Leaking sewer pipes can cause an unwanted permanent loss of urban groundwater; if this is a problem replacement or repair is an option. Replacement or renovation of the sewer pipes in these cases results in less discharge of groundwater and therefore an increase in the groundwater.
An example of a renovation method is relining, where a lining is inserted into the sewer pipe.
Such a renovation can earn back the cost of the investment, as this extends the life of the pipes.