Modern plumbing systems are powered by water pressure and gravity. Gravity removes the wastewater and sends it through the plumbing to the appropriate sewer or septic system, while water pressure from the main supply line charges the lines that carry water to plumbing faucets, taps, toilets and showers. Low pressure on a water tap is usually the result of a clogged water line or filter in the faucet head or a shutoff valve that is partially closed.
Turn the water on at the faucet. Find the water supply shutoff valves for the water tap. These valves are usually located under the counter or sink. In most instances, there will be two valves, one for hot water and a second for cold. Verify that these valves are completely open by turning the shutoff handles in a counterclockwise direction as far as they will go. Inspect the water pressure and verify it is flowing properly. If this did not fix the problem, proceed to the next step.
Turn the water faucet to the off position. Place a soft cloth over the assembly at the end of the faucet that houses the filter screen. Secure the adjustable pliers to this assembly, taking care not to scratch the finish of the faucet. Turn the pliers counterclockwise and remove the filter housing. Pull the filter screen from the filter housing with a screwdriver and replace or clean the screen as needed. Replace the housing by placing the threaded ends together and screwing into place in a clockwise direction. Tighten completely with the pliers wrapped in the soft cloth. Turn on the faucet and inspect the water pressure. If it is not properly pressurised, proceed to the next step.
Locate the main water supply line where it connects to the city's water main pipe. In most cases, this will be in the front yard and have a metal cover over the top of the connection. Remove the cover and turn the supply valve to your house to the fully open position with the water valve wrench. This valve should have a handle on top that is turned to be in line with the water line running to your house. Inspect the tap and verify that the water is now fully pressurised.
If none of these remedies fixes the problem, call a plumber. You may have broken or clogged water pipes that need to be repaired, replaced or flushed out. Installing a water booster pump can sometimes help when all other remedies for low water pressure fail.
A broken water line can cause serious damage to your home and property.