Relief well

[edit] Introduction

The International Levee Handbook, published by CIRIA in 2013, defines a relief well in water and flood management terms as: 'A vertically installed well consisting of a well screen surrounded by a filter material designed to prevent in-wash of foundation materials into the well. Relief wells are used extensively to relieve excess hydrostatic pressure in impervious foundation strata overlain by more impervious top strata, conditions that often exist landside of levees and downstream of dams and various hydraulic structures.'

Relief wells are also used in the fossil fuel industry as a control measure for natural gas and petroleum drilling.

[edit] History

The use of relief wells goes back to the early 1900s. They were initially used in the fossil fuel sector to manage well pressure. In the 1940s, relief wells were used to manage water pressure associated with dams. The technique was later adopted as a precautionary measure during construction to control water tables that could destabilise the ground..

[edit] Maintenance

The US Army Corps of Engineers has incorporated relief wells into the design and construction of several dam projects since the 1940s. Based on its experience, the organisation has observed that the life cycle of relief wells includes a slow but steady decline in pump efficiency after five years of operation. Regular maintenance and pump testing is required.

[edit] Related articles on Designing Buildings Wiki

• Dam construction.
• Flood.
• Levee.
• River engineering.
• Water engineering.
• Well.