HomeMy WebLinkAbout01-16-12 Drainage & Flooding Committee Meeting
MIKE MOSTEITCHUCK ENGELKEN
CHAIRMANMEMBER
MIKE CLAUSENJOHN ZEMANEK
VICE CHAIRMANMEMBER
DARYL LEONARD
ALTERNATE
CITY OF LA PORTE DRAINAGE AND FLOODINGCOMMITTEE
MEETING AGENDA
Notice is hereby given of a meeting of the Drainage and Flooding Committee of the City
Council of the City of La Porte, to be held January 16,2012,in the Council Chambers of
City Hall, 604 West Fairmont Parkway, La Porte, Texas,beginning at 5:00 p.m.to
considerthe following items of business.
1.
Call to order
2.
Consider approval of amended Minutes of the Drainage and Flooding Committee
Meeting held on December 5, 2011– S. Harris
3.
Receive Preliminary Engineering Design Report for Taylor Bayou– J. Garza
4.
Receive Preliminary Engineering Design Report for Battleground Estates – J.
Garza
5.
Discuss recommendations of staff for meeting with the Texas Energy Coalition
and its membership – J. Garza
6.
Set date for next Drainage and Flooding Committee Meeting
7. Committee Comments
– Matters appearing on agenda; Recognition of
community members, city employees, and upcoming events; Inquiry of staff
regarding specific factual information or existing policy
8. Executive Session
– The City of La Porte Drainage and Flooding Committee
reserves the right to meet in executive session on any agenda item should the
need arise and if authorized by the Texas Open Meetings Act, Title 5, Chapter
551, of the Texas Government Code.
9. Adjourn
In compliance with the Americans with Disabilities Act, the City of La Porte will
provide for reasonable accommodations for persons attending public meetings.
To better serve attendees, requests should be received 24 hours prior to the
meetings. Please contact Patrice Fogarty, City Secretary, at 281.470.5019.
CERTIFICATION
I certify that a copy of the January 16,2012, agenda of items to be considered by the Drainage
and Flooding Committee was placed on the City Hall Bulletin Board onJanuary 12, 2012
_________________________________
Sharon Harris, Assistant City Secretary
I certify that the attached notice and agenda of items to be considered by the Drainage and
Flooding Committee was removed by me from the City Hall Bulletin Board on the ___ day of
______________, 2012
Name: ___________________________Title: _____________________
MIKE MOSTEIT, CHAIRMAN
JOHN ZEMANEK, MEMBER
Councilmember District 1
Councilmember At-Large A
MIKE CLAUSEN, VICE CHAIRMANCHUCK ENGELKEN, MEMBER
Councilmember District 6Councilmember District 2
DARYL LEONARD, ALT. MEMBER
CouncilmemberDistrict 3
MINUTES OF DRAINAGE AND FLOODING COMMITTEE
December 5,2011
The Drainage and Flooding Committeeof the City of La Portemet on Monday,December 5,2011,at the City Hall Council
Chambers, 604 West Fairmont Parkway, La Porte, Texas, at 5:00p.m.to consider the followingitems of business:
1. Call to Order
Chairman Mike Mosteitcalled the meeting to order at 5:03 p.m. Members of the Drainage and Flooding Committee
present: Chairman Mike Mosteit and Committee Members Chuck Engelken, JohnZemanekand Alternate Member Daryl
Leonard.Councilmember Dottie Kaminski was also present at the meeting. Absent:Vice Chairman Mike Clausen.
Members of City Executive Staff and City Employees Present:
City Manager’s Office: Steve Gillettand Traci Leach
City Secretary’s Office: Sharon Harris
PlanningDepartment:Tim Tietjens,Julian Garza and Brian Sterling
Public Works Department: Dave Mick
2.Consider approval of amended Minutes of the Drainage and Flooding Committee Meeting held onJuly 11, 2011
and Minutes of the Drainage and Flooding Committee Meeting held on August 4, 2011 –S. Harris
Alternate Committee Member Leonardmoved to approve the minutes as presented. Committee member Zemanek
seconded.MOTION PASSED.
Ayes:ChairmanMosteit, Committee members Engelken,Zemanek and Alternate
Member Leonard
Nays: None
Absent: Vice Chairman Mike Clausen
3.Receive presentation by Texas Energy Coalition or its membership regarding regulatory framework of pipeline
industry and discuss areas of concern regarding pipeline/drainage conflicts – T. Tietjens
Planning Director Tim Tietjensinformed the Drainage and Flooding Committee Members the Texas Energy Coalition and
its membership were present to address concerns of existing pipelines, the ability to perform drainage projects due to
pipelines and construction practices.
Chairman Mosteit requested the Texas Energy Coalition to offer solutions and improvements for De-silting projects in
addition to protecting homes and pipelines during heavy rainfall.
Alternate Committee Member Leonard questioned if adding new pipelines across current drainage areas couldcreate
issues or restrict drainage.
Chairman Mosteit commented arecent ordinance had been adopted addressing the depth of new pipelinesand not
restrictingthe flow of drainageand prior ordinances were to protect pipelines. Chairman Mosteit also commented pipeline
corridors are hindering improvements of drainage projectsin the community.
Page 1 of 2
December 5, 2011, Drainage and Flooding Committee Minutes
Planning Director,Tim Tietjens added the F101 Project was being affected by pipeline corridorsand requested solutions
to resolve current issues.
Haskel Rogers withExxonMobil advisedExxonMobil owned the majority of the pipelines in the areas of concern. Mr.
Rogers advised the committee,when new pipelines are constructed across flood control ditches or rivers, ExxonMobil
verifieswith the governing authorities and construct pipelines to accommodate current and future plans.Mr. Rogers
informed pipelines insideF101 date back to the1930’sand understands there is an issue with flood controland
ExxonMobil is willing to work with the city to resolve concerns.
Mr. Rogers requested clarification of the cause of flooding along the pipelines corridors from the committee. Chairman
Mosteit responded committee members were informed ditches could not be excavated low enough to continue drainage
flow downhill. Mr. Rogers informed a City of La Porte drawing had been received showing ten general areas of drainage
concerns. Mr. Rogers advised drawings with specific detailed plans are required from the city to determine if the areas of
concerns have pipelines involved. Mr. Rogers informedpipelines thatare required to be taken out of service havea
process and efforts would have to be coordinated between thecity and ExxonMobil.
Chairman Mosteit directed staff to meet and work with ExxonMobilto resolve areas of concern regarding
pipeline/drainage conflictsand to notifying at least onecommittee member toalso attend future meetings with theTexas
Energy Coalition and/or its membership.
4.Set date for next Drainage and Flooding Committee Meeting
Chairman Mosteit set the next Drainage and Flooding Committee Meeting for January 16, 2012 at 5:00 p.m.
5.Committee Comments
Chairman Mosteit, Committee member Engelken and Alternate member Leonard thanked the Texas Energy Coalition or
its membership for attending the meeting and explaining the processes for working with the city to resolve drainage
conflicts.
6.Executive Session
There was no executive session.
7.Adjourn
There being no further business, Alternate Member Leonardmoved to adjourn the meeting. Committee Member
Engelkenseconded.Motion Passed.
Meeting was adjourned at 5: 43 p.m.
Respectfully submitted,
__________________________________
Sharon Harris, Assistant City Secretary
Passed and approved on this 16
day of January 2012.
th
__________________________________
Chairman Mike Mosteit
Page 2 of 2
December 5, 2011, Drainage and Flooding Committee Minutes
REQUEST FOR DRAINAGE COMMITTEE AGENDA ITEM
Appropriation
Agenda Date Requested:January 16, 2012
:N/A
Source of Funds
Julian Garza
Requested By:
Account Number:N/A
Department: Planning
Amount Budgeted:N/A
Report: _X_Resolution: _ _Ordinance: ___
Amount Requested: N/A
Budgeted Item: XYES NO
Exhibit: Hydrologic and Hydraulic Study for Taylor
Bayou
SUMMARY
On September 12, 2011, City Council Authorized Civil Tech Engineering, Inc. to proceed with the Taylor
Bayou Preliminary Engineering Design Report. The scope of work was defined in tasks to limit the scope
as needed. The results of the Hydrologic and Hydraulic study consist of Task 1 through 4 of the
Engineering Design Report proposal. These tasks were performed to evaluate the capacity of Taylor
Bayou and determine if structural flooding could be reduced by improving conveyance of Taylor Bayou.
