 O0 000000 O0 0 O0 O0 O0 O0 O0 O0 0 0 HHHH HH H H