the zebra mussel what a homeowner needs to know 1
TRANSCRIPT
The ZebraThe ZebraMusselMussel
What A What A
Homeowner Homeowner
Needs to KnowNeeds to Know
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June 1988 - Lake St. ClairJune 1988 - Lake St. Clair
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Zebra Mussel U.S. RangeZebra Mussel U.S. Range
December 1989December 1989 3
December 1990December 1990
Zebra Mussel U.S. RangeZebra Mussel U.S. Range
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December 1992December 1992
Zebra Mussel U.S. RangeZebra Mussel U.S. Range
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Zebra Mussel U.S. RangeZebra Mussel U.S. Range
December 1999December 1999 6
Potential Zebra Mussel U.S. RangePotential Zebra Mussel U.S. Range
December 2020?December 2020? 7
Recreational Boating...Recreational Boating...
The most likely inland spread vectorThe most likely inland spread vector 8
Water Treatment PlantWater Treatment PlantOzone Contact ChamberOzone Contact Chamber
(Monroe, MI, WTP)(Monroe, MI, WTP)
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Circulating WaterCirculating WaterPump Bell HousingPump Bell Housing(Detroit Edison, Monroe, MI)(Detroit Edison, Monroe, MI)
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But…But…Huge pipes aren’t the only ones at risk.Huge pipes aren’t the only ones at risk.Zebra mussels are already clogging Zebra mussels are already clogging thousands of small intakes, as well.thousands of small intakes, as well.
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• Densities of mussel veligers in water column are lowDensities of mussel veligers in water column are low
• Power plants and drinking water facilities have huge Power plants and drinking water facilities have huge water demands and draw in millions of veligerswater demands and draw in millions of veligers
• Power plants and water treatment plants pump water Power plants and water treatment plants pump water for long periods of time, sucking in more veligersfor long periods of time, sucking in more veligers
• Many residential systems may face imminent failure Many residential systems may face imminent failure but haven’t been clogged yetbut haven’t been clogged yet
• Many people affected by power plant or water treat-Many people affected by power plant or water treat-ment plant shutdowns; clogged residential pipes ment plant shutdowns; clogged residential pipes impact fewerimpact fewer
Why Haven’t We Heard of Why Haven’t We Heard of This Problem Before Now?This Problem Before Now?
• Early colonization is spotty with low mussel densitiesEarly colonization is spotty with low mussel densities
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Watch carefully…Watch carefully…Zebra MusselsZebra Musselscome in ALL sizescome in ALL sizesand colorationand colorationpatternspatterns
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Water Intakes =Water Intakes =Excellent Zebra Mussel HabitatExcellent Zebra Mussel Habitat
• Continuous removal of wastes Continuous removal of wastes
• Protection from predationProtection from predation
• Protection from severe weatherProtection from severe weather
• Continuous source of food and oxygenContinuous source of food and oxygen
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Byssal Threads…..Byssal Threads…..
The zebra mussel's secret weaponThe zebra mussel's secret weapon15
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Zebra mussels can completely Zebra mussels can completely plug small water intake pipesplug small water intake pipes
in very little timein very little time
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Zebra Musselsin
Residential Water Systems
Zebra Musselsin
Residential Water Systems
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Zebra Mussel Fouling ofZebra Mussel Fouling ofResidential Water SystemsResidential Water Systems
• StrainerStrainer
• Foot valveFoot valve
• PumpPump
• Pipe itselfPipe itself
• Storage/pressure tankStorage/pressure tank
• Distribution pipesDistribution pipes
• Intake pipeIntake pipe
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Zebra Mussel Impacts onZebra Mussel Impacts onResidential Water SystemsResidential Water Systems
• Obstruction of foot valveObstruction of foot valve
• Clogging of intake pipeClogging of intake pipe
• Wear & tear on pumpWear & tear on pump
• Clogging of distribution pipesClogging of distribution pipes
• Taste & odor problemsTaste & odor problems
• Increased corrosionIncreased corrosion
• Loss of pumping efficiencyLoss of pumping efficiency
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• Is there a noticeable Is there a noticeable decrease in water decrease in water volume and pressure?volume and pressure?
