INTRODUCTION TO What is wastewater? WASTEWATER · PDF file1 INTRODUCTION TO WASTEWATER...
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Transcript of INTRODUCTION TO What is wastewater? WASTEWATER · PDF file1 INTRODUCTION TO WASTEWATER...
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INTRODUCTION TO INTRODUCTION TO WASTEWATER TREATMENT WASTEWATER TREATMENT
Justin Mechell, EITJustin Mechell, EIT
Extension Program SpecialistExtension Program Specialist
Texas AgriLife Extension ServiceTexas AgriLife Extension Service
OverviewOverviewWhat is wastewater?What is wastewater?
Why are we concerned about wastewater?Why are we concerned about wastewater?
The big picture.The big picture.
Goals for wastewater treatment are evolvingGoals for wastewater treatment are evolvinggg
How do we implement our infrastructure?How do we implement our infrastructure?
Wastewater Treatment Processes Wastewater Treatment Processes –– The end The end result is based upon your designresult is based upon your design
Existing systems need upgrades to meet new Existing systems need upgrades to meet new requirements: onsite and centralized optionsrequirements: onsite and centralized options
Wastewater infrastructureWastewater infrastructure All facilities serving All facilities serving
people generate people generate wastewaterwastewater
How to meet these How to meet these needs in an economicalneeds in an economicalneeds in an economical needs in an economical manner?manner?
Options:Options: OnOn--site site
ClusteredClustered
Centralized collection and Centralized collection and treatmenttreatment
Hydrologic Hydrologic cyclecycle
StreamWater Table
Onsite Wastewater Treatment System
WastewaterInput Runoff
Infiltration
Precipitation
Evapotranspiration
Impermeable Layer
Ground Water
Slow Moving
Wastewater constituentsWastewater constituents Organic matter Organic matter –– Biochemical Biochemical
Oxygen Demand Oxygen Demand –– indicatorindicator
Solids Solids –– TSSTSS
FOG FOG –– Fats, Oil & GreaseFats, Oil & Grease
Nutrients Nutrients –– Nitrogen, Nitrogen, Ph hPh hPhosphorousPhosphorous
PathogensPathogens
MedicationsMedications
ChemicalsChemicals
MetalsMetals
Public healthPublic health
Wastewater can contain disease causing PathogensWastewater can contain disease causing Pathogens BacteriaBacteria
VirusesViruses
ParasitesParasites
Ascaris lumbricoides
(roundworm)
ProtozoaProtozoa
Hepatitis A Virus
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Environmental Environmental protectionprotection
Treat contaminants before they reach surface water or Treat contaminants before they reach surface water or groundwatergroundwater NutrientsNutrients
•• PhosphorusPhosphorus
•• NitrogenNitrogen
Organic loadingOrganic loading•• BODBOD55
Bacteria Bacteria -- pathogenspathogens
The BIG pictureThe BIG picture
In order to be an effective, longIn order to be an effective, long--term sustainable term sustainable part of the wastewater infrastructure, onsite, part of the wastewater infrastructure, onsite, cluster or centralized wastewater treatment cluster or centralized wastewater treatment systems must be properly sited designedsystems must be properly sited designedsystems must be properly sited, designed, systems must be properly sited, designed, installed, operated and maintained. installed, operated and maintained.
We must have professionals who can provide We must have professionals who can provide system management servicessystem management services
Trained professionals for all scales of Trained professionals for all scales of infrastructure: onsite, cluster, & centralized.infrastructure: onsite, cluster, & centralized.
