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noupdate ofthisreport. Springfieldhasnotconductedasimilaranalysis. Therehasbeennoregional <br />assessmentoftheeffectivenessofI/Ireductionactivities, althoughtherehavebeensomeupdatesof <br />hydraulicmodels usedintheplanningofcapitalprojectsrelatedtowetweatherflowsandpeakcapacities <br />oftreatment units. <br />Specifically inregardsto privatelaterals, theCityofEugenePublicWorksMaintenance Division <br />prepareda “WastewaterServiceLateralsReport” in2010whichattemptedtodocumentthesizeofthe <br />privatelateralsysteminEugeneandestimatetheI/Iflowcontributionsfromprivatelateralstotheoverall <br />flowsinthesystem. TheanalysisuseddatafrombothEugene’smaintenancemanagementsystem and <br />theGISsystem, andgeneratedabestguessestimateofthesizeofthetotalservicelateralsystemat <br />approximately625miles, including about43,000serviceconnectionsandlowerlaterallineand59,000 <br />services on privateproperty orupperlaterals. ApplyingthesenumberstoobservedandestimatedI/Irates <br />frommain lineCCTVassessment dataforprivate laterals, thereportestimated anaverageaggregatedaily <br />2flowrateof885GPM, or1.27mgd, from privatelaterals (theseestimateswereconservative andmay <br />likelybelow, givenfieldobservations intheEugene/Springfieldsewersystem). Thereportcalculates an <br />annualcosttoconveyandtreatthisflowas $300,000. Thereportalsoconductedaliteraturereviewof <br />information relatedtoprivatelaterals, andsummarized that “…I/Icontributionrates fromtheservice <br />lateralsystemvarywidely, butgenerally fallbetween therange30–70%.” Springfieldhasnotconducted <br />asimilarassessmentofprivatelaterals, andatthistimehasnotcollated informationrelative tothe <br />numberof private laterals orscaleoftheprivate lateralsystem intheirwastewaterservicearea. <br />Theflowmonitoring programsforbothcitiesiscurrentlyinastateofchange. Springfieldisre- <br />evaluating itsmonitoringlocations anddevelopingastrategicplanforfuturemonitoring. Eugeneis <br />revamping itssanitarysewer collectionsystemmodel. Flowmonitoringequipmentforbothcommunities <br />needstobeupdated ingeneral.Neithercommunity hasa summarydocumentorreportontheflow <br />monitoringprogram proceduresorobjectives. Theflowmonitoringprogramsforthetwocommunities <br />arenotcloselycoordinated, formethodologyorobjectives. OtherthanintheWetWeatherFlow <br />ManagementPlan, there arenoclearly statedobjectivesorperformancemeasures forI/Ireduction <br />programs. Perspectivesontheobjectivesappeartohavechangedovertheyearsasthepersonnelinvolved <br />intheprogramhavechanged, andresources andprioritieshavechangedasbudgetavailabilityand <br />maintenanceneedshaveevolved. <br />Basedupontheexistingflowmonitoring dataandwastewatersystemmaintenancerecords, itisnot <br />possibletorenderadefinitive quantitative conclusionaboutthesignificance ofnon-sanitaryflowsfrom <br />privatelaterals totheoverall peakwetweather flowstransportedtotheregional wastewater treatment <br />facility. However, peeragencyinformation, visual observationsfromlocalCCTVinspections, and the <br />bestprofessionaljudgmentoflocalwastewater staffleadstoasubjectiveconclusion thatprivatelaterals <br />maybecontributing substantialI/Iflowsandthatthiswarrantsmore formal attentionandevaluation. <br />Summary ofPrivate LateralProgramsinOregon <br />Asurveywasconductedofpeerwastewater agenciesin Oregon toassesstheexistenceofprogramsto <br />controland reduceI/Ifromprivatelateralsandlearn fromanyexperience gainedinthedevelopment and <br />implementation ofsuchprograms. Thesurvey found thatseveralmunicipalities in Oregonhave <br />2The report notes “The reader iscautioned these are rough estimations dueto the incompleteness ofthe data <br />sources and thelevel of interpretation, but does provide useful insights based on observed findings.” <br />ATTACHMENT 1 <br />Page6of10 Appendix C-92020 Eugene Wastewater Master Plan