The terrors of the lawn look as though they are swimming as they tunnel, but they put a lot of force behind their shovel-like paws. The mole is quite a long lived animal for its size and can live up to 3-5 years. That is of course if they do not come into contact with a mole catcher.
image/text credit: The New York Times
Moles dig their tunnels on several levels or depths and use different parts of the tunnel system depending on conditions. Mole activity which is visible comes from the upper most tunnel systems. These tunnels are just a few inches deep.The main diet for moles is worms and other insects that live in the soil. When it rains and the soil becomes soaked, the earthworms and other insects move to the surface.via(mole-catcher).
The moles follow their food and start using the surface tunnels.Surface tunnels connect with deeper runways that are located 3 to 12 inches below the surface, but may be as deep as 40 inches. Deep runways are main passageways that are used daily as the mole travels to and from surface tunnels and its nest. Moles are fast diggers and can tunnel at a rate of 15 feet per hour.
In the summer when it is drier the earthworms go deeper where the soil is still moist, thus the moles use the deeper runs in order to stay with their food source. These deeper runs can be several feet deep.This is why moles appear to be more active in the winter and spring time.