Permitting dispersal systemsPermitting dispersal systems Types: onsite, clustered, community/centralizedTypes: onsite, clustered, community/centralized OnOn--site wastewater treatment systemsite wastewater treatment system
Usually limited by maximum gallons per day (5,000 Usually limited by maximum gallons per day (5,000 gpdgpd))•• TCEQ guidance: 30 TAC, Chapter 285TCEQ guidance: 30 TAC, Chapter 285
Prescriptive rules Prescriptive rules –– local permitting, health departments local permitting, health departments Identified as :Identified as :Identified as : Identified as :
•• public public –– septic system; TCEQ septic system; TCEQ –– onon--site sewage facilities (OSSF); nationally site sewage facilities (OSSF); nationally -- OnOn--site site wastewater treatment system, (OWTS)wastewater treatment system, (OWTS)
Community systems (greater than 5000 Community systems (greater than 5000 gpdgpd)) Performance based Performance based –– State level permittingState level permitting
•• TCEQ guidance: 30 TAC chapter 217TCEQ guidance: 30 TAC chapter 217•• Potential groundwater impact due to water quality and moundingPotential groundwater impact due to water quality and mounding•• Detailed soil analysisDetailed soil analysis•• Location of water wells within ½ mileLocation of water wells within ½ mile•• Uniformity of effluent distributionUniformity of effluent distribution
Onsite wastewater treatment systemOnsite wastewater treatment system
Centralized treatment systemCentralized treatment system
Biosolids Land Application ProgramUniv of Nebraska Extension in Lancaster Countyhttp://lancaster.unl.edu/enviro/biosolids/sl05.jpg
Malfunctioning onsite systemMalfunctioning onsite system
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Malfunctioning centralized systemMalfunctioning centralized system MalfunctionMalfunction
Malfunctioning systemMalfunctioning system –– A wastewater A wastewater treatment system that is causing a nuisance or treatment system that is causing a nuisance or is not performing its intended function.is not performing its intended function.
NuisanceNuisance
sewage, human excreta, or other organic waste sewage, human excreta, or other organic waste discharged or exposed in a manner that makes it a discharged or exposed in a manner that makes it a potential instrument or medium in the transmission of potential instrument or medium in the transmission of disease to or between personsdisease to or between persons
an overflow from a septic tank or similar devicean overflow from a septic tank or similar device an overflow from a septic tank or similar device, an overflow from a septic tank or similar device, including surface discharge from or groundwater including surface discharge from or groundwater contamination by a component of an oncontamination by a component of an on--site sewage site sewage facility; or facility; or
a blatant discharge from a wastewater treatment a blatant discharge from a wastewater treatment system. system.
Evolution of wastewater Evolution of wastewater managementmanagementmanagementmanagement
Evolution of wastewater treatment Evolution of wastewater treatment goalsgoals
From outdoor plumbing to water reuseFrom outdoor plumbing to water reuse
Outdoor plumbing: the pit privyOutdoor plumbing: the pit privy
Goal: designated placeGoal: designated place
No carrier needed to No carrier needed to convey waste convey waste
Waste applied directly toWaste applied directly to Waste applied directly to Waste applied directly to the soil the soil
Public health concerns Public health concerns addressedaddressed
Management: relocateManagement: relocate
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Indoor plumbingIndoor plumbing Convenience Convenience
Water carrier to convey Water carrier to convey waste out of facilitywaste out of facility
‘Collection system’‘Collection system’
Public health andPublic health and Public health and Public health and pathogenspathogens
Management: keep pipe Management: keep pipe flowingflowing
Where does it go?Where does it go? OnsiteOnsite
SewerSewer
OnOn--site disposalsite disposal Goal: limit human contactGoal: limit human contact Keep wastewater below Keep wastewater below
ground ground Disposal optionsDisposal options Public health Public health
“Disposing” of pathogens“Disposing” of pathogens Disposing of pathogens Disposing of pathogens Treatment or dilution?Treatment or dilution?
Environment: groundwater Environment: groundwater contaminationcontamination
Management: install, flush Management: install, flush and forgetand forget
OffOff--site disposalsite disposal Centralized sewerCentralized sewer
Collection piping from Collection piping from houseshouses
Cluster Cluster
CommunityCommunity
T pe of se erT pe of se er Type of sewerType of sewer GravityGravity
Vacuum Vacuum
Small diameterSmall diameter
STEP /STEGSTEP /STEG
Treatment?Treatment?
Septic tank and soil treatment areaSeptic tank and soil treatment area Evolving goal: Evolving goal:
Disposal: effluent goes away versus treatmentDisposal: effluent goes away versus treatment
Dispersal: TREATMENTDispersal: TREATMENT
Public health AND environmental issues addressedPublic health AND environmental issues addressed
Management: Management: Disposal: often no management at all; Disposal: often no management at all;
Dispersal: system management is criticalDispersal: system management is critical
Groundwater
Well
Aerobic soil
Goal: TREATMENT AND DISPERSALGoal: TREATMENT AND DISPERSAL
Starting to address both environmental concerns in Starting to address both environmental concerns in addition to public health concernsaddition to public health concerns
Technological advancements now allow removal of:Technological advancements now allow removal of: Pathogens Pathogens SolidsSolids SolidsSolids NutrientsNutrients
System management is vital to treatmentSystem management is vital to treatment Goal is now DISPERSALGoal is now DISPERSAL
Hydrologic cycleHydrologic cycle
StreamWater Table
Onsite Wastewater Treatment System
WastewaterInput Runoff
OnOn--site system & hydrologic cyclesite system & hydrologic cycle
Impermeable Layer
Ground Water
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OffOff--site treatment and dispersalsite treatment and dispersal
Convey wastewater to Convey wastewater to central point.central point.
