Nashville sits on limestone bedrock covered by expansive clay soil. When the clay dries during summer droughts, it contracts and pulls away from foundation slabs. When heavy rains soak the soil in spring, it swells and pushes against slabs and underground pipes. This constant movement stresses copper and PVC lines. A water line that was stable for years suddenly develops a pinhole leak or a cracked joint. You see the result on your water bill before you see water pooling in your yard. This is why sudden spikes in water bills are so common in Davidson County.
Metro Nashville codes require pressure-reducing valves on homes where street pressure exceeds 80 psi. Many neighborhoods in Green Hills, Belle Meade, and West Meade have street pressure between 90 and 120 psi. If your pressure-reducing valve fails, system pressure spikes. Toilet fill valves run continuously. Supply lines rupture. Water heaters leak. A failing PRV can cause an unexplained high water bill and damage multiple fixtures simultaneously. We test system pressure on every service call because it affects everything downstream.