It was determined that the 10-, 50- and 100-year water surface elevations of Taylor Bayou only cause
minor street flooding in the Shady River Subdivision and historical structural flooding in the subdivision
is likely caused by coastal storm surges in Galveston Bay.
The study did however indicate significant head losses at McCabe Roadand Taylor Bayou and
recommends replacement of existing culverts to eliminate the out-of-bank flooding upstream of McCabe
Road during extreme events.
Due to the status of development in the area this is not an urgent and does not require immediate
attention. Therefore, staff will work with Harris County and Harris County Flood Control in an effort to
partner on this project.
Action Required:
Present Taylor Bayou Preliminary Engineering Report findings.
Approved for Drainage Committee Agenda
___________________________________________________________
Steve Gillett, Interim City Manager Date
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Civil EEngineering
Wateer Resources
Transsportation
Strucctures
Economic Analysis
TTECHNICAALMEMORANDUMM
TO:JulianGarza,P.E.,CCityofLaPortte
MelvinnSpinks,P.E.,,CivilTechEngineering,Incc.
CC:
MM:AshishhWaghray,P.E.,CivilTechEEngineering,Inc.
FRO
12/13/11
DATE:Decemmber13,20111
RE:HydrologicandHyddraulicStudyforTaylorBayou,HCFCUnnitA10400000
CityoffLaPorteDraainageProjecttNo.19,LaPPorte,Texas
Thisttechnicalmeemorandumpresentstheestudyfindiingsforhydrologicandhydraulicannalysis
performedforTayylorBayou,HHCFCUnitA1040000,annditstributarryHCFCUnitA1041201..The
hydroologicandhydraulicanalyysiswasperfoormedforthee10,50,1000and500yearstormeevents
assocaainfalloverttheTaylorBaayouwatershhed.Thesstudyresultsarepresenttedto
iatedwithr
determinewhetheertherecommmendeddraainageimproovementsaloongHCFCUnnitA1040000as
identiifiedintheCCityofLaPorteCityWideeDrainageSStudywouldeliminateoutofbankfloooding
alongTaylorBayouu,HCFCUnitAA1040000,iintheShadyRiverSubdivision.
StudyyBackgroundd
SeverralhomesintheShadyRRiverSubdivissionarelisteddasrepetitivvefloodlossspropertiesiinthe
FEMAANationalFlooodInsuranceeProgram(NFFIP).TheShaadyRiverSubdivisionisloccatedintheCCityof
LaPoortebordereddontheeasttbyTaylorBaayou,HCFCUUnitA10400000,andonthewestby
HCFC
UnitAA1041201.TheprojectlocationisshhowninExhibbit1.TheCiityofLaPorttecommissioneda
compprehensivedrrainagestudyyentitledCittyofLaPorteeCityWideDrainageStuudy(CWDS)dated
Januaary,2009,preeparedbyKlootzAssociatess,Inc.TheCWWDSrecommmendedchannelimprovemments
alongTaylorBayoou,HCFCUnnitA10400000,beginninggapproximaately600feeetdownstreaamof
McCabeRoadtoittscorporateccitylimits,alengthofapproximately1,,608feet.ThheCWDSidenntified
thattthesechanneelimprovemeentswouldelliminateoutofbankflooddingalongTaaylorBayouiinthe
ShadyyRiverSubdivvisionduringa100yearsttormevent.
Adettailedhydroloogicandhyddraulicanalyssiswasrecommmendedfoorprojectdeevelopmentto:(1)
updattethewatersshedhydrologyconsiderinngnewresideentialandcoommercialdevelopmentsiinthe
Q:\2011\\310017\Report\Letteer Report_12-13-2011.docx
+RRXVWRQ7HOJHH5RDG&\SUHVV7H[[DV 7HO )D[
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TechnicalMemorandum:Hydrologic&HydraulicStudyforTaylorBayou,HCFCUnitA1040000
December13,2011
Page2of6
upperTaylorBayouwatershed;(2)developahydraulicmodelforHCFCUnitA1040000fromits
studylimitstoSH146;(3)determinethelimitsandsizeoftheproposedchannelimprovementsto
hydraulicallyconveya100yeardesignstormwithinchannelbanks;and,(4)locateandhydraulically
sizeamitigationpondvolumeandcontrolstructuretomitigateanydownstreamadverseimpacts
fromtheproposedchannelimprovements.
ScopeofWork
CivilTechEngineering,Inc.enteredintoanAgreementforProfessionalEngineeringServiceswiththe
CityofLaPorte,TexasonSeptember13,2011.Thedetailedscopeofworkisprovidedin
Attachment1oftheAgreement.Thescopeofworkincludesthefollowingtasks:
Task1:ProjectCoordinationandMeeting
Task2:DataCollectionandReview
Task3:HydrologicAnalysis
Task4:HydraulicAnalysis
Task5:MitigationAnalysis
Task6:ProjectEvaluation
Task7:StudyReport
ThescopeofworkalsoincludessurveyingservicesforHCFCUnitA1040000andHCFCUnitA104
1201.SurveyingservicesarebeingprovidedbyCivilConcepts,Inc.TheCityofLaPortehasonly
authorizedTask1throughTask4andthesurveyingservices.Task5throughTask7willbe
authorizedpendingtherecommendationsinthistechnicalmemorandum.
SpecialFloodHazardAreas
TheShadyRiverSubdivisionislocatedentirelyintheFEMAregulatoryfloodplain,ZoneAE,asshown
intheFEMAFloodInsuranceRateMap(FIRM),MapNumbers48201C0945Land48201C1085L,
datedJune18,2007.TheFEMAFIRMisshowninExhibit2.ZoneAErepresentsareassubjectto
inundationbythe1%annualfloodevent(100year)withBaseFloodElevations(BFEs)determined
bydetailedmethods.ABFEof11feetisshownontheFEMAFIRMfortheShadyRiverSubdivision.
TheBFEwasdeterminedbasedoncoastalstormsurgemodelingforGalvestonBay.TheFEMAFlood
InsuranceStudy(FIS)listedthefollowingcoastalstormsurgeelevationsintheTaylorBayou
Watershed:
10%(10Year)BFE=4.8feet
2%(50Year)BFE=9.6feet
1%(100Year)BFE=11.4feet
TechnicalMemorandum:Hydrologic&HydraulicStudyforTaylorBayou,HCFCUnitA1040000
December13,2011
Page3of6
TaylorBayouanditstributariesaretidallyinfluencedwithoverbankareassubjecttoinundation
fromcoastalstormsurgesinGalvestonBay.TheShadyRiverSubdivisionwasconstructedinthemid
ϭϵϲϬ͛ƐpriortotheNationalFloodInsuranceProgram(NFIP)andtheavailabilityoffloodplainmaps
andflooddata.Basedonexistingtopography,thesubdivisionissusceptibletoinundationfrom
tropicalstormsproducingsurgeelevationsabove7feet.Itislikelythathomesconstructedinthe
ϭϵϲϬ͛ƐandϭϵϳϬ͛Ɛwouldbesusceptibletofloodinundationfromcoastalstormflooding.
