Drains come in different sizes, from stormwater to kitchen sink drains, and every blockage varies in severity. A plunger will be sufficient for smaller drains to clear any debris lodged inside, such as coffee grounds and pasta. Be careful with using chemical drain cleaners.
For larger drains such as sewer and stormwater, a high-pressure jet blaster and possibly a CCTV camera will be needed to locate and clear the blockage. All blocked drains should be investigated thoroughly to find the cause and a permanent solution.