• Are there unpleasant Are there unpleasant tastes and odors in the tastes and odors in the water?water?
• Are mussels growing Are mussels growing around or within around or within mouth of pipe?mouth of pipe?
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Factors Influencing Rate of Factors Influencing Rate of Zebra Mussel Fouling of Zebra Mussel Fouling of
Residential Water SystemsResidential Water Systems
• Extent of zebra mussel colonization near Extent of zebra mussel colonization near mouth of intakemouth of intake
• Position of the mouth of intake in the waterPosition of the mouth of intake in the water
• Composition of the intake pipeComposition of the intake pipe
• Volume and velocity of water flowing through Volume and velocity of water flowing through the pipethe pipe
• Water chemistry of the waterbodyWater chemistry of the waterbody
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Reducing the Risk ofZebra Mussel FoulingReducing the Risk ofZebra Mussel Fouling
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• Periodically (some mussel growth is Periodically (some mussel growth is allowed, followed by removal of the allowed, followed by removal of the mussels)mussels)
When to Implement When to Implement Zebra Mussel Control in Zebra Mussel Control in
Residential Water SystemsResidential Water Systems
• Continually (Continually (nono mussels tolerated mussels tolerated everever))
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Residential Water SystemsResidential Water Systems
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Residential Water SystemsResidential Water Systems
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• Most difficult to protectMost difficult to protect
• Often least costly to repairOften least costly to repair
Residential Water SystemsResidential Water Systems
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• Easiest to protectEasiest to protect
• Most costly to repairMost costly to repair
Residential Water SystemsResidential Water Systems
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Protecting theOnshore Component
ofResidential Water Systems
Protecting theOnshore Component
ofResidential Water Systems
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Onshore ComponentOnshore ComponentControl AlternativesControl Alternatives
• Chlorine injection at pump or pressure Chlorine injection at pump or pressure tanktank
• Combination of filtration & chlorinationCombination of filtration & chlorination
• Replaceable or cleanable in-line filterReplaceable or cleanable in-line filter
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In-Line FiltrationIn-Line Filtration
• 40 micron maximum
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• Removes all life stages
Whole HouseWhole HouseIn-Line FiltersIn-Line Filters
• Ceramic filters (50 Ceramic filters (50 ))
• Spun cellulose or ceramic fiber cartridges (<10 Spun cellulose or ceramic fiber cartridges (<10 ))
• Dual media filtersDual media filters
• Fiber media around activated charcoal core (<10 Fiber media around activated charcoal core (<10 ))
• Removes many flavors & odorsRemoves many flavors & odors
• Back-flushable filters or microstrainers (<10 Back-flushable filters or microstrainers (<10 ))
• Single media filamentous “angel hair” (25 - 50 Single media filamentous “angel hair” (25 - 50 ))
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Whole HouseWhole HouseIn-Line FiltersIn-Line Filters
• Require periodic filter cartridge Require periodic filter cartridge replacementreplacement
• Increased backpressure can force Increased backpressure can force live larvae through filterlive larvae through filter
• Back-flushable filters clean filter media Back-flushable filters clean filter media by reversing flow of water and flushing by reversing flow of water and flushing out filter mediaout filter media
• Least expensiveLeast expensive
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Whole HouseWhole HouseIn-Line FiltersIn-Line Filters
• Amount of silt, algae, zebra mussel veligers, and Amount of silt, algae, zebra mussel veligers, and other particles drawn into systemother particles drawn into system
• Intake’s location in the waterbody Intake’s location in the waterbody
• Time of yearTime of year
Cleaning / replacement timing depends upon:Cleaning / replacement timing depends upon:
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• Spring & summer silt loadsSpring & summer silt loads
• Storm silt loadsStorm silt loads
• Summer algal growthSummer algal growth
Whole HouseWhole HouseIn-Line FiltersIn-Line Filters