FEMAEffectiveModels
TaylorBayou,HCFCUnitA1040000,isaFEMAstudiedstream.ThestudylimitsalongHCFCUnit
A1040000extendfromitsconfluencewithClearCreek,HCFCUnitA1000000,tojustupstreamof
ShoreacresBoulevard.TheFEMAeffectivehydrologic(HECHMS)modelandhydraulic(HECRAS)
modelforTaylorBayouwereobtainedfromtheHarrisCountyFloodControlDistrict.TheFEMA
effectivemodelsservedasthebaseconditionmodelsforthisstudy.
ItistheintentofthisstudytoextendtheFEMAeffectivehydraulic(HECRAS)modelforTaylor
Bayou,HCFCUnitA1040000,fromShoreacresBoulevardupstreamtoStateHighway146.In
addition,anewhydraulicmodelwasdevelopedforHCFCUnitA1041201fromitsconfluencewith
HCFCUnitA1040000toBayForestGolfCourse.ThestudylimitsarelocatedinSubareaA104A
(1998.72acres)oftheTaylorBayouwatershed.TheFEMAeffectivehydrologic(HECHMS)model
computedpeakflowsforthe10,50and100yearstormeventsforSubareaA104Aaslistedin
Table1.
Table1.FEMAEffectiveHECHMSModelforSubareaA104A
DrainageDAPeakFlow(cfs)
Subarea(acres)10Year50Year100Year
A104A1998.7293014231681
RevisedHydrologic(HECHMS)Model
SubareaA104Awassubdividedintonine(9)subareas,identifiedasA104A1throughA104A9,to
computepeakflowsalongHCFCUnitA1040000andHCFCUnitA1041201.Therevised
watershedmapforSubareaA104AisshowninExhibit3.SubareasA104A1,A104A2,A104A3,
A104A4andA104A9weredelineatedforcontributingdrainageareastoTaylorBayou,HCFCUnit
A1040000.SubareasA104A5,A104A6,A104A7andA104A8weredelineatedforcontributing
drainageareastoHCFCUnitA1041201.ThehydrologiccomputationalnodesalongHCFCUnit
A1040000andHCFCUnitA1041201areshoweexhibit.TherevisedHECHMSmodel
ninth
resultsforTaylorBayou,HCFCUnitA1040000,arelistedinTable2.
TechnicalMemorandum:Hydrologic&HydraulicStudyforTaylorBayou,HCFCUnitA1040000
December13,2011
Page4of6
Table2.RevisedHECHMSModelPeakFlowsalongTaylorBayou,HCFCUnitA1040000
DrainageLocation/DAPeakFlow(cfs)
Area/NodeDescription(acres)10Year50Year100Year
A104ASubareaUpstreamofSH146491.07351518605
A104A1UpstreamofSH146491.07351518605
A104A2FutureLakesatFairmontGreens231.25143213249
A104A2USofMcCabeRoad704.32491726849
A104A3SubareaWestofShadyRiverSubdivision91.0777113132
A104A3AlongShadyRiverSubdivision795.39560830967
A104A4ShadyRiverSubdivision57.34104143163
A104A4TaylorBayou&HCFCUnit1041200confluence1332.16104015811864
A104A9SubareaDownstreamofConfluence660.166419211069
A1040000_236_JSH146NearPortRoad(Outfall)1992.32159323342760
Note:Shadedareasrepresentdrainagenodeswithcumulativedrainageareasandflowsfromallupstreamareas.
SubareaA10407encompassesthedrainagearealocatedeastofSouthBroadwayStreet.TheCityof
LaPorteconstructedstormdrainageandoutfallimprovementsinvarioussubdivisionstodrainflows
fora5yearstormeventtoGalvestonBay.Therevisedhydrologicmodelincludesadiversionroutine
forSubareaA104A7basedonthecomputed5yearpeakflowforSubareaA104A7of210cfs.The
revisedHECHMSmodelresultsforHCFCUnitA1041201arelistedinTable3.TheHECHMSmodel
outputsummaryisprovidedinAttachment1.
Table3.RevisedHECHMSModelResultsalongHCFCUnitA1041201
DrainageDAPeakFlow(cfs)
NodeDownstreamElement(acres)10Year50Year100Year
A104A5BayForestGolfCourse177.79229.3323.7373.5
A104A5DownstreamofGolfCourse177.79229324374
A104A6S.BroadwayStDrainageArea116.10119261299
A104A7DrainageAreaEasttoS.BroadwaySt125.76253345393
FlowsfromA104A7toA1041201
After5yearFlow(210cfs)44135183
DiversiontotheBay
A104A6AtBroadwayOutfall(NorthofShadyRiver)419.65443698832
A104A8ShadyRiverSubdivision59.78108148169
A104A4TaylorBayou&HCFCUnit1041200Confluence1332.16104015811864
Note:Shadedareasrepresentdrainagenodeswithcumulativedrainageareasandflowsfromallupstreamareas.
RevisedHydraulic(HECRAS)Model
FieldsurveyswereperformedtoobtainchannelcrosssectionsalongHCFCUnitA1040000and
HCFCUnitA1041201.Fourteen(14)surveyedcrosssectionswereobtainedalongHCFCUnitA104
0000.Eleven(11)surveyedcrosssectionswereobtainedalongHCFCUnitA1041201.The
surveyedcrosssectionlocationsareshowninExhibit3.TheFEMAeffectivehydraulic(HECRAS)
modelforTaylorBayou,HCFCUnitA1040000,wasextendedfromShoreacresBoulevardtoSH146.
Anewhydraulic(HECRAS)modelforHCFCUnitA1041201wasdevelopedfromitsconfluencewith
TechnicalMemorandum:Hydrologic&HydraulicStudyforTaylorBayou,HCFCUnitA1040000
December13,2011
Page5of6
TaylorBayou,HCFCUnitA1040000,totheBayForestGolfCourse.Topographicdataforoverbank
areaswereobtainedfromLiDARDEMdata.ExistingbridgesandculvertsalongHCFCUnitA10400
00andHCFCUnitA1041201weresurveyedandincludedintherevisedmodels.Theexisting
drainagestructuresarelistedinTable4.
Table4.ExistingDrainageStructures
ChannelRoadCrossingStructureTypeStructureDetails
TaylorBayou,HCFCUnitA1040000ShoreacresBlvdBridgeNoPiers
TaylorBayou,HCFCUnitA1040000McCabeRdCrossCulverts272"RCP
HCFCUnitA1041200ShadyRiverRdBridge218"Piers
HCFCUnitA1041201McCabeRdCrossCulverts272"RCP
Thecomputed10,50and100yearwatersurfaceelevationsalongTaylorBayou,HCFCUnitA104
0000,areprovidedinTable5.Thecomputed10,50and100yearwatersurfaceelevationsalong
HCFCUnitA1041201areprovidedinTable6.TheextentoffloodingalongTaylorBayou,HCFC
UnitA1040000,andHCFCUnitA1041201forthe10,50and100yearstormeventsisshownin
Exhibit4.TheHECRASmodelfloodprofilesandoutputresultsareprovidedinAttachment2.
Table5.RevisedHECRASModelResultsforTaylorBayou,HCFCUnitA1040000
RiverPeakFlow(cfs)WaterSurfaceElevation(feet)LowestGround
Station10Year50Year100Year10Year50Year100YearElevation(feet)*
316131040158118643.785.145.70
3211961290710513.865.225.78
3236359688310253.885.245.797.60
329355608309673.985.315.867.80
334855448069404.165.445.986.80
341325257799084.445.706.227.40
345525147618894.665.906.429.40
350904997408645.006.176.66
353144937318545.076.166.61
35363McCabeRoad
354294917268496.7810.1511.39
355404787088277.1610.5411.39
361834126097117.2610.5811.42
368683515186057.3510.6211.45
Note:TheshadedareasrepresentthecrosssectionsalongtheShadyRiversSubdivision.
*GroundelevationatastructurelocationestimatedbasedonLiDARDEMData.