Contaminants removed?Contaminants removed? PrimaryPrimary
SecondarySecondary
TertiaryTertiary
Treatment for removal of Treatment for removal of specific contaminantsspecific contaminants
Discharge to surface Discharge to surface water resourceswater resources Durham County North Carolina WWTP
Centralized system & hydrologic cycleCentralized system & hydrologic cycle
Water reuseWater reuse
Goal: careful use of a Goal: careful use of a valuable resourcevaluable resource
Wastewater vs. waterWastewater vs. water
Potable vs. nonPotable vs. non--potablepotable Potable vs. nonPotable vs. non potable potable usesuses Landscape reuseLandscape reuse
Toilet flushingToilet flushing
Tough to meet potable Tough to meet potable qualityquality
Management: O&M is Management: O&M is even more criticaleven more critical
Evolution of wastewater goalsEvolution of wastewater goals Outdoor plumbingOutdoor plumbing Indoor plumbing Indoor plumbing -- remove wastewater from the home.remove wastewater from the home. Disposal onDisposal on--site site -- prevent wastewater from surfacing in prevent wastewater from surfacing in
the yard.the yard. Disposal offDisposal off--sitesite –– prevent contact at facility and convey toprevent contact at facility and convey to Disposal offDisposal off--site site –– prevent contact at facility and convey to prevent contact at facility and convey to
stream.stream. Treatment / dispersal onTreatment / dispersal on--site site -- provide effective treatment provide effective treatment
before effluent reaches surface or groundwater resources.before effluent reaches surface or groundwater resources. Treatment / dispersal offTreatment / dispersal off--site site –– provide effective treatment provide effective treatment
before discharging to stream.before discharging to stream. Reuse Reuse -- reclaim the water.reclaim the water.
Varying rates of evolutionVarying rates of evolution
Vary across the country Vary across the country
Driving forces for change Driving forces for change Limited water resourcesLimited water resources
E i t lE i t l Environmental concernsEnvironmental concerns•• TMDL programTMDL program
•• CZMP programCZMP program
•• Source water protectionSource water protection
Watershed protection plansWatershed protection plans
TMDL definedTMDL defined
TMDL = PSTMDL = PS--LA + NPSLA + NPS--LA + MOSLA + MOS
TMDLTMDL = Total maximum daily loadPSPS--LALA = Waste load allocation (PS)NPSNPS--LALA = Load allocation
(Anthropogenic NPS + Natural Sources)
MOSMOS = Margin of safety (plus Margin for Growth?)
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Changes in goals means:Changes in goals means: Approach must also changeApproach must also change
SitingSiting requirementsrequirements
Choice of treatment components and systemsChoice of treatment components and systems
System O&MSystem O&M
Management programManagement program
Industry needsIndustry needs
Public acceptance of changePublic acceptance of change
Public willing to pay for additional service, $$$Public willing to pay for additional service, $$$
Enforcement on participants not willing to Enforcement on participants not willing to change change –– public will to support enforcementpublic will to support enforcement
Decentralized wastewater treatment Decentralized wastewater treatment system:system:
Collection, treatment, and dispersal/reuse of Collection, treatment, and dispersal/reuse of wastewater from individual homes, clusters of wastewater from individual homes, clusters of homes, isolated communities, industries, or homes, isolated communities, industries, or institutional facilities at or near the point of wasteinstitutional facilities at or near the point of wasteinstitutional facilities, at or near the point of waste institutional facilities, at or near the point of waste generation.generation.
Onsite, cluster and centralized. Most cost effective Onsite, cluster and centralized. Most cost effective for the site conditions.for the site conditions.
