The depth of most kettles is less than ten meters. In most cases, kettle holes eventually fill with water, sediment, or plant growth (vegetation). If the kettle gets more water from surface or underground rivers or streams, it becomes a kettle lake. If the kettle gets its water from rainfall and/or snowfall (precipitation), existing groundwater, or a combination of the two, it is termed a kettle pond. A kettle wetland is a kettle pond in which plant matter grows. Kettle ponds that are not affected by the local groundwater table will usually become dry during the warm summer months, in which case they are called "ephemeral" (something which disappears on its own).