Table 4 Control Strategies Appropriate for Public Facilities

Component	Control Strategies
Measurement Systems	Preventive Antifouling Coatings - Use Coating System A or B. Chemical Treatment - There is a wide variety of chemical treatments utilizing oxidizing and nonoxidizing chemicals, which vary in concentrations, durations, and lethality. Toxic Construction Materials - Retrofit navigation aids with materials toxic to zebra mussels such as copper, copper alloys, or galvanized piping.
	Reactive Mechanical Cleaning - Any method, such as scraping, high pressure water jet cleaning with pressure between 27,600 and 68,900 kPa, or carbon dioxide pellet blasting. Caution with regard to damaging sensitive instruments may require hands-on cleaning. Chemical Treatment - There is a wide variety of chemical treatments using oxidizing and nonoxidizing chemicals, which vary in concentrations, durations, and lethality.
Raw Water Systems	Preventive Mechanical Filtration - A number of filter and strainer components are available for zebra mussel control. Chemical Treatment - There is a wide variety of chemical treatments utilizing oxidizing and nonoxidizing chemicals which vary in concentrations, durations, and lethality. Noncontaminated Water Source - Use water from a source known to be free of zebra mussels adults and veligers (i.e., stored water, city water, well water). Copper Piping - Retrofit piping systems with copper, copper alloys, or galvanized piping. Self-Cleaning Nozzles - Piping systems ending in restrictive nozzles or valves should be retrofitted with self cleaning nozzles and copper or coating valves.
	Reactive Chemical Treatment - There is a wide variety of chemical treatments utilizing oxidizing and nonoxidizing chemicals, which vary in concentrations, durations, and lethality. Periodic Operation - Water velocities in most piping systems are high enough that periodic operation will flush out mussels and shell debris. Component Replacement - Replace fouled component. Replacement of component should take zebra mussels into consideration.
Chamber Gates	Preventive Antifouling Coatings - Use Coating System A or B. Frequent Use - Gate movement and water velocities help prevent excessive settlement and infestation at locations that zebra mussel infestations might inhibit gate movement.
	Reactive Mechanical Cleaning- Any method, such as scraping, high pressure water jet cleaning with pressure between 27,600 and 68,900 kPa, or carbon dioxide pellet blasting. Freezing/Desiccation - Aerial exposure during the winter months when temperatures are below freezing (0 ?C) or during hot, dry summer months. Component Replacement - Replace fouled component. Replacement of component should take zebra mussel toleration into consideration.
Spillway Gates	Preventive Antifouling Coatings - Use Coating System A or B. Frequent Use - Gate movement and water velocities help prevent excessive settlement and infestation at locations that zebra mussel infestations might inhibit gate movement.
	Reactive Mechanical Cleaning - Any method, such as scraping, high pressure water jet cleaning with pressure between 27,600 and 68,900 kPa, or carbon dioxide pellet blasting. Freezing/Desiccation - Aerial exposure during the winter months when temperatures are below freezing (0 °C) or during hot, dry summer months.
Culvert Valves and Racks	Preventive Antifouling Coatings - Use Coating System A or B. Frequent Use - Gate movement and water velocities help prevent excessive settlement and infestation at locations that zebra mussel infestations might inhibit gate movement.
	Reactive Mechanical cleaning - Any method, such as scraping, high pressure water jet cleaning with pressure between 27,600 and 68,900 kPa, or carbon dioxide pellet blasting.
Emergency Closure and Dewatering Gates	Preventive Antifouling Coatings - Use Coating System A or B.
	Reactive Mechanical cleaning - Any method, such as scraping, high pressure water jet cleaning with pressure between 27,600 and 68,900 kPa, or carbon dioxide pellet blasting. Occasional Use - Gate movement and water velocities help prevent excessive settlement and infestation at locations that zebra mussel infestations might inhibit gate movement. Freezing/Desiccation - Aerial exposure during the winter months when temperatures are below freezing (0 °C) or during hot, dry summer months.
Concrete Surfaces	Preventive Antifouling Coatings - Apply toxic or nontoxic antifouling to concrete surfaced.
	Reactive Mechanical Cleaning - Any method, such as scraping, high pressure water jet cleaning with pressure between 27,600 and 68,900 kPa, or carbon dioxide pellet blasting. Freezing/Desiccation - Aerial exposure during the winter months when temperatures are below freezing (0 °C) or during hot, dry summer months.
Navigation Aids	Preventive Repellent Construction Materials - Retrofit navigation aids with materials toxic to zebra mussels such as copper, copper alloys, or galvanized piping. Antifouling Coatings - Apply toxic or nontoxic antifouling to navigation aid of concern.
	Reactive Mechanical Cleaning - Any method, such as scraping, high pressure water jet cleaning with pressure between 27,600 and 68,900 kPa, or carbon dioxide pellet blasting. Freezing/Desiccation - Aerial exposure during the winter months when temperatures are below freezing (0 °C) or during hot, dry summer months.