TechnicalMemorandum:Hydrologic&HydraulicStudyforTaylorBayou,HCFCUnitA1040000
December13,2011
Page6of6
Table6.RevisedHECRASModelResultsforHCFCUnitA1041201
RiverPeakFlow(cfs)WaterSurfaceElevation(feet)LowestGround
Station10Year50Year100Year10Year50Year100YearElevation(feet)*
1875137829253.825.185.75
5405027689103.855.215.778.00
10254877518913.875.235.806.80
1072ShadyRiverRoad
10964857488883.965.466.167.30
16324697298674.005.496.197.50
21174557138484.045.526.227.50
25634436988325.016.106.66
30573565416386.137.047.45
3121McCabeRoad
31863365065957.008.959.20
35522864194897.179.029.26
40532293243747.459.109.35
Note:TheshadedareasrepresentthecrosssectionsalongtheShadyRiversSubdivision.
*GroundelevationatastructurelocationestimatedbasedonLiDARDEMData.
SummaryofResults
Thecomputed10,50and100yearwatersurfaceelevationsalongTaylorBayou,HCFCUnitA104
0000,andHCFCUnitA1041201likelycauseonlyminorstreetfloodingintheShadyRiver
Subdivision.Historicalstructuralfloodinginthesubdivisionwaslikelycausedfromcoastalstorm
surgesinGalvestonBay.Itwasbeyondthescopeofthisworktoinvestigateotherfloodingcauses
suchas:(1)undersizedstormsewerpipes,(2)inadequatesheetflowsystemforextremeevents,
and(3)stormsewerpipefailuresandmaintenanceneeds.Itisourprofessionalopinionthatthe
recommendedchannelimprovementsalongTaylorBayou,HCFCUnitA1040000,intheCWDS
wouldnotalleviatethehistoricalstructuralfloodingproblemsinthesubdivision.Nonstructural
measuressuchasstructureelevations,buyouts,orfloodinsurancearethelikelyfloodriskreduction
optionsforthesubdivision.
Thehydraulicresultsdidindicateasignificantheadlossof4.8feetduringa100yearstormevent
throughtheexisting272inchRCPsatMcCabeRoadandHCFCUnitA1040000.Wewould
recommendthereplacementoftheexistingculvertstoeliminatetheoutofbankfloodingupstream
ofMcCabeRoad.ThehydraulicanalysisalsofoundinsufficientchannelcapacityalongHCFCUnit
A1041201upstreamofMcCabeRoad.OutofbankfloodingwasidentifiedintheForestVista
MobileHomeParkfora10yearstormevent.Structuralsolutionscouldincludedetentionupstream
inthegolfcourseorchannelimprovementsalongHCFCUnitA1041201upstreamofMcCabeRoad.
y,//d^
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ATTACHMENT1
HECHMSMODELOUTPUTSUMMARY
TaylorBayouHEC-HMSModel
Project : ProjectA1000000
Basin Model : A104A_Div
Jan 04 11:56:48 CST 2012
HEC-HMS
A104A5A104A5
A104A1A104A1
#A5#A5
A104A2A104A2
A104A6A104A6
#A1#A1
A104_6A104_6
A104_4A104_4
#A2#A2
A104A7A104A7
#A6#A6
A104_3A104_3
A104A4A104A4
A104A8A104A8
A104_5A104_5
#A3#A3
5-Year A104A75-Year A104A7
A104A3A104A3
#A4-2#A4-2
#A4-1#A4-1
A104_2A104_2
#A4#A4
Galv BayGalv Bay
A104A9A104A9
A104_1A104_1
A1040000_0296_DA1040000_0296_D
HECHMSResults
HMSElementArea(acre)PeakFlow(cfs)
ElementDownstreamElement10Year50Year100Year500Year
A104A1#A1491.07350.8518.3605.2858.8
#A1A104_4350.8518.3605.2858.8
A104_4#A2349.7516.4602.9839.7
A104A2#A2213.248143.2213.1249.2355.7
#A2A104_3490.5726.4848.91174.6
A104_3#A3488.9725.3846.61169.3
A104A3#A391.07277112.9131.6184.5
#A3A104_2559.6829.9967.11323.2
A104_2#A42556.6827.8964.61315.7
A104A4#A4257.344103.9142.7163216.7
#A42#A4611.6906.610511389.4
A104A5#A5177.792229.3323.7373.5507.3
#A5A104_6229.3323.7373.5507.3
A104_6#A6229.3323.4373.4506.6
A104A6#A6116.096188.7260.8299.2399.8
A104A75YearA104A7125.76253.3344.9393.6518.6
5YearA104A7GalvBay209.5209.5209.5209.5
5YearA104A7#A643.8135.4184.1309.1
#A6A104_5442.7697.5831.81172.9.
A104_5#A41423.5662.2789.41129.9
A104A8#A4159.776107.5147.6168.9224.1
#A41#A4513.1781.5924.71314.5
#A4A104_11040.21580.81863.52597.2
A104_1A1040000_0296_D105015571838.62547.5
A104A9A1040000_0296_D660.16640.5921.31068.81480.3
A1040000_0296_D1592.52333.72760.43867.6
NodeGalvBayisthe5yearflowdiversionfromA104A7(209.5CFS)intoGalvestonBay
Q:\2011\310017\Calculations\HMSComparison.xlsx
&LYLO7HFK
0)+0''4+0)X
0%T
ATTACHMENT2
HECRASMODELFLOODPROFILESANDOUTPUTRESULTS
Elevation (ft)
Elevation (ft)
Elevation (ft)
HEC-RASOutputforA104-00-00
HEC-RAS Plan: FEMAeff0607r
ReachRiver StaQ TotalMin Ch ElW.S. ElevCrit W.S.E.G. ElevE.G. SlopeVel ChnlFlow AreaTop WidthFroude # Chl
(cfs)(ft)(ft)(ft)(ft)(ft/ft)(ft/s)(sq ft)(ft)
A104-00-00_00312970.9522078.00-12.560.90-8.720.920.0000611.191816.41378.700.08
A104-00-00_00312970.9525115.00-12.561.30-6.341.420.0003022.752001.96519.280.18
A104-00-00_00312970.9526532.00-12.561.45-5.491.630.0004603.442082.67575.880.22
A104-00-00_00312970.95210394.00-12.561.75-3.422.170.0010125.242288.60747.590.33
A104-00-00_00313011.3772078.00-12.560.90-8.720.930.0000671.421460.77405.410.09
A104-00-00_00313011.3775115.00-12.561.28-6.341.460.0003563.351542.24496.660.20
A104-00-00_00313011.3776532.00-12.561.42-5.491.700.0005524.211575.96528.260.25
A104-00-00_00313011.37710394.00-12.561.68-3.632.340.0012736.511658.93667.370.38
A104-00-00_00313043 Bridge
A104-00-00_00313074.8842078.00-12.560.92-8.720.960.0000661.431453.06169.420.09
A104-00-00_00313074.8845115.00-12.561.35-6.341.520.0003473.351526.24432.790.20
A104-00-00_00313074.8846532.00-12.561.53-5.501.800.0005314.201562.93527.760.25
A104-00-00_00313074.88410394.00-12.561.90-3.642.540.0011796.411682.16604.570.37
A104-00-00_00313237.4252078.00-12.560.940.960.0000691.351541.92203.190.09
A104-00-00_00313237.4255115.00-12.561.441.590.0003493.111646.32228.690.20
A104-00-00_00313237.4256532.00-12.561.671.900.0005253.851719.78431.390.24
A104-00-00_00313237.42510394.00-12.562.272.760.0010805.672069.60792.450.35
A104-00-00_00313430.3902078.00-14.700.950.970.0000651.311883.52895.080.08
A104-00-00_00313430.3905115.00-14.701.531.650.0002982.872405.07905.070.18
A104-00-00_00313430.3906532.00-14.701.821.990.0004223.462670.01910.100.21
A104-00-00_00313430.39010394.00-14.702.652.940.0007154.643454.53988.230.28
A104-00-00_00315194.9542078.00-4.301.00-3.631.010.0000100.385529.691158.150.03
A104-00-00_00315194.9545115.00-4.301.77-3.211.780.0000370.806423.621183.020.06
A104-00-00_00315194.9546532.00-4.302.15-3.052.160.0000490.956878.321212.100.07
A104-00-00_00315194.95410394.00-4.303.18-2.663.210.0000731.288130.451271.090.09
