Gates, Stop Logs
Isolation gates are often suspended in the water above an opening. Fouling of the gate could interfere with proper insertion of the gate. Many gate panels have structural stiffening members such as channel sections or I-beam sections oriented horizontally. These sections have drain holes drilled in the web portion of the section. The drain holes can be plugged by mussels adding a significant amount of water that must be lifted when the gate is raised. If the gates are particularly heavily fouled, the motors used for lifting and lowering of the gates may not be up to the task.
Gates and stop logs all fit into vertical guide channels in the supporting side structures. The slots or channels are usually carbon steel C-channel shapes. Mussel fouling in the channel could make it difficult to properly seal the gate or stop logs.