• Cleaning / replacement of clogged filters is an Cleaning / replacement of clogged filters is an on-going cost & time commitmenton-going cost & time commitment
• Automatic back-flushable filters can eliminate Automatic back-flushable filters can eliminate one of the maintenance tasksone of the maintenance tasks
• Do not allow material trapped within filter to Do not allow material trapped within filter to bypass the filter during cleaning / replacementbypass the filter during cleaning / replacement
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In-Line ChlorinationIn-Line Chlorination
• Kills all life stages
• Kills many other pathogens
• Remove taste with carbon filter 36
Filter-Chlorinator ComboFilter-Chlorinator Combo
• “Healthier” water
• Kills or removes all mussels37
Hand-Driven Shore WellHand-Driven Shore Well
Pumphouse
Driven pipewith well point
Infiltrationfrom waterbody
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"High Tech" Shore Well"High Tech" Shore Well
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Shore Well with Infiltration ChannelShore Well with Infiltration Channel
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• May not be viable alternative May not be viable alternative where:where:
• No available aquiferNo available aquifer
• Sulfurous waterSulfurous water
• Salty waterSalty water
• Polluted ground waterPolluted ground water
Drilled WellsDrilled Wells
The ultimate onshore The ultimate onshore preventive measurepreventive measure
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Offshore StrainersOffshore Strainers
Effectiveness depends upon:Effectiveness depends upon:
• Mesh size of screenMesh size of screen
• Size of mussels being drawn into pipeSize of mussels being drawn into pipe
• Common mesh on small intake (1/4 - 1/2 Common mesh on small intake (1/4 - 1/2 inch) keeps out leaves but not zebra mussel inch) keeps out leaves but not zebra mussel veligers (as small as 70 veligers (as small as 70 {3/1000 inch}) {3/1000 inch})
• Simple screens are ineffective as a zebra Simple screens are ineffective as a zebra mussel control methodmussel control method
Use of screens or strainers at intake end of pipeUse of screens or strainers at intake end of pipe
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Offshore StrainersOffshore Strainers
• Too small openings can clog quickly with silt, Too small openings can clog quickly with silt, algae, and debrisalgae, and debris
• Screens can become fouledScreens can become fouled
Effectiveness can be increased by reducing Effectiveness can be increased by reducing mesh sizemesh size
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Offshore FiltrationOffshore Filtration
Manufactured alternativesManufactured alternatives
• Prefabricated sand filtersPrefabricated sand filters
• Ceramic filtersCeramic filters
• Cartridge filtersCartridge filters
Constructed alternativesConstructed alternatives
• Infiltration galleries Infiltration galleries
• Raised fill bedsRaised fill beds
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Infiltration GalleryInfiltration Gallery
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Raised Fill BedRaised Fill Bed
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Backflushing Offshore FiltersBackflushing Offshore Filters
• Backflush by pumping water from shore through Backflush by pumping water from shore through pipe system to flush out fine particles pipe system to flush out fine particles
• Sand beds can become compacted over timeSand beds can become compacted over time
• Infiltration galleries and raised fill beds will Infiltration galleries and raised fill beds will eventually clog with fine particleseventually clog with fine particles
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• Cracks can form in sandCracks can form in sand
• Zebra mussel veligers can be drawn into pipeZebra mussel veligers can be drawn into pipe
• Backflushing “fluffs” sand up, prevents cracksBackflushing “fluffs” sand up, prevents cracks
Prefabricated Sand FilterPrefabricated Sand Filter
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Manufactured Offshore FiltersManufactured Offshore Filters
• When, where, how long, under what conditions When, where, how long, under what conditions have filters been field tested?have filters been field tested?
• Names of clients with filters in water for Names of clients with filters in water for reasonable length of timereasonable length of time
• What happens if system clogs prematurely?What happens if system clogs prematurely?
• Is automatic backwashing available as option?Is automatic backwashing available as option?