A104-00-00_00317544.6212200.00-5.801.021.020.0000050.287936.151552.100.02
A104-00-00_00317544.6215024.00-5.801.831.830.0000160.559192.501569.820.04
A104-00-00_00317544.6216340.00-5.802.232.230.0000200.659822.431578.630.05
A104-00-00_00317544.6219962.00-5.803.303.310.0000300.8611527.511604.710.06
A104-00-00_00318149.9932335.00-6.501.031.030.0000050.346893.781078.770.02
A104-00-00_00318149.9934929.00-6.501.831.840.0000160.637768.541090.090.04
A104-00-00_00318149.9936144.00-6.502.242.250.0000210.758208.521095.750.05
A104-00-00_00318149.9939524.00-6.503.313.330.0000331.019406.301151.650.06
A104-00-00_00319053.2342335.00-4.302.002.130.0023492.93797.24468.990.40
A104-00-00_00319053.2344929.00-4.302.923.160.0027483.921257.26540.560.45
A104-00-00_00319053.2346144.00-4.303.293.560.0027234.201461.68570.630.46
A104-00-00_00319053.2349524.00-4.304.264.600.0025594.632055.49656.170.46
A104-00-00_003110155.222427.00-5.102.35-1.202.360.0001060.852851.751154.040.09
A104-00-00_003110155.224870.00-5.103.45-0.333.480.0001411.214031.941247.040.11
A104-00-00_003110155.226021.00-5.103.89-0.113.910.0001511.344503.831436.980.12
A104-00-00_003110155.229254.00-5.104.930.434.970.0001661.616512.601910.860.13
A104-00-00_003111429.2 2427.00-6.282.37-5.242.370.0000040.347070.34944.390.02
A104-00-00_003111429.2 4870.00-6.283.50-4.783.500.0000110.608137.471031.820.04
A104-00-00_003111429.2 6021.00-6.283.94-4.603.950.0000150.708556.741056.730.04
A104-00-00_003111429.2 9254.00-6.285.01-4.155.030.0000250.979586.851150.110.05
A104-00-00_003113273.422578.00-6.412.382.390.0000080.445894.07824.550.03
A104-00-00_003113273.424777.00-6.413.533.540.0000170.706852.66844.480.04
A104-00-00_003113273.425833.00-6.413.983.990.0000210.817235.76864.970.05
A104-00-00_003113273.428843.00-6.415.075.090.0000321.088219.44939.140.06
A104-00-00_003114023.112578.00-4.082.40-2.452.400.0000200.554679.89963.410.04
A104-00-00_003114023.114777.00-4.083.55-2.013.560.0000350.826034.941451.170.06
A104-00-00_003114023.115833.00-4.084.01-1.864.020.0000410.936703.881553.760.06
A104-00-00_003114023.118843.00-4.085.11-1.455.130.0000541.198405.981736.970.08
A104-00-00_003114143.7 2578.00-4.082.40-2.452.410.0000200.574537.15889.420.04
A104-00-00_003114143.7 4777.00-4.083.56-2.013.570.0000360.865575.28927.690.06
A104-00-00_003114143.7 5833.00-4.084.02-1.864.030.0000430.975990.541127.130.07
A104-00-00_003114143.7 8843.00-4.085.11-1.465.140.0000601.266998.831748.750.08
A104-00-00_003114178 Bridge
A104-00-00_003114213.732578.00-4.082.42-2.452.430.0000200.574552.46889.650.04
A104-00-00_003114213.734777.00-4.083.59-2.013.600.0000360.855599.96930.180.06
A104-00-00_003114213.735833.00-4.084.03-1.864.040.0000430.975997.90970.090.07
HEC-RAS Plan: FEMAeff0607r (Continued)
ReachRiver StaQ TotalMin Ch ElW.S. ElevCrit W.S.E.G. ElevE.G. SlopeVel ChnlFlow AreaTop WidthFroude # Chl
(cfs)(ft)(ft)(ft)(ft)(ft/ft)(ft/s)(sq ft)(ft)
A104-00-00_003114213.738843.00-4.085.13-1.465.160.0000591.267017.401027.800.08
A104-00-00_003114249.682768.00-4.082.432.430.0000230.584801.161000.920.05
A104-00-00_003114249.684671.00-4.083.603.610.0000320.785986.761043.430.06
A104-00-00_003114249.685619.00-4.084.034.040.0000370.876447.471083.370.06
A104-00-00_003114249.688384.00-4.085.145.160.0000481.117684.041134.310.07
A104-00-00_003115331.722768.00-6.052.44-4.772.440.0000090.475909.73848.500.03
A104-00-00_003115331.724671.00-6.053.62-4.373.620.0000160.676921.88912.430.04
A104-00-00_003115331.725619.00-6.054.05-4.204.060.0000200.777309.041062.270.05
A104-00-00_003115331.728384.00-6.055.19-3.775.200.0000311.008363.451333.220.06
A104-00-00_003117007.192668.00-9.812.452.460.0000120.465787.481037.810.03
A104-00-00_003117007.194469.00-9.813.643.640.0000180.637110.231306.850.04
A104-00-00_003117007.195386.00-9.814.094.090.0000210.727705.521356.580.05
A104-00-00_003117007.198051.00-9.815.235.240.0000280.919766.382251.130.06
A104-00-00_003119325.731751.00-5.802.492.490.0000290.573091.62865.170.05
A104-00-00_003119325.732952.00-5.803.703.710.0000340.734591.971594.360.06
A104-00-00_003119325.733604.00-5.804.144.150.0000380.815343.471798.740.06
A104-00-00_003119325.735439.00-5.805.315.330.0000420.977932.872508.060.07
A104-00-00_003119419.131751.00-5.802.49-3.292.500.0000240.612872.69868.230.05
A104-00-00_003119419.132952.00-5.803.70-2.713.710.0000330.833611.221042.130.06
A104-00-00_003119419.133604.00-5.804.14-2.464.160.0000400.943882.651204.460.06
A104-00-00_003119419.135439.00-5.805.31-1.865.340.0000521.214596.781944.640.08
A104-00-00_003119441 Bridge
A104-00-00_003119464.87820.00-5.802.50-3.952.500.0000050.292873.55868.420.02
A104-00-00_003119464.871290.00-5.803.71-3.583.710.0000060.363611.651711.410.03
A104-00-00_003119464.871539.00-5.804.15-3.424.150.0000070.403882.682450.750.03
A104-00-00_003119464.872291.00-5.805.31-3.015.320.0000090.514594.662896.450.03
A104-00-00_003119486.95820.00-5.802.502.500.0000060.282922.99829.720.02
A104-00-00_003119486.951290.00-5.803.713.710.0000070.354204.321279.670.03
A104-00-00_003119486.951539.00-5.804.154.150.0000070.394829.551582.530.03
A104-00-00_003119486.952291.00-5.805.325.320.0000080.477759.103046.510.03
A104-00-00_003119534.55820.00-5.882.50-4.562.500.0000020.223795.55897.230.02
A104-00-00_003119534.551290.00-5.883.71-4.293.710.0000030.284552.031184.140.02
A104-00-00_003119534.551539.00-5.884.15-4.174.150.0000040.324831.811216.230.02
A104-00-00_003119534.552291.00-5.885.32-3.875.320.0000050.415572.951424.240.02
A104-00-00_003119566 Bridge
A104-00-00_003119598.26820.00-5.882.51-4.572.510.0000020.223799.56899.330.02
A104-00-00_003119598.261290.00-5.883.71-4.293.720.0000030.284555.631183.000.02
A104-00-00_003119598.261539.00-5.884.16-4.174.160.0000040.324835.021214.230.02
A104-00-00_003119598.262291.00-5.885.32-3.865.320.0000050.415575.901422.900.02
A104-00-00_003119618.56820.00-5.882.512.510.0000020.214045.221136.100.02
A104-00-00_003119618.561290.00-5.883.723.720.0000030.285553.901431.410.02