Decentralized approachDecentralized approachDistributed management:Distributed management:
Method used to manage wastewater Method used to manage wastewater infrastructure where a responsible management infrastructure where a responsible management entity (RME) combines onsite, cluster and entity (RME) combines onsite, cluster and centralized treatment in a cost effective andcentralized treatment in a cost effective andcentralized treatment in a cost effective and centralized treatment in a cost effective and sustainable structure.sustainable structure.
What is an onsite wastewater treatment What is an onsite wastewater treatment system?system?
1.1. Wastewater sourceWastewater source
2.2. Collection and storageCollection and storage
3.3. Pretreatment componentsPretreatment components
4.4. Final treatment and dispersal componentsFinal treatment and dispersal components
Wastewater sourceWastewater source Facility typeFacility type DomesticDomestic
CommercialCommercial
IndustrialIndustrial
UserUser Owner/family Owner/family
EmployeesEmployees EmployeesEmployees
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CollectionCollection
Piping from facility Piping from facility with cleanoutwith cleanout BlackwaterBlackwater
GraywaterGraywater GraywaterGraywater
Collection OptionsCollection Options
Holding tanksHolding tanks Total flowTotal flow
BlackwaterBlackwater
Urine separationUrine separation
W t t ithW t t ith Waste stream with Waste stream with microbial inhibitorsmicrobial inhibitors
Composting toiletsComposting toilets
Incinerating toiletsIncinerating toilets
PretreatmentPretreatment
Septic tanksSeptic tanks
Aerobic treatment unitsAerobic treatment units
Media filtersMedia filters
Constructed wetlandsConstructed wetlands Constructed wetlandsConstructed wetlands
Membrane bioreactorsMembrane bioreactors
DisinfectionDisinfection
Final treatment and dispersal Final treatment and dispersal componentscomponents
Trench and bed Trench and bed distributiondistribution
Evapotranspiration bedsEvapotranspiration beds
Low pressureLow pressure Low pressure Low pressure distribution fielddistribution field
Drip fieldDrip field
Spray fieldSpray field
DischargeDischarge
What is a central sewer system?What is a central sewer system?
Same componentsSame components SourceSource
CollectionCollection
PretreatmentPretreatment PretreatmentPretreatment
Advanced treatmentAdvanced treatment
DisinfectionDisinfection
Dispersal Dispersal –– mostly mostly dischargedischarge
Responsible Responsible management entitymanagement entity
City of Cadillac, Michigan
How do we make the onHow do we make the on--site site wastewater treatment system work?wastewater treatment system work?
Evaluate the wastewater Evaluate the wastewater source: hydraulic and source: hydraulic and organic loadingorganic loading
Evaluate siteEvaluate site Wastewater treatmentWastewater treatment Wastewater treatmentWastewater treatment Wastewater acceptanceWastewater acceptance
Choose a final treatment Choose a final treatment and dispersal componentand dispersal component
Choose the appropriate Choose the appropriate pretreatment systempretreatment system
Operation and Operation and MaintenanceMaintenance
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Roles with septic system Roles with septic system managementmanagement
Site evaluationSite evaluation
DesignDesign
InstallationInstallation
StartupStartup
I tiI ti InspectionInspection
OperationOperation
MaintenanceMaintenance
MonitoringMonitoring
Pumping Pumping
Point of Sale InspectionPoint of Sale Inspection
Site evaluationSite evaluation
Comprehensive Comprehensive evaluation of soil evaluation of soil and site conditions and site conditions for a given land for a given land use.use.
DesignDesign
The process of selecting, sizing, locating, The process of selecting, sizing, locating, specifying and configuring treatment train specifying and configuring treatment train components that match site characteristics components that match site characteristics
d f ilit ll ti thd f ilit ll ti thand facility use as well as creating the and facility use as well as creating the associated written documentation. associated written documentation.
A design is also the written documentation A design is also the written documentation of size, location, specification and of size, location, specification and configuration.configuration.
