Salt and brackish waters are corrosive in nature. Anyone using equipment such as tripods in coastal and estuary setting would be well advised to take measures that protect the gear from being damaged. Salt water caught in the joints and other internal mechanisms could potentially eat away at it. So how do you resolve this issue? Break down your tripod after using it in a saline setting, rinse it off and then submerge it for several hours. This is a good idea to do on a regular basis anyway to remove debris from your gear. Afterwards remove your tripod from the water dry it off and wax it down using a floor wax (on need to wax the metal portions or the tripod just focus on the carbon fiber). This will fill in any areas damaged by corrosion and keep the corrosion from advancing.
Likewise you can use a product like INOX anti-corrosion, or an anti moisture lube. With the tripod broken down work the protective materials into the screw heads. Ensure all of the outer surfaces are covered thoroughly. Finally, for those of you who want to go the extra mile you can purchasing Drypod Waders. Drypod waders were created to protect tripods in salt and brackish water. The product is endorsed by many high-profile photographers and can be ordered online.