A104-00-00_003119618.561539.00-5.884.164.160.0000030.316198.491494.210.02
A104-00-00_003119618.562291.00-5.885.325.330.0000050.398323.262271.000.02
A104-00-00_003120816.67820.00-3.952.51-3.202.510.0000040.233503.651298.400.02
A104-00-00_003120816.671290.00-3.953.72-3.003.720.0000050.294496.841934.610.02
A104-00-00_003120816.671539.00-3.954.16-2.904.160.0000050.324923.192004.300.02
A104-00-00_003120816.672291.00-3.955.32-2.655.330.0000050.379064.872283.720.02
A104-00-00_003122407.37820.00-4.052.51-2.982.520.0000060.282927.641213.310.02
A104-00-00_003122407.371290.00-4.053.72-2.723.720.0000060.353708.711504.230.03
A104-00-00_003122407.371539.00-4.054.16-2.604.160.0000070.394050.741561.540.03
A104-00-00_003122407.372291.00-4.055.33-2.295.330.0000080.457510.601894.710.03
A104-00-00_003123133.07820.00-6.152.562.590.0001671.32823.66645.810.12
A104-00-00_003123133.071290.00-6.153.753.770.0001341.391797.861019.290.11
A104-00-00_003123133.071539.00-6.154.194.210.0001291.452277.231139.830.11
A104-00-00_003123133.072291.00-6.155.355.370.0001141.553712.161342.360.11
A104-00-00_003123216.1892.00-6.152.60-5.022.600.0000020.17535.35356.720.01
A104-00-00_003123216.18166.00-6.153.78-4.713.780.0000030.26642.29437.130.02
A104-00-00_003123216.18206.00-6.154.22-4.574.220.0000040.30682.45455.900.02
A104-00-00_003123216.18336.00-6.155.38-4.175.380.0000060.43788.63674.440.03
A104-00-00_003123228 Bridge
HEC-RAS Plan: FEMAeff0607r (Continued)
ReachRiver StaQ TotalMin Ch ElW.S. ElevCrit W.S.E.G. ElevE.G. SlopeVel ChnlFlow AreaTop WidthFroude # Chl
(cfs)(ft)(ft)(ft)(ft)(ft/ft)(ft/s)(sq ft)(ft)
A104-00-00_003123241.9386.00-6.152.60-5.052.600.0000010.16535.35356.730.01
A104-00-00_003123241.93153.00-6.153.80-4.763.800.0000030.24644.80444.370.02
A104-00-00_003123241.93189.00-6.154.24-4.634.250.0000030.28684.94466.540.02
A104-00-00_003123241.93306.00-6.155.40-4.255.400.0000050.39790.96845.090.02
A104-00-00_003123413.8784.00-6.472.60-5.772.600.0000000.071214.95207.630.01
A104-00-00_003123413.87149.00-6.473.81-5.563.810.0000000.101473.19217.230.01
A104-00-00_003123413.87185.00-6.474.25-5.474.250.0000010.121569.55220.710.01
A104-00-00_003123413.87298.00-6.475.41-5.215.410.0000010.161829.93229.840.01
A104-00-00_003123478 Bridge
A104-00-00_003123543.9673.00-7.912.60-6.822.600.0000000.051352.92207.750.00
A104-00-00_003123543.96126.00-7.913.84-6.553.840.0000000.081618.13218.510.01
A104-00-00_003123543.96155.00-7.914.28-6.434.280.0000000.091714.98221.800.01
A104-00-00_003123543.96246.00-7.915.43-6.135.430.0000000.121975.89230.430.01
A104-00-00_003123573.9865.00-7.912.602.600.0000000.051353.00207.750.00
A104-00-00_003123573.98111.00-7.913.853.850.0000000.071620.13218.580.00
A104-00-00_003123573.98136.00-7.914.294.290.0000000.081717.00221.870.01
A104-00-00_003123573.98213.00-7.915.445.440.0000000.112029.27422.520.01
A104-00-00_003125230.5163.00-6.062.602.600.0000010.11567.04111.850.01
A104-00-00_003125230.51108.00-6.063.863.860.0000010.15711.42117.520.01
A104-00-00_003125230.51132.00-6.064.304.300.0000010.17763.55119.550.01
A104-00-00_003125230.51206.00-6.065.455.450.0000020.23917.30149.870.01
A104-00-00_003125953.4615.00-7.332.60-6.592.600.0000000.02750.42371.360.00
A104-00-00_003125953.4622.00-7.333.87-6.473.870.0000000.02914.88435.860.00
A104-00-00_003125953.4625.00-7.334.31-6.434.310.0000000.03972.98457.120.00
A104-00-00_003125953.4633.00-7.335.46-6.325.460.0000000.022371.75857.660.00
A104-00-00_003126874.7 8.00-6.702.602.600.0000000.01682.00132.200.00
A104-00-00_003126874.7 11.00-6.703.883.880.0000000.01854.45137.860.00
A104-00-00_003126874.7 12.00-6.704.324.320.0000000.01915.49139.800.00
A104-00-00_003126874.7 15.00-6.705.475.470.0000000.011110.08271.070.00
A104-00-00_003128390.274.00-7.582.602.600.0000000.01737.40128.210.00
A104-00-00_003128390.274.00-7.583.893.890.0000000.00905.66133.490.00
A104-00-00_003128390.275.00-7.584.334.330.0000000.01964.75135.290.00
A104-00-00_003128390.275.00-7.585.485.480.0000000.001234.56508.630.00
A104-00-00_003129636.511150.00-0.462.981.313.040.0006761.97624.81486.930.22
A104-00-00_003129636.511733.00-0.464.101.674.160.0004131.991026.91887.700.19
A104-00-00_003129636.512044.00-0.464.521.894.580.0003892.081194.081058.550.19
A104-00-00_003129636.512852.00-0.465.622.215.690.0003212.231745.651779.290.18
A104-00-00_003129964.241131.00-6.923.09-2.163.150.0002382.04611.96375.370.15
A104-00-00_003129964.241706.00-6.924.18-1.314.280.0002862.52918.47632.140.17
A104-00-00_003129964.242013.00-6.924.60-0.914.710.0003182.761090.68763.010.18
A104-00-00_003129964.242808.00-6.925.68-0.065.820.0003473.171820.951314.730.20
A104-00-00_003130279.821113.00-5.233.18-1.303.230.0002121.86790.15608.070.14
A104-00-00_003130279.821682.00-5.234.29-0.594.350.0002272.181445.44885.580.15
A104-00-00_003130279.821983.00-5.234.73-0.274.800.0002392.341768.941030.950.16
A104-00-00_003130279.822767.00-5.235.830.425.920.0002382.582701.511284.790.16
A104-00-00_003130576.681096.00-4.113.26-1.003.380.0006172.83401.64159.060.23
A104-00-00_003130576.681659.00-4.114.38-0.264.540.0008263.30646.66344.420.27
A104-00-00_003130576.681956.00-4.114.810.094.990.0008363.52772.75382.830.27
A104-00-00_003130576.682728.00-4.115.890.926.110.0008153.941169.50596.330.28
A104-00-00_003130658.051085.00-4.113.30-1.013.430.0004802.89375.3360.820.21
A104-00-00_003130658.051643.00-4.114.42-0.284.630.0007683.67447.9073.110.26
A104-00-00_003130658.051938.00-4.114.840.075.100.0008794.04479.3797.140.28
A104-00-00_003130658.052702.00-4.115.930.906.250.0011434.58846.26743.260.32
A104-00-00_003130707 Bridge
A104-00-00_003130756.121085.00-4.113.35-1.013.480.0004692.87378.32106.720.20
A104-00-00_003130756.121643.00-4.114.64-0.284.840.0007003.54464.09195.540.25
A104-00-00_003130756.121938.00-4.115.170.075.380.0008633.82529.73367.930.28
A104-00-00_003130756.122702.00-4.116.020.906.320.0010844.51843.27916.220.32
A104-00-00_003130777.061085.00-4.113.36-1.013.480.0004682.87378.63119.340.20