Homeowners should investigate the productHomeowners should investigate the product
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Offshore Filters andOffshore Filters andWater PotabilityWater Potability
• By itself, offshore filtration is not intended to By itself, offshore filtration is not intended to provide potable (drinkable) waterprovide potable (drinkable) water
• Additional treatment by chlorination or Additional treatment by chlorination or ultraviolet light needed to kill bacteriaultraviolet light needed to kill bacteria
Consult county Cooperative Extension Service or Consult county Cooperative Extension Service or health department about drinking water standardshealth department about drinking water standards
Offshore sand filtration can remove zebra mussels Offshore sand filtration can remove zebra mussels and other large particlesand other large particles
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Environmental Impacts ofEnvironmental Impacts ofConstructed Offshore FiltersConstructed Offshore Filters
• Permanent change in bottom habitat type from Permanent change in bottom habitat type from natural to human-influenced substratenatural to human-influenced substrate
• Turbidity during excavation and backfilling impacts Turbidity during excavation and backfilling impacts local water quality temporarilylocal water quality temporarily
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• Use trenching equipment rather than backhoesUse trenching equipment rather than backhoes
• Use silt screens around excavation siteUse silt screens around excavation site
• Disturbance of natural lake or river bottom habitatDisturbance of natural lake or river bottom habitat• New habitat provided by stone cover materialNew habitat provided by stone cover material
• Prefabricated sand filter minimizes habitat loss Prefabricated sand filter minimizes habitat loss with smaller disturbance “footprint” with smaller disturbance “footprint”
Offshore Ceramic andOffshore Ceramic andCartridge FiltersCartridge Filters
• Porosity should be small enough so that no mussel Porosity should be small enough so that no mussel life stages will pass live into intake pipelife stages will pass live into intake pipe
• Available with manual or automatic backwashAvailable with manual or automatic backwash
• Should ask how often the filter media needs to be Should ask how often the filter media needs to be replaced or cleanedreplaced or cleaned
• Abrasive ceramic filter media removes or Abrasive ceramic filter media removes or destroys mussel veligersdestroys mussel veligers
• Cartridge filters trap particles, including zebra Cartridge filters trap particles, including zebra mussel veligersmussel veligers
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Nonfouling Pipe MaterialsNonfouling Pipe Materials
• Discourage zebra mussel attachmentDiscourage zebra mussel attachment
• Lose effectiveness as they corrode or oxidizeLose effectiveness as they corrode or oxidize
• Should be augmented by other methodsShould be augmented by other methods
Copper or galvanized intake pipesCopper or galvanized intake pipes
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Periodic Cleaning ofPeriodic Cleaning ofOffshore ComponentOffshore Component
• Protect onshore component with its own systemProtect onshore component with its own system
• Install “Y” connection cleanout at shore end of Install “Y” connection cleanout at shore end of pipe to facilitate cleaningpipe to facilitate cleaning
• Allows some clogging by mussels, followed by Allows some clogging by mussels, followed by periodic maintenanceperiodic maintenance
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• CleaningCleaning
• MechanicalMechanical
• ThermalThermal
• Pipe replacementPipe replacement
• Loosened mussels must be removed by:Loosened mussels must be removed by:
• Pumping through a strainer at the pumpPumping through a strainer at the pump
• Opening foot valve and backflushingOpening foot valve and backflushing
• Not possible in pipes with:Not possible in pipes with:
Periodic Cleaning ofPeriodic Cleaning ofOffshore ComponentOffshore Component
Plumber’s snake for short pipes with easy accessPlumber’s snake for short pipes with easy access
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• Tight bendsTight bends
• Check valvesCheck valves
• Radical diameter changesRadical diameter changes
Oxygen DeprivationOxygen Deprivation
• Seal both ends of pipe long enough for water to lose all Seal both ends of pipe long enough for water to lose all of its oxygenof its oxygen
• Oxygen demand greatest in warm waterOxygen demand greatest in warm water
• Oxygen deprivation most effective in summerOxygen deprivation most effective in summer
• 2 to 3 days anaerobic water at 74º F = 100% kill2 to 3 days anaerobic water at 74º F = 100% kill