InstallationInstallation
The assembly and The assembly and placement of placement of components of a components of a
t i l dit i l disystem, including system, including final grading and final grading and establishment of an establishment of an appropriate coverappropriate cover
StartupStartup
The process of setting The process of setting operational controls, operational controls, verifying component verifying component f ti df ti dfunction and function and documenting initial documenting initial operating conditions of operating conditions of a systema system
InspectionInspection
The evaluation of The evaluation of and reporting on and reporting on the status of athe status of athe status of a the status of a wastewater wastewater treatment systemtreatment system
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OperationOperation
The action of assessing The action of assessing whether whether eacheach component component of the system is of the system is functioning properlyfunctioning properly
Each component mustEach component must Each component must Each component must be operational if the be operational if the system as a whole is to system as a whole is to achieve the desired achieve the desired performanceperformance
MaintenanceMaintenance The action of conducting The action of conducting
required or routine required or routine planned performance planned performance checks, examinations, checks, examinations, upkeep, cleaning, or upkeep, cleaning, or
h i l dj t th i l dj t tmechanical adjustments mechanical adjustments to an onsite system.to an onsite system.
Includes Replacement of Includes Replacement of pumps, filters, aerator pumps, filters, aerator lines, valves or electrical lines, valves or electrical components.components.
MonitoringMonitoring
The action of The action of verifying verifying performance for a performance for a ppregulatory regulatory authority or a authority or a manufacturermanufacturer
PumpingPumping
The action of The action of removing septage removing septage from a wastewater from a wastewater treatment system treatment system componentcomponent
Point of sale inspectionPoint of sale inspection Inspect the treatment Inspect the treatment
system at the time of system at the time of property sale.property sale.
Chance to upgrade the Chance to upgrade the wastewater treatment wastewater treatment system if needed.system if needed.
Must have trained Must have trained professionals.professionals.
No licensing in Texas for No licensing in Texas for this person.this person.
RepairRepair
Is the action of Is the action of fixingfixing substandard or damaged substandard or damaged components.components. Required repairsRequired repairs
Recommended repairsRecommended repairs Recommended repairsRecommended repairs
UpgradesUpgrades
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Why perform operation and maintenance?Why perform operation and maintenance?
Keep systems Keep systems functioning properlyfunctioning properly
Maintain effluent qualityMaintain effluent quality Early detection of Early detection of
problems problems Public HealthPublic Health Environmental ProtectionEnvironmental Protection Public safety Public safety System ReliabilitySystem Reliability Customer SatisfactionCustomer Satisfaction
What quality do you desire?What quality do you desire? Primary treatmentPrimary treatment
Gross solids removalGross solids removal
Secondary treatmentSecondary treatment BOD & TSSBOD & TSSBOD & TSSBOD & TSS
DisinfectionDisinfection Pathogen removalPathogen removal
Tertiary treatmentTertiary treatment Nitrogen and Nitrogen and
phosphorous removalphosphorous removal
King County Washington, Vashon
Primary treatment componentsPrimary treatment components
Septic tankSeptic tank
Bar screenBar screen
Primary clarifierPrimary clarifier
Secondary treatment componentsSecondary treatment components SoilSoil
Aeration Aeration –– aerobic aerobic treatmenttreatment
Secondary Secondary clarifierclarifier
Sludge return to Sludge return to aerationaeration
Membrane Membrane bioreactorsbioreactors
Disinfection methodsDisinfection methods
SoilSoil
ChlorineChlorine
Ultraviolet LightUltraviolet Light
OzoneOzone
Tertiary treatment componentsTertiary treatment components
DilutionDilution
Soil & plantsSoil & plants
Nitrogen removalNitrogen removal DenitrificationDenitrification
Phosphorous removalPhosphorous removal Chemical additionChemical addition
PrecipitationPrecipitation
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SummarySummary
Wastewater management will play a vital role Wastewater management will play a vital role in our future infrastructure needs.in our future infrastructure needs.
Technologies are available for removing the Technologies are available for removing the tit t ftit t fconstituents of concern.constituents of concern.
Environmental regulations will continue to be Environmental regulations will continue to be more stringent.more stringent.
Environmental health is ultimate form of Environmental health is ultimate form of public health protection.public health protection.
SummarySummary
A site evaluation is critical to determining the A site evaluation is critical to determining the potential for a site to treat wastewater.potential for a site to treat wastewater.
Advanced pretreatment and final treatment Advanced pretreatment and final treatment and dispersal technologies are available forand dispersal technologies are available forand dispersal technologies are available for and dispersal technologies are available for most situations.most situations.
Select the most appropriate technology and Select the most appropriate technology and scale of system for your site.scale of system for your site.
Operation and maintenance is critical for Operation and maintenance is critical for longlong--term functionterm function