A104-00-00_003130777.061643.00-4.114.66-0.284.850.0007223.53465.56194.390.25
HEC-RAS Plan: FEMAeff0607r (Continued)
ReachRiver StaQ TotalMin Ch ElW.S. ElevCrit W.S.E.G. ElevE.G. SlopeVel ChnlFlow AreaTop WidthFroude # Chl
(cfs)(ft)(ft)(ft)(ft)(ft/ft)(ft/s)(sq ft)(ft)
A104-00-00_003130777.061938.00-4.115.190.075.410.0008573.80534.16373.470.28
A104-00-00_003130777.062702.00-4.116.050.896.350.0010724.49815.11611.380.31
A104-00-00_003131190.171063.00-3.943.613.690.0005042.28507.13200.290.21
A104-00-00_003131190.171612.00-3.944.985.070.0003942.47827.36269.340.19
A104-00-00_003131190.171901.00-3.945.545.640.0003782.60985.98296.050.19
A104-00-00_003131190.172650.00-3.946.496.620.0004263.061315.41439.980.21
A104-00-00_003131613.241040.20-3.433.78-0.863.810.0002001.45717.19190.090.13
A104-00-00_003131613.241580.80-3.435.14-0.295.180.0001781.571036.75266.410.13
A104-00-00_003131613.241863.50-3.435.70-0.055.740.0001681.651192.45292.850.13
A104-00-00_003131613.242597.20-3.436.680.536.740.0001811.921526.64435.550.14
A104-00-00_003032118.94611.60-2.403.863.880.0000850.98627.06163.970.09
A104-00-00_003032118.94906.60-2.405.225.240.0000701.07886.76220.570.08
A104-00-00_003032118.941051.00-2.405.785.800.0000671.121015.83244.870.08
A104-00-00_003032118.941389.40-2.406.786.800.0000691.261300.01337.160.09
A104-00-00_003032363.13596.00-2.353.883.910.0001441.21494.80142.490.11
A104-00-00_003032363.13883.00-2.355.245.270.0001101.30718.13187.140.10
A104-00-00_003032363.131025.00-2.355.795.820.0001041.36825.28202.360.10
A104-00-00_003032363.131369.00-2.356.796.820.0001061.531079.07348.880.10
A104-00-00_003032935.01559.60-1.913.980.414.000.0001901.30431.38129.440.13
A104-00-00_003032935.01829.90-1.915.311.055.340.0001391.36624.64163.020.11
A104-00-00_003032935.01967.10-1.915.861.215.890.0001281.41718.22177.930.11
A104-00-00_003032935.011323.20-1.916.851.596.890.0001301.60946.06325.980.11
A104-00-00_003033484.81544.00-1.964.160.814.210.0005411.92283.74103.440.20
A104-00-00_003033484.81806.00-1.965.441.305.500.0004121.82441.80141.940.18
A104-00-00_003033484.81940.00-1.965.981.526.030.0003611.80522.93224.350.17
A104-00-00_003033484.811289.00-1.966.962.067.010.0002871.90747.79394.090.16
A104-00-00_003034131.95525.00-1.464.441.124.510.0003842.01260.9367.960.18
A104-00-00_003034131.95779.00-1.465.701.645.770.0004162.19365.09105.580.19
A104-00-00_003034131.95908.00-1.466.221.876.300.0004462.23426.43129.590.20
A104-00-00_003034131.951250.00-1.467.182.437.270.0004632.40591.25290.370.20
A104-00-00_003034551.84514.00-2.134.664.730.0006622.12241.9587.380.22
A104-00-00_003034551.84761.00-2.135.905.970.0005112.06369.61119.060.20
A104-00-00_003034551.84889.00-2.136.426.480.0004292.07434.45131.980.19
A104-00-00_003034551.841225.00-2.137.377.450.0003912.25572.28157.580.19
A104-00-00_003035089.88499.00-0.795.005.080.0006192.30217.1665.950.22
A104-00-00_003035089.88740.00-0.796.176.270.0005452.47299.2773.870.22
A104-00-00_003035089.88864.00-0.796.666.760.0005342.57347.22124.770.22
A104-00-00_003035089.881194.00-0.797.607.720.0005562.86492.29176.680.23
A104-00-00_003035313.95493.00-0.795.072.565.500.0016215.3093.0866.440.40
A104-00-00_003035313.95731.00-0.796.163.466.830.0019426.55111.6773.830.45
A104-00-00_003035313.95854.00-0.796.613.887.400.0021307.16119.24121.990.48
A104-00-00_003035313.951181.00-0.797.434.918.650.0028208.87133.16213.680.56
A104-00-00_003035362.94Culvert
A104-00-00_003035429.04490.50-1.176.782.757.130.0008824.74103.4969.840.31
A104-00-00_003035429.04726.40-1.1710.153.7610.510.0005534.82150.70563.090.26
A104-00-00_003035429.04848.90-1.1711.394.2411.410.0000451.121726.41896.170.07
A104-00-00_003035429.041174.60-1.1711.795.4111.810.0000681.412089.04927.780.09
A104-00-00_003035539.81478.00-1.177.167.190.0001481.42337.7872.130.12
A104-00-00_003035539.81708.00-1.1710.5410.560.0000551.14897.68836.240.08
A104-00-00_003035539.81827.00-1.1711.3911.410.0000441.101639.21890.210.07
A104-00-00_003035539.811147.00-1.1711.7911.820.0000671.401998.63907.660.09
A104-00-00_003036182.56412.00-1.027.262.847.280.0001291.23334.5679.450.11
A104-00-00_003036182.56609.00-1.0210.583.4010.590.0000480.97629.87133.400.07
A104-00-00_003036182.56711.00-1.0211.423.6511.430.0000450.99743.35513.550.07
A104-00-00_003036182.56997.00-1.0211.844.2111.860.0000721.30828.55676.570.09
A104-00-00_003036868.14350.800.957.353.837.380.0001701.29272.4475.330.12
A104-00-00_003036868.14518.300.9510.624.2510.630.0000520.93558.56119.280.07
A104-00-00_003036868.14605.200.9511.454.4411.460.0000470.93700.67236.680.07
A104-00-00_003036868.14858.800.9511.884.9311.910.0000751.22803.61290.160.09
HEC-RASOutputforA104-12-01
HEC-RAS Plan: FEMAeff0607r River: A104-12-01 Reach: A104-12-01
ReachRiver StaQ TotalMin Ch ElW.S. ElevCrit W.S.E.G. ElevE.G. SlopeVel ChnlFlow AreaTop WidthFroude # Chl
(cfs)(ft)(ft)(ft)(ft)(ft/ft)(ft/s)(sq ft)(ft)
A104-12-01187.2905513.10-3.353.82-1.643.830.0000500.80675.16208.310.07
A104-12-01187.2905781.50-3.355.18-1.215.190.0000450.911055.17339.470.07
A104-12-01187.2905924.70-3.355.75-1.015.760.0000460.971256.06390.730.07
A104-12-01187.29051314.50-3.356.74-0.546.760.0000551.171713.17578.710.08
A104-12-01539.7813502.00-3.873.85-1.613.860.0000660.92560.70153.190.08
A104-12-01539.7813768.00-3.875.21-1.135.220.0000621.06804.99205.850.08
A104-12-01539.7813910.00-3.875.77-0.905.790.0000631.14928.72236.070.08
A104-12-01539.78131292.00-3.876.75-0.386.780.0000771.381240.17415.060.09
A104-12-011025.264487.00-3.103.87-1.183.890.0000721.12434.8183.780.08
A104-12-011025.264751.00-3.105.23-0.735.260.0000841.40537.33112.710.09
A104-12-011025.264891.00-3.105.80-0.515.830.0001171.40635.57169.820.11
A104-12-011025.2641263.00-3.106.790.006.830.0001371.68804.48356.630.12
A104-12-011072.448Bridge
A104-12-011095.755485.00-3.223.96-1.213.980.0000560.99489.14153.700.07
A104-12-011095.755748.00-3.225.46-0.775.470.0000621.07809.77206.570.08
A104-12-011095.755888.00-3.226.16-0.566.180.0000611.13966.12325.700.08