• Most suited to weekend cottages that routinely have Most suited to weekend cottages that routinely have water system shutdownswater system shutdowns
• Year-round homes will need second intakeYear-round homes will need second intake
• Zebra mussels “breathe” oxygen as water passes Zebra mussels “breathe” oxygen as water passes over their gills over their gills
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Removable Intake PipesRemovable Intake Pipes
• Single short flexible plastic pipe directly on lakebedSingle short flexible plastic pipe directly on lakebed
• Pull from water - leave on shore - dry in sunPull from water - leave on shore - dry in sun
• Dead mussels “snaked” from pipeDead mussels “snaked” from pipe• Replace into water next weekendReplace into water next weekend• Several times a season based on speed of foulingSeveral times a season based on speed of fouling
• Dual short flexible plastic pipesDual short flexible plastic pipes
• Pull one-at-a-time from water, leave on shore, dry Pull one-at-a-time from water, leave on shore, dry in sun, and cleanin sun, and clean
• Pumping continues through second pipe Pumping continues through second pipe
• Onshore piping protected by onshore filtrationOnshore piping protected by onshore filtration
Weekend cottage: low water demand & not for drinkingWeekend cottage: low water demand & not for drinking
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Thermal TreatmentThermal Treatment
• Hot water discharge = negative environmental impactHot water discharge = negative environmental impact• Dead mussels must be removed by backflushingDead mussels must be removed by backflushing• Portable steam generator from shore end of pipePortable steam generator from shore end of pipe
• Live steam = instant killLive steam = instant kill• Less hot water dischargeLess hot water discharge
Periodic flushing with hot waterPeriodic flushing with hot water
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• 90º F for about 1 hour = 100% kill90º F for about 1 hour = 100% kill• > 130º F = immediate kill> 130º F = immediate kill• Foot valve must be open to allow flow of hot waterFoot valve must be open to allow flow of hot water• Cold lake water is heat sink - need enough hot water to Cold lake water is heat sink - need enough hot water to fill pipe and keep hot long enough for killfill pipe and keep hot long enough for kill
Chemical TreatmentChemical Treatment
• Never pour or backwash chemicals down intakesNever pour or backwash chemicals down intakes
• Environmentally harmful effects on fish, Environmentally harmful effects on fish, zooplankton, and bottom-dwelling invertebrateszooplankton, and bottom-dwelling invertebrates
• Might be harmful to human healthMight be harmful to human health
• Could be illegal if discharged into surface watersCould be illegal if discharged into surface waters
• Not effective in killing zebra mussels due to short Not effective in killing zebra mussels due to short contact time afforded in a residential intake pipecontact time afforded in a residential intake pipe
• No environmentally sound chemical treatment No environmentally sound chemical treatment system for offshore part of residential water intakessystem for offshore part of residential water intakes
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Deeper IntakesDeeper Intakes
• Water too coldWater too cold
• Insufficient food supplyInsufficient food supply
• Zebra mussels survive near-freezing Great Lakes Zebra mussels survive near-freezing Great Lakes
winters with little damage below ice scour zonewinters with little damage below ice scour zone
• Veligers found down to about 200+ feetVeligers found down to about 200+ feet
• Cost of very deep intakes prohibitively expensiveCost of very deep intakes prohibitively expensive
• IfIf waters below thermocline become oxygen depleted, waters below thermocline become oxygen depleted,
sub-thermocline intakes sub-thermocline intakes couldcould minimize colonization minimize colonization
• Deep water intake might minimize colonizationDeep water intake might minimize colonization
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Multi-Residence SystemsMulti-Residence Systems
• Cost per residence could be lower than for single Cost per residence could be lower than for single
residence systemsresidence systems
• Multi-residence systems help eliminate proliferation Multi-residence systems help eliminate proliferation
of smaller, less efficient individual systemsof smaller, less efficient individual systems
• Might be more environmentally soundMight be more environmentally sound
Most control alternatives can be scaled up to meet Most control alternatives can be scaled up to meet needs of multiple residencesneeds of multiple residences
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Written and Produced By
Charles R. O’Neill, Jr.
New York Sea Grant
2001