leon creek wrc interconnect aerial crossing impact analysis€¦ · tfma fall 2012 wesley young,...
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TFMA Fall 2012
Wesley Young, P.E., CFM CPY
Jeff Wouters, P.E. CPY
Leon Creek WRCInterconnect
Aerial CrossingImpact Analysis
September 20, 2012
September 20, 2012
Leon Creek WRC Interconnect Impact AnalysisLeon Creek WRC Interconnect Impact Analysis
Agenda
• Project purpose and overview
• Hydraulic Results
• Impact Analysis
• Conclusions
September 20, 2012
Leon Creek WRC Interconnect Impact AnalysisLeon Creek WRC Interconnect Impact Analysis
Project Purpose
• Divert flows from SAWS’ Leon CreekWater Recycling Center (WRC) to SAWS’Dos Rios WRC via the Southwest BexarSewer Pipeline
• Eliminate a sewage lift station currentlyserving Texas A&M-San Antonio
September 20, 2012
Leon Creek WRC Interconnect Impact AnalysisLeon Creek WRC Interconnect Impact Analysis
Project OverviewLIFT
STATION
September 20, 2012
Leon Creek WRC Interconnect Impact AnalysisLeon Creek WRC Interconnect Impact Analysis
Project Benefits
• Eliminates the need for a costly expansionof the Leon Creek WRC
• Elimination of lift station reduces potentialfor odors near Texas A&M-San Antonio
• Accommodates future flows from theTexas A&M and Verano developments
September 20, 2012
Leon Creek WRC Interconnect Impact AnalysisLeon Creek WRC Interconnect Impact Analysis
Proposed Pipeline Alignment
Location Map
LEGEND
Leon Creek WRCInterconnect to the SBSP
Southwest Bexar SewerPipeline
Leon Creek WRC
Texas A&M
Verano
Lift Station
Cook Memorial Trusts
Toyota Manufacturing
City of SanAntonio
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Leon Creek WRC Interconnect Impact AnalysisLeon Creek WRC Interconnect Impact Analysis
Siphon Crossing Disadvantages
• Odor from septic conditions during periodsof no-flow and low-flow
• Hydrogen sulfide gas creating a morecorrosive environment inside the structure
• Solids settlement within the siphon
• Excavation or boring required
September 20, 2012
Leon Creek WRC Interconnect Impact AnalysisLeon Creek WRC Interconnect Impact Analysis
Diversion Solution with AerialCrossing
• Simplified configuration
• Reduced structural improvements
• Minimal mechanical requirements
• No additional bar screens
• Grit removal not required
• Reduced capital and O&M costs
September 20, 2012
Leon Creek WRC Interconnect Impact AnalysisLeon Creek WRC Interconnect Impact Analysis
Design Mitigation Actions
• 72-inch diameter steel carrier pipe that is ¾-inch thick
• 60-inch glass fiber reinforced plastic (FRP) wastewaterpipeline
• Annular space between steel carrier pipe and FRP pipefilled with high density polyurethane foam grout todistribute impact forces
• Concrete footings set 15-ft deep on 60-inch drilled shaftsubstructures into clay stone
• Each footing will be supported by a 24-inch concretecradle to hold the carrier pipe
September 20, 2012
Leon Creek WRC Interconnect Impact AnalysisLeon Creek WRC Interconnect Impact Analysis
September 20, 2012
Leon Creek WRC Interconnect Impact AnalysisLeon Creek WRC Interconnect Impact Analysis
Pipeline Crossing Hydraulics
0 100 200 300 400 500500
505
510
515
520
525
530
535
540
LeonComancheCreek20110929 Plan: AerialCrossWGradenew 12/1/2011RS = 3870 BR
Station (ft)
Ele
vation
(ft)
Legend
WS 100Future
Ground
BankSta
.1 .05 .065 .1
September 20, 2012
Leon Creek WRC Interconnect Impact AnalysisLeon Creek WRC Interconnect Impact Analysis
Hydraulic Study Results
• Pipeline modeled as a bridge deck
• 100-Year Flood WSELs Impinge on the Carrier Pipe
• Increases in WSELs mitigated by channel shaping at thecrossing
• Pipeline is approximately 1000-ft downstream ofMauermann Road
• Big Question – What if an SUV washed off Mauermann?
September 20, 2012
Leon Creek WRC Interconnect Impact AnalysisLeon Creek WRC Interconnect Impact Analysis
steelcasing pipe
FRPcarrier pipe
drilledshaft
concretecradle
concretepier cap
Aerial Crossing
concreteheadwall
September 20, 2012
Leon Creek WRC Interconnect Impact AnalysisLeon Creek WRC Interconnect Impact Analysis
72” steelcasing pipe
Typical Cross Section At Spacers
intermittentspacers
polyurethanegrout
60” FRPcarrier pipe