How to get rid of mildew smell from my shower drain?

 
Examine the Problem
 

• Begin by checking if the odor is coming solely from the drain and note any signs of discoloration or buildup that may indicate mold or mildew.
• Determine if the smell persists after using the shower, which suggests that stagnant water or biofilm might be accumulating in the pipes.

 
Gather Cleaning Supplies
 

• White vinegar
• Baking soda
• Boiling water
• A soft-bristled brush or old toothbrush
• Protective gloves
• A cloth or sponge

 
Clean the Drain Thoroughly
 

• Remove the drain cover if possible to expose more of the drain’s interior.
• Pour a generous amount of boiling water directly into the drain to help loosen any soap scum, hair, or organic matter.
• Sprinkle a layer of baking soda over the drain opening, ensuring it gets into the crevices and around the trapped debris.
• Slowly pour white vinegar into the drain. The mixture will fizz and help break down grime and buildup associated with mildew.
• Allow the mixture to sit for at least 15 to 30 minutes. For deeper cleaning, cover the drain with a plug or cloth to keep the reaction concentrated.
• Using a soft-bristled brush, scrub around the drain opening and any accessible internal parts to dislodge built-up mildew and mold.
• Flush the drain with another round of boiling water to wash away loosened debris and residues.

 
Address Surrounding Areas
 

• Wipe down the shower walls and floor with a cleaning solution containing vinegar or a mildew-fighting cleaner, as odors might also emanate from nearby surfaces.
• If necessary, clean any drain screens or covers separately in a mixture of hot water, vinegar, and a bit of dish soap.

 
Implement Preventative Measures
 

• Consider using a drain cover designed with a removable insert to allow easy cleaning and to prevent buildup.
• After each shower, make sure to remove excess water and leave the bathroom door or window open to promote ventilation and quick drying.
• Regularly perform this cleaning routine—ideally on a monthly basis—to prevent the reoccurrence of mildew smell.
• Ensure that there are no leaks in the plumbing that may contribute extra moisture, fostering an environment where mildew can thrive.

It's worth noting that regular drain maintenance can help avoid recurring issues even in areas with distinct environmental challenges like St. Louis and Nashville.