If the clog is deep, a plumbing snake (or auger) is required. Feed the cable into the gutter line until you feel resistance. Rotate the handle to break up the "grease plug" or hook onto solid debris to pull it back out. Professional Solutions for Stubborn Clogs
Using a garden hose on full pressure, direct water into the downspout. If water backs up, the blockage is still there – repeat step 4. If water flows freely into the drain, you’ve cleared it. kitchen gutter drain blocked