Raw water systems and components including cooling and fire prevention systems, piping (Figure 2), screens (Figure 10), and valves related to each are susceptible to zebra mussel infestations. These systems are particularly susceptible if they leak or are used periodically (once every several days or weeks) and, therefore, do not become stagnant. Zebra mussels can foul the intake screens, piping, valves, and joints of these systems, preventing normal operation and leading to equipment damage. Control methods applicable to raw water systems include the use of non-contaminated (commercial or ground well) water, regular backflushing or backflushing using water heated above 38 °C, storing lines in the dry during periods of non-use, chemical treatment (e.g., chlorination), and minimizing leakage so that lines become anoxic.