Designation:C1745/C1745M−11StandardTestMethodforMeasurementofHydraulicCharacteristicsofHydrodynamicStormwaterSeparatorsandUndergroundSettlingDevices1ThisstandardisissuedunderthefixeddesignationC1745/C1745M;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodconcernsmeasurementofselectedhydrauliccharacteristicsofhydrodynamicseparatorsandun-dergroundsettlingdevicescriticaltotheirfunctionasstorm-watertreatmentdevices.1.2Unitstestedshallbeofasizecommonlymanufactured,notascalemodel.1.3Aseachstormwatertreatmentdeviceisuniqueindesign,soareitshydrauliccharacteristics(flowversusheadandlosscoefficients).Asufficientnumberofaccuratelymea-sureddatapointsareneededtodefineproperlythehydrauliccharacteristicsofeachtestunit.Therefore,itisimperativethattheunitsetupandsubsequenttestingmethodologiesbewelldefinedandexecutedtoensureaccurateflowandelevationdata.1.4Thistestmethodaddressesgravityflowoperationonly.Itdoesnotaddressperformanceofunitsoperatingunderpressurizedconditions.1.5ThevaluesstatedineitherSIunitsorinch-poundunitsaretoberegardedseparatelyasstandard.Thevaluesstatedineachsystemmaynotbeexactequivalents;therefore,eachsystemshallbeusedindependentlyoftheother.Combiningvaluesfromthetwosystemsmayresultinnon-conformancewiththestandard.1.6Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:2D3858TestMethodforOpen-ChannelFlowMeasurementofWaterbyVelocity-AreaMethodD4409TestMethodforVelocityMeasurementsofWaterinOpenChannelswithRotatingElementCurrentMetersD5089TestMethodforVelocityMeasurementsofWaterinOpenChannelswithElectromagneticCurren...
