Create a seal over the drain opening. Plunge vigorously for 30 seconds. If water recedes, you’ve broken the clog. Run water to confirm.
Pull out leaves, mud, and twigs by hand or with a small trowel. Dispose in a bucket or bag. unclog outside drain
Pour 1 cup baking soda, then 1 cup vinegar down the drain. Cover the opening and wait 30 minutes. Follow with boiling water. This works best for grease or soap buildup. Create a seal over the drain opening