A104-12-011095.7551258.00-3.227.15-0.077.170.0000741.371310.98560.690.09
A104-12-011631.863469.00-3.364.00-1.114.020.0000640.94507.95123.410.08
A104-12-011631.863729.00-3.365.49-0.685.510.0000661.09720.12163.780.08
A104-12-011631.863867.00-3.366.19-0.476.210.0000631.14846.81202.460.08
A104-12-011631.8631226.00-3.367.190.017.220.0000771.391100.44450.240.09
A104-12-012117.061455.00-2.484.04-0.284.070.0001521.39327.3378.910.12
A104-12-012117.061713.00-2.485.520.275.560.0001511.62472.69138.900.12
A104-12-012117.061848.00-2.486.220.526.270.0001421.69569.79157.310.12
A104-12-012117.0611198.00-2.487.231.107.290.0001692.04728.41191.040.13
A104-12-012562.658442.70-1.145.013.775.560.0058546.0499.65104.180.62
A104-12-012562.658697.50-1.146.105.296.590.0038346.04283.23266.380.53
A104-12-012562.658831.80-1.146.665.637.060.0029105.74446.15394.340.47
A104-12-012562.6581172.90-1.147.566.447.830.0019715.32967.35791.840.40
A104-12-013057.251356.00-0.826.136.180.0005081.86203.21106.530.19
A104-12-013057.251541.00-0.827.047.110.0004492.10331.27163.880.19
A104-12-013057.251638.00-0.827.457.520.0004312.20402.48199.860.19
A104-12-013057.251888.00-0.828.168.250.0004652.54628.85484.970.20
A104-12-013121.046Culvert
A104-12-013186.055336.000.477.004.197.060.0005111.94237.74137.200.20
A104-12-013186.055506.000.478.955.328.980.0001651.54895.89676.510.12
A104-12-013186.055595.000.479.205.499.230.0001771.641065.58714.800.13
A104-12-013186.055826.000.479.495.919.540.0002562.051284.70775.650.15
A104-12-013552.112286.000.287.174.117.220.0003981.74188.21103.770.17
A104-12-013552.112419.000.289.024.869.040.0001401.41789.35825.570.11
A104-12-013552.112489.000.289.265.219.290.0001471.491003.46973.680.11
A104-12-013552.112672.000.289.595.769.630.0001991.801324.131073.170.13
A104-12-014053.186229.301.787.455.317.530.0008192.24103.8055.850.24
A104-12-014053.186323.701.789.105.759.150.0002851.83335.23460.030.16
A104-12-014053.186373.501.789.355.959.400.0002911.92470.42661.780.16
A104-12-014053.186507.301.789.706.419.760.0003352.17796.38909.350.17
REQUEST FOR DRAINAGE COMMITTEE AGENDA ITEM
Appropriation
Agenda Date Requested:January 16, 2012
:N/A
Source of Funds
Julian Garza
Requested By:
Account Number:N/A
Department: Planning
Amount Budgeted:N/A
Report: _X_Resolution: _ _Ordinance: ___
Amount Requested: N/A
Budgeted Item: XYES NO
Exhibit: Complete Final Letter Report
SUMMARY
On September 12, 2011, City Council authorized Klotz Associates to proceed with the first phase of the
Battleground Estates Preliminary Engineering Design report. This phase was performed to evaluate the
culvert restriction at North P Street and the F101-00-00 channel. The report concludes that removing the
dual 42 inch CMP restriction and extending the dual 8 foot by 10 foot box culverts would reduce the
water surface elevation at P Street and upstream approximately 1,000 feet, but does not extend to
Battleground Estates.
Staff will evaluate the channel cross section and potential obstructions, design the culvert extensions and
any future infrastructure needed to facilitate drainage of the Battleground Estates Subdivision. Staff will
also work with Harris County and Harris County Flood Control in an effort to partner on this project.
Based on the report findings and the City Wide Drainage Study staff does not recommend proceeding
with phase 2 of the Preliminary Engineering Report.
Action Required:
Present Battleground Estates Preliminary Engineering Design report findings.
Approved for Drainage Committee Agenda
___________________________________________________________
Steve Gillett, Interim City Manager Date
Hydrology
Model Basis
City Wide Drainage Study,
Existing-Conditions Model
Proposed-Solution Model
Cost Estimate
Results and Conclusions:
11752.8114.0019.5317.12-2.4119.4516.96-2.4919.2716.56-2.71
11592.8113.0019.4817.16-2.3219.4016.52-2.8819.2414.99-4.25
11542.8114.0019.4817.05-2.4319.4016.43-2.9719.2414.93-4.31
Ave. P
Ave. P
Sens Rd.
Railroad
SH 146
Railroad
Unnamed St.
Table 2
Preliminary Construction Cost Data
Total$85,000.00
4,3837
Photo 1Sediment on the outfall apron of 8'x10' culverts atF101-00-00 and Avenue P
Photo 2Sediment in the bottom of the 8'x10' RCBs serving F101-00-00 at Avenue P
Photo 3Upstream of structure at Avenue P (2 - 42" CMPs)
Photo 4Channel upstream of composite structure serving F101-00-00 at Avenue P
Photo 5Channel downstream of composite structure serving F101-00-00 at Avenue P
*-+96)7
REQUEST FOR DRAINAGE COMMITTEE AGENDA ITEM
Appropriation
Agenda Date Requested:January 16, 2012
:N/A
Source of Funds
Julian Garza
Requested By:
Account Number:N/A
Department: Planning
Amount Budgeted:N/A
Report: _X__Resolution: _ _Ordinance: ___
Amount Requested: N/A
Budgeted Item: YES NO
SUMMARY
th
The Texas Energy Coalition and its membership were present at the December 5Drainage Committee
Meeting to discuss the regulatory framework of the pipeline industry and address City of La Porte areas
of concern including conflicts of existing pipelines with new drainage facilities and new pipelines across
existing drainage facilities, construction practice of pipelines to insure drainage is not impeded during
construction and construction start times. The Texas Energy Coalition and its membership committed to
working with the City to address these concerns by meeting with staff members on a regular basis.
Staff recommends meeting with the Texas Energy Coalition and its membership on an as-neededbasis
during the regularly scheduled biweekly Staff Drainage Committee Meetings. A summary of these
meetings would be included in the report presented to City Council and the Drainage Committee meeting
as scheduled.
Action Required:
Discuss staff recommendation for meeting with the Texas Energy Coalition and its membership.
Approved for Drainage Committee Agenda
___________________________________________________________
Steve Gillett, Interim City Manager Date